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Selecting stars with previously measured or estimated rotational periods the authors measured Li equivalent widths in 8 stars of the Hyades late main sequence. Plotting log N(Li) against Rossby number the authors can separate the effects of temperature and rotation. They find for stars later than F8 increased depletion with longer period, at

The authors study the application of the phase retrieval algorithm suggested by Walker (1982) to 1-D short-exposure images obtained by infrared stellar speckle interferometry. To verify its performance, the algorithm has been tested previously with 1-D computer simulated speckle images.

The authors present the first astronomical images reconstructed from their autocorrelation functions using an improved version of the simulated annealing algorithm.

Type I post-main-sequence nebulae appear to be characterised by a range of unusual, and in certain cases extreme physical characteristics, including high velocity (and possibly high mass) outflows, and anomalous He, N, and C abundances; a feature which is almost certainly indicative of high mass nebular progenitors. The authors have acquired high

Image sharpening techniques applied to medium size telescopes (approximately 1 m) can improve their resolution by double. A new algorithm for recentering and selecting better quality images has been developed. The authors carried out a comparative study with other algorithms in terms of spatial resolution and photometric response. Conclusions are