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Oxygen abundances of a large number of metal-rich stars, with and without known planets, were derived from the forbidden line [O I] 6300 Å, the OI 7771-5 Å triplet and from near-UV OH lines. Non-LTE corrections were calculated and applied to the LTE abundance results derived from the OI 7771-5 Å triplet. Spectral synthesis was performed for several

OO Serpentis is a deeply embedded young star which brightened by 5 mag in Kband between 1994 and 1995, and gradually faded afterwards. In many respects the star and its outburst is very similar to the well-known young eruptive stars (FUors and EXors). We monitored the eruption of OO Ser for 20 months with the Infrared Space Observatory in the 3.6

Using high resolution optical spectroscopy (R˜40,000-50,000) we have derived the Li and Zr abundances of a large sample of galactic O-rich AGB stars. Our chemical analysis shows that some stars are Li overabundant while others are not. The observed Li overabundances are attributed to the activation of the so-called ``hot bottom burning'' (HBB)

AGB stars, in particular those of carbon types, are excellent laboratories to constraint the theory of stellar structure, evolution and nucleosynthesis. Despite the uncertainties still existing in the chemical analysis of these stars, the determination of the abundances of several key species in their atmospheres (lithium, s-elements, carbon and

We are currently undertaking a systematic search of new Galactic planetary nebulae (PNe) in the IPHAS (INT Photometric H-Alpha Survey) data. We employ two methods to search for PNe of different sizes: a visual search through continuum subtracted H-Alpha mosaics for extended PNe and a (point) source catalog based search for small diameter PNe. Here