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We study a transport equation with nonlocal velocity and power law type damping. We show that a certain class of initial data smooth solution blows up in finite time. [ABSTRACT FROM AUTHOR]

Emerging rechargeable aluminium batteries (RABs) offer a sustainable option for next‐generation energy storage technologies with low cost and exemplary safety. However, the development of RABs is restricted by the limited availability of high‐performance cathode materials. Herein, we report two polyimide two‐dimensional covalent organic frameworks (2D‐COFs) cathodes with redox‐bipolar capability in RAB. The optimal 2D‐COF electrode achieves a high specific capacity of 132 mAh g−1. Notably, the electrode presents long‐term cycling stability (with a negligible ≈0.0007 % capacity decay per cycle), outperforming early reported organic RAB cathodes. 2D‐COFs integrate n‐type imide and p‐type triazine active centres into the periodic porous polymer skeleton. With multiple characterizations, we elucidate the unique Faradaic reaction of the 2D‐COF electrode, which involves AlCl2+ and AlCl4− dual‐ions as charge carriers. This work paves the avenue toward novel organic cathodes in RABs. [ABSTRACT FROM AUTHOR]

Neuartige Aluminium‐Akkumulatoren (AlAKs) stellen eine nachhaltige Option für Energiespeichertechnologien der nächsten Generation mit niedrigen Kosten und beispielhafter Sicherheit dar. Die Entwicklung von AlAKs wird jedoch durch die begrenzte Verfügbarkeit von Hochleistungs‐Kathodenmaterialien eingeschränkt. In diesem Artikel beschreiben wir zwei Polyimid‐ basierte zweidimensionale Covalent‐Organic‐Framework‐ (2D COF) Elektrodenmaterialien mit redox‐bipolarer Fähigkeit in AlAKs. Die optimierte 2D‐COF‐Elektrode erreicht eine hohe spezifische Kapazität von 132 mAh g−1. Die Elektrode weist eine langfristige Zyklenstabilität auf (mit einem vernachlässigbaren Kapazitätsabfall von ≈0.0007 % pro Zyklus) und übertrifft damit frühere Ergebnisse organischer AlAK‐Kathoden. Unsere 2D‐COFs beinhalten n‐Type‐Imide und p‐Type‐Triazine als aktive Zentren im periodisch‐porösen Polymerskelett. Anhand umfänglicher Charakterisierungen erklären wir die ungewöhnliche Faradische Reaktion der 2D‐COF‐Elektrode, bei der AlCl2+‐ und AlCl4− Dualionen als Ladungsträger beteiligt sind. Diese Arbeit ebnet den Weg zu neuartigen organischen Kathodenmaterialien in AlAKs. [ABSTRACT FROM AUTHOR]

Supramolecular self‐assembly is a promising strategy for stabilizing the photo‐sensitive components in photocatalysis. However, the underlying correlation between the enhanced photostability and supramolecular structure at the molecular level has not yet been fully understood. Herein, we develop a biomimetic vesicular membrane‐based polyporphyrin photocatalyst exhibiting excellent photocatalytic stability with at least activity time of 240 h in hydrogen generation. Time‐domain ab initio modelling together with transient absorption spectroscopy, visual frontier orbitals and Gibbs free energy calculation disclose that the ordered aggregation of porphyrin units in the vesicle membrane facilitates "hot" electron relaxation and the rapid dissipation of photo‐generated charges, thereby contributing to the longevity. This work deepens the molecular‐level understanding on photostability and photocatalytic mechanism of supramolecular photocatalysts. [ABSTRACT FROM AUTHOR]

Supramolecular self‐assembly is a promising strategy for stabilizing the photo‐sensitive components in photocatalysis. However, the underlying correlation between the enhanced photostability and supramolecular structure at the molecular level has not yet been fully understood. Herein, we develop a biomimetic vesicular membrane‐based polyporphyrin photocatalyst exhibiting excellent photocatalytic stability with at least activity time of 240 h in hydrogen generation. Time‐domain ab initio modelling together with transient absorption spectroscopy, visual frontier orbitals and Gibbs free energy calculation disclose that the ordered aggregation of porphyrin units in the vesicle membrane facilitates "hot" electron relaxation and the rapid dissipation of photo‐generated charges, thereby contributing to the longevity. This work deepens the molecular‐level understanding on photostability and photocatalytic mechanism of supramolecular photocatalysts. [ABSTRACT FROM AUTHOR]

Vinylene‐linked two‐dimensional covalent organic frameworks (V‐2D‐COFs) have shown great promise in electronics and optoelectronics. However, only a few reactions for V‐2D‐COFs have been developed hitherto. Besides the kinetically low reversibility of C=C bond formation, another underlying issue facing the synthesis of V‐2D‐COFs is the attainment of high (E)‐alkene selectivity to ensure the appropriate symmetry of 2D frameworks. Here, we tailor the E/Z selectivity of the Wittig reaction by employing a proper catalyst (i.e. Cs2CO3) to obtain more stable intermediates and elevating the temperature across the reaction barrier. Subsequently, the Wittig reaction is innovatively utilized for the synthesis of four crystalline V‐2D‐COFs by combining aldehydes and ylides. Importantly, the efficient conjugation and decent crystallinity of the resultant V‐2D‐COFs are demonstrated by their high charge carrier mobilities over 10 cm2 V−1 s−1, as revealed by non‐contact terahertz (THz) spectroscopy. [ABSTRACT FROM AUTHOR]

Vinylene‐linked two‐dimensional covalent organic frameworks (V‐2D‐COFs) have shown great promise in electronics and optoelectronics. However, only a few reactions for V‐2D‐COFs have been developed hitherto. Besides the kinetically low reversibility of C=C bond formation, another underlying issue facing the synthesis of V‐2D‐COFs is the attainment of high (E)‐alkene selectivity to ensure the appropriate symmetry of 2D frameworks. Here, we tailor the E/Z selectivity of the Wittig reaction by employing a proper catalyst (i.e. Cs2CO3) to obtain more stable intermediates and elevating the temperature across the reaction barrier. Subsequently, the Wittig reaction is innovatively utilized for the synthesis of four crystalline V‐2D‐COFs by combining aldehydes and ylides. Importantly, the efficient conjugation and decent crystallinity of the resultant V‐2D‐COFs are demonstrated by their high charge carrier mobilities over 10 cm2 V−1 s−1, as revealed by non‐contact terahertz (THz) spectroscopy. [ABSTRACT FROM AUTHOR]

