UV observations of some massive globular clusters uncovered a significant population of very hot stars below the hot end of the horizontal branch, the so-called blue hook stars. This feature might be explained either by the late hot flasher scenario where stars experience the helium flash while on the white dwarf cooling curve or by the helium-rich

We review the properties of multiplicity of very low mass stars and brown dwarfs in different environments and at different ages. We will compare the main results of surveys performed in the field, where the objects are relatively old (1-5 Gyrs) and isolated, in the Pleiades young (~120 Myr) open cluster, and in the young (~5 Myr) Upper Scorpius OB

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Given the many recent advances in our understanding of the star formation history (SFH) of the Local Group and other nearby galaxies, and in the evolution of star formation with redshift, we present a new comparison of the comoving space density of the star formation rate as a function of look-back time for the Local and Distant Universe. We update

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