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Three-dimensional core–shell-structured TiO2@PPy/rGO nanocomposites were successfully constructed from TiO2@PPy nanospheres and graphene oxide via a polymerization method. First, TiO2 nanoparticles were uniformly coated with polypyrrole (PPy), forming core–shell TiO2@PPy nanospheres. The as-prepared TiO2@PPy nanospheres further self-assembled with graphene oxide (GO), resulting in the formation of three-dimensional ternary TiO2@PPy/rGO nanocomposites. Due to the strong interactions between TiO2@PPy and reduced graphene oxide (rGO), the three-dimensional TiO2@PPy/rGO electrode exhibited larger specific capacitance, lower charge transfer resistance, and more stable cycling performance compared to the TiO2@PPy nanospheres. More importantly, the existence of rGO increased the cycling stability of PPy and improved the capacitive performance, thus further demonstrating the positive effects of rGO, achieving a highest specific capacitance of 462.1 F g−1 at a current density of 0.5 A g−1. The present strategy will pave the way for the development of a new generation of advanced electrode materials for energy storage. [ABSTRACT FROM AUTHOR]

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Aims: To examine the association of weight status with the prevalence of blood pressure (BP), vital capacity, dental de-cay, and visual acuity among school-age children in Chengdu, China and to find the potential role of weight status to predict the common and frequently occurring diseases among school-age children. Methods: A cross-sectional study was conducted among 12,297 children aged 6-18 years from 10 schools in the Jinniu District of Chengdu, China. Body height, weight, waist circumference (WC), and BP were measured. Vital capacity, dental decay, and visual acuity were detected. Results: The overall prevalence of underweight, overweight, obesity, abdominal obesity, high BP, bad vital capacity weight index, dental decay, and low vision were 7.18, 13.47, 7.57, 18.90, 2.78, 21.93, 38.81, and 45.79%, respectively. After controlling for age, gender, and WC, it was found that overweight and obese children had a higher risk of developing high BP than normal weight children ([OR 4.20, p < 0.001] and [OR 8.76, p < 0.001], respectively), And adjusting forage, gender, and chest circumference, the risk of having bad vital capacity weight index among children with overweight and obesity was higher ([OR 2.15, p < 0.001] and [OR 5.40, p < 0.001], respectively), and the risk with underweight was lower (OR0.35, p < 0.001 ). After eliminating the influential factors of gender and age, children who were underweight were 1.16 times (OR 1.16, p = 0.048) more likely to have caries than children with normal weight, but obese children were found to have a lower prevalence for dental cavities than children with normal weight (OR 0.79, p = 0.002). Underweight and obese children had a higher prevalence of low vision; the OR of the appearance of low vision was 1.21 (p = 0.016) for underweight children and 1.23 (p = 0.009) for obese children after adjusting the age and gender. Conclusions: Abnormal weight status among Chengdu urban school-age children was found to be a severe health problem, and it was strongly associated with BP, vital capacity, dental decay, and visual acuity. [ABSTRACT FROM AUTHOR]

Hybrid organic-inorganic perovskite materials have attracted extensive attention due to their impressive performance in photovoltaic devices. One-dimensional perovskite CH3NH3PbI3 nanomaterials, possessing unique structural features such as large surface-to-volume ratio, anisotropic geometry and quantum confinement, may have excellent optoelectronic properties, which could be utilized to fabricate high-performance photodetectors. However, in comparison to CH3NH3PbI3 thin films, reports on the fabrication of CH3NH3PbI3 nanowires for optoelectrical application are rather limited. Herein, a two-step spin-coating process has been utilized to fabricate pure-phase and single-crystalline CH3NH3PbI3 nanowires on a substrate without mesoporous TiO2 or Al2O3. The size and density of CH3NH3PbI3 nanowires can be easily controlled by changing the PbI2 precursor concentration. The as-prepared CH3NH3PbI3 nanowires are utilized to fabricate photodetectors, which exhibit a fairly high switching ratio of ~600, a responsivity of 55 mA/W, and a normalized detectivity of 0.5 × 1011 jones under 532 nm light illumination (40 mW/cm2) at a very low bias voltage of 0.1 V. The as-prepared perovskite CH3NH3PbI3 nanowires with excellent optoelectronic properties are regarded to be a potential candidate for high-performance photodetector application. [ABSTRACT FROM AUTHOR]

Zinc-ion capacitors (ZICs) have attracted great attention due to a series of advantages. However, the cathode materials are still the bottleneck for high-performance ZICs to be achieved. Therefore, ZIF-8-derived porous carbons are one of the most promising candidates but ZIF-8 nanoparticles with different sizes exhibited various electrochemical performances in ZICs. Herein, a series of monodispersed ZIF-8 nanoparticles are first prepared by a temperature-controlled process to fabricate the corresponding ZIF-8-based porous carbon nanoparticles with pre-designed sizes. The as-prepared materials have been tested as cathode materials in ZICs. Thus, their size effect allowed us to disclose its correlation with other factors such as ion transport/storage and capacitance. The results reveal that the optimal-sized porous carbon particles can effectively shorten the ion transport distance and accelerate the ion diffusion rate, resulting in lower electrical resistance, larger ion diffusion coefficients, and faster electron transport. The presented findings can facilitate the design of new advanced cathode materials paving the way for the development of high-performance cathode materials for ZICs in the future., (© 2024 Wiley‐VCH GmbH.)

