URS (Universe of RNA Structures) allows users to select a set of RNA containing PDB documents and view various statistics of structural elements from the set. The work on the URSDB (URS DataBase) started in 2011 in Institute of Mathematical Problems of Biology of Russian Academy of Sciences. Since 2014 URS is available online.
Eugene Baulin, Victor Yacovlev, Denis Khachko, Sergei Spirin, Mikhail Roytberg
baulin@lpm.org.ru (Eugene Baulin), mroytberg@lpm.org.ru (Mikhail Roytberg)