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Students' informal science learning experiences are believed to strongly influence their attitudes toward science and their abilities in the subject. Factors associated with students' informal science learning experiences include family socioeconomic status and perceived family support. However, little is known about whether perceived family support for children's formal and informal science learning differs significantly. The present study filled this gap by exploring how students' perceived family support for formal/ informal science learning affected the link between their socioeconomic status and their experiences of informal science learning. Survey data were collected from 486 Chinese grade 4-6 primary school students. Structural equation modeling demonstrated that the students' socioeconomic status and their informal science learning experiences were significantly and positively correlated. This association was chain-mediated through two categories of perceived family support. Specifically, students' socioeconomic status affected their informal science learning experiences through the separate mediating role of family support for formal science learning and the sequential mediation of perceived family support for formal and informal science learning. These results uncover the role that family support plays in students' science education; accordingly, parents are encouraged to help their children learn science both formally and informally.

Objective: To realize the full automation of shrimp deep processing. Methods: Based on analysis of physical characteristics of northern and southern American shrimps, according to the feature of the center of gravity located between the thickest part of the shrimp body and the tail of the shrimp, an automatic orientation and grading device of shrimp head and tail was designed. Taking the clip angle between directional roller shaft line and horizontal line and the speed of directional roller as testing factors, the directional components were tested. Results: When the directional roller speed was 60 r/min, and the angle between axis line and horizontal line was 15°, the falling speed of shrimp was even and stable with high directional rate, which was benefit for subsequent grading transportation. Conclusion: The device realizes the shrimp head and tail positioning and classification, which is conducive to the full automation of shrimp processing.

Equid alphaherpesvirus 1 (EHV-1) has been linked to the emergence of neurological disorders, with the horse racing industry experiencing significant impacts from outbreaks of equine herpesvirus myeloencephalopathy (EHM). Building robust immune memory before pathogen exposure enables rapid recognition and elimination, preventing infection. This is crucial for effectively managing EHV-1. Removing neuropathogenic factors and immune evasion genes to develop live attenuated vaccines appears to be a successful strategy for EHV-1 vaccines. We created mutant viruses without ORF38 and ORF37/38 and validated their neuropathogenicity and immunogenicity in hamsters. The ∆ORF38 strain caused brain tissue damage at high doses, whereas the ∆ORF37/38 strain did not. Dexamethasone was used to confirm latent herpesvirus infection and reactivation. Dexamethasone injection increased viral DNA load in the brains of hamsters infected with the parental and ∆ORF38 strains, but not in those infected with the ∆ORF37/38 strain. Immunizing hamsters intranasally with the ∆ORF37/38 strain as a live vaccine produced a stronger immune response compared to the ∆ORF38 strain at the same dose. The hamsters demonstrated effective protection against a lethal challenge with the parental strain. This suggests that the deletion of ORF37/38 may effectively inhibit latent viral infection, reduce the neuropathogenicity of EHV-1, and induce a protective immune response. [ABSTRACT FROM AUTHOR]

Objectives To characterize bla NDM-carrying Salmonella recovered from a pig slaughterhouse. Methods In this study, 46 environment samples were collected from a slaughterhouse in China, and screened for carbapenem-resistant Enterobacterales. WGS, antimicrobial susceptibility testing and conjugation experiments were carried out to identify the isolates' resistance phenotypes and genetic characteristics. The phylogenetic relatedness of the Salmonella isolates obtained in this study and Salmonella (ST34 and ST29) in GenBank was determined. Results Two ST34 Salmonella Typhimurium and one ST29 Salmonella Stanley, recovered from three environmental samples (6.52%), were positive for bla NDM-1 and bla NDM-5, respectively. The two ST34 S. Typhimurium strains exhibited a close relationship (10–36 SNPs) with two human-derived bla NDM-1-bearing isolates from China (Hong Kong and Guangxi Province) and two bla NDM-negative ST34 Salmonella strains from the UK. The bla NDM-1 genes were located on IncHI2/ST3 plasmids. The capture of bla NDM-1 by the IncHI2/ST3 plasmid seems to be due to homologous recombination mediated by circular structures, as the genetic arrangements of the bla NDM-1 gene contain two IS 26 elements of the same orientation. The bla NDM-5 gene was also carried by the IncHI2/ST3 plasmid, which shares highly similar structures with other bla NDM-5-bearing IncHI2/ST3 plasmids from other sources (fish, chicken, duck, human). Conclusions This is the first report of a bla NDM-5-carrying IncHI2/ST3 plasmid in Salmonella. The clonal spread of NDM-1-producing ST34 S. Typhimurium across human and animal-associated environments, and the widespread dissemination of epidemic bla NDM-5-carrying IncHI2/ST3 plasmids among Enterobacteriaceae in China indicate the potential of further dissemination of bla NDM among Salmonella , which poses a threat to public health. [ABSTRACT FROM AUTHOR]

A study published in the Journal of Antimicrobial Chemotherapy has identified the emergence of the mcr-8.1 gene in Citrobacter werkmanii, a type of bacteria commonly found in soil, water, retail meat, and the intestines of animals and humans. The mcr-8.1 gene, which is resistant to multiple antibiotics including colistin, was detected in drinking water and sewage samples from broiler farms in China. The study emphasizes the importance of proper sewage treatment and environmental sanitation in animal farms to prevent the spread and contamination of antibiotic-resistant bacteria. The research also suggests that C. werkmanii may act as a reservoir for the dissemination of antimicrobial resistance. [Extracted from the article]