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ObjectiveTo analyze the contamination and drug resistance characteristics of Bacillus cereus isolated from raw vegetable.MethodsOne hundred and twenty raw vegetable samples were collected in this study in Beijing City， Shuiyi District from May to September in 2021. Plate counting， bacterial culture， real-time PCR for the ces vomiting toxin gene and the 16S rDNA gene of B. cereus were performed. Drug resistance to 14 antibiotics in B. cereus strains were determined.ResultsThe positive ratios of B. cereus in raw vegetable samples was 84.17% （101/120）. Significant differences were observed in the positive ratio of B. cereus between rhizome and leaf vegetables （χ2=14.181， P=0.000 correction）， in the positive ratio of B. cereus （χ2=11.050， P=0.004） in supermarkets， agricultural markets， and farmland， and also in the positive ratio of ces on enriched samples （P=0.001 Fisher）. Average Ct values of 16S rDNA and ces by real-time PCR in 12 ces+ enriched samples were 19.96 and 31.80， respectively； however， ces+ B. cereus was not isolated. The drug resistance ratios of B. cereus isolates to AMP， PEN， and SXT were 100%， 99.01%， and 61.39%， respectively. Five patterns of drug resistance distribution were observed and the dominant pattern was AMP+PEN+SXT （59.41%）； the multidrug resistance ratio （resistant to three or more classes of antibiotics） was 0.99% （1/101）.ConclusionB. cereus and the ces gene were widely distributed in local raw vegetable samples with a low level of multiple drug resistance in the isolates. ces+ B. cereus was present in low proportions in the B. cereus flora in s single sample of raw vegetable.

Research experience is widely used in quality assurance exercises to benchmark postgraduate education at the institutional level. However, individual differences in students' research experience have been largely neglected. Furthermore, little is known about how differences in students' research experience are associated with skill development and overall satisfaction. This study addressed these gaps using an explanatory sequential mixed-methods design. Study 1 was a quantitative study that involved surveying 590 research postgraduate students (i.e. 421 PhD and 168 MPhil students). A person-centered approach, specifically latent profile analysis, was used to analyze the data. Our findings revealed that students could be divided into three groups based on their research experience: rewarding, ordinary, and unsatisfactory. Those with a rewarding research experience experienced greater development in their skills and higher levels of satisfaction, while those in the unsatisfactory group demonstrated the worst outcomes. Study 2 was a qualitative study that involved interviews with 10 PhD students. The qualitative findings largely triangulated the quantitative results but also uncovered emerging themes, including the importance of student-supervisor misfit, publication pressure, and the COVID-19 pandemic context. Theoretical and practical implications of these findings are discussed.

This paper reconceptualised the interrelated learning constructs in higher education based on the Dynamic Systems Theory (DST). The university students' learning experience before, during and post the Emergency Online Learning (EOL) was investigated to explore the dynamic changes among the learning constructs in higher education. A case study of a Chinese university was conducted, and one hundred and ninety-three university students participated in the questionnaire. The data collected from this empirical research identify different hierarchical constructs of the conceptualised learning environment and reconceptualise the period of system reformation influenced by the EOL. The key findings include the identifications of the attractors and repellors framed by the DST and the impact on the changes in the learning constructs. The results of this paper contribute to further understanding of the university constructs' changes to better plan and support students' active learning in higher education.

As one of the core skills of the 21st century, computational thinking has received increasing attention from educators and researchers. Although some research has been conducted on computational thinking, few studies examined the impact of learning activities on students' computation thinking skills from the perspective of cognitive development. Based on the theory of scaffolding instruction, a progressive thinking training approach with flowcharts was proposed to cultivate students' computational thinking skills. A quasi-experiment was designed to evaluate the effectiveness of the training. Forty-nine Chinese tertiary students undertaking a programming course were randomly assigned into two groups -- the experimental and control groups. During the course, the experimental group received progressive training, and the control group received non-progressive training. The results showed that the experimental group gained a significantly higher level of academic achievement than the control group. Meanwhile, the experimental group showed a remarkable improvement in programming self-efficacy. Furthermore, the participants in the experimental group showed a higher level of computational thinking skills, including cooperative learning, critical thinking, and problem solving skills. In summary, the progressive thinking training approach with flowcharts could not only improve the participants' computational thinking skills and programming self-efficacy, but also help them to achieve better academic outcomes.