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Dating the skull from Broken Hill, Zambia, and its position in human evolution 期刊论文
NATURE, 2020, 580 (7803) : 372-+
作者:  Mergner, Julia;  Frejno, Martin;  List, Markus;  Papacek, Michael;  Chen, Xia;  Chaudhary, Ajeet;  Samaras, Patroklos;  Richter, Sandra;  Shikata, Hiromasa;  Messerer, Maxim;  Lang, Daniel;  Altmann, Stefan;  Cyprys, Philipp;  Zolg, Daniel P.;  Mathieson, Toby;  Bantscheff, Marcus
收藏  |  浏览/下载:5/0  |  提交时间:2020/07/03

The cranium from Broken Hill (Kabwe) was recovered from cave deposits in 1921, during metal ore mining in what is now Zambia(1). It is one of the best-preserved skulls of a fossil hominin, and was initially designated as the type specimen of Homo rhodesiensis, but recently it has often been included in the taxon Homo heidelbergensis(2-4). However, the original site has since been completely quarried away, and-although the cranium is often estimated to be around 500 thousand years old(5-7)-its unsystematic recovery impedes its accurate dating and placement in human evolution. Here we carried out analyses directly on the skull and found a best age estimate of 299 +/- 25 thousand years (mean +/- 2s). The result suggests that later Middle Pleistocene Africa contained multiple contemporaneous hominin lineages (that is, Homo sapiens(8,9), H. heidelbergensis/H. rhodesiensis and Homo naledi(10,11)), similar to Eurasia, where Homo neanderthalensis, the Denisovans, Homo floresiensis, Homo luzonensis and perhaps also Homo heidelbergensis and Homo erectus(12) were found contemporaneously. The age estimate also raises further questions about the mode of evolution of H. sapiens in Africa and whether H. heidelbergensis/H. rhodesiensis was a direct ancestor of our species(13,14).


  
Redox-switchable carboranes for uranium capture and release 期刊论文
NATURE, 2020, 577 (7792) : 652-+
作者:  Marques, Joao C.;  Li, Meng;  Schaak, Diane;  Robson, Drew N.;  Li, Jennifer M.
收藏  |  浏览/下载:31/0  |  提交时间:2020/07/03

The uranyl ion (UO22+  U(vi) oxidation state) is the most common form of uranium found in terrestrial and aquatic environments and is a central component in nuclear fuel processing and waste remediation efforts. Uranyl capture from either seawater or nuclear waste has been well studied and typically relies on extremely strong chelating/binding affinities to UO22+ using chelating polymers(1,2), porous inorganic(3-5) or carbon-based(6,7) materials, as well as homogeneous(8) compounds. By contrast, the controlled release of uranyl after capture is less established and can be difficult, expensive or destructive to the initial material(2,9). Here we show how harnessing the redox-switchable chelating and donating properties of an ortho-substituted closo-carborane (1,2-(Ph2PO)(2)-1,2-C2B10H10) cluster molecule can lead to the controlled chemical or electrochemical capture and release of UO22+ in monophasic (organic) or biphasic (organic/aqueous) model solvent systems. This is achieved by taking advantage of the increase in the ligand bite angle when the closo-carborane is reduced to the nido-carborane, resulting in C-C bond rupture and cage opening. The use of electrochemical methods for uranyl capture and release may complement existing sorbent and processing systems.


Redox-switchable chelation is demonstrated for a carborane cluster molecule, leading to controlled chemical or electrochemical capture and release of uranyl in monophasic or biphasic model solvent systems.


