Results 61 to 70 of about 167,710 (319)

Origin of α-poor Very Metal-poor Stars

The Astrophysical Journal
Among very metal-poor (VMP) stars, α -poor VMP ( α -PVMP) stars that have subsolar values of [X/Fe] for Mg and other α elements are rare and are thought to have been formed from gas polluted by Type 1a supernova (SN 1a). However, recent analyses indicate
S. K. Jeena, Projjwal Banerjee
doaj   +1 more source

Chemical constraints on the formation of the Galactic thick disk

EPJ Web of Conferences, 2012
We highlight some results from our detailed abundance analysis study of 703 kinematically selected F and G dwarf stars in the solar neighbourhood. The analysis is based on spectra of high-resolution (R = 45000 to 110 000) and high signal-to-noise (S/N ...
Feltzing S., Bensby T.
doaj   +1 more source

The Gaia-ESO Survey: the most metal-poor stars in the Galactic bulge

, 2014
We present the first results of the EMBLA survey (Extremely Metal-poor BuLge stars with AAOmega), aimed at finding metal-poor stars in the Milky Way bulge, where the oldest stars should now preferentially reside.
Asplund, M., Bensby, T., Bergemann, M., Bessell, M. S., Casagrande, L., Casey, A. R., Costado, M. T., Da Costa, G. S., Damiani, F., de Laverny, P., Feltzing, S., Flaccomio, E., Gilmore, G., Heiter, U., Hill, V., Hourihane, A., Howes, L., Jofré, P., Keller, S. C., Korn, A. J., Lardo, C., Lind, K., Magrini, L., Maiorca, E., Marino, A. F., Masseron, T., Minniti, D., Morbidelli, L., Nataf, D. M., Owen, C. I., Pancino, E., Prieto, C. Allende, Randich, S., Recio-Blanco, A., Sacco, G. G., Schmidt, B. P., Smiljanic, R., Tisserand, P., Vallenari, A., Worley, C., Yong, D., Zoccali, M.   +41 more
core   +1 more source

An Elemental Assay of Very, Extremely, and Ultra Metal-Poor Stars [PDF]

, 2015
We present a high-resolution elemental-abundance analysis for a sample of 23 very metal-poor (VMP; [Fe/H] < -2.0) stars, 12 of which are extremely metal-poor (EMP; [Fe/H] < -3.0), and 4 of which are ultra metal-poor (UMP; [Fe/H] < -4.0). These stars were
Asplund, M., Beers, T. C., Bessell, M. S., Christlieb, N., Frebel, A., Hansen, C. J., Hansen, T., Norris, J. E., Perez, A. E. Garcia, Placco, V. M., Yong, D.   +10 more
core   +2 more sources

CNO Abundances in Metal-Poor Stars [PDF]

Proceedings of 11th Symposium on Nuclei in the Cosmos — PoS(NIC XI), 2011
Carbon, nitrogen, and oxygen produced in the early universe come from a variety of possible astrophysical sites. Among these are early supernovae, winds of massive, rapidly-rotating, mega metal-poor stars, and intermediate mass AGB stars. Large-scale surveys such as the HK Survey of Beers and colleagues and the Hamburg/ESO Survey of Christlieb and ...
Catherine Kennedy, Timothy Beers, Birgitta Nordstrom, Vinicius Placco, Silvia Rossi, Thirupathi Sivarani   +5 more
openaire   +1 more source

Peroxidasin enables melanoma immune escape by inhibiting natural killer cell cytotoxicity

Molecular Oncology, EarlyView.
Peroxidasin (PXDN) is secreted by melanoma cells and binds the NK cell receptor NKG2D, thereby suppressing NK cell activation and cytotoxicity. PXDN depletion restores NKG2D signaling and enables effective NK cell–mediated melanoma killing. These findings identify PXDN as a previously unrecognized immune evasion factor and a potential target to improve
Hsu‐Min Sung, David Bickel, Lena C. M. Krause, Daria Ezeriņa, Christian Ickes, Julian Wojtachnia, Christine S. Gibhardt, Magdalena Shumanska, Khadija Wahni, Andrea Paluschkiwitz, Julia Malo Pueyo, Ekaterina Baranova, Wim Vranken, Hedwig Stanisz, Ioana Stejerean‐Todoran, Michael P. Schön, Joris Messens, Ivan Bogeski   +17 more
wiley   +1 more source

Investigating the Lower Limit of Metallicity for the Galactic Thin Disk

The Astrophysical Journal
We explore the metal-poor regime of the Galactic disk on the distribution of stars in the [ α /M]– V _ϕ plane, to identify the most metal-poor thin disk (MPTnD) stars belonging to the low- α sequence.
Guozhen Hu, Zhengyi Shao, Erbil Gügercinoǧlu, Wenyuan Cui   +3 more
doaj   +1 more source

Feasibility and Tolerability of Performing Portable MRI for Neurological Disorders in an Outpatient Neurology Clinic: A Prospective Cohort

Annals of Clinical and Translational Neurology, EarlyView.
ABSTRACT Background Accessing brain magnetic resonance imaging (MRI) can be challenging, especially for underserved patients, which may lead to disparities in neurological diagnosis. Method This mixed‐methods study enrolled adults with one of four neurological disorders: mild cognitive impairment or dementia of the Alzheimer type, multiple sclerosis ...
Maya L. Mastick, Nomin Enkhtsetseg, Joseph Sadok, Matheus Mochetti, Annabel Sorby Adams, Jennifer Guo, Cristina Trapaga Hacker, Isabella Gomez Hjerthen, Seungwon Lee, Siddharth Satish, Andrew S. Ham, Justin Hill, Denis Balaban, Kevin Kyle, Rebecca L. Gillani, Marcelo Matiello, Aleksandar Videnovic, Eric C. Klawiter, W. Taylor Kimberly, Farrah J. Mateen   +19 more
wiley   +1 more source

A Catalog of 12,766 Carbon-enhanced Metal-poor Stars from LAMOST Data Release 8

The Astrophysical Journal Supplement Series
Metal-poor stars are a rare and ancient type of star; carbon-enhanced metal-poor (CEMP) stars are a subset of these celestial bodies that show an enrichment of carbon relative to iron.
Ziyu Fang, Xiangru Li, Haining Li
doaj   +1 more source

Beyond Spectroscopy. II. Stellar Parameters for over 20 Million Stars in the Northern Sky from SAGES DR1 and Gaia DR3

The Astrophysical Journal, 2023
We present precise photometric estimates of stellar parameters, including effective temperature, metallicity, luminosity classification, distance, and stellar age, for nearly 26 million stars using the methodology developed in the first paper of this ...
Yang Huang, Timothy C. Beers, Haibo Yuan, Ke-Feng Tan, Wei Wang, Jie Zheng, Chun Li, Young Sun Lee, Hai-Ning Li, Jing-Kun Zhao, Xiang-Xiang Xue, Yujuan Liu, Huawei Zhang, Xue-Ang Sun, Ji Li, Hong-Rui Gu, Christian Wolf, Christopher A. Onken, Jifeng Liu, Zhou Fan, Gang Zhao   +20 more
doaj   +1 more source