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Burkholderia semiarida has only been reported as a plant pathogen causing onion sour skin (1). The Burkholderia genus encompasses >120 bacterial species that are typically reported to inhabit soil and [...]

In situ construction of metal halide perovskite (MHP)-based heterojunctions via atom cosharing has been regarded as an effective strategy to enhance photocatalytic activity, as it establishes high-quality interfaces for rapid charge transfer and separation. Here, the potential of a functional bimetallic self-template for manipulating the composition, structure and consequently the photoelectric properties of atom-cosharing MHP-based heterojunctions was investigated. We employed Sillén-structured bimetallic oxyhalide PbBiO2Br nanosheets as the self-template to in situ epitaxially grow Pb- and Bi-based or mixed MHP nanocrystals via an acid-etching process. It was revealed that the two "B site" metals, Pb2+ and Bi3+, enabled the in situ growth of Bi-doped CsPbBr3 (Bi-CsPbBr3), CsPb2Br5, or Cs3Bi2Br9 nanocrystals on the surface of PbBiO2Br nanosheets, which could be facilely controlled by tuning the HBr dosage. Therefore, both light absorption and interfacial charge separation of the heterojunction could be facilely tuned simultaneously, which contributed to the manipulation of the corresponding photocatalytic performance. The optimized PbBiO2Br/Bi-CsPbBr3 heterojunction exhibited a total electron consumption rate of 31.38 μmol g−1 h−1 when used as the photocatalyst for CO2 reduction, which was 13.76 times higher than that of the single PbBiO2Br. Further surface modification by ZIF-67 enhanced the charge separation and CO2 uptake of the heterojunction, leading to an improved total electron consumption rate of 45.72 μmol g−1 h−1 and enhanced photocatalytic stability. This work provides a simple and effective method for the in situ synthesis of high-quality perovskite heterojunctions, which could be easily extended to other atom-cosharing heterojunctions. [ABSTRACT FROM AUTHOR]

S. Typhimurium is a significant zoonotic pathogen, and its survival and transmission rely on stress resistance and virulence factors. Therefore, identifying key regulatory elements is crucial for preventing and controlling S. Typhimurium. We performed transcriptomic analysis and screened for a c-di-GMP pathway key gene STM0343, a putative EAL domain protein with an unknown function. Our findings revealed that the deletion of this gene (269ΔSTM0343) led to a 29.85% increase in c-di-GMP. In terms of stress resistance, the strain 269ΔSTM0343 showed significant improvements compared to the wild strain WT269. Specifically, it exhibited increases of 95.74% in extracellular protein and 35.96% in exopolysaccharide production by upregulating the expression of relevant genes. As a result, the biofilm formation ability of 269ΔSTM0343 was enhanced by 21.54%, accompanied by a more pronounced red, dry, and rough colony morphology. 269ΔSTM0343 also showed a 19.03% decrease in motility due to the downregulation of flhD expression. As a result, 269ΔSTM0343 increased resistance to various antibiotics, as well as to acidic conditions, oxidative stress, and disinfectants. In terms of virulence, compared to WT269, the adhesion and invasive ability of 269ΔSTM0343 to HeLa cells was enhanced by onefold and 25.67%, respectively. In in vivo experiments, mice challenged with 269ΔSTM0343 experienced greater weight loss, and the bacterial loads in the spleen, liver, and intestines were elevated by fivefold, 30-fold, and 21-fold, respectively, accompanied by more severe pathological damage. Mechanistic studies revealed that the adhesion and invasion capacities of 269ΔSTM0343ΔCsgB decreased by 29.41% and 68.58%, respectively, compared to 269ΔSTM0343. Additionally, LacZ gene reporting indicated that STM0343 inhibited the expression of CsgB. This suggests that STM0343 suppresses virulence by downregulating CsgB expression. This study provides insights into the regulatory mechanisms by which STM0343 reduces the stress resistance and pathogenicity of S. Typhimurium. [ABSTRACT FROM AUTHOR]

This study aimed to explore the interactions among genetic determinants influencing ciprofloxacin resistance in Salmonella. Treatment with PAβN, an efflux pump inhibitor, resulted in a 4–32-fold reduction in the minimum inhibitory concentration (MIC) across all 18 ciprofloxacin-resistant Salmonella isolates. Notably, isolates without point mutations reverted from resistance to sensitivity. The efflux pump played a crucial role in resistance development, particularly in serovar Enteritidis, where PAβN treatment caused a more significant MIC reduction (16–32-fold) in five strains carrying the GyrA (Asp87Tyr) mutation, which initially exhibited high MICs (8 μg/mL). Several resistance genes were identified on transferable plasmids: oqxAB and aac(6′)-Ib-cr were associated with IncF plasmids in S. Enteritidis, IncA/C plasmids in S. Typhimurium, and IncHI2 plasmids in S. Virchow. Additionally, qnrS1 and/or qepA were carried by IncA/C plasmids in S. Thompson. Whole-genome sequencing revealed the presence of an oqxAB module integrated into the chromosomal DNA of S. Derby. Although the MICs of ciprofloxacin in transconjugants and transformants remained low (1–4 μg/mL), they exceeded the clinical breakpoint for susceptibility. These findings highlight the synergistic impact of efflux pumps and plasmid-mediated resistance mechanisms, contributing to the increasing prevalence of ciprofloxacin resistance and posing a significant threat to food safety. [ABSTRACT FROM AUTHOR]

