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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.

Existing optimized random phase (ORAP) approach mainly faces the limitations of fixed supports. Different ORAPs need to be generated for different target images with different support sizes, thus lacking flexibility and severely limiting applicability. This paper proposes a support-free optimized Fourier random phase (SF-OFRAP) approach for non-iterative kinoform generation, which greatly improves the speed and flexibility of generating kinoforms, and can achieve comparable performance to the ORAP approach. The proposed SF-OFRAP approach not only breaks the fixed support constraint of a target image, but can generate kinoforms of target images with different shapes, different positions, etc. with arbitrary supports. Our proposed SF-OFRAP approach can achieve real-time generation of kinoforms for multi-view holographic display using only a single generated SF-OFRAP without the need for additional phase compensation. The SF-OFRAP approach is suitable for real-time holographic display. Experiments verified the superiority of the produced SF-OFRAP over the ORAP method in terms of flexibility and adaptability to multiple different objects in different positions and different shapes using only one kind of these. The experimental results verify the effectiveness and excellent flexibility of SF-OFRAP for video holographic display and multi-view holographic display. [ABSTRACT FROM AUTHOR]

Diamide insecticides are widely used in rice paddies and pose a potential threat to aquatic organisms. However, the risk research related to their application in major rice‐producing areas is very limited, especially mesocosm research to simulate the impact on aquatic ecosystems of long‐term exposure, as well as exposure analysis based on local models and local scenarios. To assess potential risks from a novel diamide insecticide (tetrachlorantraniliprole) to aquatic nontarget organisms in the field over long‐term exposure, an outdoor mesocosm study was performed, and the environmental concentrations were predicted by the multimedia paddy‐pond model (TOPRICE). The mesocosm experiment showed that tetrachlorantraniliprole mainly stayed in the aqueous phase after entering the water body. Although the chemical dissipated quickly in the aqueous phase (half‐life of 0.79–1.5 days), it showed toxic effects on zooplankton communities. Cladocerans, represented by Simocephalus vetulus, were most sensitive to tetrachlorantraniliprole stress. Significant short‐term toxicity to cladocerans occurred in all treatment groups, but all recovered within 8 weeks except for the highest concentration group (30.0 µg /L). Based on the ecological recovery results, 7.74 µg tetrachlorantraniliprole/L (nominal concentration, 10.0 µg /L) is suggested to be the no‐observed‐ecological‐adverse‐effect concentration (NOEAEC) for the zooplankton community. When this NOEAEC was compared with predicted environmental concentrations (PECs; the PECs in natural ponds simulated by the TOPRICE model for 148 application scheme combinations in major rice‐producing areas), a relatively high risk of applying tetrachlorantraniliprole during the rice tillering stage was found. The present study makes a positive contribution to the hypothesis that the current Tier 1 approaches for global acute risk assessment have a sufficient protective effect for assessing the risk of tetrachlorantraniliprole to aquatic organisms. Also, the present results should help us to gain a fuller understanding of the ecological risk of diamide insecticides in aquatic ecosystems and their rational application schemes. Environ Toxicol Chem 2024;43:429–439. © 2023 SETAC [ABSTRACT FROM AUTHOR]

In this paper, we mainly study the weak convergence and convergence rates in the weak law of large numbers for weighted sums of negatively associated random variables. The necessary and sufficient conditions for the convergence rates in the weak law of large numbers are provided. As an application, the weak consistency for the weighted linear estimator of nonparametric regression models is established. Some numerical simulations are also provided to verify the validity of the theoretical result. [ABSTRACT FROM AUTHOR]

