2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/48811This article, in memory of Professor Hiroshi Suura, is devoted to the effects of particles in loops, ranging from quantum electrodynamics to precise tests of the electroweak theory and CP violation.16 pages, latex, no figures, to be published by the Japan Physical Society in a memorial collection for Hiroshi SuuraHigh Energy Physics - Phenomenologytext