ABSTRACT
During financial crises or other unexpected events, investors often seek to include lower-risk assets in their portfolios. Some assets are more sensitive than others to such phenomena. In the equities markets, adjustments tend to be made to the shareholdings of companies that are associated with a higher level of uncertainty. In this work, we explore the evolution of shareholder structure of various well-known companies in the technology sector during the COVID-19 pandemic and beyond. We model, as graphs, shareholder ownership data about twenty US-listed companies between 2020 and 2022. We use freely available tools to explore the bipartite interactions and generate a wide range of topologies that facilitate the identification of how shareholding structures have evolved during the pandemic. In addition, we study the role that some nodes play in the network topology and the process of change that is observed. Our findings include that (1) most investors reduced the amount invested in technology stocks during the pandemic and that these investments tended to bounce back in the post-pandemic era;(2) Vanguard Group, Inc., is the most influential investor in the network;(3) Apple has the highest market capitalization of all technology stocks for all quarters in this study, Microsoft Corp has a significantly lower market capitalization, but a significantly higher number of investors;and (4) While investors for Apple and Microsoft tend to be from London and New York, companies such as Oracle have investors from a variety of locations. © 2022 Copyright for this paper by its authors. Use permitted under Creative Commons License Attribution 4.0 International (CC BY 4.0).
ABSTRACT
Yerba mate (Ilex paraguariensis A.St. Hil) and jarilla (Larrea divaricata Cav.) leaves are commonly used as tea infu-sions in some Latin American countries. This study was con-ducted to evaluate the antioxidant activity (FRAP, ABTS, and DPPH) and the inhibitory potential of yerba mate and jarilla extracts on the 3CL protease (Mpro) from coronavirus SARS-COV-2 by a molecular docking approach. The main bioactive compounds present in the plant extracts were identified by HPLC-MS. According to the results, the extracts of yerba mate and jarilla showed high antioxidant activity in DPPH (> 91 %), ABTS (> 90 %), and FRAP (> 47 mg TE/g) assays. Additionally, the phenolic compounds present in yerba mate, quercetin-3-O-rutinoside (rutin) (-9.60 kcal/mol) and 3,4-dicaffeoylqui-nic acid (-8.20 kcal/mol) were more effective on Mpro than the antiviral drugs remdesivir and ribavirin. The compounds rutin and 3,4-dicaffeoylquinic acid have a high affinity and interaction with one of the catalytic residues Cys145 of Mpro. The glycosylation of phenolic compounds affects biological activities: positively anti-COVID-19 and negatively antio-xidant. The results suggest that extracts of yerba mate and jarilla leaves could enhance the body's antioxidant defenses and can be used to improve health.