In this paper, we use the modified potential well method to study the long time behaviors of solutions to the heat flow of H‐system in a bounded smooth domain of R2$$ {R}^2 $$. Global existence and finite time blowup of solutions are proved when the initial energy is in three cases. When the initial energy is low or critical, we not only give a threshold result for the global existence and blowup of solutions but also obtain the decay rate of the L2$$ {L}^2 $$ norm for global solutions. When the initial energy is high, sufficient conditions for the global existence and blowup of solutions are also provided. We extend the recent results which were. [ABSTRACT FROM AUTHOR]

Smart electronics and optoelectronics such as smart windows, touch panels and solar cells have profoundly changed our lives over the last decade, as a result of the development of transparent conductive electrodes. In particular, indium tin oxide-based electrodes dominate the market of the electronic and optoelectronic devices, but these electrodes have limitations. For instance, indium ores are only found in a few countries, such as China, Peru and Canada, thus limiting the global competitiveness of some countries. Moreover, indium tin oxide is quite brittle and easy to crack, thus unsuitable in flexible electronics. These issues may be solved by developing metal nanowire-based transparent conductive electrodes, such as Cu, Ag and Au nanowire electrodes. Here, we review the latest advances for metal nanowire-based transparent conductive electrodes, including the strategies for the synthesis of metal nanowires, the preparation of metal nanowire films by various solution-based deposition processes and their practical applications as electrodes in diverse flexible chromic devices. [ABSTRACT FROM AUTHOR]

We use the concept of the inside-(a, η, h) domain to construct a subsolution to the Dirichlet problem for minimal graphs over convex domains in hyperbolic space. As an application, we prove that the Hölder exponent max{1/a, 1/(n + 1)} for the problem is optimal for any a ∈ [2, +∞]. [ABSTRACT FROM AUTHOR]

Lung cancer has a high mortality rate and is very common. One of the main reasons for the poor prognosis of patients with lung cancer is the high incidence of metastasis. Ginsenoside Rh3, a rare ginsenoside extracted from Panax notoginseng, exhibits excellent anti-inflammatory and anti-tumor effects. Nonetheless, the inhibitory potential of Rh3 against lung cancer remains unknown. The target genes of Rh3 were screened by the PharmMapper database; the proliferation of lung cancer cells was detected by MTT assay; the migration and invasion of cells were detected by the Transwell method; and the expression of extracellular signal-regulated kinase (ERK) and EMT-related proteins in vivo and in vitro were detected by Western blotting. In addition, we established a lung metastasis model in nude mice using A549 cells to assess the effect of Rh3 on NSCLC tumor metastasis in vivo. Our findings suggest that Rh3 significantly inhibited lung cancer metastasis both in vivo and in vitro. It was determined by flow cytometry analysis that Rh3 notably inhibited cell proliferation by blocking the G1 phase. In addition, Rh3 inhibited metastasis in lung cancer cells and regulated the expression of metastasis-related proteins under hypoxia. Mechanistic studies suggested that Rh3 targeted ERK to inhibit lung cancer metastasis. The ERK inhibitor U0126 or siRNA-mediated knockdown of ERK had an enhanced effect on Rh3's ability to inhibit lung cancer metastasis. The studies revealed that the inhibitory effect of Rh3 on the metastatic ability of lung cancer cells may be supported by ERK-related signaling pathways. [ABSTRACT FROM AUTHOR]

The interest in two‐dimensional conjugated polymers (2D CPs) has increased significantly in recent years. In particular, vinylene‐linked 2D CPs with fully in‐plane sp2‐carbon‐conjugated structures, high thermal and chemical stability, have become the focus of attention. Although the Horner‐Wadsworth‐Emmons (HWE) reaction has been recently demonstrated in synthesizing vinylene‐linked 2D CPs, it remains largely unexplored due to the challenge in synthesis. In this work, we reveal the control of crystallinity of 2D CPs during the solvothermal synthesis of 2D‐poly(phenylene‐quinoxaline‐vinylene)s (2D‐PPQVs) and 2D‐poly(phenylene‐vinylene)s through the HWE polycondensation. The employment of fluorinated phosphonates and rigid aldehyde building blocks is demonstrated as crucial factors in enhancing the crystallinity of the obtained 2D CPs. Density functional theory (DFT) calculations reveal the critical role of the fluorinated phosphonate in enhancing the reversibility of the (semi)reversible C−C single bond formation. [ABSTRACT FROM AUTHOR]

Solid and flexible electrochromic (EC) devices require a delicate design of every component to meet the stringent requirements for transparency, flexibility, and deformation stability. However, the electrode technology in flexible EC devices stagnates, wherein brittle indium tin oxide (ITO) is the primary material. Meanwhile, the inflexibility of metal oxide usually used in an active layer and the leakage issue of liquid electrolyte further negatively affect EC device performance and lifetime. Herein, a novel and fully ITO‐free flexible organic EC device is developed by using Ag–Au core–shell nanowire (Ag–Au NW) networks, EC polymer and LiBF4/propylene carbonate/poly(methyl methacrylate) as electrodes, active layer, and solid electrolyte, respectively. The Ag–Au NW electrode integrated with a conjugated EC polymer together display excellent stability in harsh environments due to the tight encapsulation by the Au shell, and high area capacitance of 3.0 mF cm−2 and specific capacitance of 23.2 F g−1 at current density of 0.5 mA cm−2. The device shows high EC performance with reversible transmittance modulation in the visible region (40.2% at 550 nm) and near‐infrared region (−68.2% at 1600 nm). Moreover, the device presents excellent flexibility (>1000 bending cycles at the bending radius of 5 mm) and fast switching time (5.9 s). [ABSTRACT FROM AUTHOR]

Covering: 2010 to 2020 This review article describes how cationic rearrangement reactions have been used in natural product total synthesis over the last decade as a case study for the many productive ways by which isomerization reactions are enabling for synthesis. This review argues that isomerization reactions in particular are well suited for computational evaluation, as relatively simple calculations can provide significant insight. [ABSTRACT FROM AUTHOR]

In this paper the dual Orlicz-Minkowski problem, a generalization of the Lp dual Minkowski problem, is studied. By studying a flow involving the Gauss curvature and support function, we obtain a new existence result of solutions to this problem for smooth measures. [ABSTRACT FROM AUTHOR]