Objective: To observe the effect of dexmedetomidine (DEX) on the expression of tight junction protein ZO-1 in kidney tissues of rats with acute kidney injury (AKI) induced by sepsis., Methods: Sixty healthy male Sprague-Dawley rats were selected and divided into four groups: sham operation group (Sham group), DEX + Sham group, cecal ligation and puncture (CLP) group and DEX + CLP group according to a random number table, with 15 rats in each group. Each group was then divided into 3 subgroups at 6, 12, and 24 hours after the operation, with 5 rats in each subgroup. Modified CLP was used to establish a sepsis model. In Sham group and DEX + Sham group, only laparotomy and abdominal closure were performed. Each group was given pretreatment 1 hour before modeling. DEX + Sham group and DEX + CLP group were pumped into DEX at a rate of 5 μg×kg -1 ×h -1 through the caudal vein; Sham group and CLP group were pumped with the equal amount of normal saline through the caudal vein. Rats in each group were sacrificed at 6, 12, and 24 hours after operation to obtain kidney tissue. After hematoxylin-eosin (HE) staining, the pathological changes were observed under a light microscope, and the pathological score of renal injury was calculated. The positive expression level of ZO-1 in kidney tissue was detected by immunohistochemistry., Results: The pathological changes of rat kidney tissue could be seen at 6 hours after CLP. With the prolongation of postoperative time, the degree of renal injury showed a tendency to aggravate, with 24 hours being more significant. Semi-quantitative analysis showed that compared with the Sham group, the CLP group had significantly higher renal injury pathology scores at each time point (1.98±0.37 vs. 0.36±0.25 at 6 hours, 2.62±0.34 vs. 0.39±0.18 at 12 hours, 3.52±0.34 vs. 0.42±0.20 at 24 hours,all P < 0.01); the positive expression level of ZO-1 in kidney tissue was significantly reduced [percentage of positive area: (3.17±0.74)% vs. (10.83±0.83)% at 6 hours, (2.56±0.76)% vs. (9.02±0.88)% at 12 hours, (1.75±0.66)% vs. (8.25±0.94)% at 24 hours, all P < 0.01]. Compared with the CLP group, the pathological score of renal injury in the DEX + CLP group was significantly reduced at each time point (0.66±0.27 vs. 1.98±0.37 at 6 hours, 1.34±0.26 vs. 2.62±0.34 at 12 hours, 2.08±0.38 vs. 3.52±0.34 at 24 hours, all P < 0.01); the positive expression level of ZO-1 in kidney tissue was significantly increased [percentage of positive area: (8.58±0.86)% vs. (3.17±0.74)% at 6 hours, (7.44±1.05)% vs. (2.56±0.76)% at 12 hours, (6.60±0.87)% vs. (1.75±0.66)% at 24 hours, all P < 0.01]. There was no significant difference in renal injury pathology score and ZO-1 positive expression between the DEX+Sham group and the Sham group., Conclusions: DEX may reduce sepsis-induced AKI in rats by up-regulating the expression of tight junction protein ZO-1 in kidney tissue.

Objective: To evaluate the adsorption capacity of magnetic beads for common foodborne pathogens., Methods: Escherichia coli, Staphylococcus aureus, Listeria monocytogenes and Cronobacter sakazakii were used as targets, the suitable conditions were obtained by optimization the incubation time, bead size, reaction temperature and so on. The adsorption efficiency of the magnetic beads in analog samples was also tested., Results: The optimum conditions were as follows: 2.0 - 3.0 microm diameter magnetic beads 50 microl, incubation for 60 min under 37 degrees C. In analog samples, the adsorption efficiency of the magnetic beads for Escherichia coli, Staphylococcus aureus, Listeria monocytogenes and Cronobacter sakazakii in juice, milk, duck meat were 50% - 84%, 46% - 66%, 54% - 74%, respectively., Conclusion: Magnetic beads enrichment technique has high adsorption efficiency, simple to operate, which is meet the requirement for PCR detection.

Objective: To establish a real-time PCR assay for the rapid detection of Listeria monocytogenes in simulated milk specimens., Methods: Based on part fragments of hlyO gene, a pair of primers and Taq-Man probe were designed for quantitative detection of L. monocytogenes. The specificity of the primers and probe were tested by using different L. monocytogenes strains and other common pathogenic bacteria., Results: L. monocytogenes strains were positive in the detection and other tested strains were negative. The sensitivity of assay was 9 copies per PCR reaction., Conclusion: The specificity and sensitivity of Taq Man real-time PCR technology for detecting L. monocytogenes in simulated dairy specimens were high, and the assay could be completed within 1.5 h. This method could be used to detect other food samples contaminated by L. monocytogenes and identify the cause of food-borne Listeriosis outbreaks.

Enterobacter sakazakii, one of the major pathogens affecting the safety of infant formula powder was defined as a species in 1980. However, the new names and new combinations about Enterobacter sakazakii notified in volume 58, part 6, of the International Journal of Systematic and Evolutionary Microbiology (IJSB). The taxonomic relationship of strains described as E. sakazakii, biological characteristics of its new genus and species, the development related to its isolation and identification were reviewed in this paper, in order to facilitate the related personnel to keep in touch with the latest developments on E. sakazakii. It's also conducive to unify and standardize the Chinese name for E. sakazakii.