ABSTRACT
This study examines the core factors that determine consumer choices of distribution channels for fresh food during the COVID-19 pandemic, focusing on online distribution channels and the substitution patterns between online and offline distribution channels. Using 1436 responses to a survey conducted by Gallup Korea, a specialized survey agency in Korea, we adopted a multivariate probit model for the empirical analysis. The results show that consumers who pursued ease of use or had high awareness of online food delivery tended to choose online distribution channels for fresh food, unlike consumers who were sensitive to high quality or low prices. Consumers with high consumer spending, who are living in Seoul or a metropolitan area, have children of 10 years old or younger, and have a high educational level had positive relationships with the choice of an online distribution channel. Additionally, the estimates of the variance-covariance matrix showed a complementary relationship between large markets and small and medium-sized markets, with the possibility of a weak substitution effect between small and medium-sized markets and online distribution channels. © 2022 John Wiley & Sons Ltd
ABSTRACT
SARS-CoV-2 is mutating and creating divergent variants across the world. An in-depth investigation of the amino acid substitutions in the genomic signature of SARS-CoV-2 proteins is highly essential for understanding its host adaptation and infection biology. A total of 9587 SARS-CoV-2 structural protein sequences collected from 49 different countries are used to characterize protein-wise variants, substitution patterns (type and location), and major substitution changes. The majority of the substitutions are distinct, mostly in a particular location, and lead to a change in an amino acid's biochemical properties. In terms of mutational changes, envelope (E) and membrane (M) proteins are relatively more stable than nucleocapsid (N) and spike (S) proteins. Several co-occurrence substitutions are observed, particularly in S and N proteins. Substitution specific to active sub-domains reveals that heptapeptide repeat, fusion peptides, transmembrane in S protein, and N-terminal and C-terminal domains in the N protein are remarkably mutated. We also observe a few deleterious mutations in the above domains. The overall study on non-synonymous mutation in structural proteins of SARS-CoV-2 at the start of the pandemic indicates a diversity amongst virus sequences.