This manuscript describes predicted NMR shifts for the limonoid natural product xylogranatin F. The 1H and 13C NMR shifts of four diastereomers were evaluated by GIAO and hybrid DFT/parametric DU8+ methods. The results of the 1H and 13C NMR calculations for both the GIAO method and the DU8+ calculations suggest the revised structure that was recently reassigned by chemical synthesis. Furthermore, we show that while DU8+ provides superior accuracy with less computation time, GIAO points to the correct structure with more distinguishable data in this case study. [ABSTRACT FROM AUTHOR]

In this study, we fabricated multifunctionalized hydrogel scaffolds based on hyaluronic acid (HA)-tyrosine and human-like collagen (HLC) by crosslinking with 1, 4-butanedioldiglycidyl ether (BDDE) for soft tissue fillers. The physicochemical of HA-tyrosine/BDDE (HTB) and various proportions of HA-tyrosine/BDDE/HLC (HTBH) hydrogels were characterized by swelling ratio, mechanical strength, morphology and thermal stability. The results demonstrated various HTBH hydrogels had superior performance in mechanical properties than HTB hydrogels. The biodegradation in vitro results demonstrated the degradation of HTBH hydrogels were slower than HTB hydrogels, and residual masses of HTBH hydrogels varied with different proportions of HA-tyrosine and HLC in the presence of the combination of HAse/collagenase I. The cell counting kit-8 (CCK-8), Hoechst/PI staining and cell adhesion of various HTBH hydrogels showed less cytotoxic and superior fibroblast attachment than those of HTB hydrogels. Moreover, subcutaneous injections of HTBH hydrogels containing high proportions of HLC in mice and rabbits all exhibit better biocompatibility and anti-biodegradation compared to HTB hydrogels after 1, 4, 8, 12 and 16 weeks. Hematoxylin-eosin staining (H&E), immunohistochemical and transmission electron microscope (TEM) analysis results indicated HTBH hydrogels had less intense inflammatory responses with increase proportion of HLC. Taken together, HTBH hydrogels had great potential application as ideal soft tissue fillers with excellent mechanical properties, biological stability and biocompatibility. [ABSTRACT FROM AUTHOR]

Ginsenoside Rg5, a rare saponin belonging to the family of protopanaxadiol ginsenosides, has been demonstrated to have potential anti-tumor effects in various cancers. However, the effect of Rg5 on human gastric cancer and the underlying molecular mechanisms remain to be elucidated. In this study, Rg5 could suppress cell proliferation by causing G2/M phase arrest. Treatment with Rg5 could induce apoptosis through the extrinsic death receptor and intrinsic mitochondrial pathways. Autophagy induction was demonstrated by the formation of autophagosomes and autophagy-related proteins. Rg5-induced cell death was inhibited by the autophagy inhibitor 3-MA and apoptosis inhibitor Z-VAD-FMK. Moreover, the suppression of apoptosis weakened Rg5-induced autophagy, while the inhibition of autophagy attenuated Rg5-induced apoptosis. Further studies revealed that Rg5 induced ROS production and activated MAPK signaling pathways. The ROS scavenger NAC markedly diminished G2/M arrest, apoptosis, autophagy and activation of MAPK pathways induced by Rg5. The p38 inhibitor SB203580 or knockdown of p38 by siRNA clearly reversed Rg5-induced apoptosis and G2/M arrest. The JNK inhibitor SP600125 or knockdown of JNK by siRNA markedly attenuated Rg5-induced G2/M arrest, apoptosis and autophagy. The inhibition of ERK inhibitor U0126 or knockdown of ERK by siRNA clearly restored Rg5-induced apoptosis and autophagy. Finally, Rg5 significantly suppressed the growth of xenograft gastric tumors with fewer side effects. Overall, the evidence suggested that Rg5 is a novel and promising strategy for the treatment of gastric cancer owing to its high efficacy, multiple mechanisms and fewer side effects. [ABSTRACT FROM AUTHOR]

The BAP module, comprising BRASSINAZOLE RESISTANT 1 (BZR1), AUXIN RESPONSE FACTOR 6 (ARF6), and PHYTOCHROME‐INTERACTING FACTOR 4 (PIF4), functions as a molecular hub to orchestrate plant growth and development. In Arabidopsis thaliana, components of the BAP module physically interact to form a complex system that integrates light, brassinosteroid (BR), and auxin signals. Little is known about the origin and evolution of the BAP module. Here, we conducted comparative genomic and transcriptomic analyses to investigate the evolution and functional diversification of the BAP module. Our results suggest that the BAP module originated in land plants and that the ζ, ε, and γ whole‐genome duplication/triplication events contributed to the expansion of BAP module components in seed plants. Comparative transcriptomic analysis suggested that the prototype BAP module arose in Marchantia polymorpha, experienced stepwise evolution, and became established as a mature regulatory system in seed plants. We developed a formula to calculate the signal transduction productivity of the BAP module and demonstrate that more crosstalk among components enables higher signal transduction efficiency. Our results reveal the evolutionary history of the BAP module and provide insights into the evolution of plant signaling networks and the strategies employed by plants to integrate environmental and endogenous signals. [ABSTRACT FROM AUTHOR]

Ternary metal sulfides normally have narrow band gap energy levels, leading to fast recombination of photogenerated carriers. The construction of heterojunctions is generally believed to boost the photogenerated carrier efficiency via capturing and transferring electrons, and thus improving the photocatalytic activity. In this paper, different ratios of AgInS2–SnIn4S8 composites were synthesized by a microwave-assisted hydrothermal method, and the molar ratio of SnIn4S8:AgInS2 = 0.5:1 is determined as the optimal ratio based on the experimental results of visible photocatalytic degradation of methyl orange (MO). Furthermore, AgIn5S8/AgInS2–SnIn4S8 composites were successfully prepared by changing the ratio of In, S element, and AgNO3. The component, structural morphology, and surface physicochemical properties of the composites were characterized by X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, ultraviolet–visible diffuse reflectance absorption spectroscopy, and nitrogen adsorption–desorption tests. The results show that AgInS2 and AgIn5S8 are compounded with SnIn4S8 to form a heterogeneous structure. After the formation of heterogeneous structures, light absorption properties are changed and light absorption range is broadened due to stronger light absorption capacity in AgInS2 and AgIn5S8. As they have matched energy band structures, the electron transfer paths are increased and the e−–h+ lifetime is prolonged, which leads to enhanced photocatalytic performance of AgIn5S8/AgInS2–SnIn4S8 composites. Moreover, the formation of regular and homogeneous flower globose structure under the effect of microwave polarization also has an important contribution to the improvement of their photocatalytic performance. AgIn5S8/AgInS2–SnIn4S8 composites exhibit a certain degradation ability towards MO, and the degradation is almost complete within 180 min under visible light irradiation. Finally, through trapping experiments with the addition of different radical trapping agents and the ESR tests, photocatalytic active species are identified, and thus the possible photocatalytic reaction mechanism of AgIn5S8/AgInS2–SnIn4S8 composite is inferred. [ABSTRACT FROM AUTHOR]

