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Polar materials, with intrinsic polarization effects, present significant potential for photo(electro)catalysis. However, the available natural polar materials in this field are quite scarce, due to the requisite structural non‐centrosymmetry. Defect engineering emerges as a promising avenue for tuning material symmetry, yet achieving the transition from centrosymmetric to non‐centrosymmetric structures and optimizing associated polarization effects remains challenging. This study demonstrates symmetry breaking in centrosymmetric 3R‐delafossite AgFeO2 through ordered oxygen defects introduction, yielding substantial macroscopic polarization. The transition is achieved via annealing post‐treatment of co‐precipitation‐hydrothermal AgFeO2 samples, with precision in oxygen defects control by tailoring annealing conditions. Experimental characterizations reveal ordered interstitial oxygen and disordered oxygen vacancies. Density functional theory calculations indicate a higher propensity for the formation of disordered oxygen vacancies compared to ordered ones, while ordered interstitial oxygen is more easily formed than its disordered counterpart. Resultant macroscopic polarization enhances photoelectrochemical performance, with photocurrent density increasing from 0.79 to 2.95 µA cm−2. Coupling macroscopic and spin polarization via external electric and magnetic fields further enhances photocurrent density (≈18.44 µA cm−2). These findings provide reference cases and strategies for applying polarization effects in photo(electro)catalytic technology. [ABSTRACT FROM AUTHOR]

Sunlight splitting water to produce hydrogen has become a feasible solution to the energy crisis and environmental problems. As one of the most popular photocatalysts, TiO2 still has many advantages that attract many researchers. Single-atom loaded TiO2 has garnered significant attention and usage as a water splitting photocatalyst, but still there is an urgent requirement to discover a stable, efficient, and cost-effective approach to achieve stable single-atom catalysts. In this investigation, a one-step microwave hydrothermal method was employed to fabricate Pd single-atom loaded TiO2. The prepared samples exhibit particle sizes in the range of 6–7 nm, showcasing excellent dispersion and a substantial specific surface area. The Pd atoms are securely anchored, forming stable Pd–O bonds with the support material. The resulting Pd–TiO2 catalyst exhibited an impressive hydrogen evolution rate of 24.6 mmol g–1 h–1, accompanied by an AQY of 23.4% at 365 nm. This research presents a viable and economical strategy for producing single-atom loaded catalysts with high efficiency. [ABSTRACT FROM AUTHOR]

Objective To investigate the drug resistance of Enterobacter cloacae isolated from blood samples in 75 member units of the Bacterial Drug Resistance Monitoring Network in Hebei, 2016- 2021, so as to provide a basis for rational drug use in clinic. Methods WHONET 5.6 software was used to retrospectively analyze drug susceptibility of Enterobacter cloacae isolated from 32 secondary hospitals and 43 tertiary hospitals. SPSS19.0 software was used for statistical analysis. Results After removing the duplicate strains, 1 225 strains of E. cloacae were isolated from blood samples of 75 hospitals during 6 years, including 157 strains from secondary hospitals and 1 068 strains from tertiary hospitals. In this study, the resistance of Enterobacter cloacae to 16 kinds of antibiotics was analyzed. The drug resistance rates to cefuroxime (52.4%- 67.8%), piperacillin (27.4%-31.2%), ceftazidime (27.8%-35.5%), ceftriaxone (29.5%-45.0%), aztreonam (22.2%-32.3%), cotrimoxazole (21.6% - 28.7%) were higher; the resistance rates to amikacin and tobramycin were lower than 15.0%. The resistance rates to imipenem and meropenem were 3.6% - 12.3% and 5.1% - 11.4%, respectively. The resistance rate to ciprofloxacin in tertiary hospitals was 22.4%, and the resistance rate to cotrimoxazole was 23.9%. Except for these two antimicrobials, the resistance rates to other antimicrobial drugs in tertiary hospitals were higher than that in secondary hospitals. A total of 121 carbapenem-resistant Enterobacter cloacae strains were detected in the past 6 years, with an increasing detection rate (χ² trend=6.305, P=0.012). Conclusions Enterobacter cloacae has great differences in antimicrobial resistance to different antibiotics, and is sensitive to carbapenems. The drug resistance in tertiary hospitals is generally higher than that in secondary hospitals. Drug resistance monitoring and drug resistance mechanism research should be strengthened to better guide clinical drug use and curb the rise of drug resistance. [ABSTRACT FROM AUTHOR]

In Mycobacterium tuberculosis, the proX gene encodes a putative compatible solute‐binding protein (MtProX). However, it was found through sequence alignment that the MtProX protein has very different ligand‐binding residues compared with other compatible solute‐binding proteins, implying that MtProX may bind to ligands that are as yet uncharacterized. In this work, it was demonstrated that MtProX binds to polyphenols such as phloretin, monoacetylphloroglucinol and 2,4‐dihydroxyacetophloroglucinol with dissociation constants between 20 and 70 µM. Crystals of MtProX were obtained using a precipitant consisting of 0.2 M NaCl, 0.1 M Tris pH 8.5, 25%(w/v) polyethylene glycol 3350. The crystals diffracted to 2.10 Å resolution and belonged to space group P43212, with unit‐cell parameters a = b = 90.17, c = 161.92 Å, α = β = γ = 90.0°. Assuming the presence of two MtProX molecules in the asymmetric unit, the Matthews coefficient was calculated to be 2.74 Å3 Da−1, which corresponds to a solvent content of 55%. [ABSTRACT FROM AUTHOR]