Results 21 to 30 of about 114,632 (282)

Meta-analysis of Photometric and Asteroseismic Measurements of Stellar Rotation Periods: The Lomb–Scargle Periodogram, Autocorrelation Function, and Wavelet and Rotational Splitting Analysis for 92 Kepler Asteroseismic Targets

The Astrophysical Journal, 2022
We perform intensity variability analyses (photometric analyses: the Lomb–Scargle periodogram, autocorrelation, and wavelet) and asteroseismic analysis of 92 Kepler solar-like main-sequence stars to understand the reliability of the measured stellar ...
Yuting Lu, Othman Benomar, Shoya Kamiaka, Yasushi Suto   +3 more
doaj   +1 more source

Learning about the latitudinal distribution of starspots through the periodogram analysis of photometric data

EPJ Web of Conferences, 2017
Starspots are cooler and darker than the stellar surface. Therefore, the emitted flux of a star changes when spots are visible on its surface. The presence of spots together with the stellar rotation leads to a periodic modulation on the light curve.
Santos Ângela R. G., Cunha Margarida S., Avelino Pedro P., García Rafael A., Mathur Savita   +4 more
doaj   +1 more source

Polar branches of stellar activity waves: dynamo models and observations

, 2011
[Abridged abstract:] Stellar activity data provide evidence of activity wave branches propagating polewards rather than equatorwards (the solar case). Stellar dynamo theory allows polewards propagating dynamo waves for certain governing parameters.
A. F. Lanza, Baliunas, Baliunas, Barnes, Berdyugina, Brandenburg, Brandenburg, Brandenburg, Brandenburg, Brandenburg, Charbonneau, Choudhuri, Courvoisier, Covas, D. Moss, D. Sokoloff, Dikpati, Dikpati, Dikpati, Donahue, Durney, Granzer, Hall, Holzwarth, Işik, Jeffers, Jouve, Järvinen, Katsova, Kleeorin, Kovári, Käpylä, Lanza, Lanza, Mackay, Makarov, Messina, Moss, Moss, Moss, Moss, Moss, Noyes, Noyes, Oláh, Ossendrijver, Rüdiger, Rüdiger, Rüdiger, Schmitt, Schrijver, Strassmeier, Subramanian, Tobias, Vogt, Wilmot-Smith, Zhang   +56 more
core   +1 more source

The Resolved Structure and Dynamics of an Isolated Dwarf Galaxy: A VLT and Keck Spectroscopic Survey of WLM [PDF]

, 2012
We present spectroscopic data for 180 red giant branch stars in the isolated dwarf irregular galaxy WLM. Observations of the Calcium II triplet lines in spectra of RGB stars covering the entire galaxy were obtained with FORS2 at the VLT and DEIMOS on ...
Abadi, Alan W. McConnachie, Alyson M. Brooks, Andrew A. Cole, Appenzeller, Bender, Bigiel, Bolatto, Bovill, Bresolin, Brooks, Brooks, Demarque, Dolphin, Eline Tolstoy, Fuchs, Gallouet, Geha, Geha, Giuseppina Battaglia, Gnedin, Górski, Hargreaves, Hidalgo, Hill, Hinz, Hodge, Hunter, Ibata, Irwin, J. Trevor Mendel, Jackson, Jackson, Karachentsev, Kazantzidis, Kepley, Kim A. Venn, Krumholz, Kuhlen, Lacey, Leaman, Leaman, Lee, Leroy, Lynden-Bell, Madau, Markwardt, Martínez-Delgado, Mayer, Mayer, Melotte, Mike J. Irwin, Mo, Moore, Navarro, Peñarrubia, Plummer, Pritzl, Ricotti, Robertson, Robertson, Rodrigo A. Ibata, Ryan Leaman, Schruba, Sellwood, Seth, Skillman, Tatton, Tolstoy, Urbaneja, van der Marel, van der Marel, Venn, Venn, Walker, Walker, Whiting, Yoachim, Łokas   +78 more
core   +2 more sources

Rad27/FEN1 prevents accumulation of Okazaki fragments and ribosomal DNA copy number changes