This communication describes polymer vesicles self-assembled from hyperbranched polymers (branched polymersomes (BPs)) as scaffolds, conceptually mimicking the natural light-harvesting system in aqueous solution. The system is constructed with hydrophobic 4-chloro-7-nitro-2,1,3-benzoxadiazole (NBD-Cl) as donors encapsulated in the hydrophobic hyperbranched cores of the vesicles and the hydrophilic Rhodamine B (RB) as acceptors incorporated on the surface of the vesicles through the cyclodextrin (CD)/RB host-guest interactions, through which the donors and acceptors are spatially separated to effectively avoid the self-quenching between donors. This vesicular light harvesting system has presented good energy transfer efficiency of about 80% in water, and can be used as the ink to write multiclolor letters. In addition, due to the giant dimension of BPs, the real-time fluorescent images of the vesicles under an optical microscope can be observed to prove the light-harvesting process. It is supposed that such a vesicular light-harvesting antenna can be used to construct artificial photosynthesis systems in the future. [ABSTRACT FROM AUTHOR]

A dandelion-like supramolecular polymer (DSP) with a 'sphere-star-parachute' topological structure consisting of a spherical hyperbranched core and many parachute-like arms is constructed by the non-covalent host-guest coupling between a cyclodextrin-endcapped hyperbranched multi-arm copolymer (host) and many functionalized adamantanes with each having three alkyl chain arms (guests). The obtained DSPs can further self-assemble into nanotubes in water in a hierarchical way from vesicles to nanotubes through sequential vesicle aggregation and fusion steps. The nanotubes have a bilayer structure consisting of multiple 'hydrophobic-hyperbranched-hydrophilic' layers. Such a structure is very useful for constructing a chlorosome-like artificial aqueous light-harvesting system, as demonstrated here, via the incorporation of hydrophobic 4-(2-hydroxyethylamino)-7-nitro-2,1,3-benzoxadiazole as donors inside the hyperbranched cores of the nanotubes and the hydrophilic Rhodamine B as the acceptors immobilized on the nanotube surfaces. This as-prepared nanotube light harvesting system demonstrates unexpectedly high energy transfer efficiency (above 90%) in water. This extends supramolecular polymers with more complex topological structure, special self-assembly behavior, and new functionality. [ABSTRACT FROM AUTHOR]

A novel hybrid light-harvesting antenna with a srikaya-like structure of multi-graphene quantum dots (GQDs) as donors and one porphyrin unimolecular micelle as the acceptor was constructed through electrostatic self-assembly. The constructed antenna showed a high energy transfer efficiency of up to 93.6% and an antenna effect of 7.3 in an aqueous solution. [ABSTRACT FROM AUTHOR]

In this paper, we consider the Dirichlet problem for hypersurfaces M = graph u of anisotropic prescribed mean curvature H = H ( x , u , N ) on unbounded domain Ω, where N is the unit normal to M at ( x , u ) . As a corollary of the result, we obtain the existence of translating solutions to the mean curvature flow with a forcing term on unbounded domains. The approach used here is a modified version of classical Perron's method, where the solutions to minimal surface equation are used as supersolutions and a family of auxiliary functions is constructed as local subsolutions. [ABSTRACT FROM AUTHOR]

Amicelle-like hybrid natural-artificial light-harvesting nanosystem was prepared through protein-framed electrostatic self-assembly of phycocyanin and a four-armed porphyrin star polymer. The nanosystem has a special structure of pomegranate-like unimolecular micelle aggregate with one phycocyanin acceptor in the center and multiple porphyrin donors in the shell. It can inhibit donor self-quenching effectively and display efficient transfer of excitation energy (about 80.1%) in water. Furthermore, the number of donors contributing to a single acceptor could reach as high as about 179 in this nanosystem. [ABSTRACT FROM AUTHOR]

The rare ginsenoside Compound K (CK) is an attractive ingredient in traditional medicines, cosmetics, and the food industry because of its various biological activities. However, it does not exist in nature. The commonly used method for the production of CK is enzymatic conversion. In order to further improve the catalytic efficiency and increase the CK content, a thermostable β-glycosidase from Sulfolobus solfataricus was successfully expressed in Pichia pastoris and secreted into fermentation broth. The recombinant SS-bgly in the supernatant showed enzyme activity of 93.96 U/mg at 120 h when using pNPG as substrate. The biotransformation conditions were optimized at pH 6.0 and 80 °C, and its activity was significantly enhanced in the presence of 3 mM Li+. When the substrate concentration was 10 mg/mL, the recombinant SS-bgly completely converted the ginsenoside substrate to CK with a productivity of 507.06 μM/h. Moreover, the recombinant SS-bgly exhibited extraordinary tolerance against high substrate concentrations. When the ginsenoside substrate concentration was increased to 30 mg/mL, the conversion could still reach 82.5% with a productivity of 314.07 μM/h. Thus, the high temperature tolerance, resistance to a variety of metals, and strong substrate tolerance make the recombinant SS-bgly expressed in P. pastoris a potential candidate for the industrial production of the rare ginsenoside CK. [ABSTRACT FROM AUTHOR]

Abstract: Milk proteins are natural vehicles for bioactive molecules. Molecules of casein, the principal protein in milk, can reportedly form complexes with bioactive molecules at the molecular level. The interaction of β-casein with folic acid (a synthetic form of the B group vitamin known as folates) was studied using fluorescence, absorption spectroscopy and circular dichroism. It was found that folic acid bound to β-casein by hydrophobic contacts with a dissociation constant of ~10−5 M. This interaction did not affect changes in β-casein structure caused by sodium dodecyl sulfate but did reduce the sensitivity of the structure to sodium chloride. Binding to β-casein appeared to inhibit the photodecomposition of folic acid. These results should provide insight into β-casein-bioactive-molecule interaction mechanisms and aid the development of protein-based carrier systems for the delivery of bioactive molecules. [Copyright &y& Elsevier]

