We report the discovery of a locus of stars in the SDSS g-r vs. u-g color-color diagram that connects the colors of white dwarfs and M dwarfs. While its contrast with respect to the main stellar ...locus is only ~1:2300, this previously unrecognized feature includes 863 stars from the SDSS Data Release 1. The position and shape of the feature are in good agreement with predictions of a simple binary star model that consists of a white dwarf and an M dwarf, with the components' luminosity ratio controlling the position along this binary system locus. SDSS DR1 spectra for 47 of these objects strongly support this model. The absolute magnitude--color distribution inferred for the white dwarf component is in good agreement with the models of Bergeron et al. (1995).
We investigate the stellar kinematics and stellar populations of 58
radio-loud galaxies of intermediate luminosities (L$_{3 GHz}$ $>$ 10$^{23}$ W
Hz$^{-1}$ ) at 0.6 < z < 1. This sample is ...constructed by cross-matching
galaxies from the deep VLT/VIMOS LEGA-C spectroscopic survey with the VLA 3 GHz
dataset. The LEGA-C continuum spectra reveal for the first time stellar
velocity dispersions and age indicators of z $\sim$ 1 radio galaxies. We find
that $z\sim 1$ radio-loud AGN occur exclusively in predominantly old galaxies
with high velocity dispersions: $\sigma_*>$ 175 km s$^{-1}$, corresponding to
black hole masses in excess of $10^8$ M$_{\odot}$. Furthermore, we confirm that
at a fixed stellar mass the fraction of radio-loud AGN at z $\sim$ 1 is 5 - 10
times higher than in the local universe, suggesting that quiescent, massive
galaxies at z $\sim$ 1 switch on as radio AGN on average once every Gyr. Our
results strengthen the existing evidence for a link between high black-hole
masses, radio loudness and quiescence at z $\sim$ 1.
We investigate the stellar kinematics and stellar populations of 58 radio-loud galaxies of intermediate luminosities (L\(_{3 GHz}\) \(>\) 10\(^{23}\) W Hz\(^{-1}\) ) at 0.6 < z < 1. This sample is ...constructed by cross-matching galaxies from the deep VLT/VIMOS LEGA-C spectroscopic survey with the VLA 3 GHz dataset. The LEGA-C continuum spectra reveal for the first time stellar velocity dispersions and age indicators of z \(\sim\) 1 radio galaxies. We find that \(z\sim 1\) radio-loud AGN occur exclusively in predominantly old galaxies with high velocity dispersions: \(\sigma_*>\) 175 km s\(^{-1}\), corresponding to black hole masses in excess of \(10^8\) M\(_{\odot}\). Furthermore, we confirm that at a fixed stellar mass the fraction of radio-loud AGN at z \(\sim\) 1 is 5 - 10 times higher than in the local universe, suggesting that quiescent, massive galaxies at z \(\sim\) 1 switch on as radio AGN on average once every Gyr. Our results strengthen the existing evidence for a link between high black-hole masses, radio loudness and quiescence at z \(\sim\) 1.
Poly(lactic acid) microcapsules of oxytetracycline hydrochloride were prepared by precipitation of the polymer from a solution when a non-solvent was added to a polymer solution in which the drug had ...been dispersed. Three types of microcapsules were prepared by varying the amount of drug encapsulated, as well as by using two samples of polymer with different molecular weights. The product obtained was of a matrix character consisting of agglomerated capsules. The drug release in vitro, for the best batch, was completed within 12 hours. Serum levels of the drug in rabbits treated by intramuscular injection were prolonged maximally up to 24 hours depending upon the type of microcapsules.