FEBS Letters, EarlyView.
The budding yeast Rad27 is a structure‐specific endonuclease. Here, the authors reveal that Rad27 is crucial for maintaining the stability of the ribosomal RNA gene (rDNA) region. Rad27 deficiency leads to the accumulation of Okazaki fragments and changes in rDNA copy number.
Tsugumi Yamaji, Yuko Katayama, Nanase Arata, Mariko Sasaki   +3 more
wiley   +1 more source

Asteroseismology and Spectropolarimetry of the Exoplanet Host Star λ Serpentis

The Astronomical Journal, 2023
The bright star λ Ser hosts a hot Neptune with a minimum mass of 13.6 M _⊕ and a 15.5 day orbit. It also appears to be a solar analog, with a mean rotation period of 25.8 days and surface differential rotation very similar to the Sun.
Travis S. Metcalfe, Derek Buzasi, Daniel Huber, Marc H. Pinsonneault, Jennifer L. van Saders, Thomas R. Ayres, Sarbani Basu, Jeremy J. Drake, Ricky Egeland, Oleg Kochukhov, Pascal Petit, Steven H. Saar, Victor See, Keivan G. Stassun, Yaguang Li, Timothy R. Bedding, Sylvain N. Breton, Adam J. Finley, Rafael A. García, Hans Kjeldsen, Martin B. Nielsen, J. M. Joel Ong, Jakob L. Rørsted, Amalie Stokholm, Mark L. Winther, Catherine A. Clark, Diego Godoy-Rivera, Ilya V. Ilyin, Klaus G. Strassmeier, Sandra V. Jeffers, Stephen C. Marsden, Aline A. Vidotto, Sallie Baliunas, Willie Soon   +33 more
doaj   +1 more source

Investigating variation of latitudinal stellar spot rotation and its relation to the real stellar surface rotation

, 2011
In this work the latitude dependent stellar spot rotation is investigated based on dynamo models. The maps of the magnetic pressure at the surface from the dynamo calculations are treated similarly to the temperature maps obtained using Doppler imaging ...
Elstner, D., Korhonen, H.
core   +1 more source

The first observed stellar occultations by the irregular satellite Phoebe (Saturn IX) and improved rotational period [PDF]

, 2019
peer reviewedWe report six stellar occultations by Phoebe (Saturn IX), an irregular satellite of Saturn, obtained between mid-2017 and mid-2019. The 2017 July 6 event was the first stellar occultation by an irregular satellite ever observed.
Assafin, Marcelo, Barry, T., Benedetti-Rossi, Gustavo, Braga-Ribas, Felipe, Camargo, J. I. B., Campbell-White, J., De Horta, A., Desmars, Josselin, Fernández-Lajús, E., Giles, D., Gomes-Júnior, A. Ramos, Hanna, W., Hayamizu, T., Hirose, T., Horvat, R., Hosoi, K., Jehin, Emmanuel, Kerr, S., Machado, D. I., Mammana, L. A., Maybour, D., Morgado, Bruno Eduardo, Owada, M., Rahvar, S., Sicardy, B., Snodgrass, C., Vieira-Martins, R.   +26 more
core   +5 more sources

Targeting EZH2 reverses thyroid cell dedifferentiation and enhances iodide uptake in anaplastic thyroid cancer

FEBS Letters, EarlyView.
Anaplastic thyroid cancer (ATC) lacks iodide uptake ability due to MAPK activation increasing the expression of the histone methyltransferase EZH2, which represses thyroid differentiation genes (TDGs) such as the sodium iodide symporter (NIS). Dual inhibition of MAPK (U0126) and EZH2 (EPZ6438/Tazemetostat) reverses this mechanism, thus restoring TDG ...
Diego Claro de Mello, Marcella Maringolo Cristovão, Guilherme Henrique, Vinicius Gonçalves Rodrigues, Caroline Serrano‐Nascimento, Edna Teruko Kimura, Cesar Seigi Fuziwara   +6 more
wiley   +1 more source

The Evolution of Stellar X-Ray Activity and Angular Momentum as Seen by eROSITA, TESS, and Gaia

The Astrophysical Journal Letters
We have assembled a sample of ∼8200 stars with spectral types F5V–M5V, all having directly measured X-ray luminosities from eROSITA and rotation periods from TESS and having empirically estimated ages via their membership in stellar clusters and groups ...
Keivan G. Stassun, Marina Kounkel
doaj   +1 more source