Our understanding of the assembly history of Asia depends critically on the tectonic relationships between its major cratons, including Siberia, North China, South China, and Tarim. The intervening microcontinents between these cratons can provide insight into the paleogeographic and paleotectonic relationships of the cratons, but there is currently a general lack of knowledge regarding the basement geology of these microcontinents. Here we present results from systematic geologic mapping, U-Pb zircon dating, whole-rock geochemical analysis, and synthesis of existing data to establish the Proterozoic to early Paleozoic evolution of the central Qilian basement to the south of the North China craton in northwest China. Our results indicate that the region underwent three major periods of magmatic activity at 960-880, 877-710, and 550-375 Ma. Our geochemical analysis suggests that the ca. 900 Ma plutons were generated during arc magmatism and/or syncollisional crustal melting, whereas the ca. 820 Ma plutons are A-type granitoids, which are typically associated with extensional tectonism. Igneous zircons from a high-and ultrahigh-pressure eclogite in the north-central Qilian Shan have a U-Pb age of ca. 916 Ma, whereas dating of the recrystallized rims suggests that eclogite facies metamorphism occurred at ca. 485 Ma. Our detrital zircon geochronology also indicates that a widespread metasedimentary unit in the region was deposited between ca. 1200 and ca. 960 Ma, prior to the onset of a rift-drift event at ca. 750 Ma. Based on regional geologic constraints and the magmatic history, we propose the following tectonic history: (1) the paleo-Qilian Ocean bound the combined North Tarim-North China craton to the south (present-day coordinates) in the Mesoproterozoic; (2) the paleo-Qilian Ocean closed between 900 and 820 Ma following the collision of North Tarim-North China craton and the South Tarim-Qaidam-Kunlun continent; (3) the younger Qilian Ocean opened at ca. 775 Ma along the previous suture trace of the paleo-Qilian Ocean as a marginal sea within southern Laurasia; and (4) this ocean closed by ca. 445-440 Ma as a result of collision between the Tarim-North China cratons and the Qaidam-Kunlun continent along a south-dipping subduction system.

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BackgroundDyslipidemia was present in most of the patients with coronary heart disease. Epidemiological evidence suggests that anthocyanin has some effects on the serum lipid. However, these results are controversial. This study aimed at collecting current clinical evidence and evaluating the effects of anthocyanin supplementation on total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) in dialysis patients.MethodsThe search included PubMed, Web of Science, MEDLINE, Cochrane Library, China National Knowledge Infrastructure, Wanfang Database (up to July 2015) to identify randomized controlled trials (RCTs) on the association between anthocyanin and serum lipids. RevMan (version 5.2) was used for Meta-analysis. Meta-regression analysis, sensitivity analysis and Egger’s weighted regression tests were performed by using STATA software (version 12.0; StatCorp, College Station, TX, USA).ResultsSix studies (seven arms) involving 586 subjects were included in this meta-analysis. The results showed that anthocyanin supplementation has significant effects on TC [MD = -24.06, 95% CI(-45.58 to -2.64) mg/dL, I2 = 93%], TG [MD = -26.14, 95%CI(-40.20 to -3.08) mg/dL, I2 = 66%1], LDL-C [MD = -22.10, 95% CI (-34.36 to -9.85) mg/dL, I2 = 61%], and HDL-C(MD = 5.58, 95% CI (1.02 to 10.14) mg/dL;I2 = 90%).ConclusionAnthocyanin supplementation significantly reduces serum TC, TG, and LDL-C levels in patients with dyslipidemia, and increases HDL-C. Further rigorously designed RCTs with larger sample sizes are needed to confirm the effectiveness of anthocyanin supplementation for dyslipidemia, especially hypo high density lipoprotein cholesterolemia.

Zircon U–Pb dating and whole-rock geochemical analysis have been performed on Late Jurassic – Early Cretaceous intrusive rocks of the Ulanhot area, NE China, with the aim of constraining the tectonic evolution of the central and southern Da Xingan Range. Zircon U–Pb dating indicates that Late Jurassic – Early Cretaceous magmatic events experienced four stages at: c. 155 Ma; c. 144 Ma; 135–130 Ma; and c. 126 Ma. The c. 155 Ma magmatic event consists of quartz diorite and granite-porphyryp with the geochemical characteristic of high Sr and Sr/Y or high A/CNK (1.38), implying the primary magma was derived from partial melting of a thickened lower crust which induced the closure of the Mongol–Okhotsk Ocean. The c. 144 Ma magmatic event consists of quartz monzodiorite with the geochemical characteristics of alkaline series, and indicates the delamination of a thickened crust. The 135–130 Ma magmatic event consists of syenogranite and granite-porphyry with characteristics of both I-type and A-type granites, which induced both the subduction of the Palaeo-Pacific oceanic plate and the post-orogenic extension of the Mongol–Okhotsk Orogenic Belt. The c. 126 Ma magmatic event consisted of highly fractionated I-type biotite granite and alkaline series gabbro, marking the end of the Mongol–Okhotsk Orogen, and implying that the study area was controlled by the circum-Pacific tectonic system during this stage.

The Eastern Kunlun Range in north Tibet, located along the northern margin of the eastern Tethyan orogenic system, records evidence for continental break‐up and ocean development in the Neoproterozoic, Paleozoic‐early Mesozoic subduction and continental collision, Mesozoic intracontinental extension, and Cenozoic contractional deformation. The Kunlun region is marked by active left‐lateral strike‐slip deformation of Kunlun fault system, one of the major intracontinental strike‐slip faults in Tibet that developed in response India‐Asia. To better constrain the tectonic evolution of the Eastern Kunlun Range and the closure of the various Kunlun oceans, we conducted detailed investigation integrating new geologic mapping, geochronology, and whole‐rock geochemistry with a synthesis of existing datasets across north Tibet. The Eastern Kunlun Range experienced three major deformation events in the Neoproterozoic, early Paleozoic, and Late Paleozoic‐early Mesozoic, which were associated with collision of the Proto‐, Paleo‐, and Neo‐Kunlun arcs, respectively. Our new detrital zircon analyses from Mesoproterozoic‐Cenozoic strata constrain stratigraphic age and sediment provenance and highlight the importance of three periods of arc activity. Our stratigraphic synthesis, including new field observations, provides new insights into connections between sediment dispersal and changes in tectonism and paleogeography. Miocene‐to‐present strike‐slip activity on the Kunlun fault and the associated strain pattern can be explained by clockwise rotation of the Kunlun fault and its wall rock as a bookshelf‐fault system, which has been proposed for northern Tibet as a result of distributed north‐south right‐lateral shear. The development of this fault system was facilitated by the presence of a Triassic suture that provided a preexisting weakness.