88 research outputs found
Oxygen sensing and integrative stress signaling in plants
Schmidt R, Weits DA, Feulner CFJ, van Dongen JT. Oxygen Sensing and Integrative Stress Signaling in Plants. Plant Physiology. 2018;176(2):1131-1142
Environment and self-regulation in galaxy formation
The environment is known to affect the formation and evolution of galaxies considerably best visible through the well-known morphology–density relationship. It is less clear, though, whether the environment is equally important at a given galaxy morphology. In this paper, we study the effect of environment on the evolution of early-type galaxies as imprinted in the fossil record by analysing the stellar population properties of 3360 galaxies morphologically selected by visual inspection from the Sloan Digital Sky Survey in a narrow redshift range ( 0.05 ≤z≤ 0.06 ). The morphological selection algorithm is critical, as it does not bias against recent star formation. We find that the distribution of ages is bimodal with a strong peak at old ages and a secondary peak at young ages around ∼2.5 Gyr containing about 10 per cent of the objects. This is an analogue to 'red sequence' and 'blue cloud' identified in galaxy populations usually containing both early- and late-type galaxies. The fraction of the young, rejuvenated galaxies increases with both decreasing galaxy mass and decreasing environmental density up to about 45 per cent, which implies that the impact of environment increases with decreasing galaxy mass. The rejuvenated galaxies have lower α/Fe ratios than the average and most of them show signs of ongoing star formation through their emission line spectra. All objects that host active galactic nuclei in their centres without star formation are part of the red sequence population. We confirm and statistically strengthen earlier results that luminosity weighted ages, metallicities and α/Fe element ratios of the red sequence population correlate well with velocity dispersion and galaxy mass. Most interestingly, however, these scaling relations are not sensitive to environmental densities and are only driven by galaxy mass. We infer that early-type galaxy formation has undergone a phase transition a few billion years ago around z∼ 0.2 . A self-regulated formation phase without environmental dependence has recently been superseded by a rejuvenation phase, in which the environment plays a decisive role possibly through galaxy mergers and interactions
Eine kanonische Form zur Darstellung äquivalenter Codes : Computergestützte Berechnung und ihre Anwendung in der Codierungstheorie, Kryptographie und Geometrie
Use of domesticated pigs by Mesolithic hunter-gatherers in northwestern Europe
Acknowledgements We thank the Archaeological State Museum Schleswig-Holstein, the Archaeological State Offices of Brandenburg, Lower Saxony and Saxony and the following individuals who provided sample material: Betty Arndt, Jo¨rg Ewersen, Frederick Feulner, Susanne Hanik, Ru¨diger Krause, Jochen Reinhard, Uwe Reuter, Karl-Heinz Ro¨hrig, Maguerita Scha¨fer, Jo¨rg Schibler, Reinhold Schoon, Regina Smolnik, Thomas Terberger and Ingrid Ulbricht. We are grateful to Ulrich Schmo¨lcke, Michael Forster, Peter Forster and Aikaterini Glykou for their support and comments on the manuscript. We also thank many institutions and individuals that provided sample material and access to collections, especially the curators of the Museum fu¨r Naturkunde, Berlin; Muse´um National d0 Histoire Naturelle, Paris; Smithsonian Institution, National Museum of Natural History, Washington D.C.; Zoologische Staatssammlung, Mu¨nchen; Museum fu¨r Haustierkunde, Halle; the American Museum of Natural History, New-York. This work was funded by the Graduate School ‘Human Development in Landscapes’ at Kiel University (CAU) and supported by NERC project Grant NE/F003382/1. Radiocarbon dating was carried out at the Leibniz Laboratory, CAU. This work is licensed under a Creative Commons AttributionNonCommercial-NoDerivs 3.0 Unported License.Peer reviewe
The automorphism group of an extremal [72,36,16] code does not contain Z7, Z3 x Z3, or D10
Identifizierung von Morbus Alzheimer Kandidatengenen auf Basis der Einzelnukleotid-Polymorphismus Genotypisierung
- …
