Results 51 to 60 of about 167,710 (319)

The Frequency of Carbon Stars among Extremely Metal-poor Stars [PDF]

The Astrophysical Journal, 2005
We demonstrate that there are systematic scale errors in the [Fe/H] values determined by the Hamburg/ESO Survey (and by inference by the HK Survey in the past) for certain extremely metal poor highly C-enhanced giants. The consequences of these scale errors are that a) the fraction of carbon stars at extremely low metallicities has been overestimated ...
Cohen, Judith G., Shectman, Stephen, Thompson, Ian, McWilliam, Andrew, Christlieb, Norbert, Meléndez, Jorge, Zickgraf, Franz-Josef, Ramírez, Solange, Swenson, Amber   +8 more
openaire   +3 more sources

The R-Process Alliance: Chemodynamically Tagged Groups. II. An Extended Sample of Halo r-process-enhanced Stars

The Astrophysical Journal, 2023
Orbital characteristics based on Gaia Early Data Release 3 astrometric parameters are analyzed for ∼1700 r -process-enhanced (RPE; [Eu/Fe] > +0.3) metal-poor stars ([Fe/H] ≤ −0.8) compiled from the R -Process Alliance, the GALactic Archaeology with ...
Derek Shank, Timothy C. Beers, Vinicius M. Placco, Dmitrii Gudin, Thomas Catapano, Erika M. Holmbeck, Rana Ezzeddine, Ian U. Roederer, Charli M. Sakari, Anna Frebel, Terese T. Hansen   +10 more
doaj   +1 more source

THE MOST METAL-POOR STARS. II. CHEMICAL ABUNDANCES OF 190 METAL-POOR STARS INCLUDING 10 NEW STARS WITH [Fe/H] ⩽ –3.5, , [PDF]

The Astrophysical Journal, 2012
We present a homogeneous chemical abundance analysis of 16 elements in 190 metal-poor Galactic halo stars (38 program and 152 literature objects). The sample includes 171 stars with [Fe/H] < -2.5, of which 86 are extremely metal poor, [Fe/H] < -3.0. Our program stars include ten new objects with [Fe/H] < -3.5.
Yong, David, Norris, John, Bessell, Michael, Christlieb, N, Asplund, Martin, Beers, Timothy C, Barklem, Paul S, Frebel, Anna, Ryan, S. G.   +8 more
openaire   +5 more sources

An abundance study of red-giant-branch stars in the Hercules dwarf spheroidal galaxy [PDF]

, 2010
Using high-resolution spectroscopy, we provide a determination of [Fe/H] and [Ca/H] for confirmed red-giant branch member stars of the Hercules dwarf spheroidal galaxy.
A. Koch, Adén, Adén, Alonso, Andrievsky, Aoki, Asplund, Belokurov, Bensby, Burris, Calamida, Calamida, Clem, Cohen, D. Adén, Dotter, E. K. Grebel, Edvardsson, Feltzing, Frebel, Frebel, Fulbright, Fulbright, Geisler, Gilmore, Gratton, Gratton, Gratton, Grebel, Grevesse, Gustafsson, Hanson, Helmi, Ivans, Ivans, Johnson, K. Eriksson, Kirby, Kirby, Kirby, Koch, Koch, Koch, Koch, Kupka, Kupka, Lind, M. I. Wilkinson, Martin, Matteucci, McWilliam, McWilliam, McWilliam, Nissen, Norris, Pasquini, Piskunov, Prochaska, Reddy, Ryabchikova, Ryan, S. Feltzing, Sadakane, Schlegel, Schörck, Shetrone, Shetrone, Simon, Simon, Starkenburg, Stephens, Tollerud, Tolstoy, VandenBerg, Venn, Walker, Woosley, Zucker   +77 more
core   +1 more source

SIRIUS: Identifying Metal-poor Stars Enriched by a Single Supernova in a Dwarf Galaxy Cosmological Zoom-in Simulation Resolving Individual Massive Stars

The Astrophysical Journal Letters
Metal-poor stars enriched by a single supernova (mono-enriched stars) are direct proof (and provide valuable probes) of supernova nucleosynthesis. Photometric and spectroscopic observations have shown that metal-poor stars have a wide variety of chemical
Yutaka Hirai, Takayuki R. Saitoh, Michiko S. Fujii, Katsuhiro Kaneko, Timothy C. Beers   +4 more
doaj   +1 more source

Searching for metal-poor stars

, 2023
International audience ; Metal-poor stars are fundamental objects to understand the formation and the chemical evolution of the Milky Way. They hold in their atmospheres the fossil record of the chemical composition of the early phases of the Universe so that their chemical analysis provides important constraints on the masses of the first stellar ...
openaire   +1 more source

Protein pyrophosphorylation by inositol pyrophosphates — detection, function, and regulation

FEBS Letters, EarlyView.
Protein pyrophosphorylation is an unusual signaling mechanism that was discovered two decades ago. It can be driven by inositol pyrophosphate messengers and influences various cellular processes. Herein, we summarize the research progress and challenges of this field, covering pathways found to be regulated by this posttranslational modification as ...
Sarah Lampe, Tanmay Kumar Mohanty, Rashna Bhandari, Dorothea Fiedler   +3 more
wiley   +1 more source

Early r-process Enrichment and Hierarchical Assembly Across the Sagittarius Dwarf Galaxy

The Astronomical Journal
Dwarf galaxies like Sagittarius (Sgr) provide a unique window into the early stages of galactic chemical evolution, particularly through their metal-poor stars.
Xiaowei Ou, Alexander Yelland, Anirudh Chiti, Anna Frebel, Guilherme Limberg, Mohammad K. Mardini   +5 more
doaj   +1 more source

Scandium Abundance in Metal-poor Stars [PDF]

Proceedings of the International Astronomical Union, 2013
AbstractThe Scandium abundances for 85 metal-poor stars are presented. Our result shows that NLTE corrections for Sc II lines are small (−0.04 to +0.06 dex). The abundance trends in stars of different populations are discussed.
H. W. Zhang, T. Gehren, G. Zhao
openaire   +1 more source

Plecstatin inhibits hepatocellular carcinoma tumorigenesis and invasion through cytolinker plectin

Molecular Oncology, EarlyView.
The ruthenium‐based metallodrug plecstatin exerts its anticancer effect in hepatocellular carcinoma (HCC) primarily through selective targeting of plectin. By disrupting plectin‐mediated cytoskeletal organization, plecstatin inhibits anchorage‐dependent growth, cell polarization, and tumor cell dissemination.
Zuzana Outla, Jan Kosla, Magdalena Prechova, Lukas Frick, Patricia Bortel, Yasmin Borutzki, Andrea Bileck, Christopher Gerner, Samuel M. Meier‐Menches, Selma Osmanagic‐Myers, Martin Gregor   +10 more
wiley   +1 more source