A relationship between a continuant and an occurrent, which holds iff at every time an instance of the continuant is created, it participates in atleast one instance of the occurrent at the same time.

Scanning Electron Microscope participates_in Scanning Electron Microscopy

Smith B, Ceusters W, Klagges B, Kohler J, Kumar A, Lomax J, Mungall C, Neuhaus F, Rector AL, Rosse C: Relations in biomedical ontologies. Genome Biol 2005, 6: R46.