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This study aims to study the distribution characteristics of antibiotic resistance in direct-eating food and analysis of Citrobacter freundii genome and pathogenicity. Residual antibiotics and antibiotic resistance genes (ARGs) in the environment severely threaten human health and the ecological environment. The diseases caused by foodborne pathogenic bacteria are increasing daily, and the enhancement of antibiotic resistance of pathogenic bacteria poses many difficulties in the treatment of disease.

In this study, six fresh fruits and vegetable samples were selected for isolation and identification of culturable bacteria and analysis of antibiotic resistance. The whole genome of Citrobacter freundii isolated from cucumber was sequenced and analyzed by Oxford Nanopore sequencing.

The results show that 270 strains of bacteria were identified in 6 samples. From 12 samples of direct food, 2 kinds of probiotics and 10 kinds of opportunistic pathogens were screened. The proportion of Citrobacter freundii screened from cucumber was significantly higher than that from other samples, and it showed resistance to a variety of antibiotics. Whole genome sequencing showed that Citrobacter freundii was composed of a circular chromosome containing signal peptides, transmembrane proteins and transporters that could induce antibiotic efflux, indicating that Citrobacter freundii had strong adaptability to the environment. The detection of genes encoding carbohydrate active enzymes is more beneficial to the growth and reproduction of Citrobacter freundii in crops. A total of 29 kinds of ARGs were detected in Citrobacter freundii, mainly conferring resistance to fluoroquinolones, aminoglycosides, carbapenem, cephalosporins and macrolides. The main mechanisms are the change in antibiotic targets and efflux pumps, the change in cell permeability and the inactivation of antibiotics and the detection of virulence factors and ARGs, further indicating the serious risk to human health.

The detection of genomic islands and prophages increases the risk of horizontal transfer of virulence factors and ARGs, which spreads the drug resistance of bacteria and pathogenic bacteria more widely.

To date, research on migration and entrepreneurship has rarely focused expat-preneurs. Based on recent developments in both fields, this paper aims to investigate the under-researched phenomenon of Chinese self-initiated expatriates who choose to temporarily live and do business abroad on their own volition.

To address this research gap, 15 in-depth semi-structured interviews with Chinese expat-preneurs living in Portugal were conducted, exposing their narratives about their multiple challenges.

The findings corroborate the theoretical need to look beyond narrow economic explanations for why individuals engage in transnational entrepreneurship and entrepreneurial itinerancy. A collective identity and ethnic community are important because they influence how opportunities are identified and pursued.

This is a qualitative and interpretative study in a limited geographical area, which does not intent to ensure generalizability. More research is needed to further understand the phenomenon of entrepreneurial itinerancy in Europe and among other ethnic communities.

The findings provide insightful inputs to Portuguese policymakers and locals on how to support ethnic entrepreneurship. Chinese expat-preneurs also benefit from understanding how to strength their ethnic social ties in connection with local communities.

This study contributes to the entrepreneurship and international mobility literatures by providing new insights into the nature and dynamics of Chinese “expat-preneurs”, including their entrepreneurial itinerancy, necessary to properly understand entrepreneurs’ diversity and assist in extending transnational entrepreneurial theory.

The purpose of this study is to prolong the service life of the Al–Si alloy cylinder and achieve the objective of energy saving and emission reduction by the composite treatments.

Chemical etching + laser texturing + filled MoS₂ composite treatment was applied to the friction surface of aluminum–silicon (Al–Si) alloy cylinder. The friction coefficient and wear loss were measured to characterize the tribology property of cylinders.

The composite-treated Al–Si alloy cylinder had the lowest friction coefficient and weight loss. The friction coefficient and weight loss of the composite treatment were approximately 27.08% and 54.17% lower than those of the untreated sample, respectively. The laser micro-textures control the release of solid lubricant to the interface of friction pairs slowly, which prolongs the service life of cylinders.

The synergistic effect of the chemical etching + laser texturing + filled MoS2 modified the tribology properties of Al–Si alloy cylinder. The chemical etching raised the silicon particles to bear the load, and laser micro-textures control the release of solid lubricant to improve the lubrication property.

The silicone modifications of two-component epoxy resin coatings are commonly built on epoxy resins rather than on epoxy curing agents. The silicone-modified epoxy curing agent system is rarely reported yet. This study aims to prepare the polysiloxane (PS)-modified waterborne epoxy coatings based on aqueous curing agents technology.

Waterborne epoxy curing agents with different contents of terminal epoxy PS were synthesized by reacting with triethylenetetramine, followed by incorporating of epoxy resin (NPEL-128) and polyethylene glycol diglycidyl ether. The waterborne epoxy coatings were prepared with the above curing agents, and their performance was investigated through thermogravimetric analysis, scanning electron microscopy, mechanical characterization, gloss measurement, chemical resistance test and ultraviolet (UV) aging experiment.

The results showed that the epoxy coating prepared by silicon-modified curing agent has higher gloss, better chemical resistance and UV resistance than the coating from unmodified curing agent with terminal epoxy PS and commercially available waterborne epoxy curing agent (Aradur 3986), as well as the competitive mechanical properties and heat resistance. Reduced water absorption on fibrous paper was also obtained with the help of silicon-modified curing agent.

These findings will be valuable for resin researchers in addressing the modification issues about waterborne epoxy resin and curing agent.

The purpose of this paper is to study the profit optimization of manufacturers who provide personalized products to customers, thus avoiding additional operational costs and response times in the production process of personalized product design.

First, the authors present an integrated model for optimizing profit where the design and production of personalized products are both considered. The authors propose the concept of personalization level and four cases of personalization level are considered including top, high, medium and low levels. Polynomial-time optimal rules are provided for each level by analyzing 17 subcases where all possible personalized products are considered. Then, the authors compare the obtained profit of personalized products with the optimal profit of standardized products.

At low and high levels of personalization, personalized manufacturing is more profitable for specific products with specific characteristics. At the top and middle level of individuation, assuming that the product has certain characteristics, whether the best choice to produce personalized products depends on the level of individuation chosen by customers.

An important decision issue for manufacturers is whether to produce personalized or standardized products. In this study, the authors consider this decision problem and analyze the operational functions of personalized products. The authors hope to provide theoretical support in the operational management of manufacturers offering personalized products.

Numerous studies have shown that minority workers are disadvantaged in the labour market due to stereotypes and discrimination. However, published research on résumé screening has overlooked the effects of multiple social categorisations pertaining to candidates' gender, education and origin. This study addresses this gap and examines whether the gender, the level of education and the national origin cues mentioned in the résumé affect the perceived employability of candidates.

This study employs an experimental between-subjects factorial design in that 12 résumés varying in gender, education and national origin were rated by 373 Portuguese working adults.

The results documented a gender premium as women were favoured in interpersonal and job skills but not in job suitability, and an education premium, since higher educated candidates were preferred despite their gender and origin. No meaningful interactions for gender × education × national origin were observed, which suggests that ingroup favouritism and outgroup discrimination in résumé screening can be averted.

The findings endorse a multidimensional view of perceived employability by investigating candidates' skills and job suitability from the viewpoint of the decision-makers, which extends our understanding of résumé-screening discrimination. This is critical to prevent hiring discrimination at an earlier career stage, which can increase youth employment and enhance the integration in the labour market of local minorities such as women, inexperienced workers and second-generation immigrants.