Results 121 to 130 of about 8,510,179 (297)

From junk to function — How weak selection in eukaryotes builds new parts and drives genomic complexity

FEBS Letters, EarlyView.
How do genomes gain new functional parts? In eukaryotes, which tend to evolve under weak selection, much of the genome is junk. Palazzo and Qiu borrow the logic of Markov chains to show how non‐functional DNA becomes functional through the appearance of intermediate states, which arise due to epistasis, buffering, and biochemical messiness, allowing ...
Alexander F. Palazzo, Yi Qiu
wiley   +1 more source

The CARMENES search for exoplanets around M dwarfs

Astronomy & Astrophysics
Stellar rotation is closely linked to both the age and the magnetic activity of stars. Through gyrochronology, studying stellar rotation provides a means to estimate stellar ages and trace the evolution of planetary systems, and it is also a crucial ...
Varas R., Morello G., Zechmeister M., Amado P. J., Pozuelos F. J., Caballero J. A., Claret A., Cifuentes C., Morales R., Quirrenbach A., Reiners A., Ribas I., Béjar V. J. S., Cortés-Contreras M., Hatzes A. P., Henning Th., Hermelo I., Ruh H. L., Schweitzer A., Tabernero H. M., Zapatero Osorio M. R.   +20 more
doaj   +1 more source

L‐aspartate oxidase provides new insights into fumarate reduction in anaerobic darkness in Synechocystis sp. PCC6803

FEBS Letters, EarlyView.
Synechocystis strains deficient in succinate dehydrogenase (SDH) secrete more succinate than the WT under dark anaerobic conditions, supporting that SDH then primarily acts as SDH, not as a fumarate reductase. L‐aspartate oxidase (Laspo) from Synechocystis is functional under anaerobic conditions, reducing fumarate to succinate.
Kateryna Kukil, Jeffrey A. Hawkes, Cecilia Blikstad, Pia Lindberg   +3 more
wiley   +1 more source

Reassessing the low α-massive-sequence stars in Gaia DR3 spectroscopic catalogue

Astronomy & Astrophysics
Context. Studying the chemical abundance of stars of different ages and masses allows us to trace the chemical evolution of the Milky Way. Recently, a chemically depleted young, massive stellar population was identified using the spectroscopic catalogue ...
Nandakumar G., Kordopatis G., Schultheis M., Ryde N., Palicio P. A., Spitoni E., Matteucci F.   +6 more
doaj   +1 more source

A New Approach to the Long-Term Activity Behavior of DM UMa

Open Astronomy, 2012
A long-term activity character of DM UMa (K0-1 IV-III), which is one of the most active members of the RS CVn type variables, is examined using the multicolor photometric observations which spread to the time interval between 1980 and 2009. In this work,
Taş G., Evren S.
doaj   +1 more source

RNA‐related functions of BRCA2 in transcription, replication, and genome stability

FEBS Letters, EarlyView.
Beyond its role in homologous recombination, BRCA2 regulates R‐loop homeostasis, DNA–RNA hybrid resolution, RNA polymerase II dynamics, and transcriptional activation. Disruption of any of these functions can contribute to genome instability, inflammatory signaling, and tumorigenesis. BRCA2 is a central tumor suppressor protein best known for its roles
Lucia Alvaro‐Aranda, Sreerama Chaitanya Sridhara, Aura Carreira   +2 more
wiley   +1 more source

On the Possibility of an Upper Limit on Magnetically Induced Radius Inflation in Low-mass Stars

The Astrophysical Journal
The radii of low-mass stars are observed to be inflated above standard model predictions, especially in magnetically active stars. Typically, the empirical relative radius inflations Δ R / R are ≤10% but in (rare) cases may be ≥20%.
J. MacDonald, D. J. Mullan
doaj   +1 more source

Diversities and similarities exhibited by multi-planetary systems and their architectures

Astronomy & Astrophysics
The discovered planets in apparent single-planet systems (hereafter singles) and those in systems with multiple detected planets (hence-forth multis) exhibit a rich diversity of physical and orbital properties.
Muresan Alexandra, Persson Carina M., Fridlund Malcolm   +2 more
doaj   +1 more source

Artificial molecular machines and motors—Design and control of nanoscale motion

FEBS Letters, EarlyView.
Molecules are constantly moving because of thermal fluctuations, but random motion alone cannot be exploited to perform directional tasks. Artificial molecular machines use chemical, electrical, or light energy to bias this motion. Molecular shuttles, rotary motors, and supramolecular pumps illustrate how nanoscale movement can be controlled and ...
Leonardo Andreoni, Alberto Credi
wiley   +1 more source

Spectroscopic survey of Kepler stars – II. FIES/NOT observations of A- and F-type stars

, 2017
We have analysed high-resolution spectra of 28 A and 22 F stars in the Kepler field, observed using the Fibre-Fed Échelle Spectrograph at the Nordic Optical Telescope. We provide spectral types, atmospheric parameters and chemical abundances for 50 stars.
S. J. Murphy, J. M. Lykke, G. Michalska, M. Polińska, Lykke, Julie Maria, B. Smalley, Triviño Hage, A., A. Triviño Hage, Smalley, B., E. Niemczura, K. Uytterhoeven, Uytterhoeven, K., Michalska, G., Polińska, M., J. Jessen-Hansen, Kołaczkowski, Z., Kolaczkowski, Z., Jessen-Hansen, J., Z. Kołaczkowski, Niemczura, E., Murphy, S. J., Lykke, J. M.   +21 more
core   +1 more source