Results 101 to 110 of about 3,156,581 (329)

Discovery of SiC and Iron Dust around AGB Stars in the Very Metal-poor Sextans a Dwarf Galaxy with JWST: Implications for Dust Production at High Redshift

The Astrophysical Journal
Low-resolution infrared spectroscopy from JWST confirms the presence of SiC and likely metallic iron dust around asymptotic giant branch (AGB) stars in the Sextans A dwarf galaxy, which has a metallicity ∼1%–7% Z _⊙ .
M. L. Boyer, G. C. Sloan, A. Nanni, E. Tarantino, I. McDonald, S. Goldman, J. A. D. L. Blommaert, F. Dell’Agli, M. Di Criscienzo, D. A. García-Hernández, Robert D. Gehrz, M. A. T. Groenewegen, A. Javadi, O. C. Jones, F. Kemper, M. Marengo, Kristen B. W. McQuinn, Joana M. Oliveira, Giada Pastorelli, Julia Roman-Duval, R. Sahai, Evan D. Skillman, S. Srinivasan, J. Th. van Loon, Daniel R. Weisz, Patricia A. Whitelock   +25 more
doaj   +1 more source

On the Spectrum of Extremely Metal-Poor Star HD 52961

Open Astronomy, 2013
High resolution spectra of the extremely metal-poor star HD 52961 are investigated. The atmospheric parameters found are: Teff = 6000 ± 100 K, log g = 0.5±0.5, ξt = 6.8 km s−1, [Fe/H] = −4.50±0.20. The carbon abundance is close to the solar one, [C/H] = −
Kipper Tõnu
doaj   +1 more source

ON EVOLUTIONARY STATUS OF STARS WITH THE R CrB PHENOMENON

Odessa Astronomical Publications, 2017
Two key features are important for understanding the evolution of stars with the R Coronae Borealis variability: the state of high mass loss rate and the carbon overabundance. The hydrogen deficiency is a consequence of these two characteristics.
A. E. Rosenbush
doaj   +1 more source

High resolution optical spectroscopy of IRAS 09425-6040 (=GLMP 260)

, 2006
We present high resolution optical spectroscopic observations of IRAS 09425-6040, a peculiar, extremely red, C-rich AGB star showing prominent O-rich dust features in its ISO infrared spectrum attributed to crystalline silicates.
A. Manchado, Abia, Abia, Abia, Barbuy, Blöcker, C. Abia, Cameron, Cayrel, Chan, D. A. García-Hernández, Deupree, Domínguez, Eriksson, Forestini, Fouque, Frost, García-Lario, Jorissen, Kwok, Lambert, Lorenz-Martins, Mazzitelli, Molster, Ohnaka, P. García-Lario, Querci, Rubén, Sackmann, Sylvester, Thévenin, Wasserburg, Waters, Yang, Zijlstra   +34 more
core   +1 more source

Cis‐unsaturated sphingolipids support growth of sphingoid base‐deficient yeast but impair plasma membrane integrity

FEBS Open Bio, EarlyView.
Sphingoid base structures, the sphingolipid backbones, vary among species. We established yeast cells in which the native sphingoid base was replaced with plant‐type bases containing cis or trans double bonds. This is, to our knowledge, the first eukaryotic model mostly composed of sphingolipids containing cis‐unsaturated sphingoid base, providing a ...
Takashi Higuchi, Saki Sugihara, Yohei Ishibashi, Kono Yushi, Hazuki Yamauchi, Motohiro Tani   +5 more
wiley   +1 more source

The CIViL* Survey: The Discovery of a C iv Dichotomy in the Circumgalactic Medium of L* Galaxies

The Astrophysical Journal Letters
This paper investigates C iv absorption in the circumgalactic medium (CGM) of L ^⋆ galaxies and its relationship with galaxy star formation rates. We present new observations from the C iv in L ^⋆ galaxies survey (PID # 17076) using the Hubble Space ...
Samantha L. Garza, Jessica K. Werk, Trystyn A. M. Berg, Yakov Faerman, Benjamin D. Oppenheimer, Rongmon Bordoloi, Sara L. Ellison   +6 more
doaj   +1 more source

Electrical pulse stimulation reflecting the episodic nature of real‐life exercise modulates metabolic and secretory profile of primary human myotubes

FEBS Open Bio, EarlyView.
Here, we introduced an intermittent electrical stimulation protocol mimicking the episodic nature of real‐life exercise in vitro by alternating low‐ and high‐frequency stimulation. In comparison with widely used continuous stimulation, it enhanced the rate of glucose and fatty acid oxidation, but not the myokine release.
Klára Gabrišová, Tímea Kurdiová, Daria Barkova, Natália Pálešová, Jana Babulicová, Silvia Tyčiaková, Marta Novotová, Mária Balážová, Miroslav Sabo, Václav Pustka, Jozef Ukropec, Barbara Ukropcová   +11 more
wiley   +1 more source

Third Dredge-up in Low Mass Stars: Solving the LMC Carbon Star Mystery

, 2004
A long standing problem with asymptotic giant branch (AGB) star models has been their inability to produce the low-luminosity carbon stars in the Large and Small Magellanic Clouds. Dredge-up must begin earlier and extend deeper.
Böhm-Vitense, Christopher A. Tout, Cook, Eggleton, Frost, Groenewegen, Harries, Herwig, Iben, Iben, Izzard, Izzard, Karakas, Kroupa, Marigo, Mowlavi, Pols, Pols, Richard J. Stancliffe, Robert G. Izzard, Sackmann, Stancliffe, Straniero, Van Eck, Vassiliadis, Wood, Wood   +26 more
core   +2 more sources

Berberine–cinnamic acid co‐crystal effect in ameliorating hyperlipidemia might be regulated through the PI3K/AKT/mTOR/SREBP‐1 signaling pathway

FEBS Open Bio, EarlyView.
Berberine–cinnamic acid co‐crystal (BBR‐CA) inhibits the phosphorylation of the phosphatidylinositol 3‐kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) pathway, suppressing the transfer of pre‐sterol regulatory element‐binding proteins‐1 (SREBP‐1) from the endoplasmic reticulum to the nucleus. This results in a decrease in the expression level of
Wenheng Gao, Yunlong Li, Lihua Chen, Wenshuo Yang, Yong He, Ye Yang, Dengke Yin, Song Tan   +7 more
wiley   +1 more source

Hydrodynamic simulations of shell convection in stellar cores

, 2011
Shell convection driven by nuclear burning in a stellar core is a common hydrodynamic event in the evolution of many types of stars. We encounter and simulate this convection (i) in the helium core of a low-mass red giant during core helium flash leading
A Chieffi, A Weiss, CA Meakin, CA Meakin, F Herwig, HJS Fernando, J Montalbán, L Siess, L Siess, M Mocák, M Mocák, N Iwamoto, NH Brummell, S Cassisi, SW Campbell, TM Brown   +15 more
core   +1 more source