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109 - Kang Hu , Shi Yan , Kai Liu 2015
Haplogroup N-M231 of human Y chromosome is a common clade from Eastern Asia to Northern Europe, being one of the most frequent haplogroups in Altaic and Uralic-speaking populations. Using newly discovered bi-allelic markers from high-throughput DNA s equencing, we largely improved the phylogeny of Haplogroup N, in which 16 subclades could be identified by 33 SNPs. More than 400 males belonging to Haplogroup N in 34 populations in China were successfully genotyped, and populations in Northern Asia and Eastern Europe were also compared together. We found that all the N samples were typed as inside either clade N1-F1206 (including former N1a-M128, N1b-P43 and N1c-M46 clades), most of which were found in Altaic, Uralic, Russian and Chinese-speaking populations, or N2-F2930, common in Tibeto-Burman and Chinese-speaking populations. Our detailed results suggest that Haplogroup N developed in the region of China since the final stage of late Paleolithic Era.
Demographic change of human populations is one of the central questions for delving into the past of human beings. To identify major population expansions related to male lineages, we sequenced 78 East Asian Y chromosomes at 3.9 Mbp of the non-recomb ining region (NRY), discovered >4,000 new SNPs, and identified many new clades. The relative divergence dates can be estimated much more precisely using molecular clock. We found that all the Paleolithic divergences were binary; however, three strong star-like Neolithic expansions at ~6 kya (thousand years ago) (assuming a constant substitution rate of 1e-9/bp/year) indicates that ~40% of modern Chinese are patrilineal descendants of only three super-grandfathers at that time. This observation suggests that the main patrilineal expansion in China occurred in the Neolithic Era and might be related to the development of agriculture.
494 - Shi-Yan Zhang 2008
Type II AGNs with polarimetric broad emission line provided strong evidence for the orientation-based unified model for AGNs. We want to investigate whether the polarimetric broad emission line in type II AGNs can be used to calculate their central s upermassive black hole (SMBH) masses, like that for type I AGNs. We collected 12 type II AGNs with polarimetric broad emission line width from the literatures, and calculated their central black hole masses from the polarimetric broad line width and the isotropic oiii luminosity. We also calculate the mass from stellar velocity dispersion, $sigma_*$, with the $mbh-sigma_*$ relation.We find that: (1) the black hole masses derived from the polarimetric broad line width is averagely larger than that from the $mbh- sigma_*$ relation by about 0.6 dex, (2) If these type II AGNs follow $mbh-sigma_*$ relation, we find that the random velocity cant not be omitted and is comparable with the BLRs Keplerian velocity. It is consistent with the scenery of large outflow from the accretion disk suggested by Yong et al.
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