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The Qinghai-Tibet Plateau (QTP) is an area with highly distinctive natural and socio-cultural characteristics. In recent years, the pastoral areas of northern Tibet have undergone a phase transition from nomadic to settled grazing, and the settlement system is in a stage of formation and evolution. Against the backdrop of China's new strategy of rural revitalization, conducting associated research on the evolution of the settlement system and the prospect of rural revitalization is of great significance for improving the living and working conditions of herdsmen in alpine pastoral areas and promoting sustainable development on the QTP. Using settlement patch data obtained by visual interpretation of high-definition remote sensing images, combined with field investigations, this paper explores the temporal and spatial evolution characteristics of the settlement system in Nagqu County, northern Tibet, summarizing its development status and existing problems from the perspective of factor-structure-function, and details the paths for rural revitalization on this basis. The results show the following: (1) Since 2005, the settlement system of Nagqu County has undergone a phase transition from concentrated settlement to functional expansion, with the continuous enrichment of development elements and the enhancement of functions. The density distribution of settlements shows strong adaptability to the natural geographical environment. The pattern of settlement has gradually changed from resource-dependent to facility-dependent. Transportation and public service facilities play an important role in guiding the speed and direction of settlement evolution. (2) There are still various problems in the settlement system of Nagqu County, including a weak industrial foundation; some occupation of important ecological spaces and ecologically fragile areas by settlements; insufficient attention to the cultural aspect of the Tibetan settlement system; a scattered settlement layout, which makes grassroots governance difficult; a large talent gap; and weak spatial support system of settlements. (3) From the perspective of enriching and integrating the development factors of rural settlements, reorganizing the diversified structure of rural settlements, and improving and expanding the functions of rural settlements, this paper explains the correlation mechanism between optimization of the rural settlement system and rural revitalization, and puts forward the implementation paths for rural revitalization in alpine pastoral areas of the QTP. The study expands our understanding of the characteristics of settlements in sparsely populated alpine pastoral areas, and provides valuable, up-to-date policy guidance for the promotion of rural revitalization in alpine pastoral areas on the QTP. [ABSTRACT FROM AUTHOR]

Background. The prevalence of chronic kidney disease (CKD) at high altitude is not known. We conducted a population-based survey in Tibet to identify the prevalence and associated risk factors of CKD in subjects living at altitudes of > 3500 m.Methods. One thousand two hundred and eighty-nine Tibetans (≥ 18 years) from four districts of Lhasa city (altitude 3658 m) and eight villages of Dangxiong County (altitude 4200 m) were interviewed and tested for haematuria, albuminuria and estimated glomerular filtration rate (eGFR).Results. The adjusted prevalence of hypertension, albuminuria, haematuria and reduced eGFR were 38.8% (95% CI: 36.2–41.5%), 16.2% (95% CI: 14.1–18.2%), 3.9% (95% CI: 2.8–4.9%) and 2.1% (95% CI: 1.3–2.9%), respectively. Both the presence of hypertension and the presence of albuminuria were strongly and independently associated with hyperuricaemia and elevated haematocrit.Conclusions. This is the first population-based epidemiological study of CKD in the Tibetan population. We found a higher prevalence of CKD and associated high prevalence of albuminuria, hypertension, hyperuricaemia and high haematocrit in the Tibetan population. The present study indicates the urgent need to develop comprehensive strategies targeted at reducing the CKD burden in this area and may lead to a better understanding of CKD in high-altitude populations. [ABSTRACT FROM AUTHOR]

The Rutog granitic pluton lies in the Gangdese magmatic arc in the westernmost part of the Lhasa Terrane, NW Tibet, and has SHRIMP zircon U-Pb ages of c. 80 Ma. The pluton consists of granodiorite and monzogranite with SiO[sub2] ranging from 62 to 72 wt % and Al2 03 from 15 to 17 wt%. The rocks contain 2.33-4.93 wt% K[sub2]O and 3.42-5.52 wt% Na[sub2]O and have Na[sub2]O/K[sub2]O ratios of 0.74-2.00. Their chondrite-normalized rare earth element (REE) patterns are enriched in LREE ((La/Yb)n = 15 to 26) and do not show significant Eu anomalies (SEu = 0.68-1.15). On a primitive mantle-normalized trace element diagram, the rocks are rich in large ion lithophile elements (LILE) and poor in high field strength elements (HFSE), HREE and Y. Their Sr/Y ratios range from 15 to 78 with an average of 30. The rocks have constant initial [sup87]Sr/[sup86]Sr ratios (0.7045 to 0.7049) and slightly positive ϵ[subNd](t) values (+0.1 to +2.3), similar to I-type granites generated in an arc setting. The geochemistry of the Rutog pluton is best explained by partial melting of a thickened continental crust, triggered by underplating of basaltic magmas in a mantle wedge. The formation of the Rutog pluton suggests fiat subduction of the Neo-Tethyan oceanic lithosphere from the south. Crustal thickening may have occurred in the Late Cretaceous prior to the India-Asia collision. [ABSTRACT FROM AUTHOR]

Abstract: The 2008 Mw 7.9 Wenchuan earthquake is a consequence of ongoing India-Tibet collision and reflects the growth of the Longmen Shan fold-and-thrust belt. In this paper, we present new constraints on the deformation mechanism of the Longmen Shan fold-and-thrust belt, by comparing the physical models to the example of the Longmen Shan fold-and-thrust belt. The result indicates that the deformation mechanism of the belt is mainly dominated by the pre-Sinian layer, whereas locally is controlled by the Lower Triassic layer, such as the Longquan anticline. In addition, we discuss the deformation style of the Longquan anticline various along strike, based on the seismic reflection data, interpretations of structural cross-sections and field observations, as well as physical modeling. The sandbox modeling suggests that the deformation of the central segment of Longquan anticline is likely controlled by higher displacement rate, higher erosion and lower sedimentation, which is in contrast with the southern and northern segment. Moreover, the structural geometry of the central segment of Longquan anticline is more complex than the end-member models of fault-related folds, which is mainly controlled by pure-shear wedge fault-bend fold and bounded by west-verging thrust fault. Combining the studies of the structural geometry, deformation mechanism, and previous studies, we infer that the Longquan anticline is active and potentially seismogenic. Therefore, a quantitative re-evaluation of seismic hazard in Longquan anticline and adjacent area directly beneath the densely populated Sichuan basin is urgently needed. [Copyright &y& Elsevier]