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Calcium silicate hydrate (C‐S‐H) synthesis follows multistep nucleation processes ranging from amorphous globules to nanocrystals. This type of nonclassical nucleation pathway attracts extensive interest and yet related molecular processes are mostly unexplored. Herein, atomic‐level structure evolution during this process is unveiled. From inside to outside of the globule, the atomic arrangement evolves from amorphous configuration to layered stacking of calcium silicate layers with layers spaced by 1.1 nm. Numerous cations surrounding the globules provide extra calcium ions to form nano C‐S‐H foils at the edge of the globule. The polymerization to form calcium silicate chains has almost been completed before 5 min reaction, and the C‐S‐H structure formation is basically based on the self‐assembly to be calcium silicate layers and then lamellar crystal inside the globule. Silicate chain defects inhibit a‐ and c‐axes crystallization, but promote b‐axes one, leading to anisotropic growth of crystalline C‐S‐H. The defects lead to the crystallization pathways conversion from Si–O–Si bonds formation to Ca2+ electrostatic linking. [ABSTRACT FROM AUTHOR]

Nanozymes have demonstrated significant potential in combating malignant tumor proliferation through catalytic therapy. However, the therapeutic effect is often limited by insufficient catalytic performance. In this study, we propose the utilization of strain engineering in metallenes to fully expose the active regions due to their ultrathin nature. Here, we present the first report on a novel tensile strain‐mediated local amorphous RhRu (la‐RhRu) bimetallene with exceptional intrinsic photothermal effect and photo‐enhanced multiple enzyme‐like activities. Through geometric phase analysis, electron diffraction profile, and X‐ray diffraction, it is revealed that crystalline‐amorphous heterophase boundaries can generate approximately 2 % tensile strain in the bimetallene. The ultrathin structure and in‐plane strain of the bimetallene induce an amplified strain effect. Both experimental and theoretical evidence support the notion that tensile strain promotes multiple enzyme‐like activities. Functioning as a tumor microenvironment (TME)‐responsive nanozyme, la‐RhRu exhibits remarkable therapeutic efficacy both in vitro and in vivo. This work highlights the tremendous potential of atomic‐scale tensile strain engineering strategy in enhancing tumor catalytic therapy. [ABSTRACT FROM AUTHOR]

Nanozymes have demonstrated significant potential in combating malignant tumor proliferation through catalytic therapy. However, the therapeutic effect is often limited by insufficient catalytic performance. In this study, we propose the utilization of strain engineering in metallenes to fully expose the active regions due to their ultrathin nature. Here, we present the first report on a novel tensile strain‐mediated local amorphous RhRu (la‐RhRu) bimetallene with exceptional intrinsic photothermal effect and photo‐enhanced multiple enzyme‐like activities. Through geometric phase analysis, electron diffraction profile, and X‐ray diffraction, it is revealed that crystalline‐amorphous heterophase boundaries can generate approximately 2 % tensile strain in the bimetallene. The ultrathin structure and in‐plane strain of the bimetallene induce an amplified strain effect. Both experimental and theoretical evidence support the notion that tensile strain promotes multiple enzyme‐like activities. Functioning as a tumor microenvironment (TME)‐responsive nanozyme, la‐RhRu exhibits remarkable therapeutic efficacy both in vitro and in vivo. This work highlights the tremendous potential of atomic‐scale tensile strain engineering strategy in enhancing tumor catalytic therapy. [ABSTRACT FROM AUTHOR]

As an environmentally friendly natural polymer, citric acid-modified chitosan (CAMC) can effectively regulate the hydration and exothermic processes of cement-based materials. However, the influence of CAMC on the macroscopic properties of concrete and the optimal dosage are still unclear. This work systematically investigates the effects of CAMC on the mixing performance, mechanical properties, shrinkage performance, and durability of concrete. The results indicated that CAMC has a thickening effect and prolongs the setting time of concrete. CAMC has a negative impact on the early strength of concrete, but it is beneficial for the development of the subsequent strength of concrete. With the increase in CAMC content, the self-shrinkage rate of concrete samples decreased from 86.82 to 14.52 με. However, the CAMC-0.6% sample eventually expanded, with an expansion value of 78.49 με. Moreover, the long-term drying shrinkage rate was decreased from 551.46 to 401.94 με. Furthermore, low-dose CAMC can significantly reduce the diffusion coefficient of chloride ions, improve the impermeability and density of concrete, and thereby enhance the freeze–thaw cycle resistance of concrete. [ABSTRACT FROM AUTHOR]

