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We herein report a visible light induced dehydrogenative phosphonylation reaction of glycine derivatives and di‐aryl phosphine oxides. A diverse range of phosphine‐glycine derivatives were constructed under ambient condition in the absence of catalyst and additives. A plausible mechanism was also proposed. [ABSTRACT FROM AUTHOR]

Practical aqueous zinc‐ion batteries require low‐cost thin zinc anodes with long‐term reversible stripping/depositing. However, thin zinc anodes encounter more severe issues than thick zinc, such as dendrites and uneven stripping, resulting in subpar performance and limited lifetimes. Here, this work proposes a three‐in‐one zinc anode obtained by a large‐scale two‐step method to address the above issues. In a three‐in‐one zinc anode, the copper foil as an inactive current collector solves the gradual reduction of the active area when only the pure zinc as an active current collector. This work develops an automatic electroplating device that can continuously deposit a zinc layer on a conducting foil to meet the demand for zinc‐coated copper foils. The sodium carboxymethylcellulose (CMC)‐zinc fluoride (ZnF2) protective layer prevents direct contact between zinc and separator, and provides a uniform and sufficient supply of zinc ions. The CMC‐ZnF2‐coated copper foil performs up to 3000 reversible zinc deposition/stripping cycles with a cumulative capacity of 6 Ah cm−2 and an average Coulombic efficiency of 99.94%. The Zn||ZnVO cell using the three‐in‐one anode achieved a high capacity retention of over 70% after 15 000 cycles. The proposed three‐in‐one anode and the automatic electroplating device will facilitate industrialization of practical thin zinc anodes. [ABSTRACT FROM AUTHOR]

The rice waterlogging stress test was conducted at the experimental base of the College of Agriculture, Yangtze University, using Yangxian You 418 as the test subject, in order to investigate the impact of waterlogging on rice growth during the period from July to August each year. Six waterlogging stress tests with different waterlogging depth (1/4 plant height (1/4PH), 2/4 PH, and 3/4 PH) and duration (5 d and 7 d) were set up at the jointing–booting stage of rice (T1: 1/4 PH, 7 d; T2: 2/4 PH, 7 d; T3: 3/4 PH, 7 d; T4: 1/4 PH, 5 d; T5: 2/4 PH, 5 d; T6: 3/4 PH, 5 d;) with shallow water irrigation (CK) as control. The plant height, population leaf area, above-ground dry matter, and the yield of rice were measured. The correlation between the waterlogging depth and rice yield reduction was analyzed, and the flood disaster threshold index of rice was established. The results showed that at the end of stress, the plant height of all waterlogged treatments exceeded CK, and the plant height of T3 and T6 treatments significantly increased by 31.90% and 15.93%, respectively. The leaf area of rice treated with T1, T3, T4, and T5 was higher than CK (p < 0.05), and the above-ground dry matter of rice treated with T2, T3, T4, T5, and T6 was higher than CK (p < 0.05). When normal irrigation was restored to the maturity stage, the plant height of all rice treated with waterlogging was still higher than CK (p < 0.05). However, as the degree of waterlogging increased, rice yield decreased significantly, with a notable reduction of 31.68% observed in the T3 treatment compared to CK. Assuming a drainage index based on a 20% decrease in rice yield, it is imperative that the ratio of flooded depth to plant height remains below 37% when waterlogging persists for 7 days in rice cultivation. These research findings offer crucial scientific insights for implementing effective drainage management measures during flood disasters in rice paddies. [ABSTRACT FROM AUTHOR]

