PMC:7796329 / 68691-68779 JSONTXT

{"project":"LitCovid-sentences","denotations":[{"id":"T569","span":{"begin":0,"end":88},"obj":"Sentence"}],"namespaces":[{"prefix":"_base","uri":"http://pubannotation.org/ontology/tao.owl#"}],"text":"Because the three factors have very different properties, various approaches are needed."}