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ObjectiveThis study aimed to understand the epidemic characteristics of Diarrheagenic Escherichia coli （DEC） in domestic meat products.MethodsThe molecular characteristics of 86 strains of DEC were analyzed by whole genome sequencing technology， and the dominant pathological types， STs， and serotypes were identified. The phylogenetic relationship between DEC strains derived from meat products in China was determined through whole genome single nucleotide polymorphism.ResultsThe results showed that the pathological types of DEC in meat products were mainly EAEC. Eighty-six DEC strains were divided into eight virulence genotypes， including 48 ST types （including six new ST types）， and 55 O：H serotypes. ST11 and CC10 were the predominant ST and clonal complex， respectively. O157， O15， and O6 were the predominant serogroups. DEC strains exhibited high genetic heterogeneity， the same pathological type had low homology， and they were in different evolutionary branches.ConclusionThere is no correspondence between DEC pathological types and ST types and serotypes. The pathological types cannot be directly judged by monitoring ST types and serotypes， but the most numerous ST types and serotypes reveal the main hazard characteristics and prevention of DEC. The determination method of DEC can be supplemented and optimized according to the results of whole genome sequencing， which can provide data support for the traceability and epidemiological investigation of DEC in the future.

Establishing a harmonious equilibrium between high energy storage, minimal energy loss, and exceptional processability presents a formidable challenge within the realm of dielectric polymers. To address this challenge, harnessing the characteristics of long‐chain side groups to enhance polarity and toughness, as well as the fluorine effect to improve insulation and efficiency, a random copolymer, poly(4‐fluorostyrene‐trifluoroethyl methacrylate) (P(FS‐3FEMA)), is successfully synthesized via copolymerization of fluorine‐containing monomers, namely 4‐fluorostyrene (FSt) and trifluoroethyl methacrylate (3FEMA). Experimental findings demonstrate that elongating side chains enhances polymer toughness, boosts polarization strength, and self‐healing capacity. Introducing fluorine atoms into side chains maintains toughness while marginally increasing polymer chain spacing, reducing relaxation loss induced by dipole reorientation under an applied electric field. Additionally, fluorine incorporation enhances electron capture, effectively reducing leakage loss and the likelihood of thermal and electrical breakdown. Ultimately, the copolymer exhibits exceptional performance, characterized by extraordinarily high energy storage (Ue = 18.3 J cm−3), minimal energy loss (efficiency exceeding 89%), and enhanced toughness (increased by over 112%). This study presents a novel approach that harnesses the fluorine effect to reconcile the conflicting requirements of high energy storage, minimal energy loss, and exceptional processability in polymer dielectrics. [ABSTRACT FROM AUTHOR]

As a famous probiotic, Lacticaseibacillus rhamnosus HN001 is widely added to probiotic products. Different L. rhamnosus strains have different probiotic effects, and the active HN001 strain is the key to exerting probiotic effects, so it is of great practical significance for realising the detection of L. rhamnosus HN001 at the strain level in probiotic products. In this study, strain-specific primer pairs and probes were designed. A combined treatment of sodium deoxycholate (SD) and propidium monoazide (PMA) inhibited the amplification of dead bacterial DNA, establishing a SD-PMA-ddPCR system and conditions for detecting live L. rhamnosus HN001 in probiotic powders. Specificity was confirmed using type strains and commercial strains. Sensitivity tests with spiked samples showed a detection limit of 10⁵ CFU/g and a linear quantification range of 1.42 × 10⁵–1.42 × 10⁹ CFU/g. Actual sample testing demonstrated the method's efficiency in quantifying HN001 in compound probiotic products. This method offers a reliable tool for the rapid and precise quantification of viable L. rhamnosus HN001, crucial for the quality monitoring of probiotic products. [ABSTRACT FROM AUTHOR]