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The genetic information of the Chinese Tibetan group has been a long-standing research hotspot among population geneticists and archaeologists. Herein, 309 unrelated individuals from two Tibetan groups living in Qinghai Province, China (CTQ), and Tibet Autonomous Region, China (CTT), were successfully genotyped using a new homemade six-color fluorescence multiplex panel, which contained 59 autosomal deletion/insertion polymorphisms (au-DIPs), two mini short tandem repeats (miniSTRs), two Y-chromosomal DIPs, and one Amelogenin. The cumulative probability of matching and combined power of exclusion values for this new panel in CTQ and CTT groups were 1.9253E-27 and 0.99999729, as well as 1.5061E-26 and 0.99999895, respectively. Subsequently, comprehensive population genetic analyses of Tibetan groups and reference populations were carried out based on the 59 au-DIPs. The multitudinous statistical analysis results supported that Tibetan groups have close genetic affinities with East Asian populations. These findings showed that this homemade system would be a powerful tool for forensic individual identification and paternity testing in Chinese Tibetan groups and give us an important insight for further perfecting the genetic landscape of Tibetan groups. [ABSTRACT FROM AUTHOR]

Rainfall, especially rainstorm, is a major factor in inducing loess-mudstone landslides and plays an essential role in landslide reactivation. The aim of the paper is to study the triggering mechanism and reactivation probability of a loess-mudstone landslide induced by rainfall infiltration in Qinghai Province, Northwestern China. According to the numerical model of elastic–plastic mechanics, the triggering mechanism of loess-mudstone landslides was revealed. Then, the reactivation probability of the potential landslide was evaluated by the combination of the limit equilibrium and Monte-Carlo methods. For one thing, the relationship between water content and shear strength of media was analyzed based on the mechanical test of materials. For another, the effects of rainfall conditions were analyzed on the distribution of water content in the aerated zone with the two-dimensional coupling model of unsaturated–saturated seepage. The results show that the shear strength of media is very sensitive to water content because of water–rock interaction including hydration and dissolution. Besides, the water content significantly increases at the interface between the loess and mudstone after the rainstorm occurring owing to the permeability heterogeneous of media and topographic feature, which leads to the strength deterioration. Although the whole landslide is stable in the rainstorm conditions, its middle part can be reactivated along the original sliding zone with high probability by a geomechanical model of sliding-tension. Therefore, the landslide reactivation is controlled by the water sensitivity of media, the permeability heterogeneous of media, the topographic feature and the original sliding zone, especially the original sliding zone. This research provides a valuable reference for the occurrence and reactivation of similar landslides. [ABSTRACT FROM AUTHOR]

Abstract: The 14 April 2010 Mw 6.9 Yushu earthquake ruptured the northwestern segment of the Ganzi-Yushu fault in Qinghai Province, China. Using GPS data obtained from 1999 to 2007 in the vicinity of the Ganzi-Yushu fault, we estimate the slip rates of the Fenghuoshan and Ganzi-Yushu faults, and the northwestern segment of the Xianshuihe fault as 6.1±1.9, 6.6±1.5, and 9.7±0.7mm/a for left lateral components, and 2.8±1.9, 1.7±1.6, and −2.0±0.9mm/a for shortening components, respectively. The Maduo-Gande fault slips left laterally at a rate of about 1–2mm/a, and ~3mm/a sinistral shear motion is left unexplained, possibly caused by deformation across one or more unknown faults in the region. These results agree with geological estimates of the fault slip rates, and show a progressive increase of shear motion from northwest to southeast across segments of the Xianshuihe–Ganzi-Yushu fault zone, implying variation in transferring and absorbing deformation in different regions in and around the Tibetan plateau. [Copyright &y& Elsevier]