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Enhancing the incorporation of highly accessible Lewis acid sites on fillers is crucial for achieving exceptional electrochemical performances in composite solid electrolytes (CSEs). Typically, they can provide a vital role in improving CSEs performance by interacting with lithium salt anions and the polymer matrix through Lewis acid–base interactions. To address this technological need, in this work, a novel filler of bimetallic UiO‐66(Zr/Ti)‐ionic liquid grafted composite (BUIL) is developed to enhance its inherent electrochemical properties. The bimetallic structure, which introduces structural defects, along with the grafted ionic liquid, abundantly creates accessible Lewis acid sites. This modification of the intrinsic Lewis acidity results in a remarkable enhancement of CSEs performances. The incorporation of BUIL in CSEs leads to a significant increase in ionic conductivity (0.458 mS cm−1) and lithium‐ion transference number (0.668) at 30 °C. Furthermore, LiFePO4/CSEs/Li cells demonstrate a high specific capacity of 148.5 mAh g−1 at a current density of 1 C, which is stably maintained over 880 cycles. Overall, the innovative synthetic approach in producing multifunctional fillers for CSEs shows strong potential for enhancing the performance of advanced lithium metal batteries. [ABSTRACT FROM AUTHOR]

O3-type layered oxides are considered highly promising cathode materials for sodium-ion batteries owing to their notable specific capacities, high theoretical energy densities, and low costs. However, the applications of O3-type layered oxides are limited owing to their structural degradation during charge–discharge cycles and poor moisture stability, which negatively affect their performance and durability. Notably, surface modifications of these materials play a crucial role in mitigating these challenges by providing a protective layer safeguarding the cathode material. In this study, Na2MoO4 (NMO) was successfully coated onto the surface of Na(Ni1/3Fe1/3Mn1/3)O2 (NFM) using a polyvinylpyrrolidone (PVP)-assisted wet chemical method. Despite their low costs and good electrical conductivities, Mo-based coatings are yet to be explored as potential coating materials for O3-type layered oxide cathodes. Here, the main PVP chain facilitates the formation of a uniform NMO coating layer by effectively anchoring Mo6+ ions onto the surface of the (Ni1/3Fe1/3Mn1/3)C2O4·xH2O ((NFM)C2O4) precursor. The presence of the NMO nanocoating layer on the NFM surface was confirmed via various characterization techniques. The NMO-coated NFM exhibited notable improvements in electrochemical performance compared to pristine NFM. In addition, the NMO-coated NFM exhibited superior moisture stability. This study presents an effective strategy to simultaneously improve the electrochemical performance and moisture stability of O3-type layered cathodes for sodium-ion batteries. [ABSTRACT FROM AUTHOR]

The superior optical properties of colloidal quantum dots (QDs) have garnered significant broad interest from academia and industry owing to their successful application in self‐emitting QD‐based light‐emitting diodes (QLEDs). In particular, active research is being conducted on QLEDs with top‐emission device architectures (TQLEDs) owing to their advantages such as easy integration with conventional backplanes, high color purity, and excellent light extraction. However, due to the complicated optical phenomena and their highly sensitive optoelectrical properties to experimental variations, TQLEDs cannot be optimized easily for practical use. This review summarizes previous studies that have investigated top‐emitting device structures and discusses ways to advance the performance of TQLEDs. First, theories relevant to the optoelectrical properties of TQLEDs are introduced. Second, advancements in device optimization are presented, where the underlying theories for each are considered. Finally, multilateral strategies for TQLEDs to enable their wider application to advanced industries are discussed. This work believes that this review can provide valuable insights for realizing commercial TQLEDs applicable to a broad range of applications. [ABSTRACT FROM AUTHOR]

