PubMed Commons closes its doors to comments

"The US National Institutes of Health (NIH) announced on 1 February that it will discontinue PubMed Commons, a tool that allows scientists to comment on articles indexed in the agency’s popular PubMed database of biomedical literature. The agency said that low levels of engagement and the growth of alternate venues for public discussion of published papers contributed to its decision to close PubMed Commons after five years."