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OBJECTIVE People who live in poverty have a high prevalence of smoking, are less likely to engage in evidence-based treatment, and find it harder to quit. Their beliefs about smoking and quitting can serve as barriers to quitting. Little is known about the smoking and quitting beliefs of the very poor (about U.S. $15,000 or less annual family income) because they tend not to be included in rese...
We report on a attempt to detect beryllium in two dwarf stars of the Galactic halo with metallicities below one thousandth solar. The data were obtained during the Commissioning of the Ultraviolet and Visible Echelle Spectrograph (UVES) mounted on the ESO VLT Kueyen telescope, and show the potential of UVES for studies in the UV-optical domain. We claim a beryllium detection in LP 815–43 ([Fe/H...
We study the age and metallicity distribution function (MDF) of metal-poor stars in the Milky Way halo as a function of galactocentric radius by combining N-body simulations and semi-analytical methods. We find that the oldest stars populate the innermost region, while extremely metal-poor stars are more concentrated within r < 60 kpc. We predict that the MDF of [Fe/H]≤ −2 stars varies only ver...
The Goddard High Resolution Spectrograph (GHRS) of the Hubble Space Telescope (HST) has been used to observe the boron 2500 Å region of BD −13 3442. At a metallicity of [Fe/H]=−3.00 this is the most metal-poor star ever observed for B. Nearly 26 hours of exposure time resulted in a detection. Spectrum synthesis using the latest Kurucz model atmospheres yields an LTE boron abundance of log (B)= ...
A search for lithium is performed on seven metal poor dwarfs with metallicities ranging from [Fe/H]=-1.5 down to [Fe/H]=-3.0 but showing disk–like kinematics. These stars belong to the metal poor tail of the Galactic thick disk and they may be also the result of an accretion event (Beers and Sommer-Larsen 1995). The Li 6707.8 Å line is present in all the seven dwarfs. The weighted average of th...
BACKGROUND Malnutrition is prevalent in elderly populations. Recommended methods of nutritional screening are often too complicated and time-consuming for routine application in frail, very old, hospitalized patients. OBJECTIVE Our aims were to identify risk factors for development of malnutrition in very old hospitalized patients and to evaluate the total Mini Nutritional Assessment (MNA) sc...
Europium isotopic abundance fractions are reported for the very metal-poor, neutron-capture-rich giant stars CS 22892-052, HD 115444, and BD +17◦3248. The abundance fractions, derived from analysis of several strong Eu II lines appearing in high-resolution spectra of these stars, are in excellent agreement with each other and with their values in the Solar System: fr(Eu)≃ fr(Eu) ≃ 0.5. Detailed...
I report on recent results from observations of stars with metallicities [Fe/H] ≤ −2.0. These include a substantial new sample of objects with high-resolution observations obtained as part of a follow-up of the HK Survey, The Hamburg/ESO Survey, and the ongoing survey SEGUE: Sloan Extension for Galactic Understanding and Exploration. Perspectives on the next directions are also provided.
Wediscuss some consequences for the determination of the surface gravity parameter of very metal-poor halo dwarfs in the new light shed upon these objects from the Hipparcos astrometry. Whereas it has become clear that standard spectroscopic LTE iron ionization equilibria are prone to systematic errors, in the sense, that stages of evolution are predicted that are actually not yet reached, the ...
1 Max Plack Institute for Astrophysics, Karl-Schwarzschild-Strasse 1, 857 41 Garching bei München, Germany 2 Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA, United Kingdom e-mail: [email protected] 3 Departamento de Astronomia do IAG/USP, Universidade de São Paulo, Rua do Matão 1226, Cidade Universitària, 05508-900 São Paulo, SP, Brazil 4 Research School o...
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