86 research outputs found

    Re-evaluating the resource potential of lomas fog oasis environments for Preceramic hunter-gatherers under past ENSO modes on the south coast of Peru

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    Lomas – ephemeral seasonal oases sustained by ocean fogs – were critical to ancient human ecology on the desert Pacific coast of Peru: one of humanity’s few independent hearths of agriculture and “pristine” civilisation. The role of climate change since the Late Pleistocene in determining productivity and extent of past lomas ecosystems has been much debated. Here we reassess the resource potential of the poorly studied lomas of the south coast of Peru during the long Middle Pre-ceramic period (c. 8,000 – 4,500 BP): a period critical in the transition to agriculture, the onset of modern El Niño Southern Oscillation (‘ENSO’) conditions, and eustatic sea-level rise and stabilisation and beach progradation. Our method combines vegetation survey and herbarium collection with archaeological survey and excavation to make inferences about both Preceramic hunter-gatherer ecology and the changed palaeoenvironments in which it took place. Our analysis of newly discovered archaeological sites – and their resource context – show how lomas formations defined human ecology until the end of the Middle Preceramic Period, thereby corroborating recent reconstructions of ENSO history based on other data. Together, these suggest that a five millennia period of significantly colder seas on the south coast induced conditions of abundance and seasonal predictability in lomas and maritime ecosystems, that enabled Middle Preceramic hunter-gatherers to reduce mobility by settling in strategic locations at the conïŹ‚uence of multiple eco-zones at the river estuaries. Here the foundations of agriculture lay in a Broad Spectrum Revolution that unfolded, not through population pressure in deteriorating environments, but rather as an outcome of resource abundance.We thank the Ministerio de Cultural del PerĂș for granting permission for archaeological fieldwork (ResoluciĂłn Directoral NÂș 933-2012-DGPC-VMPCIC/MC, 19 December 2012 and NÂș 386-2014-DGPA-VMPCIC/MC, 22 August 2014) and the export of samples for dating; Don Alberto Benavides Ganoza and the people of Samaca for facilitating fieldwork; the Leverhulme Trust (grant number RPG-117) and the late Don Alberto Benavides de la Quintana (grant number RG69428) and the McDonald Institute for Archaeological Research for funding Cambridge University’s One River Archaeological Project, and the NERC Radiocarbon facility (grant number NF/2013/2/2) for funding radiocarbon dating. We also thank the Servicio Nacional Forestal y de Fauna Silvestre (SERFOR) and the Servicio Nacional de Áreas Naturales Protegidas por el Estado (SERNANP), Peru for permits for the Proyecto Kew PerĂș to carry out botanical and ecological survey, and Delsy Trujillo, Eric RamĂ­rez, Consuelo Borda and other participants of the Proyecto Kew PerĂș: ConservaciĂłn, RestauraciĂłn de HĂĄbitats y Medios de Vida Útiles, Ica, Peru.This is the final version of the article. It first appeared from Elsevier via http://dx.doi.org/10.1016/j.quascirev.2015.10.02

    Observation of Two New Excited Ξb0 States Decaying to Λb0 K-π+

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    Two narrow resonant states are observed in the Λb0K-π+ mass spectrum using a data sample of proton-proton collisions at a center-of-mass energy of 13 TeV, collected by the LHCb experiment and corresponding to an integrated luminosity of 6 fb-1. The minimal quark content of the Λb0K-π+ system indicates that these are excited Ξb0 baryons. The masses of the Ξb(6327)0 and Ξb(6333)0 states are m[Ξb(6327)0]=6327.28-0.21+0.23±0.12±0.24 and m[Ξb(6333)0]=6332.69-0.18+0.17±0.03±0.22 MeV, respectively, with a mass splitting of Δm=5.41-0.27+0.26±0.12 MeV, where the uncertainties are statistical, systematic, and due to the Λb0 mass measurement. The measured natural widths of these states are consistent with zero, with upper limits of Γ[Ξb(6327)0]<2.20(2.56) and Γ[Ξb(6333)0]<1.60(1.92) MeV at a 90% (95%) credibility level. The significance of the two-peak hypothesis is larger than nine (five) Gaussian standard deviations compared to the no-peak (one-peak) hypothesis. The masses, widths, and resonant structure of the new states are in good agreement with the expectations for a doublet of 1D Ξb0 resonances

    A Genome-Wide Association Study of Diabetic Kidney Disease in Subjects With Type 2 Diabetes

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    dentification of sequence variants robustly associated with predisposition to diabetic kidney disease (DKD) has the potential to provide insights into the pathophysiological mechanisms responsible. We conducted a genome-wide association study (GWAS) of DKD in type 2 diabetes (T2D) using eight complementary dichotomous and quantitative DKD phenotypes: the principal dichotomous analysis involved 5,717 T2D subjects, 3,345 with DKD. Promising association signals were evaluated in up to 26,827 subjects with T2D (12,710 with DKD). A combined T1D+T2D GWAS was performed using complementary data available for subjects with T1D, which, with replication samples, involved up to 40,340 subjects with diabetes (18,582 with DKD). Analysis of specific DKD phenotypes identified a novel signal near GABRR1 (rs9942471, P = 4.5 x 10(-8)) associated with microalbuminuria in European T2D case subjects. However, no replication of this signal was observed in Asian subjects with T2D or in the equivalent T1D analysis. There was only limited support, in this substantially enlarged analysis, for association at previously reported DKD signals, except for those at UMOD and PRKAG2, both associated with estimated glomerular filtration rate. We conclude that, despite challenges in addressing phenotypic heterogeneity, access to increased sample sizes will continue to provide more robust inference regarding risk variant discovery for DKD.Peer reviewe

    Precise determination of the B-s(0)-B-s(-0) oscillation frequency

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    Mesons comprising a beauty quark and a strange quark can oscillate between particle (B0s) and antiparticle (B0s) flavour eigenstates, with a frequency given by the mass difference between heavy and light mass eigenstates, deltams. Here we present ameasurement of deltams using B0s2DsPi decays produced in proton-proton collisions collected with the LHCb detector at the Large Hadron Collider. The oscillation frequency is found to be deltams = 17.7683 +- 0.0051 +- 0.0032 ps-1, where the first uncertainty is statistical and the second systematic. This measurement improves upon the current deltams precision by a factor of two. We combine this result with previous LHCb measurements to determine deltams = 17.7656 +- 0.0057 ps-1, which is the legacy measurement of the original LHCb detector.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2021-005.html (LHCb public pages

    Angular Analysis of the B+ -> K*(+)mu(+) mu(-) Decay

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    We present an angular analysis of the B + → K * + ( → K 0 S π + ) ÎŒ + ÎŒ − decay using 9     fb − 1 of p p collision data collected with the LHCb experiment. For the first time, the full set of C P -averaged angular observables is measured in intervals of the dimuon invariant mass squared. Local deviations from standard model predictions are observed, similar to those in previous LHCb analyses of the isospin-partner B 0 → K * 0 ÎŒ + ÎŒ − decay. The global tension is dependent on which effective couplings are considered and on the choice of theory nuisance parameters
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