Despite the significant progress of blue perovskite light‐emitting diodes (PeLEDs) in recent years, huge challenges still remain in improving their efficiency and spectral stability. In this work, a new strategy is reported to realize efficient and spectral stable blue PeLEDs through synchronously optimizing light outcoupling and carrier recombination of perovskite films. By introducing additives in both precursor solution and antisolvent, the crystallization of the perovskite films is regulated, leading to a spontaneous formation of undulant morphology, which favorably enhances the light outcoupling efficiency. Meanwhile, the formation of low‐dimensional perovskite phases is suppressed, in accompany with a reduced defect density and accelerated energy transfer, leading to a rapid concentration of excitons in the target perovskite phases and a significant enhancement of radiative carrier recombination. Resultantly, the optimized blue perovskite films show a high photoluminescent quantum yield approaching 80%, and the corresponding optimized PeLEDs show a high external quantum efficiency (EQE) of 11.88%, which significantly outperforms the control device with only 1.96%. Importantly, the optimized perovskite films and PeLEDs also exhibit improved spectral stability. This work provides a new pathway toward realizing efficient and spectral‐stable PeLEDs via simultaneously tackling the issues of light outcoupling and carrier recombination in the devices. [ABSTRACT FROM AUTHOR]

Urea oxidation reaction (UOR) has garnered significant attention in recent years as a promising and sustainable clean‐energy technology. Urea‐containing wastewater poses severe threats to the environment and human health. Numerous studies hence focus on developing UOR as a viable process for simultaneously remediating wastewater and converting it into energy. Moreover, UOR, which has a thermodynamic potential of 0.37 V (vs reversible hydrogen electrode, RHE), shows great promise in replacing the energy‐intensive oxygen evolution reaction (OER; 1.23 V vs RHE). The versatility and stability of urea, particularly at ambient temperatures, make it an attractive alternative to hydrogen in fuel cells. Since UOR entails a complex intermediate adsorption/desorption process, many studies are devoted to designing cost‐effective and efficient catalysts. Notably, transition metal‐based materials with regulated d orbitals have demonstrated significant potential for the UOR process. However, comprehensive reviews focusing on transition metal‐based catalysts remain scarce. In light of this, the review aims to bridge the gap by offering an in‐depth and systematic overview of cutting‐edge design strategies for transition metal‐based catalysts and their diverse applications in UOR. Additionally, the review delves into the status quo and future directions, charting the course for further advancements in this exciting field. [ABSTRACT FROM AUTHOR]

Natural killer (NK) cells can migrate quickly to the tumor site to exert cytotoxic effects on tumors, and some chemokines, including CXCL8, CXCL10 or and CXCL12, can regulate the migration of NK cells. Activin A, a member of the transforming growth factor β (TGF-β) superfamily, is highly expressed in tumor tissues and involved in tumor development and immune cell activation. In this study, we focus on the effects of activin A on NK cell migration. In vitro, activin A induced NK cell migration and invasion, promoted cell polarization and inhibited cell adhesion. Moreover, activin A increased Ca2+, p-SMAD3 and p-AKT levels in NK cells. An AKT inhibitor and Ca2+ chelator partially blocked activin A-induced NK cell migration. In vivo, exogenous activin A increased tumor-infiltrating NK cells in NS-1 cell solid tumors and inhibited tumor growth, and blocking endogenous activin A with anti-activin A antibody reduced tumor-infiltrating NK cells in 4T-1 cell solid tumors. These results suggest that activin A induces NK cell migration through AKT signaling and calcium signaling and may enhance the antitumor effect of NK cells by increasing tumor-infiltrating NK cells. [ABSTRACT FROM AUTHOR]

