ABSTRACT
The outbreak and pandemic of COVID-19, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has developed into a public health emergency of international concern. The rapid and accurate detection of the virus is a critical means to prevent and control the disease. Herein, we provide a novel, rapid, and simple approach, named dual reverse transcriptional colorimetric loop-mediated isothermal amplification (dRT-cLAMP) assay, to accelerate the detection of the SARS-CoV-2 virus without using expensive equipment. The result of this assay is shown by color change and is easily detected by the naked eye. To improve the detection accuracy, we included two primer sets that specifically target the viral orf1ab and N genes in the same reaction mixture. Our assay can detect the synthesized SARS-CoV-2 N and orf1ab genes at a low level of 100 copies/µL. Sequence alignment analysis of the two synthesized genes and those of 9968 published SARS-CoV-2 genomes and 17 genomes of other pathogens from the same infection site or similar symptoms as COVID-19 revealed that the primers for the dRT-cLAMP assay are highly specific. Our assay of 27 clinical samples of SARS-CoV-2 virus and 27 standard-added environmental simulation samples demonstrated that compared to the commercial kits, the consistency of the positive, negative, and probable clinical samples was 100, 92.31, and 44.44%, respectively. Moreover, our results showed that the positive, but not negative, standard-added samples displayed a naked-eye-detectable color change. Together, our results demonstrate that the dRT-cLAMP assay is a feasible detection assay for SARS-CoV-2 virus and is of great significance since rapid onsite detection of the virus is urgently needed at the ports of entry, health care centers, and for internationally traded goods.
ABSTRACT
Under the circumstance of COVID-19, online education has become an inevitable choice and a mainstream form of education in various countries. Intelligent Tutoring Systems ( ITSs ) are a critical category of a carrier of online education which refers to using Artificial Intelligence Technology ( AIT ) to realize distance teaching and learning through integrating multiple resources, assist teachers to implement online classes and help students learn courses online, etc. The target of this study is to examine the determinants that explain college students? adoption of ITSs based on TRA and TAM under the era of COVID-19 in China.. This study targets college students who have used ITSs over the previous year to learn courses. In total, 590 valid samples were collected. Partial least squares ( PLS ) approach is employed to inspect the determinants of college students? acceptance of using ITSs. The results of the analysis indicate that perceived ease of use, perceived usefulness, subjective norm, college students? attitude and political influence significantly affect college students? behavioral intention towards using ITSs. In addition, perceived usefulness, perceived ease of use, and political influence also affect college students? attitude toward using ITSs. And consisitent with previous research, perceived ease of use has a significant effects on perceived usefulness. This study enriches the TRA and TAM theories by incorporating a new variable political influence for researchers to consider in the future. In addition, it makes several suggestions for system developers to improve system functions regarding its ease of use and for content manufactures to pay attention to quality regarding usefulness. Recommendations are provided to colleges, universities and education authorities to rethink their roles in reforming online education through ITSs.
ABSTRACT
During the COVID-19 pandemic, Online Tutoring Platforms (OTPs) have been applied extensively in education in China. The aim of this study is to investigate the determinants that influence college students? behavioural intention of using OTPs to acquire knowledge. This study also explores how students? attitude change in using OTPs five months after the outbreak of the COVID-19 pandemic based on a hierarchical component model which is combined by the Social Impact Theory (SIT) and Unified Theory of Acceptance and Use of Technology (UTAUT). Partial least squares (PLS) analysis is employed to analyse the data collected from 1133 students in Mainland China. The results of the analysis indicate that social impact consists of three dimensions (compliance, identification, internalization) significantly influences college students? attitude toward OTPs and further affects college students? behavioural intention toward OTPs usage. Furthermore, performance expectancy and effort expectancy also positively affect students? behavioural intention toward using OTPs to acquire knowledge. This study makes several suggestions for universities to encourage students using OTPs to cope with the situation of Covid-19 pandemic and for educators to promote online tutoring for reforming universities in the future.