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The Sentinel-2 Multi-Spectral Instrument (MSI) is characterized by short revisit times (5 days), red-edge spectral bands (665 nm and 705 nm), and a high spatial resolution (10 m), making it highly suitable for monitoring water quality in both inland and coastal waters. Unlike SeaWiFS, which can adjust its viewing angles to minimize sunglint, the Sentinel-2 MSI operates with fixed near-nadir angles, which makes it more susceptible to sunglint. Additionally, the complex optical properties of water pose challenges in accurately determining its water-leaving reflectance. Therefore, we compared the effectiveness of six atmospheric correction (AC) algorithms (POLYMER, MUMM, DSF, C2RCC, BP, and GRS) in correcting sunglint using two typical lakes in Xinjiang, China, as examples. The results indicated that POLYMER achieved the highest overall evaluation score (1.61), followed by MUMM (1.21), while BP exhibited the lowest performance (0.62). Specifically, POLYMER showed robust performance at the 665 nm band with RMSE = 0.0012 sr−1, R2 = 0.74, and MAPE = 30.68%, as well as at the 705 nm band with RMSE = 0.0014 sr−1, R2 = 0.42, and MAPE = 38.44%. At the 443, 490, and 560 nm bands, MUMM showed better performance (RMSE ≤ 0.0026 sr−1, R2 ≥ 0.86, MAPE ≤ 28.20%). In terms of band ratios, POLYMER exhibited the highest accuracy (RMSE ≤ 0.093 and MAPE ≤ 22.2%), particularly for the ratio Rrs(490)/Rrs(560) (R2 = 0.71). In general, POLYMER is the best choice for the sunglint correction of Xinjiang's clean lakes. This study assessed the capability of different AC algorithms for sunglint correction and enhanced the monitoring capability of MSI data in clean waters. [ABSTRACT FROM AUTHOR]

Directly coupling N2 and CO2 to synthesize urea by photocatalysis paves a sustainable route for urea synthesis, but its performance is limited by the competition of photogenerated electrons between N2 and CO2, as well as the underutilized photogenerated holes. Herein, we report an efficient urea synthesis process involving photogenerated electrons and holes in respectively converting CO2 and N2 over a redox heterojunction consisting of WO3 and Ni single‐atom‐decorated CdS (Ni1‐CdS/WO3). For the photocatalytic urea synthesis from N2 and CO2 in pure water, Ni1‐CdS/WO3 attained a urea yield rate of 78 μM h−1 and an apparent quantum yield of 0.15 % at 385 nm, which ranked among the best photocatalytic urea synthesis performance reported. Mechanistic studies reveal that the N2 was converted into NO species by ⋅OH radicals generated from photogenerated holes over the WO3 component, meanwhile, the CO2 was transformed into *CO species over the Ni site by photogenerated electrons. The generated NO and *CO species were further coupled to form *OCNO intermediate, then gradually transformed into urea. This work emphasizes the importance of reasonably utilizing photogenerated holes in photocatalytic reduction reactions. [ABSTRACT FROM AUTHOR]

Directly coupling N2 and CO2 to synthesize urea by photocatalysis paves a sustainable route for urea synthesis, but its performance is limited by the competition of photogenerated electrons between N2 and CO2, as well as the underutilized photogenerated holes. Herein, we report an efficient urea synthesis process involving photogenerated electrons and holes in respectively converting CO2 and N2 over a redox heterojunction consisting of WO3 and Ni single‐atom‐decorated CdS (Ni1‐CdS/WO3). For the photocatalytic urea synthesis from N2 and CO2 in pure water, Ni1‐CdS/WO3 attained a urea yield rate of 78 μM h−1 and an apparent quantum yield of 0.15 % at 385 nm, which ranked among the best photocatalytic urea synthesis performance reported. Mechanistic studies reveal that the N2 was converted into NO species by ⋅OH radicals generated from photogenerated holes over the WO3 component, meanwhile, the CO2 was transformed into *CO species over the Ni site by photogenerated electrons. The generated NO and *CO species were further coupled to form *OCNO intermediate, then gradually transformed into urea. This work emphasizes the importance of reasonably utilizing photogenerated holes in photocatalytic reduction reactions. [ABSTRACT FROM AUTHOR]