Radiation-induced pulmonary fibrosis (RIPF) is a common side effect of radiation therapy for thoracic tumors without effective prevention and treatment methods at present. The aim of this study was to explore whether glycyrrhetinic acid (GA) has a protective effect on RIPF and the underlying mechanism. A RIPF mouse model administered GA was used to determine the effect of GA on RIPF. The cocultivation of regulatory T (Treg) cells with mouse lung epithelial-12 cells or mouse embryonic fibroblasts and intervention with GA or transforming growth factor-β1 (TGF-β1) inhibitor to block TGF-β1 was conducted to study the mechanism by which GA alleviates RIPF. Furthermore, injection of Treg cells into GA-treated RIPF mice to upregulate TGF-β1 levels was performed to verify the roles of TGF-β1 and Treg cells. GA intervention improved the damage to lung tissue structure and collagen deposition and inhibited Treg cell infiltration, TGF-β1 levels, epithelial mesenchymal transition (EMT), and myofibroblast (MFB) transformation in mice after irradiation. Treg cell-induced EMT and MFB transformation in vitro were prevented by GA, as well as a TGF-β1 inhibitor, by decreasing TGF-β1. Furthermore, reinfusion of Treg cells upregulated TGF-β1 levels and exacerbated RIPF in GA-treated RIPF mice. GA can improve RIPF in mice, and the corresponding mechanisms may be related to the inhibition of TGF-β1 secreted by Treg cells to induce EMT and MFB transformation. Therefore, GA may be a promising therapeutic candidate for the clinical treatment of RIPF. [ABSTRACT FROM AUTHOR]

Present work demonstrate an efficient strategy of regulating the molecular conformation in PEDOT:PSS for ordered PEDOT domains and favorable band alignment, leading to the formation of true-blue PeLEDs with peak EQE up to 6.86% and maximum luminance of 854.10cd/m2 at wavelength of 478 nm. And we achieved the success of air-processed blue PeLEDs based on PFOA modified PEDOT:PSS. [Display omitted] • PFOA regulates the molecular conformation of PEDOT:PSS, improving carrier transport and alignment with the perovskite layer. • The PeLEDs with PFOA reach a peak external quantum efficiency of 6.86 % and a maximum luminance of 854.10 cd/m2 at a wavelength of 478 nm, which are the record values for the pure-bromide quasi-2D PeLEDs in the true-blue region. • The blue PeLEDs were successfully fabricated under ambient conditions (≈25 % RH and 20 °C), owing to the hydrophobic fluorine-carbon (C-F) chains of PFOA. The pure-bromide quasi-2D perovskite has shown advantages in fabrication of blue perovskite light-emitting diodes (PeLEDs) due to its relatively good color stability and capability of moisture resistance. However, the performances of efficiency and luminance of pure-bromide quasi-2D PeLEDs with true-blue (470 nm−480 nm) emission are still inferior. Here, we show a interfacial modification strategy of involving perfluorooctanoic acid (PFOA) to a hole transport layer of poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS), to improve the performances of the true-blue PeLEDs. The PFOA regulates the molecular conformation of PEDOT:PSS, forming ordered PEDOT domains that improves the carrier transport and a more favorable band alignment with the perovskite emissive layers. The achieved true-blue PeLEDs show peak EQE of 6.86 % and maximum luminance of 854.10 cd/m2 at wavelength of 478 nm, which are the record values for the pure-bromide quasi-2D PeLEDs in true-blue region. Moreover, owing to the hydrophobic fluorine-carbon (C-F) chains of PFOA, we successfully fabricate the blue PeLEDs in air condition without inert gas protection. This work paves the way for commercial applications in next-generation display technologies. [ABSTRACT FROM AUTHOR]

Abscisic acid-, stress-, and ripening-induced (ASR) proteins in plants play a significant role in plant response to diverse abiotic stresses. However, the functions of ASR genes in maize remain unclear. In the present study, we identified a novel drought-induced ASR gene in maize (ZmASR1) and functionally characterized its role in mediating drought tolerance. The transcription of ZmASR1 was upregulated under drought stress and abscisic acid (ABA) treatment, and the ZmASR1 protein was observed to exhibit nuclear and cytoplasmic localization. Moreover, ZmASR1 knockout lines generated with the CRISPR–Cas9 system showed lower ROS accumulation, higher ABA content, and a higher degree of stomatal closure than wild-type plants, leading to higher drought tolerance. Transcriptome sequencing data indicated that the significantly differentially expressed genes in the drought treatment group were mainly enriched in ABA signal transduction, antioxidant defense, and photosynthetic pathway. Taken together, the findings suggest that ZmASR1 negatively regulates drought tolerance and represents a candidate gene for genetic manipulation of drought resistance in maize. • A novel ASR gene was firstly cloned and characterize from maize. • ZmASR1 knockout lines showed enhanced drought stress tolerance in maize. • ZmASR1 knockout lines showed altered the expression of stress-response related genes. [ABSTRACT FROM AUTHOR]

