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ObjectiveTo give a solid foundation for the epidemiological data of diarrheagenic Escherichia coli （DEC）， and provide a basis for the rational drug use for foodborne diseases caused by DEC， the continuous monitoring of DEC from 2018 to 2020 in Liaoning Province was carried out. The pathogenic characteristics and drug sensitivity characteristics of DEC were investigated.MethodsA total of 208 infant food in Liaoning Province were collected， from which Enterobacteriaceae was isolated， and 16S rRNA gene sequencing analysis and biochemical identification were carried out. The virulence genes of E.coli were detected. The serotype and drug resistance spectrum of EAEC were identified.ResultsIdentified species of Enterobacteriaceae by 16S rRNA gene sequencing method was consistent with the biochemical results. The detection rate of EAEC in infant food was high， and the detection rate of virulence gene pic of EAEC was high. Virulence genotyping was consistent with the serum typing. According to the virulence gene carried by Escherichia coli， 25 strains of EAEC were detected， of which 40% of the strains （serotype O134：H9） carried virulence gene pic， 28% of the strains （serotype O3：H2） carried virulence gene aggR and astA， 16% of the strains （serotype O9：H6） carried virulence gene aggR， and 16% of the strains （serotype O62：H7） carried virulence gene astA. The carrying rate of EAEC virulence gene in 78 strains was 32.1%. The drug resistance of 25 EAEC strains was not optimistic， and there were multiple drug-resistant strains. The resistance was mainly for β lactams， macrolides， quinolones and tetracyclines.ConclusionEAEC was the main contamination of Escherichia coli in infant food in Liaoning Province， and had high drug resistance， which need more attention to be paid to.

Fiber-reinforced composites offer the benefits of high strength, high stiffness, lightweight, superior damping performance, and great design capability when compared to metal. The rigidity characteristics of the composite laminate in different directions may be adjusted to meet the requirements of the application by using appropriate materials and arranging the lay-up sequence. As a result, the purpose of this work is to explore the influence of lay-up type on propeller performance in terms of both hydrodynamic and structural performance. A transient fluid-structure interaction (FSI) algorithm based on the finite element method (FEM) combined with the computational fluid dynamics (CFD) technique is developed and used for the analysis of composite propellers. The hydrodynamic performance of the propeller is compared to that of a metallic material. Propeller propulsion efficiency, structural deformation, equivalent stress, and damage performance of different lay-up options under three different operating situations are compared. In addition, it is presented a parametric optimization approach to get the most appropriate lay-up program for composite blades with the best hydrodynamic properties and structural performance.

The space-air-ground integrated networks (SAGINs) are pivotal for modern communication and surveillance, with a growing number of connected devices. The proliferation of IoT devices within these networks introduces new risks due to potential erroneous synergistic interactions that could compromise system integrity and security. This paper addresses the challenges in coordination, synchronization, and security within SAGINs by introducing a novel static program analysis (SPA) technique using zero-knowledge (ZK) proofs. This approach ensures the detection of risky interactions without compromising sensitive source code, thus safeguarding intellectual property and privacy. The proposed method overcomes the incompatibility between SPA and ZK systems by developing an imperative programming language for SAGINs and a specialized abstract domain for interaction threats. The system translates network control algorithms into arithmetic circuits suitable for ZK analysis, maintaining high accuracy in detecting risks. Evaluations of real-world scenarios demonstrate the system’s efficacy in identifying risky interactions with minimal computational overhead. This research presents the first ZK-based SPA scheme for SAGINs, enhancing security and confidentiality in network analysis while adhering to privacy regulations.