We have analyzed the differences in the oscillation eigenfrequencies measured in the last three years of GONG (From September 1996 to August 1998) observations and 2 years of SOI/MDI (from May 1996 to May 1998) observations. We have inverted these data to look for signatures of the solar activity cycle on the stratification. A one-dimensional

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We present new monitoring observations of the BL Lac object 3C66A, taken between the years 1995-1997. During this period the object was always observed in an outburst phase, which started in 1993. Only towards the end of this observing period the brightness level started to decrease, suggesting that the outburst is probably over. Characteristic to

The preliminary results of a classical spectroscopic analysis of a facular region at mu=0.78 of ~100 arcsec x 50 arcsec are presented. The variation with magnetic activity of several spectroscopic parameters has been studied, showing clear evidence that granulation properties are modified.