Publications by authors named "M P Chapot"

Wood artefacts rarely survive from the Early Stone Age since they require exceptional conditions for preservation; consequently, we have limited information about when and how hominins used this basic raw material. We report here on the earliest evidence for structural use of wood in the archaeological record. Waterlogged deposits at the archaeological site of Kalambo Falls, Zambia, dated by luminescence to at least 476 ± 23 kyr ago (ka), preserved two interlocking logs joined transversely by an intentionally cut notch.

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Article Synopsis
  • Despite extensive fossil discoveries in eastern Africa, the environmental context of hominin evolution remains unclear due to insufficient continuous records, particularly for the Pleistocene epoch.
  • A new 620,000-year environmental record from Chew Bahir in southern Ethiopia reveals how climate variability may have impacted hominin biological and cultural changes, highlighting significant shifts in habitats.
  • The study identifies key climatic phases that correlate with major technological and social advancements in hominins, suggesting that environmental conditions played a crucial role in their evolution and eventual dispersal.
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Rock art compels interest from both researchers and a broader public, inspiring many hypotheses about its cultural origin and meaning, but it is notoriously difficult to date numerically. Barrier Canyon-style (BCS) pictographs of the Colorado Plateau are among the most debated examples; hypotheses about its age span the entire Holocene epoch and previous attempts at direct radiocarbon dating have failed. We provide multiple age constraints through the use of cross-cutting relations and new and broadly applicable approaches in optically stimulated luminescence dating at the Great Gallery panel, the type section of BCS art in Canyonlands National Park, southeastern Utah.

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After fusion with the N-proximal portion of the outer membrane protein LamB, three beta-adrenergic receptors, the human beta 1- and beta 2- and turkey beta 1-adrenergic receptor, were expressed in Escherichia coli with retention of their own specific pharmacological properties. Molecular characterization and localization of the three receptors in bacteria and comparison of the behaviour of each hybrid protein are reported. The bacteria were lysed and fractionated on a sucrose gradient.

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