Abstract: In this paper, we study the evolution of convex hypersurfaces by inverse mean curvature minus an external force field c. We prove that the flow will preserve the convexity for any c. If on the initial surface, we prove that the flow will expand the hypersurface for all time, and after rescaling the hypersurface will converge to a sphere. If on the initial surface, we show that the maximum existence time of the flow is finite, and the hypersurface will contract to a point when approaching the final time. [Copyright &y& Elsevier]

The author studies the L gradient flow of the Helfrich functional, which is a functional describing the shapes of human red blood cells. For any λ ≥ 0 and c, the author obtains a lower bound on the lifespan of the smooth solution, which depends only on the concentration of curvature for the initial surface. [ABSTRACT FROM AUTHOR]

In this paper, we study the evolution of hypersurfaces by powers of mean curvature minus an external force field. We prove that when the power is 2, the flow has a long-time smooth solution for all time under some conditions. Those conditions are that the second fundamental form on the initial submanifolds is not too large, the external force field, with its any order derivatives, is bounded, and the field is convex with its eigenvalues satisfying a pinch inequality. [ABSTRACT FROM AUTHOR]

Abstract: A solid phase strategy has been developed for the synthesis of 3-(5-arylpyridin-2-yl)-4-hydroxycoumarins. The key transformation is an intramolecular ipso substitution reaction which forms the coumarin heterocycle and culminates with cleavage of product from the polymer support. The pyridine moiety at C3 can be further modified with Suzuki coupling. A sample library with two diversity elements has been synthesized to demonstrate this ipso substation-based cyclo-elimination strategy. [Copyright &y& Elsevier]

This article explores the synthesis and properties of Vinylen-bridged cationic 2DP films (V-C2DPs) for use in anion-selective electrodes and high-voltage zinc-ion batteries. The films are highly crystalline and possess oriented one-dimensional channels, which enhance anion-selective transport. The authors conducted experiments and calculations to understand the reactivity and structure of the films, finding that synthesis on the water surface had advantages over aqueous solution synthesis. The films exhibited a well-ordered hexagonal lattice structure and showed improved electrochemical performance when used as coatings for graphite cathodes in zinc-ion batteries. The study highlights the potential of V-C2DP films for next-generation energy devices. The research was supported by various funding sources and the data is available upon request from the authors. [Extracted from the article]

Vinylene‐linked two‐dimensional polymers (V‐2DPs) and their layer‐stacked covalent organic frameworks (V‐2D COFs) featuring high in‐plane π‐conjugation and robust frameworks have emerged as promising candidates for energy‐related applications. However, current synthetic approaches are restricted to producing V‐2D COF powders that lack processability, impeding their integration into devices, particularly within membrane technologies reliant upon thin films. Herein, we report the novel on‐water surface synthesis of vinylene‐linked cationic 2DPs films (V‐C2DP‐1 and V‐C2DP‐2) via Knoevenagel polycondensation, which serve as the anion‐selective electrode coating for highly‐reversible and durable zinc‐based dual‐ion batteries (ZDIBs). Model reactions and theoretical modeling revealed the enhanced reactivity and reversibility of the Knoevenagel reaction on the water surface. On this basis, we demonstrated the on‐water surface 2D polycondensation towards V‐C2DPs films that show large lateral size, tunable thickness, and high chemical stability. Representatively, V‐C2DP‐1 presents as a fully crystalline and face‐on oriented film with in‐plane lattice parameters of a=b≈43.3 Å. Profiting from its well‐defined cationic sites, oriented 1D channels, and stable frameworks, V‐C2DP‐1 film possesses superior bis(trifluoromethanesulfonyl)imide anion (TFSI−)‐transport selectivity (transference, t_=0.85) for graphite cathode in high‐voltage ZDIBs, thus triggering additional TFSI−‐intercalation stage and promoting its specific capacity (from ~83 to 124 mAh g−1) and cycling life (>1000 cycles, 95 % capacity retention). [ABSTRACT FROM AUTHOR]

The nanocomposite material C@Pt/MoS 2 @CdS was prepared by a simple microwave-assisted hydrothermal method combined with photoreduction method. The crystal structure, microstructure, and surface physical chemistry properties of the material were analyzed by X-ray diffraction (XRD), ultraviolet–visible diffuse reflectance absorption spectroscopy (UV–vis/DRS), X-ray photoelectron energy spectroscopy (XPS), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HR-TEM), nitrogen adsorption–desorption measurement, photoluminescence spectroscopy (PL), and electrochemical tests. As a result, this material has full-spectrum light absorption property and the composited CdS presents a good hexagonal phase. Moreover, the composite material presents a nanorod-like multi-layer core-shell structure, wherein the rod-like MoS 2 @CdS surface is covered with Pt and C. The formation of the multi-layer core-shell structure increases the specific surface area of as-composite material and strengthens its light absorption performance. The electrochemical impedance and transient photocurrent test results show that C@Pt/MoS 2 @CdS has the highest charge separation efficiency and enhanced photocurrent density compared with other systems. Photogenerated charge carriers have higher separation efficiency, and photogenerated electrons and holes exhibit longer life. During the photocatalysis experiments, the nanocomposite C@Pt/MoS 2 @CdS shows enhanced photodegradation activity under multi-modal photocatalytic experiments and excellent stability under visible light irradiation. In addition, C@Pt/MoS 2 @CdS has a strong photocatalytic water splitting ability. Under the same experimental conditions, its hydrogen production is 60 times that of commercially available P25. Through capture experiments, the reactive species in the photocatalytic reaction process were determined, and the possible photocatalytic reaction mechanism of this multi-layer core-shell C@Pt/MoS 2 @CdS nanocomposite was inferred. • Constructed a multi-layer core-shell structure photocatalytic composite material. • Improved the photocatalytic activity and stability of CdS-based photocatalyst. • The hydrogen production of C@Pt/MoS 2 @CdS was approximately 60 times that of commercially available P25. • Recombination rate of photogenerated charge carriers was effectively restrained. [ABSTRACT FROM AUTHOR]

Green plants (Viridiplantae) are ancient photosynthetic organisms that thrive both in aquatic and terrestrial ecosystems, greatly contributing to the changes in global climates and ecosystems. Significant progress has been made toward understanding the origin and evolution of green plants, and plant biologists have arrived at the consensus that green plants first originated in marine deep‐water environments and later colonized fresh water and dry land. The origin of green plants, colonization of land by plants and rapid radiation of angiosperms are three key evolutionary events during the long history of green plants. However, the comprehensive understanding of evolutionary features and molecular innovations that enabled green plants to adapt to complex and changeable environments are still limited. Here, we review current knowledge of phylogenetic relationships and divergence times of green plants, and discuss key morphological innovations and distinct drivers in the evolution of green plants. Ultimately, we highlight fundamental questions to advance our understanding of the phenotypic novelty, environmental adaptation, and domestication of green plants. [ABSTRACT FROM AUTHOR]

