Results 111 to 120 of about 5,954,141 (263)

Past aridity and dust drove biodiversity crises and altered pollination in the ancient gymnosperm Ephedra (Gnetales)

Biological Reviews, EarlyView.
ABSTRACT The long‐term effects of present‐day climate change on pollination are unquantified. However, distinguishing climatic drivers of ancient changes in pollination could provide valuable insights into biotic responses to near‐future climate states.
Natasha Barbolini, Niels Meijer, Carina Hoorn, Guillaume Dupont‐Nivet, Fang Han, Ashley Krüger, Qin Yuan, Alexander Rohrmann, Kristina Bolinder, Catarina Rydin   +9 more
wiley   +1 more source

Low temperature formation of pyridine and (iso)quinoline via neutral neutral reactions [PDF]

Aromatic molecules represent fundamental building blocks in prebiotic chemistry and are contemplated as vital precursors to DNA and RNA nitrogen bases. However, despite the identification of some 300 molecules in extraterrestrial environments, the pathways to pyridine (C5H5N), pyridinyl (C5H4N), and (iso)quinoline (C9H7N) the simplest representative of
arxiv   +1 more source

Mineral Surface Rearrangement at High Temperatures: Implications for Extraterrestrial Mineral Grain Reactivity

ACS Earth and Space Chemistry, 2017
Mineral surfaces play a critical role in the solar nebula as a catalytic surface for chemical reactions and potentially acted as a source of water during Earth’s accretion by the adsorption of water molecules to the surface of interplanetary dust ...
H. King, O. Plümper, C. Putnis, H. O’Neill, S. Klemme, A. Putnis   +5 more
semanticscholar   +1 more source

The Mission (Im)possible of Climate Action through Quixotic Institutional Work

Journal of Management Studies, EarlyView.
Abstract The ‘iron cage’ of the (neo‐) liberal‐capitalist system prioritizes economic returns over climate protection. Formerly powerful nation‐states are subordinated to the rule of markets, whereas business elites have been freed from substantial responsibility for social and environmental concerns.
Giuseppe Delmestri, Elke S. Schuessler
wiley   +1 more source

Crossed Molecular Beam Experiments of Radical-Neutral Reactions Relevant to the Formation of Hydrogen Deficient Molecules in Extraterrestrial Environments [PDF]

, 2000
Ralf I. Kaiser, Nadia Balucani, Oskar Asvany, Y. T. Lee   +3 more
openalex   +1 more source

DEM simulation of soil-tool interaction under extraterrestrial environmental effects [PDF]

arXiv, 2019
In contrast to terrestrial environment, the harsh lunar environment conditions include lower gravity acceleration, ultra-high vacuum and high (low) temperature in the daytime (night-time). This paper focuses on the effects of those mentioned features on soil cutting tests, a simplified excavation test, to reduce the risk of lunar excavation missions ...
arxiv  

The petrology of the Ozerki meteorite constrained by electron backscatter diffraction and X‐ray computed tomography

Meteoritics &Planetary Science, EarlyView.
Abstract Combining electron backscatter diffraction (EBSD) with X‐ray computed tomography (XCT) offers a comprehensive approach to investigate shock deformation and rock texture in meteorites, yet such integration remains uncommon. In this study, we demonstrate the synergistic potential of XCT and EBSD in revealing deformation metrics, thereby ...
Alice Macente, Luke Daly, Sammy Griffin, Maria Gritsevich, Jarmo Moilanen, Josh Franz Einsle, Patrick Trimby, Chris Mulcahy, Jonathan Moffat, Alexander M. Ruzicka   +9 more
wiley   +1 more source

IMPERA: Integrated Mission Planning for Multi-Robot Systems

Robotics, 2015
This paper presents the results of the project IMPERA (Integrated Mission Planning for Distributed Robot Systems). The goal of IMPERA was to realize an extraterrestrial exploration scenario using a heterogeneous multi-robot system. The main challenge was
Daniel Saur, Kurt Geihs
doaj   +1 more source

Hydration and dehydration of CM chondrites revealed by X‐ray diffraction combined with textural observations and compositional data

Meteoritics &Planetary Science, EarlyView.
Abstract The in‐plane rotation method is used to obtain X‐ray random diffraction (XRD) patterns of polished thin sections of 10 CM chondrites. The samples include five intermediately altered CM chondrites with subtypes 2.6–2.3, two heavily altered CM chondrites with subtype 2.0 and three with secondary heating after hydration (Y 980036, Y 980051, and ...
Naoya Imae, Makoto Kimura, Akira Yamaguchi   +2 more
wiley   +1 more source

Efficient Adaptation of Deep Neural Networks for Semantic Segmentation in Space Applications [PDF]

arXiv
In recent years, the application of Deep Learning techniques has shown remarkable success in various computer vision tasks, paving the way for their deployment in extraterrestrial exploration. Transfer learning has emerged as a powerful strategy for addressing the scarcity of labeled data in these novel environments.
arxiv