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Herein, sulfur vacancies in magnetic greigite (SVs-Fe3S4) nanosheets were synthesized by a one-step solvothermal method by adjusting the ethylene glycol: water ratio. Electron paramagnetic resonance spectroscopy (EPR) and X-ray photoelectron spectroscopy (XPS) revealed that SV-rich Fe3S4 and SV-poor Fe3S4 were acquired using 100% ethylene glycol and 100% water as solvent, respectively. A peroxidase-like activity assay demonstrated that maximum reaction rates for H2O2-mediated oxidation of 3,3',5,5'-tetramethyl-benzidine (TMB) catalyzed by the SV-rich Fe3S4 was 2.3 times higher than SV-poor Fe3S4. Density functional theory (DFT) calculations and reactive oxygen species (ROS) detection confirmed that the enhanced peroxidase-like activity by SV-rich Fe3S4 was attributed to efficient adsorption of H2O2 and subsequent decomposition to hydroxyl radicals (•OH) on the SVs sites of Fe3S4. The SV-rich Fe3S4 nanozyme was employed to develop a simple, highly sensitive and selective assay for glucose detection with a linear range of 0.5-150 μM and a detection limit of 0.1 μM (S/N = 3). A smartphone application (App) was designed and applied to efficiently detect serum glucose with the integrated analytical system based on the SV-rich Fe3S4. These new findings highlight the important role of surface defects in nanozymes on generating peroxidase-like activity for glucose detection in point-of-care diagnosis.

A sustained load holding period imposed during fatigue loading is detrimental to material performances, causing a sharp decline in the fatigue life of near-α titanium alloys. Therefore, the deformation discrepancies of dwell fatigue (DF) and low cycle fatigue (LCF) were studied for Ti834 titanium alloy with bimodal structures in this work. The fractographies after dwell fatigue and low cycle fatigue testing were characterized using scanning electron microcopy (SEM), and the crack propagation paths at the subsurface were investigated using an optical microscope (OM). In order to reveal the mechanism of fatigue damage, detailed dislocation structures were observed using transmission electron microcopy (TEM). The crack propagation paths in microscales and the dislocation distributions were observed in the LCF and DF. The reasons for the discrepancies are also discussed in this work, which effectively enhances the understanding of the dwell failure procedures. The results show that the near basal cracks are formed under dwell fatigue, and the deformation is highly localized at the boundary of αp grains under dwell fatigue. In contrast, during low cycle fatigue, the sample tends to deform homogenously. An intergranular fracture along the primary αp grains is formed due to the localized deformation during dwell fatigue. However, a transgranular fracture is formed in the primary αp grains under low cycle fatigue. [ABSTRACT FROM AUTHOR]

Light harvesting, separation of charge carriers, and surface reactions are three fundamental steps that are essential for an efficient photocatalyst. Here we show that these steps in the TiO2 can be boosted simultaneously by disorder engineering. A solid-state reduction reaction between sodium and TiO2 forms a core-shell c-TiO2@a-TiO2-x(OH)y heterostructure, comprised of HO-Ti-[O]-Ti surface frustrated Lewis pairs (SFLPs) embedded in an amorphous shell surrounding a crystalline core, which enables a new genre of chemical reactivity. Specifically, these SFLPs heterolytically dissociate dihydrogen at room temperature to form charge-balancing protonated hydroxyl groups and hydrides at unsaturated titanium surface sites, which display high reactivity towards CO2 reduction. This crystalline-amorphous heterostructure also boosts light absorption, charge carrier separation and transfer to SFLPs, while prolonged carrier lifetimes and photothermal heat generation further enhance reactivity. The collective results of this study motivate a general approach for catalytically generating sustainable chemicals and fuels through engineered disorder in heterogeneous CO2 photocatalysts. Developing an efficient photocatalyst for CO2 reduction is appealing. Here, the authors report a core-shell c-TiO2@a-TiO2-x(OH)y heterostructure with surface frustrated Lewis pairs on amorphous shells which enables a new genre of chemical reactivity. [ABSTRACT FROM AUTHOR]

It has long been known that the thermal catalyst Cu/ZnO/Al2O3(CZA) can enable remarkable catalytic performance towards CO2 hydrogenation for the reverse water-gas shift (RWGS) and methanol synthesis reactions. However, owing to the direct competition between these reactions, high pressure and high hydrogen concentration (≥75%) are required to shift the thermodynamic equilibrium towards methanol synthesis. Herein, a new black indium oxide with photothermal catalytic activity is successfully prepared, and it facilitates a tandem synthesis of methanol at a low hydrogen concentration (50%) and ambient pressure by directly using by-product CO as feedstock. The methanol selectivities achieve 33.24% and 49.23% at low and high hydrogen concentrations, respectively. Harsh reaction conditions are generally required for CO2 hydrogenation to shift the thermodynamic equilibrium towards methanol synthesis. Here, a new black indium oxide with two types of active sites, frustrated Lewis pairs and oxygen vacancies, is prepared, and facilitates a tandem synthesis of methanol at a low hydrogen concentration (50%) and ambient pressure. [ABSTRACT FROM AUTHOR]

