The relatively large neutral hydrogen contents and enhanced density of companion galaxies around Seyfert 2 galaxies suggests that tidal interaction could play a major role in the evolution of Seyfert 2 galaxies. Recent observations of the distribution of neutral hydrogen in the active S0 galaxy NGC5252 have shown a disturbed morphology which

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CCD spectroscopic observations from [NeV] lambda3425A to [SIII] lambda9532A of the nucleus and circumnuclear region of the Seyfert 1 NGC 4253 are presented. The nucleus shows circumnuclear emission which is elongated 1.5 kpc to the north-east; the spectrum of this extranuclear emission is well fitted by HII region models with effective temperatures

We present optical photometry and spectroscopy of the nova-like variable V795 Her. The emission lines exhibit an extremely complex structure consisting of several time-variable emission and absorption components. We confirm the spectroscopic modulation of 0.1082d which we attribute to the orbital period of the system. The equivalent widths (EWs) of

The presence of giant shells or loops in giant H II regions is clear witness to the mechanical energy input from massive stars. Here we evaluate the impact that winds may have on the structure of giant nebulae and on their supersonic velocity dispersion. We follow the recent suggestion of Chu and Kennicutt to see whether a combination of a large