In this paper, bayberry-like BiOBr/AgBr/LaPO 4 nanocomposites were synthesized by microwave-assisted hydrothermal treatment. The composition, structure, and morphology of BiOBr/AgBr/LaPO 4 nanocomposites were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV−visible diffuse reflectance (UV−vis/DRS), high-power transmission electron microscopy (HR-TEM), scanning electron microscopy (SEM), and N 2 adsorption−desorption measurements. The results show that the light absorption capacity of BiOBr/AgBr/LaPO 4 is clearly enhanced and that a bayberry-like structure is more likely to produce diffraction and reflection of light on the surfaces of composites. AgBr in the composite is capable of reducing to Ag0 after light irradiation. Ag0, acting as a charge-transfer mediator, can be the medium, thus forming a Z-scheme structure. At the same time, the surface plasmon resonance (SPR) effect of Ag0 exhibits higher activity in the simulated sunlight photocatalysis process in BiOBr/AgBr/LaPO 4. The photoelectrochemical methods further indicate that BiOBr/AgBr/LaPO 4 possesses the best electron−hole pair separation ability. Furthermore, two different interface electron transfer modes and multipathway photoelectron migration in the composite are determined. • A bayberry-like structure BiOBr/AgBr/LaPO 4 composite was synthesized. • AgBr in the composite is capable of reduction to form Ag0 after light irradiation. • The presence of Ag0 results in forming two different electron transport pathes. • Two electron transfer modes synergistically improve photocatalytic ability. [ABSTRACT FROM AUTHOR]

A novel, three-dimensional, porous, human-like collagen (HLC)/nano-hydroxyapatite (n-HA) scaffold cross-linked by 1,2,7,8-diepoxyoctane (DEO) was successfully fabricated, which showed excellent mechanical and superior biological properties for bone tissue regeneration in this study. The physicochemical characterizations of different n-HA/HLC/DEO (nHD) scaffolds were investigated by determining the morphology, compression stress, elastic modulus, Young's modulus and enzymatic hydrolysis behavior in vitro. The results demonstrated that nHD-2 and nHD-3 scaffolds showed superior mechanical properties and resistance to enzymatic hydrolysis compared to nHD-1 scaffolds. The cell viability, live cell staining and cell adhesion analysis results demonstrated that nHD-2 scaffolds exhibited low cytotoxicity and excellent cytocompatibility compared with nHD-1 and nHD-3 scaffolds. Furthermore, subcutaneous injections of nHD-2 scaffolds in rabbits produced superior anti-biodegradation effects and histocompatibility compared with injections of nHD-1 and nHD-3 scaffolds after 1, 2 and 4 weeks. In addition, the repair of bone defects in rabbits demonstrated that nHD-2 scaffolds presented an improved ability for guided bone regeneration and reconstruction compared to commercially available bone scaffold composite hydroxyapatite/collagen (HC). Collectively, the results show that nHD-2 scaffolds show promise for application in bone tissue engineering due to their excellent mechanical properties, anti-biodegradation, anti-biodegradation, biocompatibility and bone repair effects. [ABSTRACT FROM AUTHOR]

DNA methylation is an important epigenetic mark implicated in selective rRNA gene expression, but the DNA methylation readers and effectors remain largely unknown. Here, we report a protein complex that reads DNA methylation to regulate variant-specific 45S ribosomal RNA (rRNA) gene expression in Arabidopsis (Arabidopsis thaliana). The complex, consisting of METHYL-CpG-BINDING DOMAIN PROTEIN5 (MBD5), MBD6, ALPHA-CRYSTALLIN DOMAIN PROTEIN15.5 (ACD15.5), and ACD21.4, directly binds to 45S rDNA. While MBD5 and MBD6 function redundantly, ACD15.5 and ACD21.4 are indispensable for variant-specific rRNA gene expression. These 4 proteins undergo phase separation in vitro and in vivo and are interdependent for their phase separation. The α-crystallin domain of ACD15.5 and ACD21.4, which is essential for their function, enables phase separation of the complex, likely by mediating multivalent protein interactions. The effector MICRORCHIDIA6 directly interacts with ACD15.5 and ACD21.4, but not with MBD5 and MBD6, and is recruited to 45S rDNA by the MBD–ACD complex to regulate variant-specific 45S rRNA expression. Our study reveals a pathway in Arabidopsis through which certain 45S rRNA gene variants are silenced, while others are activated. The METHYL-CpG-BINDING DOMAIN–ALPHA-CRYSTALLIN DOMAIN protein complex reads CG DNA methylation and recruits the effector protein MICRORCHIDIA6 to regulate variant-specific 45S rRNA expression. [ABSTRACT FROM AUTHOR]

Summary: Plants evolved sophisticated machineries to monitor levels of external nitrogen supply, respond to nitrogen demand from different tissues and integrate this information for coordinating its assimilation. Although roles of inorganic nitrogen in orchestrating developments have been studied in model plants and crops, systematic understanding of the origin and evolution of its assimilation and signaling machineries remains largely unknown.We expanded taxon samplings of algae and early‐diverging land plants, covering all main lineages of Archaeplastida, and reconstructed the evolutionary history of core components involved in inorganic nitrogen assimilation and signaling.Most components associated with inorganic nitrogen assimilation were derived from the ancestral Archaeplastida. Improvements of assimilation machineries by gene duplications and horizontal gene transfers were evident during plant terrestrialization. Clusterization of genes encoding nitrate assimilation proteins might be an adaptive strategy for algae to cope with changeable nitrate availability in different habitats. Green plants evolved complex nitrate signaling machinery that was stepwise improved by domains shuffling and regulation co‐option.Our study highlights innovations in inorganic nitrogen assimilation and signaling machineries, ranging from molecular modifications of proteins to genomic rearrangements, which shaped developmental and metabolic adaptations of plants to changeable nutrient availability in environments. [ABSTRACT FROM AUTHOR]