  
Last appearance of Homo erectus at Ngandong, Java, 117,000-108,000 years ago 期刊论文
NATURE, 2020, 577 (7790) : 381-+
作者:  Haldane, Andy
收藏  |  浏览/下载:29/0  |  提交时间:2020/04/16

Homo erectus is the founding early hominin species of Island Southeast Asia, and reached Java (Indonesia) more than 1.5 million years ago(1,2). Twelve H. erectus calvaria (skull caps) and two tibiae (lower leg bones) were discovered from a bone bed located about 20 m above the Solo River at Ngandong (Central Java) between 1931 and 1933(3,4), and are of the youngest, most-advanced form of H. erectus(5-8). Despite the importance of the Ngandong fossils, the relationship between the fossils, terrace fill and ages have been heavily debated(9-14). Here, to resolve the age of the Ngandong evidence, we use Bayesian modelling of 52 radiometric age estimates to establish-to our knowledg-the first robust chronology at regional, valley and local scales. We used uranium-series dating of speleothems to constrain regional landscape evolution  luminescence, (40)argon/(39)argon (Ar-40/Ar-39) and uranium-series dating to constrain the sequence of terrace evolution  and applied uranium-series and uranium series-electron-spin resonance (US-ESR) dating to non-human fossils to directly date our re-excavation of Ngandong(5,15). We show that at least by 500 thousand years ago (ka) the Solo River was diverted into the Kendeng Hills, and that it formed the Solo terrace sequence between 316 and 31 ka and the Ngandong terrace between about 140 and 92 ka. Non-human fossils recovered during the re-excavation of Ngandong date to between 109 and 106 ka (uranium-series minimum)(16) and 134 and 118 ka (US-ESR), with modelled ages of 117 to 108 thousand years (kyr) for the H. erectus bone bed, which accumulated during flood conditions(3,17). These results negate the extreme ages that have been proposed for the site and solidify Ngandong as the last known occurrence of this long-lived species.


  
The neural basis of combinatory syntax and semantics 期刊论文
SCIENCE, 2019, 366 (6461) : 62-66
作者:  Pylkkanen, Liina
收藏  |  浏览/下载:6/0  |  提交时间:2019/11/27
Plant-thickening mechanisms revealed 期刊论文
NATURE, 2019, 565 (7740) : 433-435
作者:  Wolf, Sebastian;  Lohmann, Jan U.
收藏  |  浏览/下载:7/0  |  提交时间:2019/11/27
SCIENCE POLICY U.S. science adviser sees smaller federal role 期刊论文
SCIENCE, 2019, 363 (6429) : 800-801
作者:  Mervis, Jeffrey
收藏  |  浏览/下载:0/0  |  提交时间:2019/11/27
Response to Comment on "U-Th dating of carbonate crusts reveals Neandertal origin of Iberian cave art" 期刊论文
SCIENCE, 2018, 362 (6411)
作者:  Hoffmann, D. L.;  Standish, C. D.;  Garcia-Diez, M.;  Pettitt, P. B.;  Milton, J. A.;  Zilhao, J.;  Alcolea-Gonzalez, J. J.;  Cantalejo-Duarte, P.;  Collado, H.;  de Balbin, R.;  Lorblanchet, M.;  Ramos-Munoz, J.;  Weniger, G-Ch.;  Pike, A. W. G.
收藏  |  浏览/下载:7/0  |  提交时间:2019/11/27
The making of a plankton toxin 期刊论文
SCIENCE, 2018, 361 (6409) : 1308-1309
作者:  Pohnert, Georg;  Poulin, Remington X.;  Baumeister, Tim U. H.
收藏  |  浏览/下载:4/0  |  提交时间:2019/11/27
A gut feeling Gut-brain signaling involves neurotransmission from gut sensory epithelial cells 期刊论文
SCIENCE, 2018, 361 (6408) : 1203-1204
作者:  Hoffman, Benjamin U.;  Lumpkin, Ellen A.
收藏  |  浏览/下载:0/0  |  提交时间:2019/11/27
Changing dynamics of the drug overdose epidemic in the United States from 1979 through 2016 期刊论文
SCIENCE, 2018, 361 (6408) : 1218-+
作者:  Jalal, Hawre;  Buchanich, Jeanine M.;  Roberts, Mark S.;  Balmert, Lauren C.;  Zhang, Kun;  Burke, Donald S.
收藏  |  浏览/下载:5/0  |  提交时间:2019/11/27