Isolated spectral points and Koliha-Drazin invertible elements in   quotient Banach algebras and homomorphism ranges
  In this article poles, isolated spectral points, group, Drazin and Koliha-Drazin invertible elements in the context of quotient Banach algebras or in ranges of (not necessarily continuous) homomorphism between complex unital Banach algebras will be characterized using Fredholm and Riesz Banach algebra elements. Calkin algebras on Banach and Hilbert spaces will be also considered. 
Enrico Boasso
math.FA