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ObjectiveTo analyze the influencing factors of Salmonella contamination， the serotype distribution and molecular typing of Salmonella isolates in meat products in Yibin city were studied.MethodsA total of 29 Salmonella strains isolated from commercial meat products in Yibin city of from 2015 to 2020 were analyzed by slide agglutination test for serotype and pulsed field gel electrophoresis（PFGE） for molecular subtyping. Multivariate Logistic regression analysis was carried out on the effects of geographical distribution， sample source and sales mode on the detection composition of Salmonella serogroup.ResultsFourteen serotypes and 4 serogroups were detected in the Salmonella isolates. The dominant bacteria were Salmonella typhimurium， Salmonella give and Salmonella enteritidis. The PFGE cluster analysis showed 18 genotype. The genotypes of Salmonella enteritidis were highly homologous with similarity index of 100%， indicating the same source. Salmonella typhimurium with 4 genotypes and Salmonella give with 2 genotypes both had lower similarity. Multivariate Logistic analysis showed that the risk factor on serogroup D of Salmonella was geographical distribution （OR=1.053， P

Effective teaching is an important research topic worldwide. This review aims to analyze effective teaching literature in China with respect to general characteristics and conceptional dimensions. Two types of effective teaching literature, empirical studies written in Chinese and written in English, are selected for this review. Stronge's effective teaching framework is adopted for examining the conceptual dimensions in the selected studies. The results taken from the two types of literature reveal different research orientations regarding effective teaching. The literature written in Chinese demonstrates a number of quantitative research studies that, overall, are ill-written from the standard criteria of empirical study writing, including serious design flaws, missing important information, and weak data interpretations. In contrast, the literature written in English tends to focus more on a qualitative research orientation with sufficient overall quality for methodological design. Regarding the effective teaching dimensions, the dimension of the "Teacher as a Person" is interpreted differently, while the dimension of "Implementing Instruction" is most often commonly adopted in the two types of literature. We suggest that more studies are needed to conceptualize effective teaching frameworks from macro, meso, and micro levels in order to enhance the quality of effective teaching research in China. Additionally, effective teaching studies related to minority students are rare and deserve future investigation.

Poor cellular permeability greatly hampers the utilization of anionic Ir(III) complexes, though efficiently emissive and remarkably stable, in cell-based diagnosis. To overcome this barrier, we present the development of an alkaline phosphatase (ALP)-responsive, anionic, and aggregation-induced emission (AIE)-active Ir(III) complex (Ir1) for specific recognition of osteosarcoma cells. Containing phosphate moieties, Ir1 exhibits a net −1 charge, enabling charge repulsion from the cell membrane and resulting in low cellular uptake and good biocompatibility in normal osteoblast cells. Upon ALP-mediated hydrolysis of phosphate groups, the resulting dephosphorylated product, Ir2, demonstrates a positive charge and increased lipophilicity, promoting cellular uptake and activating its AIE properties for specific recognition of osteosarcoma cells that express elevated levels of ALP. This study elucidates the role of ALP as an ideal trigger for enhancing the cellular permeability of phosphate ester-containing Ir(III) complexes, thus expanding the potential of anionic Ir(III) complexes for biomedical applications. [ABSTRACT FROM AUTHOR]

Memristors based on 2D semiconductors hold great promise due to their atomic‐level thickness and tunable optoelectronic properties. However, a significant challenge lies in suppressing the large off‐state current, which leads to additional standby power consumption. Here, a simple and versatile method is presented to address this issue by introducing a thin h‐BN interlayer between 2D semiconductors and the electrodes. The thickness of the h‐BN interlayer serves as a pivotal parameter for modulating the interfacial Schottky barrier, thereby influencing the off‐state current level. This fabricated graphene/α‐In2Se3/h‐BN/Cr‐Au memristor, forming a van der Waals heterostructure, exhibits unipolar resistive switching behavior. Remarkably, the memristor incorporating an 8 nm h‐BN interlayer showcases an ultralow off‐state current of 4.2 × 10−13 A, five orders of magnitude lower than that without the h‐BN interlayer. It also achieves a current switching on/off ratio of up to 109 and realizes 32 distinct resistance states, enabling robust multi‐bit memory capabilities. Excellent stability and durability are maintained due to the self‐encapsulation of the h‐BN interlayer. Furthermore, this method is also applicable to memristors built on HfS2, WS2, and WSe2, highlighting its broad potential for technological applications. [ABSTRACT FROM AUTHOR]