2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/131343We explicit Ozawa kernels for classical group theoretical constructions, for discrete metric spaces of finite asymptotic dimension, of large enough Hilbert space compression, and for suitable actions of countable groups on metric spaces. We also obtain an alternative proof of stability results concerning Yu's property A.17 pagesGroup TheoryOperator Algebras43A35; 20F65; 46L80; 20E06text