Publications by authors named "L M E Percival"

Marine tetrapods occupy important roles in modern marine ecosystems and often gather in large aggregations driven by patchy prey distribution, social or reproductive behaviors, or oceanographic factors. Here, we show that similar grouping behaviors evolved in an early marine tetrapod lineage, documented by dozens of specimens of the giant ichthyosaur Shonisaurus in the Luning Formation in West Union Canyon, Nevada, USA. A concentration of at least seven skeletons closely preserved on a single bedding plane received the bulk of previous attention.

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The biogeochemical cycle of trace metals and oxyanions in marine sediments is mainly controlled by early diagenesis of organic material, but anthropogenic activities such as dumping of dredged sludge or shipyard activities can strongly perturb these natural processes. Therefore, the impact of dumping of dredged sludge, shipyard activities such as blasting of boat hulls and the mixing of polluted Scheldt estuary water with less polluted coastal water on the mobilization of trace metals and oxyanions in the sediments was studied in the pre- and post-bloom period (March and October) in Belgian Coastal Zone (BCZ). Vertical profiles of total and labile dissolved trace element concentrations, dissolved sulfide, pH and redox potential were assessed in sediment porewaters.

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The assembly of complexes following the detection of extracellular signals is often controlled by signaling proteins comprising multiple peptide binding modules. The SRC homology (SH)3 family represents the archetypical modular protein interaction module, with ~300 annotated SH3 domains in humans that regulate an impressive array of signaling processes. We review recent findings regarding the allosteric contributions of SH3 domains host protein context, their phosphoregulation, and their roles in phase separation that challenge the simple model in which SH3s are considered to be portable domains binding to specific proline-rich peptide motifs.

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The Devonian Frasnian-Famennian (F-F) boundary marks one of the five main extinction intervals of the Phanerozoic Aeon. This time was characterized by two pulses of oceanic anoxia, named the Lower and Upper Kellwasser events, during which massive marine biodiversity losses occurred. This paper presents high-resolution magnetic susceptibility, X-ray fluorescence elemental geochemistry and carbon isotope datasets obtained from the Steinbruch Schmidt F-F boundary section (Germany).

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The Frasnian-Famennian boundary records one of the most catastrophic mass extinctions of the Phanerozoic Eon. Several possible causes for this extinction have been suggested, including extra-terrestrial impacts and large-scale volcanism. However, linking the extinction with these potential causes is hindered by the lack of precise dating of either the extinction or volcanic/impact events.

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