2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/8403In the present paper we report on first results of a project in Brussels where we study the effects of stellar dynamics on the evolution of young dense stellar systems using the 3 decades expertise in massive star evolution and our population (number and spectral) synthesis code. We highlight an unconventionally formed object scenario (UFO-scenario) for Wolf Rayet binaries and study the effects of a luminous blue variable-type instability wind mass loss formalism on the formation of intermediate mass black holes.4 pages, 2 figures, proceeding of the conference Massive Stars in Interacting Binaries, eds. N. St-Louis and A. MoffatAstrophysicstext