The incubation period from infection to symptoms or a first positive COVID-19 test has decreased as the coronavirus has evolved, dropping from 5 days to 3.5 days, according to a new study published in JAMA Network Open.
Researchers in China analyzed 142 studies published between December 2019 and February 2022. The studies included data about more than 8100 COVID-19 patients.
Chinese scientists have developed an ultralight solar cell with perovskite film based on a 3-µm-thick polymer. It purportedly has a power conversion efficiency in line with that of perovskite cells of