HIPPARCOS trigonometrical parallaxes are given for 16 pre-selected Mira variables. Linear diameters are derived for 8 oxygen-rich Miras with known angular diameters. Comparison with pulsation theory shows that two of them (both with periods over 400 day) are fundamental pulsators, the others (all with periods less than 400 day) pulsate in an overtone. The Mira PL relations in M K and M bol are calibrated for oxygen-rich overtone pulsators adopting slopes for these relations from LMC data. A mean LMC distance modulus of 18.54 is derived this is very close to that of 18.57 derived from the Cepheids. The uncertainty in the value derived from the Miras is estimated to be less than 0.2 mag. The absolute magnitude of the only carbon-rich Mira in the sample, R Lep (period of 427 day), indicates that it is a fundamental pulsator. Other stars discussed individually are: the symbiotic Mira, R Aqr the double-period Mira, R Cen and, two Miras with decreasing periods, R Aql and R Hya.

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Abstract.A highly and rapidly variable bipolar mass outflow from StHα 190 has been discovered, the first time in a yellow symbiotic star. Permitted emission lines are flanked by symmetrical jet features and multi-component P-Cyg profiles, with velocities up to 300 km s −1 . Given the high orbital inclination of the binary, if the jets leave the system nearly perpendicular to the orbital plane, the de-projected velocity equals or exceeds the escape velocity (1000 km s −1 ). StHα 190 looks quite peculiar in many other respects: the hot component is an O-type sub-dwarf without an accretion disk or a veiling nebular continuum and the cool component is a G7 III star rotating at a spectacular 105 km s −1 , unseen by a large margin in field G giants.