"x existence overlaps y if and only if either (a) the start of x is part of y or (b) the end of x is part of y. Formally: x existence starts and ends during y iff (\u03B1(x) >= \u03B1(y) & \u03B1(x) <= \u03C9(y)) OR (\u03C9(x) <= \u03C9(y) & \u03C9(x) >= \u03B1(y))" . . "existence overlaps" . "The relations here were created based on work originally by Fabian Neuhaus and David Osumi-Sutherland. The work has not yet been vetted and errors in definitions may have occurred during transcription." . . "Chris Mungall" .