Abstract: The disclosure provides, in various embodiments, polypeptides (e.g., antibodies and antigen binding fragments thereof) that specifically bind to S2 domains of betacoronavirus Spike glycoproteins, such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Spike glycoproteins. The disclosure also provides, in various embodiments, fusion proteins comprising one or more of polypeptides, polynucleotides encoding polypeptides, vectors and host cells suitable for expressing polypeptides, and methods for treating viral infections (e.g., COVID-19).

Abstract: The disclosure is about a method capable of realizing the preparation and in-situ separation of the oligomeric ricinoleate, which uses the ricinoleic acid as raw material, and uses a protonic acid-type ionic liquid as a catalyst to cause the dehydration and esterification reactions between ricinoleic acid molecules. By continuously distilling out the generated water under a reduced pressure, the oligomeric ricinoleate with a polymerization degree of 2 to 10 is obtained. After the reaction, a method of washing with water or static stratification is selected to recover the catalyst according to the miscibility of the catalyst and reaction system. In his disclosure, renewable raw materials are used, the process is clean and pollution-free, and the operation is simple.