Results 111 to 120 of about 992,258 (306)

Abundance of Helium in Stellar Atmospheres [PDF]

Highlights of Astronomy, 1971
Helium abundance in stellar atmospheres has been the subject of several recent investigations, essentially induced by progresses in the computation of non-grey model atmospheres (including line blanketing in the far U.V.), by considerable advances in the theory of Stark broadening of helium lines, by non local thermodynamic equilibrium (LTE) work for ...
openaire   +1 more source

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 Shewanella oneidensis Fic enzyme SoFic targets the switch‐I region of EF‐Tu for AMPylation

FEBS Letters, EarlyView.
Fic enzymes mediate diverse post‐translational modifications across all domains of life, including AMPylation. Prokaryotic EF‐Tu can be AMPylated and deAMPylated by the conserved Fic enzyme SoFic. Structural and biochemical approaches were used to characterize the effect of AMPylation on EF‐Tu, SoFic's enzymatic activities, and the enzyme‐target ...
Svenja Runge, Vivian Pogenberg, Alexander Baumgart, Bente Siebels, Hartmut Schlüter, Michael Hecht‐Bucher, Aymelt Itzen   +6 more
wiley   +1 more source

Chiral separation of chloroalkanes with the chromatographic column onboard Martian rovers

FEBS Letters, EarlyView.
Computer image of the Rosalind Franklin Rover of ESA's ExoMars mission. ExoMars is scheduled to land on planet Mars in Oxia Planum in 2029. This area represents an interesting spot to look for biosignatures. Investigations of ExoMars include measurement on molecular chirality. We show that chiral chloroalkanes, that have been identified on Mars, can be
Asma Merzougui, Agnes Banreti, Armelle L. Ernst, Guillaume Leseigneur, Uwe J. Meierhenrich   +4 more
wiley   +1 more source

The Abundance of Helium in Stellar Interiors [PDF]

Highlights of Astronomy, 1971
From the titles of the other contributions to this morning’s session, one deduces that the hard facts of theory are to be sandwiched between the loose speculations of direct observation. I shall therefore feel free to discuss theoretical implications from stellar structure unencumbered by what are, after all, but peripheral considerations.I should ...
openaire   +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

Primordial Lithium from Globular Cluster Turnoff Stars: M13 and M71

The Astrophysical Journal
During Big Bang nucleosynthesis (BBN) in the first 15 minutes of the Universe, some ^7 Li was created along with isotopes of H and He. The determination of that primordial value of Li can help constrain the conditions at that time.
Ann Merchant Boesgaard, Constantine P. Deliyannis   +1 more
doaj   +1 more source

Inferring stellar compositions [PDF]

EPJ Web of Conferences
Stars are not hydrostatic spheres and their atmospheric layers are not in local thermodynamic equilibrium. Inferring stellar surface abundances from such 1D+LTE models is subject to significant biases.
Korn Andreas J.
doaj   +1 more source

The heterodimeric amino acid transporters (HAT) of the SLC7/SLC3 family: A structure−function relationships and relevance to human pathology

FEBS Letters, EarlyView.
Heterodimeric amino acid transporters consist of SLC7 and SLC3 family proteins arranged in a conserved structural organization. They regulate nutrient transport across cell membranes, supporting essential cellular functions. These transporters also contribute to xenobiotic/drug uptake and distribution.
Mariafrancesca Scalise, Tiziano Mazza, Raffaella Scanga, Lara Console, Michele Galluccio, Cesare Indiveri   +5 more
wiley   +1 more source

A context‐dependent modulatory role for eIF6 in acquired resistance to vemurafenib in melanoma

FEBS Letters, EarlyView.
Acquired resistance to vemurafenib upregulates the translation factor eIF6 in melanoma cells. Silencing eIF6 in resistant cells reduces proliferation and partially restores drug sensitivity, whereas its overexpression increases sensitivity across melanoma lines regardless of BRAF status, via modulation of mTOR, S6K, and MAPK signaling.
George Kyriakopoulos, Antonia Petropoulou, Alexandra Anastogianni, Angelina Bania, Vassilis Stamatakis, Argyris Alexiou, Chi‐Ping Day, Glenn Merlino, Katerina Grafanaki, Constantinos Stathopoulos   +9 more
wiley   +1 more source