The key to designing photocatalysts is to orient the migration of photogenerated electrons to the target active sites rather than dissipate at inert sites. Herein, we demonstrate that the doping of phosphorus (P) significantly enriches photogenerated electrons at Ni active sites and enhances the performance for CO2 reduction into syngas. During photocatalytic CO2 reduction, Ni single‐atom‐anchored P‐modulated carbon nitride showed an impressive syngas yield rate of 85 μmol gcat−1 h−1 and continuously adjustable CO/H2 ratios ranging from 5:1 to 1:2, which exceeded those of most of the reported carbon nitride‐based single‐atom catalysts. Mechanistic studies reveal that P doping improves the conductivity of catalysts, which promotes photogenerated electron transfer to the Ni active sites rather than dissipate randomly at low‐activity nonmetallic sites, facilitating the CO2‐to‐syngas photoreduction process. [ABSTRACT FROM AUTHOR]

Objective: This study aims to conduct an in-depth genomic analysis of a carbapenem-resistant Proteus mirabilis strain to uncover the distribution and mechanisms of its resistance genes. Methods: The research primarily utilized whole-genome sequencing to analyze the genome of the Proteus mirabilis strain. Additionally, antibiotic susceptibility tests were conducted to evaluate the strain's sensitivity to various antibiotics, and related case information was collected to analyze the clinical distribution characteristics of the resistant strain. Results: Study on bacterial strain WF3430 from a tetanus and pneumonia patient reveals resistance to multiple antibiotics due to extensive use. Whole-genome sequencing exposes a 4,045,480 bp chromosome carrying 29 antibiotic resistance genes. Two multidrug-resistant (MDR) gene regions, resembling Tn6577 and Tn6589, were identified (MDR Region 1: 64.83 Kb, MDR Region 2: 85.64 Kbp). These regions, consist of integrative and conjugative elements (ICE) structures, highlight the intricate multidrug resistance in clinical settings. Conclusion: This study found that a CR-PMI strain exhibits a unique mechanism for acquiring antimicrobial resistance genes, such as blaNDM−1, located on the chromosome instead of plasmids. According to the results, there is increasing complexity in the mechanisms of horizontal transmission of resistance, necessitating a comprehensive understanding and implementation of targeted control measures in both hospital and community settings. [ABSTRACT FROM AUTHOR]

Optically active poly(naphthalene‐1,4‐diyl) was prepared through helix–sense–selective polymerization of the corresponding monomers and also through circularly polarized light (CPL) irradiation, resulting in distinctive circular dichroism (CD) spectral patterns. Chirality of the helix–sense–selective polymerization ‐based polymer is ascribed to preferred–handed helicity while that of the CPL–based polymer to a non–helical, chiral conformation ('biased–dihedral conformation') with preferred–handedness which was stable only in the solid state. The helix of the helix–sense–selective polymerization–based polymer gradually racemized in tetrahydrofuran while it was stabilized by aggregate formation in a hexane–dichloromethane solution. Both helix–sense–selective polymerization‐ and CPL–based polymers exhibited efficient circularly polarized luminescence. [ABSTRACT FROM AUTHOR]