In general, quantum dots have the property of generating a plurality of charge carriers using hot electrons or using a single high-energy photon to improve the photocatalytic properties of the material. In this paper, CdS QDs@CdIn2S4/CdWO4 modified by CdS QDs was synthesized by the microwave-assisted hydrothermal method, and its composition, crystal structure, morphology, and surface physicochemical properties were well characterized. Electron microscopy results showed that CdS QDs@CdIn2S4/CdWO4 composite material exhibited a sheet structure with a length of ca. 350 nm and a width of ca. 50 nm, and CdS QDs uniformly distributes with a diameter of about 5 nm on the sheet structure. UV-visible diffuse reflectance tests showed that the combination of CdS QDs and CdIn2S4 can extend the light absorption range of CdWO4 to the visible region. Photoluminescence spectroscopy confirmed that CdS QDs had efficient electron transport capabilities. The multi-mode photocatalytic activity of CdS QDs@CdIn2S4/CdWO4 showed an excellent ability to degrade organic pollutants. Under the conditions of no co-catalyst and Na2S-Na2SO3 as the sacrificial agent, the hydrogen production of CdS QDs@CdIn2S4/CdWO4 can reach 221.3 μmol g−1 when exposed to visible light (λ > 420 nm) for 8 h.Multi-mode photocatalytic performances of CdS QDs modified CdIn2S4/CdWO4 nanocomposites with high electron transfer ability.Due to CdS QDs owning stronger electron transfer ability, CdS QDs@CdIn2S4/CdWO4 exhibited higher activity in multi-mode photocatalytic processes and the enhanced activity in splitting water into hydrogen. [ABSTRACT FROM AUTHOR]

Skin defects caused by various reasons are currently common clinical problems. At present, hydrogels have been proposed as tissue-engineered skin scaffolds to regenerate the tissues of the defect. We used human-like collagen (HLC), which was isolated and purified after high-density fermentation of recombinant E. coli BL21 The gel uses HLC and carboxymethylated chitosan (CCS) as raw materials and combines enzyme-chemical double cross-linking technology to form a three-dimensional porous network structure that mimics the human extracellular matrix, providing attachment points and nutrients for cell growth and proliferation. For comparison, we used a common hydrogel raw material, gelatin, to prepare a hydrogel in the same way. The experimental results show that the HLC-CCS skin scaffold hydrogel has good mechanical properties, high porosity and good histocompatibility. And full-thickness skin defect repair experiments show that this hydrogel has a good ability to promote skin tissue regeneration at the wound. In summary, this HLC-based double-crosslinked hydrogel can be used as a project strategy for skin defect repair. [ABSTRACT FROM AUTHOR]

Aim at the low real-time performance and high false alarm rate of the traditional fall detection model, AdaBoost multi-core support vector machine model (ADB-MKSVM) was proposed which was used to detect and identify the falling action. Based on the improved AdaBoost model framework, the model took multi-core support vector machine as the basis classifier and assembled these basis classifiers to form a stronger final classifier. According to the distribution of human movement data and whether the classification of each sample in each training set is correct or not, and the overall classification accuracy last time, the weight of each sample was determined. The dynamic weight allocation method was used to improve the recognition rate of the fall action. The test results showed that this model had good classification performance, and the method of binding the sensor on the waist position could effectively improve the detection effect of the fall action. The accuracy rate was 99. 33%,the fall detection rate was 63. 6%,and the false detection rate was 1. 62% . [ABSTRACT FROM AUTHOR]

Abstract Alcoholic liver disease (ALD), as one of the most common diseases, has become a global threat to human health. The aim of this study was designed to investigate the hepatoprotective effects of ginsenoside Rk3 against ALD and to discover the potential mechanisms of these protective effects. Mice were intragastrically administered 50% alcohol and treated with ginsenoside Rk3 (25 and 50 mg/kg) once per day for 6 weeks. The results indicated that ginsenoside Rk3 promoted hepatic function through significant downgrading AST and ALT levels in the serum, attenuating oxidative stress, and restoring antioxidant balance in hepatic tissue. Additionally, ginsenoside Rk3 significantly reduced the expression of inflammatory cytokines, such as NF-κB, TNF-α, IL-6, and IL-1β in the mice. Furthermore, ginsenoside Rk3 supplementation significantly inhibited apoptotic protein expression in the liver. The present study clearly demonstrates that ginsenoside Rk3 exerts a protective effect against ALD-induced liver injury because of its antioxidant, anti-apoptotic, and anti-inflammatory activities. The findings from the present investigation show that ginsenoside Rk3 might be a promising candidate treatment agent against ALD. Graphical abstract Image 1 Highlights • Ginsenoside Rk3 prevented liver injury induced by binge ethanol. • Ginsenoside Rk3 ameliorated the inflammation and oxidative stress under the condition of chronic ethanol exposure. • Ginsenoside Rk3 inhibited the apoptosis induced by ethanol partially through caspase pathways. [ABSTRACT FROM AUTHOR]

Plasmonic nanoparticles (NPs), such as Au, Ag, and Cu, are considered as promising photothermal materials and attract extensive attention for freshwater production by solar steam generation. However, high cost, narrow absorption range and/or poor stability greatly limit their practical applications. Herein, a high‐efficiency solar energy conversion material consisting of low‐cost non‐metal, extremely thermally‐stable plasmonic TiN NPs and hydrophilic semi‐reduced graphene oxide (semi‐rGO), with broadband solar absorption capability, by a fast in situ microwave reduction method is prepared. The 2D semi‐rGO serves as a support for the loading of plasmonic NPs, and meanwhile accelerates the transport and evaporation of water due to its hydrophilicity. Then, decoration of plasmonic TiN NPs further enhances the solar photon absorption and hydrophilicity while suppressing the heat loss, thanks to the layered structure of TiN/semi‐rGO, improving overall solar energy utilization. Owing to the enhanced absorption and unique layered nanostructure with strong interfacial interaction, the optimal sample of TiN/semi‐rGO‐25% absorber achieves a high and stable water evaporation rate of ≈1.76 kg m−2 h−1 with an energy efficiency as high as 99.1% under 1 sun illumination. Furthermore, this plasmonic TiN/semi‐rGO absorber is capable of producing high‐quality freshwater from sustainable seawater desalination and wastewater purification processes. [ABSTRACT FROM AUTHOR]

