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Globally, the rollout of COVID‐19 vaccine had been faced with a significant barrier in the form of vaccine hesitancy. This study adopts a multi‐stage perspective to explore the prevalence and determinants of COVID‐19 vaccine hesitancy, focusing on their dynamic evolutionary features. Guided by the integrated framework of the 3Cs model (complacency, confidence, and convenience) and the EAH model (environmental, agent, and host), this study conducted three repeated national cross‐sectional surveys. These surveys carried out from July 2021 to February 2023 across mainland China, targeted individuals aged 18 and older. They were strategically timed to coincide with three critical vaccination phases: universal coverage (stage 1), partial coverage (stage 2), and key population coverage (stage 3). From 2021 to 2023, the surveys examined sample sizes of 29 925, 6659, and 5407, respectively. The COVID‐19 vaccine hesitation rates increased from 8.39% in 2021 to 29.72% in 2023. Urban residency, chronic condition, and low trust in vaccine developer contributed to significant COVID‐19 vaccine hesitancy across the pandemic. Negative correlations between the intensity of vaccination policies and vaccine hesitancy, and positive correlations between vaccine hesitancy and long COVID, were confirmed. This study provides insights for designing future effective vaccination programs for emerging vaccine‐preventable infectious X diseases. [ABSTRACT FROM AUTHOR]

Potassium–sulfur (K−S) batteries have attracted wide attention owing to their high theoretical energy density and low cost. However, the intractable shuttle effect of K polysulfides results in poor cyclability of K−S batteries, which severely limits their practical application. Herein, a bifunctional concentrated electrolyte (3 mol L−1 potassium bis(trifluoromethanesulfonyl)imide in ethylene carbonate (EC)) with high ionic conductivity and low viscosity is developed to regulate the dissolution behavior of polysulfides and induce uniform K deposition. The organic groups in the cathode electrolyte interphase layer derived from EC can effectively block the polysulfide shuttle and realize a "solid–liquid–solid" reaction mechanism. The KF‐riched solid‐electrolyte interphase inhibits K dendrite growth during cycling. As a result, the achieved K−S batteries display a high reversible capacity of 654 mAh g−1 at 0.5 A g−1 after 800 cycles and a long lifespan over 2000 cycles at 1 A g−1. [ABSTRACT FROM AUTHOR]

Summary: High‐frequency AC (HFAC) LCLC resonant inverter has recently received more and more attention in power distribution system (PDS) of intelligent vehicles. However, LCLC resonance complicates the design of a current control loop and can even threaten the stability and transient performance of PDS. Active damping (AD) strategies based on the feedback of a single filter voltage or current have been shown to be effective and cost‐efficient method for attenuating resonant spikes. In this paper, a notch filter‐based AD (NFAD) control strategy is proposed to improve the stability and transient performance of PDS for intelligent vehicles. By sensing and feeding back the output resonance current of LCLC resonant inverter, the NFAD control strategy is then formulated to emulate a virtual impedance in order to improve the system phase margin and crossover frequency. Hence, the proposed control strategy can not only suppress the LCLC double resonance peaks but also effectively improve the transient performance of resonant inverter while guaranteeing the stability of the system. Finally, an experimental prototype was established and tested to verify the effectiveness of the proposed control strategy with a rated output power of 130 W, an operation frequency of 25 kHz, and a sinusoidal output voltage of 28 V (rms). [ABSTRACT FROM AUTHOR]

Liver fibrosis is caused by chronic liver injury. There are limited treatments for it, and the pathogenesis is unclear. Therefore, there is an urgent need to explore the pathogenesis of liver fibrosis, and to try to identify new potential therapeutic targets. For this study we used the carbon tetrachloride abdominal injection induced liver fibrosis animal model in mice. Primary hepatic stellate cell isolation was performed by a density‐gradient separation method, and this was followed by immunofluorescence stain analyses. Signal pathway analysis was performed by dual‐luciferase reporter assay and western blotting. Our results showed that RUNX1 was upregulated in cirrhotic liver tissues compared with normal liver tissues. Besides, overexpression of RUNX1 caused more severe liver fibrosis lesions than control group under CCl4‐induced conditions. Moreover, α‐SMA expression in the RUNX1 overexpression group was significantly higher than in the control group. Interestingly, we found that RUNX1 could promote the activation of TGF‐β/Smads in a dual‐luciferase reporter assay. Thus we demonstrated that RUNX1 could be considered as a new regulator of hepatic fibrosis by activating TGF‐β/Smads signalling. Based on this, we concluded that RUNX1 may be developed as a new therapeutic target in the treatment of liver fibrosis in the future. In addition, this study also provides a new insight about the aetiology of liver fibrosis. [ABSTRACT FROM AUTHOR]

Room temperature sodium‐sulfur (RT Na‐S) batteries are highly competitive as potential energy storage devices. Nevertheless, their actually achieved reversible capacities are far below the theoretical value due to incomplete transformation of polysulfides. Herein, atomically dispersed Fe‐N/S active center by regulating the second‐shell coordinating environment of Fe single atom is proposed. The Fe−N4S2 coordination structure with enhanced local electronic concentration around the Fermi level is revealed via synchrotron radiation X‐ray absorption spectroscopy (XAS) and theoretical calculations, which can not only significantly promote the transformation kinetics of polysulfides, but induce uniform Na deposition for dendrite‐free Na anode. As a result, the obtained S cathode delivers a high initial reversible capacity of 1590 mAh g−1, nearly the theoretical value. This work opens up a new avenue to facilitate the complete transformation of polysulfides for RT Na‐S batteries. [ABSTRACT FROM AUTHOR]