Background Characterization of longitudinal SARS-CoV-2-specific antibody responses in children following infection and vaccination is needed to inform SARS-CoV-2 vaccine policy decisions for children, which may differ from adults. Methods We enrolled individuals at the time of SARS-CoV-2 infection or vaccination for longitudinal serological testing and compared SARS-CoV-2-spike-specific IgG and neutralization activity in children and adults stratified by infection and vaccination status using enzyme-linked immunosorbent and virus neutralization assays. Results Between June 2020 and December 2022, we collected sera from 669 participants aged 40 days to 55 years, including 330 unvaccinated individuals with laboratory-confirmed SARS-CoV-2 infection, 180 vaccinated SARS-CoV-2-naïve individuals, and 159 vaccinated previously infected individuals. Half (n = 330, 49.3%) were children. SARS-CoV-2-specific IgG and neutralization activity in children < 12 years old in response to infection persisted at higher levels than those of adults through at least 6 months (spike-specific IgG levels, 2.05 [95% CI: 1.4-3.1] times higher than adults; neutralizing activity, median 88.8 vs 75.2%, respectively, p  = .04). In addition, all pediatric participants had significantly higher IgG levels compared with adults at 6 months following infection or vaccination, regardless of prior infection status. Vaccine-induced SARS-CoV-2-specific IgG responses in previously infected individuals persisted at higher levels than those from infection alone at 6 months (median AUC, children 5-11 years old, 9115 vs 368; adolescents 3613 vs 475; adults 1956 vs 263, all p  < .001). Conclusions These data demonstrate the robust and persistent immunologic response of SARS-CoV-2 vaccination in children and emphasize the benefit of vaccination after SARS-CoV-2 infection. [ABSTRACT FROM AUTHOR]

Staphylococcus aureus is a commensal skin bacterium and a causative agent of infectious diseases. Biofilm formation in S. aureus is a mechanism that facilitates the emergence of resistant strains. This study proposes a mechanism for the regulation of biofilm formation in S. aureus through strain-specific physiological changes induced by the plant steroid diosgenin. A comparison of diosgenin-induced changes in the expression of regulatory genes associated with physiological changes revealed the intracellular regulatory mechanisms involved in biofilm formation. Diosgenin reduced biofilm formation in S. aureus ATCC 6538 and methicillin-resistant S. aureus (MRSA) CCARM 3090 by 39% and 61%, respectively. Conversely, it increased biofilm formation in S. aureus ATCC 29213 and MRSA CCARM 3820 by 186% and 582%, respectively. Cell surface hydrophobicity and extracellular protein and carbohydrate contents changed in a strain-specific manner in response to biofilm formation. An assessment of the changes in gene expression associated with biofilm formation revealed that diosgenin treatment decreased the expression of icaA and spa and increased the expression of RNAIII, agrA, sarA, and sigB in S. aureus ATCC 6538 and MRSA CCARM 3090; however, contrasting gene expression changes were noted in S. aureus ATCC 29213 and MRSA CCARM 3820. These results suggest that a regulatory mechanism of biofilm formation is that activated sigB expression sequentially increases the expression of sarA, agrA, and RNAIII. This increased RNAIII expression decreases the expression of spa, a surface-associated adhesion factor. An additional regulatory mechanism of biofilm formation is that activated sigB expression decreases the expression of an unknown regulator that increases the expression of icaA. This in turn decreases the expression of icaA, which decreases the synthesis of polysaccharide intercellular adhesins and ultimately inhibits biofilm formation. By assessing strain-specific contrasting regulatory signals induced by diosgenin in S. aureus without gene mutation, this study elucidated the signal transduction mechanisms that regulate biofilm formation based on physiological and gene expression changes. [ABSTRACT FROM AUTHOR]

In this study, nanosheet-like sorghum biomass is obtained by a mild alkaline treatment and high-energy ball milling. N, S co-doped hard carbon (NSSC) with the nanosheet morphology is subsequently synthesized by a direct-carbonization of the nanosheet-like sorghum biomass mixed with thiourea. NSSCs obtained at various annealing temperatures demonstrate that the optimal annealing temperature is necessary to balance the efficient heteroatom-doping and the level of carbonization. NSSC-600 obtained at the optimized annealing temperature of 600 °C presents a great K-ion storage performance as an anode material with a high reversible specific capacity of 268 mA h g−1 at 100 mA g−1 and outstanding stability over 2400 cycles. The effect of N and S heteroatom-doping on K-ion adsorption capacity is also verified by density functional theory (DFT) calculations. [ABSTRACT FROM AUTHOR]

Understanding how bike-share interacts with public transit is vital to determining the potential benefits of bike-share on the existing urban transportation system. This study examines the effects of bike-share users' socio-demographics and trip features on whether bike-share users integrate or substitute public transit by conducting a questionnaire survey of Seoul's bike-share users. The multinomial logistic model (MLM) was used for the statistical analysis. Our results showed that the bike-share's trip purpose and perceived utility are significantly associated with the modal integration and substitution between bike-share and public transit. In particular, bike-share users are more likely to integrate with public transit when they make utilitarian trips near public transit stations. Furthermore, those who substitute public transit intended to save travel costs and exercise. The study's findings can be utilized for establishing strategies to maximize the utility of bike-share in conjunction with the public transit system. [ABSTRACT FROM AUTHOR]