High-quality and large-size crystals are ideal scintillation screens to achieve high-resolution X-ray imaging. However, it is difficult to obtain large-size scintillation crystals due to the limitations of crystal growth technology. Here, organic–inorganic hybrid Mn-based single crystals (TBP2MnBr4, TBP = tetrabutylphosphonium) exhibit a high decomposition temperature (295 °C) and the TBP2MnBr4-melt has a low condensation point (48.75 °C), such a wide interval is of benefit to the melt processing method for preparing scintillation screens. The TBP2MnBr4-melt exhibits a low viscosity (η(Tm) = 238 mPa s) and flow activation energy (Ea = 10.754 kJ mol−1) making it easy to crystallize. It is worth noting that the low condensation point (Tc) of the TBP2MnBr4-melt is slightly higher than room temperature, and this narrow temperature interval can limit the rapid nucleation and growth of the crystals, allowing them to slowly crystallize into transparent ceramics (TC). Circular TBP2MnBr4-TC with a size of Φ 11.5 cm can be easily fabricated, which exhibits high optical transmittance, for realizing high-resolution (16 lp mm−1) X-ray imaging. This work brings a new strategy for preparing scintillation screens, as well as promoting the development of TC scintillators for X-ray imaging. [ABSTRACT FROM AUTHOR]

Organic scintillators are praised for their abundant element reserves, facile preparation procedures, and rich structures. However, the weak X‐ray attenuation ability and low exciton utilization efficiency result in unsatisfactory scintillation performance. Herein, a new family of highly efficient organic phosphonium halide salts with thermally activated delayed fluorescence (TADF) are designed by innovatively adopting quaternary phosphonium as the electron acceptor, while dimethylamine group and halide anions (I−) serve as the electron donor. The prepared butyl(2‐[2‐(dimethylamino)phenyl]phenyl)diphenylphosphonium iodide (C4‐I) exhibits bright blue emission and an ultra‐high photoluminescence quantum yield (PLQY) of 100 %. Efficient charge transfer is realized through the unique n‐π and anion‐π stacking in solid‐state C4‐I. Photophysical studies of C4‐I suggest that the incorporation of I accounts for high intersystem crossing rate (kISC) and reverse intersystem crossing rate (kRISC), suppressing the intrinsic prompt fluorescence and enabling near‐pure TADF emission at room temperature. Benefitting from the large Stokes shift, high PLQY, efficient exciton utilization, and remarkable X‐ray attenuation ability endowed by I, C4‐I delivers an outstanding light yield of 80721 photons/MeV and a low limit of detection (LoD) of 22.79 nGy ⋅ s−1. This work would provide a rational design concept and open up an appealing road for developing efficient organic scintillators with tunable emission, strong X‐ray attenuation ability, and excellent scintillator performance. [ABSTRACT FROM AUTHOR]

Stimuli‐responsive luminescent materials have attracted much research attention due to their wide application potential in various fields. Typically, the family of hydrated double perovskite A2MIIIX5·H2O shows unique emission color transformation between hydrated and dehydrated complexes, highlighting the application potential in advanced anti‐counterfeiting. Herein, two zero‐dimensional perovskites of Cs2YbCl5·H2O and Cs3YbCl6, are reported and broad‐band self‐trapped exciton recombination emission can be realized via external Sb3+ doping. Intriguingly, the Cs2YbCl5·H2O can be transformed to the dehydrated counterpart of Cs3YbCl6 through a facile methanol treatment at room temperature, leading to the emission color transformation from yellow to green. Notably, the green‐emissive Cs3YbCl6:Sb3+ delivers a high photoluminescence quantum yield of 67.3%. Leveraging the advantages of obvious methanol‐induced emission color transformation between Cs2YbCl5·H2O and Cs3YbCl6 at room temperature, Cs2YbCl5·H2O can be used in the field of high‐security‐level anti‐counterfeiting. [ABSTRACT FROM AUTHOR]

The development of large‐area transparent organic‐inorganic hybrid metal halide (OIMH) scintillation screens is restricted by the anisotropic single‐crystal growth, numerous grain boundaries in polycrystalline wafers, and inhomogeneous dispersion in perovskite‐polymer composite films. The crystal‐glass phase transition of OIMH materials may provide a promising solution for the above significant challenges. Herein, a new class of transparent amorphous guanidinium‐based manganese bromide glasses, (DPG)2MnBr4 and (DOTG)2MnBr4 (DPG = 1,3‐diphenylguanidinium, DOTG = 1,3‐di‐o‐tolylguanidinium), are synthesized through a low‐temperature melt‐quenching process. The (DOTG)2MnBr4 shows impressive glass‐forming ability because of large viscosity (η) at the melting temperature (Tm) (η(Tm) = 3426 mPa·s) and small fragility index (m = 52.35), which can be a potential glass scintillator. The large‐area (e.g., 13 cm × 13 cm) transparent amorphous (DOTG)2MnBr4 glass scintillator shows high light transmittance of > 80%, a low detection limit of 237.3 nGy s−1 and high X‐ray imaging spatial resolution of 12 lp mm−1. Interestingly, the glass transition temperature of < 40 °C gives (DOTG)2MnBr4 glass unique thermoplastic properties, allowing it to conform to irregularly shaped objects and reduce the distortion in X‐ray imaging. [ABSTRACT FROM AUTHOR]