To analyze the antibiotic resistance profile, virulence genes, and molecular typing of Staphylococcus aureus (S. aureus) strains isolated in skin and soft tissue infections at the First Affiliated Hospital, Gannan Medical University, to better understand the molecular epidemiological characteristics of S. aureus. Methods: In 2023, 65 S. aureus strains were isolated from patients with skin and soft tissue infections. Strain identification and susceptibility tests were performed using VITEK 2 and gram-positive bacteria identification cards. DNA was extracted using a DNA extraction kit, and all genes were amplified using polymerase chain reaction. Multilocus sequence typing (MLST) was used for molecular typing. Results: In this study, of the 65 S. aureus strains were tested for their susceptibility to 16 antibiotics, the highest resistance rate to penicillin G was 95.4%. None of the staphylococcal isolates showed resistance to ceftaroline, daptomycin, linezolid, tigecycline, teicoplanin, or vancomycin. fnbA was the most prevalent virulence gene (100%) in S. aureus strains isolated in skin and soft tissue infections, followed by arcA (98.5%). Statistical analyses showed that the resistance rates of methicillin-resistant S. aureus isolates to various antibiotics were significantly higher than those of methicillin-susceptible S. aureus isolates. Fifty sequence types (STs), including 44 new ones, were identified by MLST. Conclusion: In this study, the high resistance rate to penicillin G and the high carrying rate of virulence gene fnbA and arcA of S.aureus were determine, and 44 new STs were identified, which may be associated with the geographical location of southern Jiangxi and local trends in antibiotic use. The study of the clonal lineage and evolutionary relationships of S. aureus in these regions may help in understanding the molecular epidemiology and provide the experimental basis for pathogenic bacteria prevention and treatment. [ABSTRACT FROM AUTHOR]

An electrochemical method for the decarboxylative alkylation of β-ketoacids with phenol derivatives has been developed. The protocol was carried out in readily available unseparated cells at room temperature in the absence of catalysts and oxidants. The corresponding aryl ketones were obtained in satisfactory yields without additional electrolytes, and were easy to produce in gram-scale synthesis. Based on control experiments and cyclic voltammetry, a plausible reaction mechanism was proposed. [ABSTRACT FROM AUTHOR]

Hairpin DNA containing split G-quadruplex at its terminus displayed tagging position-dependent horseradish peroxidase activity. In general, the hairpin DNA coupled with one GGG repeat at its 5'-terminus and three GGG repeats at its 3′-terminus demonstrated strong catalytic activity, while slight activity was observed after exchanging the position of split G-quadruplex sequence. Inspired by these observations, a novel colorimetric biosensor for nuclease activity assay was developed by selecting S1 nuclease as the model. Specifically, S1 nuclease cleaves the split G-quadruplex into mono- or oligonucleotide fragments, thereby suppressing the catalytic activity, accompanied by a color change from blue to colorless. Under optimum conditions, S1 nuclease was determined with a linear range from 1.60 to 17.6 U/mL and a detection limit of 1.458 U/mL. The constructed method was simple and did not require complex sequence design, expensive instrumentation, and probe labeling. Most importantly, this work facilitates a better understanding of the catalytic mechanism of the DNAzyme and provides an example of the practical application of G-quadruplex-based DNAzyme. [ABSTRACT FROM AUTHOR]

Objective: To explore the molecular mechanism of oxymatrine (OM) by increasing the phosphorylation of ERK1/2 signal factor and blocking the transcription factors HNF1α and HNF4α expression against hepatitis B virus (HBV) antigen secretion and HBV DNA replication in HepG2.2.15 cells., Study Design: An experimental study. Place and Duration of the Study: Department of Laboratory Medicine, First Affiliated Hospital of Gannan Medical University, Jiangxi, China, between May 2020 and December 2022., Methodology: HepG2.2.15 cells, known for stably expressing HBV particles, were utilised as a cell-based model to explore potential pathways pertaining to the OM inhibition of HBV replication. An MTT assay was utilised to measure cytotoxicity. HBsAg or HBeAg content was measured using an enzyme-linked immunosorbent assay kit. HBV DNA in cell-free culture media was examined using a fluorescent quantitative PCR kit. Real-time PCR was utilised to analyse HNF1α and HNF4α mRNA expression, whereas Western blotting was performed to evaluate HNF1α, HNF4α, and ERK1/2 protein expression., Results: OM inhibited HBV DNA copy number in the cell supernatant, 3.5-kb RNA gene expression in cells, and HBsAg and HBeAg secretion. OM upregulated p-ERK1/2 protein and significantly downregulated HNF1α and HNF4α gene transcription and protein translation., Conclusion: OM may inhibit the replication of HBV by inducing the phosphorylation of ERK1/2 and blocking the transcription factors HNF1α and HNF4α expression that are essential for viral replication., Key Words: Oxymatrine, ERK1/2, Hepatocyte nuclear factor, Anti-HBV.