Photocatalytic CO2 reduction (PCR) is able to convert solar energy into chemicals, fuels, and feedstocks, but limited by the deficiencies of photocatalysts in steering photon-to-electron conversion and activating CO2, especially in pure water. Here we report an efficient, pure water CO2-to-CO conversion photocatalyzed by sub-3-nm-thick BiOCl nanosheets with van der Waals gaps (VDWGs) on the two-dimensional facets, a graphene-analog motif distinct from the majority of previously reported nanosheets usually bearing VDWGs on the lateral facets. Compared with bulk BiOCl, the VDWGs-rich atomic layers possess a weaker excitonic confinement power to decrease exciton binding energy from 137 to 36 meV, consequently yielding a 50-fold enhancement in the bulk charge separation efficiency. Moreover, the VDWGs facilitate the formation of VDWG-Bi-VO••-Bi defect, a highly active site to accelerate the CO2-to-CO transformation via the synchronous optimization of CO2 activation, *COOH splitting, and *CO desorption. The improvements in both exciton-to-electron and CO2-to-CO conversions result in a visible light PCR rate of 188.2 μmol g−1 h−1 in pure water without any co-catalysts, hole scavengers, or organic solvents. These results suggest that increasing VDWG exposure is a way for designing high-performance solar-fuel generation systems. Efficient CO2 photoreduction in pure water remains challenging. Here, the authors propose to use van der Waals gaps-rich BiOCl atomic layers with low exciton binding energy and abundant surface oxygen vacancies for CO2 to CO conversion. [ABSTRACT FROM AUTHOR]

Background: The extra-articular lesions of rheumatoid arthritis (RA) are reported to involve multiple organs and systems throughout the body, including the heart, kidneys, liver, and lungs. This study assessed the potential causal relationship between RA and the risk of chronic kidney diseases (CKDs) using the Mendelian randomization (MR) analysis., Method: Independent genetic instruments related to RA and CKD or CKD subtypes at the genome-wide significant level were chosen from the publicly shared summary-level data of genome-wide association studies (GWAS). Then, we obtained some single-nucleotide polymorphisms (SNPs) as instrumental variables (IVs), which are associated with RA in individuals of European origin, and had genome-wide statistical significance (p5 × 10 -8 ). The inverse-variance weighted (IVW) method was the main analysis method in MR analysis. The other methods, such as weighted median, MR-Egger, simple mode, and weighted mode were used as supplementary sensitivity analyses. Furthermore, the levels of pleiotropy and heterogeneity were assessed using Cochran's Q test and leave-one-out analysis. Furthermore, the relevant datasets were obtained from the Open GWAS database., Results: Using the IVW method, the main method in MR analysis, the results showed that genetically determined RA was associated with higher risks of CKD [odds ratio (OR): 1.22, 95% confidence interval (CI) 1.13-1.31; p  < 0.001], glomerulonephritis (OR: 1.23, 95% CI 1.15-1.31; p < 0.000), amyloidosis (OR = 1.43, 95% CI 1.10-1.88, p  < 0.001), and renal failure (OR = 1.18, 95% CI 1.00-1.38, p  < 0.001). Then, using multiple MR methods, it was confirmed that the associations persisted in sensitivity analyses, and no pleiotropy was detected., Conclusion: The findings revealed a causal relationship between RA and CKD, including glomerulonephritis, amyloidosis, and renal failure. Therefore, RA patients should pay more attention to monitoring their kidney function, thus providing the opportunity for earlier intervention and lower the risk of progression to CKDs., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Jiang, Chen, Liu, Qi, Wang, Li, Jiang, Zhang, Huang, Mao and Ying.)

Photocatalytic CO 2 reduction (PCR) is able to convert solar energy into chemicals, fuels, and feedstocks, but limited by the deficiencies of photocatalysts in steering photon-to-electron conversion and activating CO 2 , especially in pure water. Here we report an efficient, pure water CO 2 -to-CO conversion photocatalyzed by sub-3-nm-thick BiOCl nanosheets with van der Waals gaps (VDWGs) on the two-dimensional facets, a graphene-analog motif distinct from the majority of previously reported nanosheets usually bearing VDWGs on the lateral facets. Compared with bulk BiOCl, the VDWGs-rich atomic layers possess a weaker excitonic confinement power to decrease exciton binding energy from 137 to 36 meV, consequently yielding a 50-fold enhancement in the bulk charge separation efficiency. Moreover, the VDWGs facilitate the formation of VDWG-Bi-V O •• -Bi defect, a highly active site to accelerate the CO 2 -to-CO transformation via the synchronous optimization of CO 2 activation, *COOH splitting, and *CO desorption. The improvements in both exciton-to-electron and CO 2 -to-CO conversions result in a visible light PCR rate of 188.2 μmol g -1 h -1 in pure water without any co-catalysts, hole scavengers, or organic solvents. These results suggest that increasing VDWG exposure is a way for designing high-performance solar-fuel generation systems., (© 2021. The Author(s).)

Objective: To analyze the factors that affect oculomotor nerve function recovery time in patients receiving balloon embolization for oculomotor nerve palsy caused by traumatic carotid cavernous sinus fistula., Methods: The clinical data were collected from 87 patients undergoing balloon embolization for oculomotor nerve palsy due to traumatic carotid cavernous sinus fistula from July 2005 to July 2013 and the factors affecting oculomotor nerve function recovery time was analyzed using a self-made questionnaire., Results and Conlusion: Oculomotor nerve function recovery time ranged from 1 to 6 months (mean 33.32 ± 16.76 days) in these patients. Age, severity of preoperative oculomotor nerve paralysis, injury-to-treatment time, and number of balloon used were positively correlated with nerve function recovery time, and the flow volume of traumatic carotid cavernous sinus fistula was negatively correlated with the recovery time.