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Digital transformation has been inevitable in all socio-economic fields, including higher education. Recently, under the burden of the COVID-19 pandemic, many universities have to change their entire teaching systems to online learning to ensure their students' learning is not interrupted. Thus, it is essential to study how universities' students, educators, and administrators perceive online learning in different countries. To this aim, this study investigates the factors affecting university members' preference for online learning in Singapore and Vietnam. Using a cross-country sample with a sound theoretical framework of the Technology Acceptance Model (TAM), we found that each member group in the university was influenced by a different weight of factors. Specifically, students' preference for online learning is most affected by their technical skills. Meanwhile, educators and administrators are influenced mainly by the perceived usefulness of online learning and practice conditions, respectively. We further conducted multi-group testing and confirmed the certain separation in online learning preferences of observed objects between the two countries. Overall, this paper enriches the literature on online education, and has important implications for educational policymakers and university stakeholders both during and after the pandemic.

Anthracnose in citrus is a severe disease caused by Colletotrichum species. Synthetic fungicides have been used to combat this citrus disease; however, they may have adverse health effects on humans and cause harmful environmental impacts. During a search for environmentally friendly fungicides, we successfully prepared organic copper (copper (II) oleate) nanoparticles by using natural chitosan polymer as a coating agent and stabilizer and by combining an exchange reaction and in situ coating method. Organic copper nanoparticles coated with chitosan polymer (Cu‐oleate@CS NPs) with Cu contents ranged from 5.0 to 6.0 % by weight. The nanoparticles have an average particle size ranging from 50 nm to 60 nm (TEM), covered by a layer of polymer with a thickness of about 10 to 12 nm. The analytical results of zeta potential and dynamic solution size showed that the nanoparticles are uniformly dispersed (90–120 nm by DLS), with high stability (zeta potential=−61.7 mV) and low cytoxicity to Vero healthy cell line. Cu‐oleate@CS NPs significantly inhibited the mycelial growth of C. gloeosporioides in vitro at 500 and 1000 μg/mL. In field trials, the best antifungal efficacy of Cu‐oleate@CS NPs against citrus anthracnose on orange plants was found at a spray concentration of 0.33 % with a disease control efficacy of 54.18 % at 14 days after the second spraying. Our study results demonstrated a novel preparation of Cu‐oleate@CS NPs and suggested that it could be used as a promising nanoformulation to control citrus anthracnose in vitro and in vivo. [ABSTRACT FROM AUTHOR]