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Abstract Utilizing steel slag aggregate (SA) as a substitute for river sand in 3D concrete printing (3DCP) has emerged as a new technique as natural resources become increasingly scarce. This study investigates the feasibility of using steel slag (SS) as fine aggregate for 3DCP. Ninety mixtures with varying steel slag aggregate-to-cement ratios (SA/C), water-to-cement ratios (W/C), and silica fume (SF) contents were designed to study the workability and compressive strength of the 3D-printed concrete. Additionally, the actual components were printed to evaluate the printability of these mixtures. The experimental results indicate that it is feasible to fully employ SA in concrete for 3D printing. Mixtures with slump values ranging from 40 to 80 mm and slump flow values varying from 190 to 210 mm are recommended for 3D printing. The optimal mix is determined to have SA/C and W/C ratios of 1.0 and 0.51, respectively, and an SF content of 10% by cement weight. A statistical approach was utilized to construct the prediction models for slump and slump flow. Moreover, to predict the plastic failure of the 3D-printed concrete structure, the modified prediction model with an SA roughness coefficient of 4 was found to fit well with the experimental data. This research provides new insights into using eco-friendly materials for 3D concrete printing.

Cross-border e-commerce(CBEC) has created enormous economic benefits for consumers and vendors worldwide. Vietnamese Small and Medium-sized Enterprise (SMEs) can enhance their competitiveness and facilitate their integration into the global market via cross-border e-commerce adoption. This study assesses the critical determinants of cross-border e-commerce adoption intention in Vietnamese SMEs. This study integrates the factors of the technology–organisation–environment (TOE) framework and the theory of planned behaviour (TPB) to construct a holistic framework to assess the critical determinants of cross-border e-commerce adoption intentions among SMEs in Vietnam. The research method utilised Structural Equation Modelling Partial Least Squares (SEM-PLS) with SmartPLS (version 4.0) to evaluate the relationship between variables. The sample size consists of 400 respondents from Vietnamese SMEs. The results indicate that perceived behavioural control, subjective norms, and attitudes toward CBEC adoption are the critical determinants of cross-border e-commerce adoption intention among Vietnamese SMEs. For the technological dimensions of the TOE framework, perceived benefits, perceived compatibility and perceived security positively relate to attitude toward CBEC adoption; perceived complexity and perceived cost negatively relate to attitude toward CBEC adoption and perceived behavioural control. For the organisational dimensions of the TOE framework, government support, customer pressure, and competitive pressure positively relate to subjective norms. For the environmental dimensions of the TOE framework, organisational readiness, organisational innovativeness, and e-commerce knowledge positively relate to perceived behavioural control. By integrating the constructs of TPB and TOE into a single framework, this study adds to current knowledge by addressing the literature gap on the significant role of organisational and environmental factors in the adoption of SMEs' CBEC in developing countries like Vietnam. The managerial implications provided a holistic view of SMEs' perspectives and practices on promoting the CBEC adoption intention.

This research aimed to investigate the determinants of panic purchasing to hoard food in Ho Chi Minh City during the lockdown caused by the COVID-19 pandemic. Pragmatism and the deduction approach were used for the research. During the lockdown period in Ho Chi Minh City, the purposive sampling technique was the first method used to reach the population that needed to be measured. Then, simple sampling was the second technique to collect data in the city in July and August 2021. Data were collected from 584 participants—higher than the required minimum sample size—who fulfilled the essential criteria to be included in the sample’s population. Multi-quantitative methods, including descriptive statistics, reliability tests for items, exploratory factor analysis, and linear regression analysis, were used to analyze the data obtained. The main findings are that perceived scarcity, susceptibility, severity, cues to action, and self-efficacy impacted panic purchasing to hoard foods. The results of this study are compared to the literature review in order to discuss panic buying behaviour, and recommendations are offered to policymakers and researchers in the future.

This study aims to assess the impacts of three components from Theory of Planned Behaviour (TPB) on Entrepreneurial intention and analyze the mediating effects of these three components in the relationship between Entrepreneurial education and Entrepreneurial intention and in the relationship between Self-Efficacy and Entrepreneurial intention among engineering students. Data were collected via a structured questionnaire from engineering students at Industrial University of Ho Chi Minh City in Vietnam. The methodology employed Structural Equation Modelling Partial Least Squares (SEM-PLS) using SmartPLS (version 3.3.3) to assess the relationship among variables. Findings confirm the directly positive relationship between Attitude toward entrepreneurship, Perceived behaviour control and Subjective norms on engineering student’s entrepreneurial intention. These three components of TPB mediate the relationship between Entrepreneurial education, Self-Efficay and engineering student’s entrepreneurial intention. This study contributes toward the understanding of engineering student’s entrepreneurial intention in Vietnam as an emerging market in Asia. The mediating effects of three components of TPB have been systematically investigated and the indirect roles of Entrepreneurial education and Self-Efficay have been validated by applying employed Structural Equation Modelling Partial Least Squares (SEM-PLS). Managerial implications are discussed to promote engineering student’s entrepreneurial intention in Vietnam. Higher education leaders and policymakers can utilise the findings to construct the initiatives of entrepreneurship development and their implementation for engineering students.

The phytochemical constituents from the roots of Millettia speciosa were investigated by chromatographic isolation, and their chemical structures were characterized using the MS and NMR spectroscopic methods. A total of 10 compounds, including six triterpenoids, two flavonoids, and two phenolic compounds, were identified from the roots of M. speciosa. Out of the isolated compounds, eight showed inhibitory effects on NO production in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells, with IC50 values ranging from 43.9 to 449.5 µg/mL. Ursane-type triterpenes significantly suppressed NO production compared to the remaining compounds. In addition, these compounds also exhibited remarkable inhibitory effects on α-glucosidase. Among the tested compounds, 4, 5, and 10 exhibited excellent α-glucosidase inhibition, with IC50 values ranging from 1.1 to 2.2 µg/mL. Almost all of the test compounds showed little or no acetylcholinesterase inhibition, except for 5, which showed moderate anti-acetylcholinesterase activity in vitro. The molecular docking study of α-glucosidase inhibition by 3–5 and 10 was conducted to observe the interactions of these molecules with the enzyme. Compounds 4, 5, and 10 exhibited a better binding affinity toward the targeted receptor and the H-bond interactions located at the entrance of the enzyme active site pocket in comparison to those of 3 and the positive control acarbose. Our findings evidence the pharmacological potential of this species and suggest that the phytochemicals derived from the roots of M. speciosa may be promising lead molecules for further studies on the development of anti-inflammatory and anti-diabetes drugs.