Soil salinity significantly reduces soybean (Glycine max L.) production worldwide. Plants resistance to stress conditions is a complex characteristic regulated by multiple signaling pathways. The v-Myb avian myeloblastosis viral oncogene homolog (MYB) transcription factor (TF) plays a crucial role in plant development, secondary metabolism, and abiotic stress responses. GmMYB68-overexpression and RNA interference (RNAi) lines were established for examining the function of G. max GmMYB68 in plant responses to abiotic stresses. The predicted amino acid sequence of GmMYB68 was similar to that of R2R3-MYB proteins. Quantitative real-time PCR analysis revealed that GmMYB68 expression varied in response to abiotic stresses. GmMYB68-overexpression lines showed enhanced resistance to salt and alkali stresses and their osmotic adjustment and photosynthetic rates were also stronger than that of GmMYB68-RNAi and wild type plants. Although wild type and transgenic plants showed no significant differences in agronomic traits under normal conditions, the overexpression of GmMYB68 increased grain number and 100-grain weights under salt stress. Our study identified a valuable TF associated with stress response in soybean, as its overexpression might help improve salt and alkali tolerance in soybean and other crops. Key words: Glycine max, GmMYB68, MYB family, salt tolerance. La salinite des sols contribue a diminuer significativement la production du soya (Glycine max L.) a l'echelle mondiale. La resistance aux stress chez les plantes est un caractere complexe regule par de nombreuses voies de signalisation. Le facteur de transcription homologue a l'oncogene du virus de la myeloblastose aviaire (v-Myb) joue des roles importants dans le developpement de la plante, dans le metabolisme secondaire et les reponses aux stress abiotiques. Des lignees sur-exprimant ou sous-exprimant (via l'ARNi) le gene GmMYB68 ont ete produites afin d'etudier la fonction de ce gene chez le G. max en reponse aux stress abiotiques. La sequence peptidique predite de GmMYB68 etait semblable a celles des proteines R2R3-MYB. Des analyses PCR en temps reel ont revele que l'expression du gene GmMYB68 variait en reponse aux stress abiotiques. Les lignees sur-exprimant ce gene ont montre une resistance accrue a la salinite et a l'alcalinite et que leur ajustement osmotique ainsi que leur activite photosynthetique etaient plus eleves que chez les lignees GmMYB68-ARNi ou sauvages. Bien que les plantes de type sauvage et les plantes transgeniques ne presentaient aucune difference au plan agronomique en conditions normales, la surexpression de GmMYB68 a augmente le nombre de grains et le poids de 100 grains en conditions de stress salin. Cette etude a permis d'identifier un facteur de transcription important associe a la reponse aux stress chez le soya, et a montre que sa surexpression pourrait contribuer a ameliorer la tolerance a la salinite et a l'alcalinite chez le soya et d'autres cultures. [Traduit par la Redaction] Mots-cles : Glycine max, GmMYB68, famille MYB, tolerance a la salinite., Introduction Soil salinity is a major detrimental factor for crop productivity (Munns and Gilliham 2015). Previous research has demonstrated that salt and alkaline salt stresses are two distinct types of [...]

Monitoring the gas composition in library environments is crucial for the preservation of ancient books. In this study, TiO2 NTs/CNTs composites were synthesized via a hydrothermal method and utilized as nano-gas sensors for NO2 detection. The surface morphology and element composition of the samples were characterized using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Additionally, the gas sensitivity of the prepared TiO2 nanocomposites was evaluated at different temperatures, both with and without ultraviolet light irradiation. The results demonstrate that the synthesized TiO2 NTs/CNTs samples exhibit a large specific surface area due to their titanium dioxide nanotubes (TiO2 NTs) and carbon nanotubes (CNTs) composition. Moreover, these samples display excellent gas sensitivity under ultraviolet light irradiation at temperatures of 120 °C. Compared to uncomposited and non-ultraviolet light irradiated samples, the sensor response rate is significantly improved, enabling effective monitoring of NO2 gas in library environments conducive to preserving ancient books. Overall, our findings highlight that the developed TiO2 NTs/CNTs nano gas sensor holds great potential for monitoring and safeguarding ancient books. [ABSTRACT FROM AUTHOR]

Photocatalytic carbon dioxide (CO2) to carbon monoxide (CO) offers a promising way for both alleviating the greenhouse effect and meeting the industrial demand. Herein, we constructed a Co single-atom catalyst with intentional low-coordination environment design on porous ZnO (denoted as Co1/ZnO). Impressively, Co1/ZnO exhibited a remarkable activity with a CO yield rate of 22.25 mmol·g−1·h−1 and a selectivity of 80.2% for CO2 photoreduction reactions under visible light. The incorporation of single Co atoms provided an additional photo-generated electron transfer channel, which suppressed the carrier recombination of photocatalysts. Moreover, the unsaturated Co active sites were capable to adsorb CO2 molecule spontaneously, thus facilitating the activation of CO2 molecule during CO2 reduction course. [ABSTRACT FROM AUTHOR]

