223 research outputs found

    The Peopling of Europe from the Mitochondrial Haplogroup U5 Perspective

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    It is generally accepted that the most ancient European mitochondrial haplogroup, U5, has evolved essentially in Europe. To resolve the phylogeny of this haplogroup, we completely sequenced 113 mitochondrial genomes (79 U5a and 34 U5b) of central and eastern Europeans (Czechs, Slovaks, Poles, Russians and Belorussians), and reconstructed a detailed phylogenetic tree, that incorporates previously published data. Molecular dating suggests that the coalescence time estimate for the U5 is ∌25–30 thousand years (ky), and ∌16–20 and ∌20–24 ky for its subhaplogroups U5a and U5b, respectively. Phylogeographic analysis reveals that expansions of U5 subclusters started earlier in central and southern Europe, than in eastern Europe. In addition, during the Last Glacial Maximum central Europe (probably, the Carpathian Basin) apparently represented the area of intermingling between human flows from refugial zones in the Balkans, the Mediterranean coastline and the Pyrenees. Age estimations amounting for many U5 subclusters in eastern Europeans to ∌15 ky ago and less are consistent with the view that during the Ice Age eastern Europe was an inhospitable place for modern humans

    Electron spectroscopy of nanocrystalline diamond surfaces

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    Thin, fully optically transparent nanocrystalline diamond (NCD) films prepared at growth temperatures from 400 °C to 1100 °C were well characterized by SEM, AFM, and by angularresolved x-ray photoelectron spectroscopy (ARXPS). The ARXPS spectra were applied for estimating the extent of sp 3 hybridization of carbon atoms in a surface region of the NCD films. Elastic peak electron spectroscopy (EPES) was used for assessment of the inelastic mean free path (IMFP) values of electrons in NCD films in the electron energy range 200 eV -2400 eV. The resulting IMFPs were compared to the IMFPs calculated from the optical data and from the TPP-2M predictive formulae
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