[Display omitted] • The δ-MnO 2 /Ti 3 C 2 T x cathode was prepared by a mild one-step in-situ growth strategy. • The δ-MnO 2 /Ti 3 C 2 T x cathode has a high specific capacity of 320.6 mAh g−1 at 0.1 A g−1. • The Ti 3 C 2 T x scaffolds suppress the irreversible structural damage of δ-MnO 2. • The Ti 3 C 2 T x nanosheets constitute an efficient continuous electron transport pathway. Manganese-based oxides are deemed to be prospective cathode materials for aqueous zinc-ion batteries (ZIBs). Nevertheless, their practical application was hampered by the slow zinc-ion diffusion dynamics and the instability of MnO 2 structure. The δ-MnO 2 /MXene cathodes have been investigated to overcome the inherent defects of δ-MnO 2 and significantly improve the performance of ZIBs. However, these δ-MnO 2 /MXene cathodes suffer from high-temperature, high-pressure, time-consuming or complicated production processes. To address these issues, δ-MnO 2 /Ti 3 C 2 T x cathode was synthesized by a one-step in-situ growth strategy under mild conditions. The δ-MnO 2 /Ti 3 C 2 T x cathode can take advantages of the large specific capacity of δ-MnO 2 and the high conductivity of Ti 3 C 2 T x nanosheets. Besides, the highly conductive Ti 3 C 2 T x scaffolds efficaciously suppress the irreversible structural damage of δ-MnO 2. Therefore, the ZIB assembled with the δ-MnO 2 /Ti 3 C 2 T x cathode demonstrates significantly improved electrochemical behavior with a large specific capacity of 320.6 mAh g−1 at 0.1 A g−1, excellent rate capability of 153.0 mAh g−1 at 3.0 A g−1, high energy density of 440.0 Wh kg−1 at 136.6 W kg−1, and good cyclability with a capacity retention of 70.2 % after 1500 cycles, significantly outperforming the δ-MnO 2 cathode. The findings of this study suggest that the δ-MnO 2 /Ti 3 C 2 T x composite holds promise as a potential cathode for high-performance aqueous ZIBs. [ABSTRACT FROM AUTHOR]

Taurine (3S) inhibits heat-induced Ostwald ripening by binding to perovskite. 3, 3-diphenylpropylamine (DPPA) improves hydrophobicity to suppresses moisture-induced phase disproportionation. As a result, perovskite films with 3S and DPPA maintain stability for over 200h at 70 °C and over 310 h at 20% relative humidity, achieving the most stable blue quasi-2D perovskite emitters. [Display omitted] • Studying the optical property evolution of blue perovskite under stimuli of moisture and heat. • Proposing a strategy to curb Ostwald ripening and phase disproportionation in blue perovskite. • Achieving one of the most stable blue perovskite films under stimuli of moisture and heat. Quasi-2D metal halide perovskite is rising for efficient blue light-emitting diodes due to strong quantum confinement and tunable emission, while a challenge remains in its poor stability of n -phase distribution under external stresses. Herein, the stable blue quasi-2D perovskite under heat and moisture conditions is achieved by dual ligand engineering. The Lewis base moieties − SO 3 − from taurine (3S) bind tightly with perovskite edges, inhibiting Ostwald ripening of the perovskite phase caused by the heat, and 3, 3-diphenylpropylamine (DPPA) provides a strong hydrophobicity to the perovskite film, suppressing phase disproportionation induced by the moisture. Accordingly, the blue perovskite film, modified synergistically by the 3S and DPPA dual ligands, maintains its initial photoluminescence quantum yield (PLQY) after over 200 h with 70 °C heating, and only exhibiting a redshift in PL peak wavelength less than 10 nm. Exposing under environment condition of 20 % relative humidity for 300 h, the blue perovskite film still retains its initial PL peak wavelength with PLQY exceeding 50 % of the initial value. This achievement establishes a notable strategy for enhancing both the thermal and moisture stability of blue quasi-2D perovskite. Furthermore, the light-emitting diodes based on the perovskite films display the enhanced operating stability. This work offers an efficient strategy for stabilizing blue quasi-2D perovskite and the corresponding devices for the display application. [ABSTRACT FROM AUTHOR]