The work in this thesis involves detailed multi-frequency radio continuum (from 325 MHz to 15 GHz) and Hi spectroscopic studies of a few represent tative nearby galaxies which are experiencing gas-loss from their disks ...

It is evident that the origin of EGRB is not well established. In this thesis I examine the unresolved discrete origin of EGRB. The contribution from normal galaxies, starburst galaxies and AGNs to the EGRB is examined. ...