Intrinsically disordered proteins (IDPs) are emerging therapeutic targets for human diseases. However, probing their transient conformations remains challenging because of conformational heterogeneity. To address this problem, we developed a biosensor using a point-functionalized silicon nanowire (SiNW) that allows for real-time sampling of single-molecule dynamics. A single IDP, N-terminal transactivation domain of tumor suppressor protein p53 (p53 TAD1 ), was covalently conjugated to the SiNW through chemical engineering, and its conformational transition dynamics was characterized as current fluctuations. Furthermore, when a globular protein ligand in solution bound to the targeted p53 TAD1 , protein-protein interactions could be unambiguously distinguished from large-amplitude current signals. These proof-of-concept experiments enable semiquantitative, realistic characterization of the structural properties of IDPs and constitute the basis for developing a valuable tool for protein profiling and drug discovery in the future.

The importance of selectively oxidizing aniline into value-added chemicals azoxybenzene and nitrobenzene is well-recognized in organic synthesis. However, the lack of control over selectivity and the complex synthesis of costly catalysts significantly hinder these reactions' industrial applications. In this work, an environmentally friendly approach was developed for the selective oxidization of substituted anilines. This method involves adjusting the strength of alkalinity with peroxide as the oxidant, without the addition of any metals or additives. A mild base (NaF) facilitated azoxybenzene formation, while a stronger base (NaOMe) enabled the synthesis of nitroaromatics. These protocols are user-friendly and scalable, accommodating various substitution patterns and functional groups, yielding products with high to excellent yields. The findings of this work present a framework for investigating base catalysis in organic synthesis and provide a viable and effective approach for selectively oxidizing aniline., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Unravelling the influence of strain and geometric effects on the electrochemical reduction of carbon dioxide (CO 2 RR) on Cu-based (or Pd-based) alloys remains challenging due to complex local microenvironment variables. Herein, we employ two PdCu alloys (nanoparticles and nanodendrites) to demonstrate how CO 2 RR selectivity can shift from CO to HCOO - . Despite sharing consistent phases, exposed crystal facets, and overall oxidative states, these alloys exhibit different local strain profiles due to their distinct geometries. By integrating experimental data, in-situ spectroscopy, and density functional theory calculations, we revealed that CO 2 prefers adsorption on tensile-strained areas with carbon-side geometry, following a *COOH-to-CO pathway. Conversely, on some compressive-strained regions induced by the dendrite-like morphology, CO 2 adopts an oxygen-side geometry, favoring an *OCHO-to-HCOO pathway due to the downshift of the d -band center. Notably, our findings elucidate a dominant *OCHO-to-HCOO - pathway in catalysts when featuring both adsorption geometries. This research provides a comprehensive model for local environment of bimetallic alloys, and establishes a clear relationship between the CO 2 RR pathway shift and variation in local strain environments of PdCu alloys., (© The Author(s) 2024. Published by Oxford University Press on behalf of China Science Publishing & Media Ltd.)

Malonic acid is an important dicarboxylic acid, which can be widely used in the fields of chemical industry, medicine and food. In this study, a recombinant Escherichia coli strain BL21(TPP) was constructed to synthesize malonate through overexpressing six genes of ppc , aspC , panD , pa0132 , yneI and pyc . Under shake flask fermentation conditons, strain BL21(TPP) produced 0.61 g/L malonic acid. In a 5 L fermentor, the production of malonic acid reached 3.32 g/L by using an intermittent feeding strategy. Next, a recombinant strain BL21(SCR) was constructed by fusional expression of ppc and aspC , as well as pa0132 and yneI , respectively. As a result, the production of malonic acid increased to 0.83 g/L at the shake flask level, which was a 36% increase over the starting strain BL21(TPP). Finally, the highest malonate production reached 5.61 g/L in a 5 L fermentor, which was a 69% increase over the starting strain BL21(TPP). Production of malonic acid by metabolically engineered E . coli provides a basis for further optimization, and may also serve as a reference for the biosynthesis of other dicarboxylic acids.