Long-term operation of high voltage direct current at elevated temperatures can result in the accumulation of surface charges in DC gas-insulated transmission line (GIL) insulators. Such a phenomenon leads to localized electric field distortion, increasing the risk of surface discharge. The analysis of interaction behaviors between surface charge and space charge at interfacial domains of GIL insulators is a complex task, which requires a comprehensive understanding of physical mechanisms of the gas–solid interface charging. In this work, a two-dimensional bipolar charge transport and interaction (2D BCTI) model is established, with the consideration of both surface and space charge dynamics. Pulsed electroacoustic tests and surface potential measurements are conducted on DC GIL insulator materials under different electrical-thermal coupling conditions. Experimental results exhibit great consistency with the predictions from the 2D BCTI model. The local accumulation of space charge near interfaces has certain effects on surface potential distribution, which in turn influences charge injection behavior from electrodes. In comparison to traditional surface charge simulation models, the consideration of space charge–surface charge interaction behaviors proves to be essential for estimating the polarity and amplitude of surface potential distribution. This model holds promise for assessing charge characteristics in electrical equipment where direct measurement is challenging. [ABSTRACT FROM AUTHOR]

Background: Depression is a major health condition among the aging population. Previous studies indicated that edentulism was a risk factor for depression. The link between edentulism and depression has not been fully clarified. Objectives: This study aimed to estimate whether chewing difficulties play a mediating role in the association between edentulism and depression among middle‐aged and older populations with national cross‐sectional data. Methods: Data were obtained from the latest fourth wave of the China Health and Retirement Longitudinal Study (CHARLS). The outcome variable was set as depression, which was measured by the Center for Epidemiologic Studies Depression Scale (CES‐D‐10). Independent and mediated variables were separately set as self‐assessed edentulism and chewing difficulties. The nearest neighbour propensity score matching (PSM) method was used to construct a matching group to balance the basic characteristics of individuals with and without edentulism with minimised bias in the estimation. Causal mediation analysis was performed to estimate the degree of contribution of chewing difficulties to the association between edentulism and depression. Several sensitivity analyses were performed to evaluate the robustness of the primary result. Results: A total of 15 853 individuals remained for analysis. After PSM, 809 individuals with edentulism and 2628 without edentulism remained for analysis. Among the matched individuals, the mean age was 66.3 ± 9.2 years, 58.5% were female, 78.8% lived in rural areas, 23.5% had edentulism, 51.1% had depressive symptoms, and 50.1% had chewing difficulties. Logistic regression results showed that a higher incidence of edentulism was associated with a higher rate of depression (OR: 1.39, 95% CI: 1.19–1.63) in the matching group. Causal mediation analysis results indicated that the average mediation effect of chewing difficulties on the association between edentulism and depression was 0.010 (95% CI: 0.005–0.015), and the average direct effect was 0.072 (95% CI: 0.036–0.11). The mediation proportion of chewing difficulties was 11.7% (95% CI: 0.079–0.21). Conclusion: A higher prevalence of edentulism was associated with a higher rate of depression among middle‐aged and elderly populations. Chewing difficulties moderately mediated the association between edentulism and depression. Fundamental oral function should not be neglected to improve mental health among the aging population. [ABSTRACT FROM AUTHOR]

Biomass as a green renewable energy source has the potential to become a significant energy source in the future due to the depletion of fossil fuels. Herein, carbon dioxide was employed to enhance the acidic pretreatment of corn cobs with lithium bromide trihydrate (LBTH) system to extract low molecular weight lignin with high antioxidant activity. The main factors that have an influence on the degradation of carbohydrates and lignin in corn cobs were examined, such as the amount of CO2 and the reaction temperature during the treatment with the CO2/LBTH system. The results showed that the extraction yield rate of low molecular weight lignin and the total conversion of corn cobs were 81.6% and 83.5%, respectively, under the operating conditions of 76.2 g CO2 concentration at 100 °C for 4 h during the treatment of CO2/LBTH system. Specifically, the CO2/LBTH system promoted the breakdown of the β-O-4 aryl ether bond of lignin, resulting in the production of low molecular weight lignin with improved hydroxyl content and antioxidant activity. To transform inexpensive biomass resources into lignin with a high value-added, the CO2/LBTH system is thus of strategic and practical relevance. [ABSTRACT FROM AUTHOR]