Results 61 to 70 of about 199,190 (345)

Comparing Be Star Inclination Angles Determined from Hα Fitting and Gravitational Darkening

The Astrophysical Journal, 2023
Using a sample of 92 Galactic Be stars, we compare inclination angles (the angle between a star’s rotation axis and the line of sight) determined from H α emission-line profile fitting to those determined by the spectroscopic signature of gravitational ...
T. A. A. Sigut, Nastaran R. Ghafourian
doaj   +1 more source

HdBe stars: hydrogen-deficient supergiants with emission lines [PDF]

Symposium - International Astronomical Union, 1994
The hydrogen-deficient B stars (often known as extreme-helium stars: EHes) show weak or absent Balmer lines and the following properties (Heber 1986a): Teff ~ 12 − 25kK, log g ~ 2 − 3, log nH ~ −3 − −4, nHe ≈ 0.99, nC ~ 0.01. Their galactic positions and apparent magnitudes indicate that they are low-mass supergiants belonging to the Galactic bulge ...
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

First JWST/NIRSpec Spectroscopy of O Stars in the Small Magellanic Cloud

The Astrophysical Journal Letters
Determining how much mass is removed by stellar winds is crucial to understanding massive star evolution and feedback. However, traditional spectroscopic diagnostics in the UV and optical are not sensitive enough to characterize weak stellar winds of OB ...
Armin Mang Román, Peter Zeidler, Wolf-Rainer Hamann, Lidia M. Oskinova, M. J. Rickard, S. Reyero Serantes, H. Todt, J. S. Gallagher III, D. Massa, D. Pauli, V. Ramachandran, E. Sabbi, A. A. C. Sander   +12 more
doaj   +1 more source

Exploring the Variability of Three Be Stars with TESS Observations

Universe
Be stars are rapidly rotating B-type stars surrounded by circumstellar disks formed from self-ejected material. Understanding the mechanisms driving mass ejection and disk formation, known as the Be phenomenon, requires a detailed investigation of their ...
Laerte Andrade, Alan W. Pereira, Marcelo Emilio, Eduardo Janot-Pacheco   +3 more
doaj   +1 more source

Optical Spectroscopy of the Surface Population of the rho Ophiuchi Molecular Cloud: The First Wave of Star Formation

, 2005
We present the results of optical spectroscopy of 139 stars obtained with the Hydra multi-object spectrograph. The objects extend over a 1.3 square degree area surrounding the main cloud of the rho Oph complex.
Alcala J. M., Baraffe I., Bertelli G., Bouvier J., Bruce A. Wilking, Chini R., de Geus E. J., Dolidze M. V., D’Antona F., Festin L., Grosso N., John G. Robinson, Michael R. Meyer, Sterzik M. F., Thomas P. Greene   +14 more
core   +1 more source

Dammarenediol II enhances etoposide‐induced apoptosis by targeting O‐GlcNAc transferase and Akt/GSK3β/mTOR signaling in liver cancer

Molecular Oncology, EarlyView.
Etoposide induces DNA damage, activating p53‐dependent apoptosis via caspase‐3/7, which cleaves PARP1. Dammarenediol II enhances this apoptotic pathway by suppressing O‐GlcNAc transferase activity, further decreasing O‐GlcNAcylation. The reduction in O‐GlcNAc levels boosts p53‐driven apoptosis and influences the Akt/GSK3β/mTOR signaling pathway ...
Jaehoon Lee, Byung‐Cheol Han, Gi‐Bang Koo, Jihye Park, Mijin Kwon, Young Bin Park, Jae‐Mun Choi, Seung‐Ho Lee, Sangho Roh   +8 more
wiley   +1 more source

Strong Variable Ultraviolet Emission from Y Gem: Accretion Activity in an AGB Star with a Binary Companion? [PDF]

, 2011
Binarity is believed to dramatically affect the history and geometry of mass loss in AGB and post-AGB stars, but observational evidence of binarity is sorely lacking.
Alcolea, Bodenheimer, Bond, Calvet, Gullbring, Hrivnak, Jeffries, Jura, Kahane, Karovska, Kastner, Loup, Mastrodemos, Morrissey, Querci, Robinson, Sahai, Sahai, Sahai, Sahai, Schwarz, Soker, Soker, Soker, Van Winckel, Welsh, Wood   +26 more
core   +3 more sources

The PI3Kδ inhibitor roginolisib (IOA‐244) preserves T‐cell function and activity

Molecular Oncology, EarlyView.
Identification of novel PI3K inhibitors with limited immune‐related adverse effects is highly sought after. We found that roginolisib and idelalisib inhibit chronic lymphocytic leukemia (CLL) cells and Treg suppressive functions to similar extents, but roginolisib affects cytotoxic T‐cell function and promotion of pro‐inflammatory T helper subsets to a
Elise Solli, Alessio Bevilacqua, Mathias Wenes, Denis Migliorini, Lars van der Veen, Sigrid S Skånland, Giusy Di Conza, Kjetil Taskén   +7 more
wiley   +1 more source

A Model of the C iv λ λ1548, 1550 Doublet Line in T Tauri Stars

The Astrophysical Journal
The C iv doublet in the UV has long been associated with accretion in T Tauri stars. However, it is still unclear where and how the lines are formed. Here, we present a new C iv line model based on the currently available accretion shock and accretion ...
Thanawuth Thanathibodee, Connor E. Robinson, Nuria Calvet, Catherine C. Espaillat, Caeley V. Pittman, Nicole Arulanantham, Kevin France, Hans Moritz Günther, Seok-Jun Chang, P. Christian Schneider   +9 more
doaj   +1 more source