somewhat lower than other well studied starburst galaxies such as Arp220 [f$_{15\mu m}$/f$_{6.7\mu
m}$$\sim$3.9, @Charmandaris1999b] or the extremely strong starburst region in the Cartwheel [f$_{15\mu m}$/f$_{6.7\mu
m}$$\sim$5.2, @Charmandaris1999a]. This effect can be understood since the hot continuum produced by an AGN at short MIR wavelengths would cause the flux in the 6–10$\mu$m range to increase more relative to the increase observed between 12–16$\mu$m and as result it would be added the UIB emission sampled by the LW2 filter.

Could the large difference in the MIR brightness between the north and south component in IRAS19254-7245 be related to the additional contribution of the AGN? Studies of the dynamical evolution of this system suggest that the starburst time scale is much shorter than the dynamical age of the merger [@Mihos1998]. Even though we can not quantify accurately the fraction of MIR luminosity due to the AGN activity, it appears that the southern component of IRAS19254-7245 has reached an AGN dominant phase, however short this may be, after an initial phase of strong starburst activity (see @Laurent2000 and @Genzel1998 for details on the MIR AGN/starburst fraction of this and other galaxies). The MIR properties of the northern nucleus are similar to a normal 