The efficacy of Lactobacillus as an antibiotic substitute has been investigated as one of the potential strategies to prevent Salmonella infection in poultry. The purpose of this study was to explore the antibacterial activity of Lactobacillus fermentum 1.2133 (Lact. fermentum 1.2133) against Salmonella pullorum CVCC533 (Salm. pullorum CVCC533) and its effect on chickens infected with Salm. pullorum CVCC533. Results showed that Lact. fermentans 1.2133 has antibacterial activity against Salm. pullorum CVCC533 and the cell-free fermentation supernatant of Lact. fermentum 1.2133 had a bactericidal effect on the bacteria in the Salm. pullorum CVCC533 biofilm by significantly reducing the number of Salmonella and aerobic bacteria in the chicken duodenum, ileum, and cecum, including Escherichia shigella (P  < 0.05), improved the species abundance of Lactobacilli (P  < 0.05). The damage to the chicken intestine by Salm. pullorum CVCC533 was reduced as the expression of avian beta-defensin 2 (AvBD2) mRNA in chicken small intestine was increased (P  < 0.05). The results showed that Lact. fermentum 1.2133 had the potential to be a probiotic for poultry due to its regulation of intestinal AvBD2 mRNA as well as its intestinal flora. [ABSTRACT FROM AUTHOR]

Small nucleolar RNAs (snoRNAs) are noncoding RNAs (ncRNAs) that guide chemical modifications of structural RNAs, which are essential for ribosome assembly and function in eukaryotes. Although numerous snoRNAs have been identified in plants by high-throughput sequencing, the biological functions of most of these snoRNAs remain unclear. Here, we identified box C/D SnoR28.1s as important regulators of plant growth and development by screening a CRISPR/Cas9-generated ncRNA deletion mutant library in Arabidopsis thaliana. Deletion of the SnoR28.1 locus, which contains a cluster of three genes producing SnoR28.1s, resulted in defects in root and shoot growth. SnoR28.1s guide 2′- O -ribose methylation of 25S rRNA at G2396. SnoR28.1s facilitate proper and efficient pre-rRNA processing, as the SnoR28.1 deletion mutants also showed impaired ribosome assembly and function, which may account for the growth defects. SnoR28 contains a 7-bp antisense box, which is required for 2′- O -ribose methylation of 25S rRNA at G2396, and an 8-bp extra box that is complementary to a nearby rRNA methylation site and is partially responsible for methylation of G2396. Both of these motifs are required for proper and efficient pre-rRNA processing. Finally, we show that SnoR28.1s genetically interact with HIDDEN TREASURE2 and NUCLEOLIN1. Our results advance our understanding of the roles of snoRNAs in Arabidopsis. [ABSTRACT FROM AUTHOR]

Simple Summary: The interaction between intestinal microbiota and host plays a key role in the development of intestinal diseases. Salmonella enteritidis infection is a common cause of human gastroenteritis, which can lead to gastrointestinal dysfunction and microecological disorder. It is an important public health problem all over the world. Lactic acid bacteria are among the main probiotics in the intestinal microbiota, which is one of the main defense lines against intestinal pathogens. It is now also considered to be an effective alternative antibiotic to fight pathogenic bacterial infections. In order to explore the potential mechanism of lactic acid bacteria against S. enteritidis infection, this study started from the perspective of lactic acid bacteria regulating the intestinal microbiota and the infection of antigenic bacteria. The probiotic strain Lactobacillusreuteri S5 (L. reuteri S5) was used to establish an animal model of S. enteritidis infection in broilers. The regulatory effect of L.reuteri S5 on the intestinal microbiota structure of chickens infected with S. enteritidis is studied by high throughput sequencing technology. The results showed that L. reuteri S5 could regulate the composition and abundance of intestinal microbiota and resist the infection of S. enteritidis. To understand the mechanism of lactic acid bacteria against Salmonella enteritidis infection; we examined how lactic acid bacteria regulated the intestinal microbiota to resist infection by pathogenic bacteria. The probiotic strain Lactobacillus reuteri S5 was used to construct an animal model of S. enteritidis infected broilers. A high-throughput sequencing technology was used to analyze the regulatory effects of L. reuteri S5 on the structure of the intestinal microbiota of broilers infected with S. enteritidis; and to examine the possible defense mechanism they used. Our results showed that the administration of L. reuteri S5 reduced colonization of S. enteritidis (p < 0.05), decreased intestinal permeability (p < 0.05), and reduced the bacterial displacement likely due by S. enteritidis colonization (p < 0.05), suggesting some enhancement of the intestinal barrier function. Furthermore, L. reuteri S5 increased the number of operational taxonomic units (OTUs) in the chicken cecal microflora and the relative abundance of Lactobacillaceae and decreased the relative abundance of Enterobacteriaceae. These results suggest that the lactic acid bacterium L. reuteri S5 protected the intestinal microbiota of chickens against S. enteritidis infection. [ABSTRACT FROM AUTHOR]

Single‐atom catalysts (SACs), as promising alternatives to Pt‐based catalysts, suffer from the limited choice of center metals and low single‐atom loading. Here, we report a pentacoordinated Zr‐based SAC with nontrivial axial O ligands (denoted O−Zr−N−C) for oxygen reduction reaction (ORR). The O ligand downshifts the d‐band center of Zr and confers Zr sites with stable local structure and proper adsorption capability for intermediates. Consequently, the ORR performance of O−Zr−N−C prominently surpasses that of commercial Pt/C, achieving a half‐wave potential of 0.91 V vs. reversible hydrogen electrode and outstanding durability (92 % current retention after 130‐hour operation). Moreover, the Zr site shows good resistance towards aggregation, enabling the synthesis of Zr‐based SAC with high loading (9.1 wt%). With the high‐loading catalyst, the zinc‐air battery (ZAB) delivers a record‐high power density of 324 mW cm−2 among those of SAC‐based ZABs. [ABSTRACT FROM AUTHOR]

Single‐atom catalysts (SACs), as promising alternatives to Pt‐based catalysts, suffer from the limited choice of center metals and low single‐atom loading. Here, we report a pentacoordinated Zr‐based SAC with nontrivial axial O ligands (denoted O−Zr−N−C) for oxygen reduction reaction (ORR). The O ligand downshifts the d‐band center of Zr and confers Zr sites with stable local structure and proper adsorption capability for intermediates. Consequently, the ORR performance of O−Zr−N−C prominently surpasses that of commercial Pt/C, achieving a half‐wave potential of 0.91 V vs. reversible hydrogen electrode and outstanding durability (92 % current retention after 130‐hour operation). Moreover, the Zr site shows good resistance towards aggregation, enabling the synthesis of Zr‐based SAC with high loading (9.1 wt%). With the high‐loading catalyst, the zinc‐air battery (ZAB) delivers a record‐high power density of 324 mW cm−2 among those of SAC‐based ZABs. [ABSTRACT FROM AUTHOR]