Only some parts of the perdurant p have a participant e.In fact, participation can be constant (in all parts of the perdurant, e.g. in 'the car is running'), or temporary (in only some parts, e.g. in 'I'm electing the president').Implicitly, this relation has a temporal indexing.If needed, in OWL one can derive such indexing by expliciting what parts of p have e as _constant_ participant.An appropriate OWL axiom is created to bind this relation to a proper part of it, which has the temporary-participant as a constant one.