In this paper, the mechanical behavior of 10 and 14 vol.% SiCp/Al composites was studied with both experiments and numerical analysis. A 3D macrostructure model based on modified Gurson–Tvergaard–Needleman (GTN) model was developed to predict the elasto‐plastic response and fracture behavior of particle reinforced aluminum matrix composites (PRAMCs). The particle size effects on the plastic strengthening induced by geometrically necessary dislocations (GNDs) were introduced, and the size distribution of the SiC particles was obtained according to the statistical analysis of the microstructure. The material parameters for GTN model were determined with a parameter identification process, and the validity of the numerical results was validated by the agreement of the experimental stress–strain curve. Results reveal that particle size randomness plays an important role in the fracture morphologies. Highlights: Establish a macro‐mechanical model to predict failure behavior of PRAMCs.Modify the GTN damage model to introduce the effect of particle failure and decohesion.Identify the parameters for the modified GTN model and validate the model by comparing with experimental results.Find that particle size randomness plays an important role in fracture morphologies. [ABSTRACT FROM AUTHOR]

Aerogels hold promises as lightweight replacements in various applications but are plagued by their fabrication equipment, such as supercritical dryers or lyophilizers that need to work under extreme conditions. This study presents a covalent chemistry approach to strengthen cellulose nanofibers (CNF) with carboxymethylated chitosan (CMCs) to produce aerogels by ambient drying. The cross‐linking and gelation of the CNF and CMCs solutions are triggered by a triazine derivative, 4‐(4,6‐Dimethoxy[1.3.5]triazin‐2‐yl)‐4‐methylmorpholinium chloride hydrate, to form an amide bond. This approach leads to robust hydrogels that can resist capillary force during the ambient volatilization process and are turned into aerogels by freezing, solvent thawing and exchange, and ambient drying. The lightweight aerogels exhibit desirable qualities, including superior mechanical performance, a low density of 12.0 mg cm−3, and low shrinkage of 10.1%. The presented CMCs/CNF aerogels can also serve as a helpful carrier for conductive polymer, poly (3,4‐ethylene dioxythiophene):tosylate, through in situ polymerization to demonstrate their applications. These conductive aerogels are used for high‐performance supercapacitors and moisture‐enabled electrical generators. This study provides inspiration and a reliable approach for the elaborately structural design of aerogels at ambient conditions and endows application prospects in energy storage and generation opportunities. [ABSTRACT FROM AUTHOR]

In recent years, with increasing demands for in vivo fluorescence imaging and photodynamic therapy, light in the second near‐infrared window (NIR‐II; 1000–1700 nm) has attracted tremendous interest because it offers numerous merits, including deep penetration, minimal phototoxicity, diminished tissue autofluorescence, and reduced tissue absorption and scattering. Among the diverse types of nanoparticles, organic nanoprobes with aggregation‐induced emission (AIE) characteristics have emerged as a better option owing to their ultra‐brightness, excellent photostability, low cytotoxicity, and tailorable optical properties. Recent efforts in the AIE realm have revealed advancements in molecular design for long wavelength absorption and multiphoton excitation, which efficiently modulate the working optical region to the NIR‐II region. In this review, the current status of AIE nanoprobes in the NIR‐II window is summarized. Starting with molecular design strategies, recent efforts in fluorescence imaging and photodynamic therapy are then discussed. Finally, perspectives and challenges in this newly emerging field are given. This review hopes to encourage more innovative ideas in material design and biomedical applications for promoting AIE nanoprobes for future clinical translation. [ABSTRACT FROM AUTHOR]

The size and structural control of particulate carriers for imaging agents and therapeutics are constant themes in designing smart delivery systems. This is motivated by the causal relationship between geometric parameters and functionalities of delivery vehicles. Here, both in vitro and in vivo, the controlling factors for cytotoxicity, photothermal, and anti‐tumor effects of biodegradable magnesium@poly(lactic‐co‐glycolic acid (Mg@PLGA) particulate carriers with different sizes and shell thicknesses are investigated. Mg@PLGA microspheres fabricated by microfluidic emulsification are shown to have higher Mg encapsulation efficiency, 87%, than nanospheres by ultrasonic homogenization, 50%. The photothermal and anti‐tumor effects of Mg@PLGA spheres are found to be dictated by their Mg content, irrelevant to size and structural features, as demonstrated in both in vitro cell assays and in vivo mice models. These results also provide important implications for designing and fabricating stimuli‐responsive drug delivery vehicles. [ABSTRACT FROM AUTHOR]

Sodium metal anodes are ideal candidates for advanced high energy density Na metal batteries. Nevertheless, the unstable solid electrolyte interphase (SEI), the uncontrollable dendrite growth, and low Coulombic efficiency during cycling have prevented their applications. Herein, a high‐performance Na anode is achieved by introduction of an ex situ artificial Na3P layer on the surface via a simple red phosphorus pretreatment method. The artificial SEI layer possesses high ionic conductivity and high Young's modulus, which regulates uniform deposition of ions and prevents the dendrite growth. Benefiting from these merits, the Na||Na cells with the protected layers demonstrate excellent electrochemical performance (780 h at 1.0 mA cm–2, 1.0 mAh cm–2). When assembled into a full battery with a Na3V2(PO4)3 cathode, the Na metal battery exhibits a long lifespan of 400 cycles at 15 C and a high rate capacity of ≈53.2 mAh g–1 at 30 C. In addition the red P pretreatment method can be applied to potassium metal anodes. Outstanding performance is also achieved in K||K cells with the formation of a KxPy protecting layer (550 h at 0.5 mA cm–2, 0.5 mAh cm–2). The artificial P‐derived protection approach can also be extended to solid‐state alkali metal batteries with high power density and energy density. [ABSTRACT FROM AUTHOR]