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The uplift of the Tibetan Plateau significantly affected the global climate system. However, the timing of its uplift and the formation of its vast expanse are poorly understood. The occurrence of two types of leucogranites (the two-mica leucogranites and garnet-bearing leucogranites) identified in the Ailaoshan-Red River (ASRR) shear zone suggests an extension event in the southeastern Tibetan Plateau. The age of these leucogranites could be used to constrain the timing of uplift and southeastward expansion of the plateau. Petrography, geochronology and geochemistry investigations, including Sr–Nd isotope analysis, were conducted on the two-mica leucogranites and garnet-bearing leucogranites from the ASRR shear zone. LA-ICP-MS zircon U–Pb dating indicates that these rocks were emplaced at ~27 ​Ma, implying that the Tibetan Plateau had already achieved maximum uplift prior to the late Oligocene. It subsequently started to expand southeastward as a result of crustal flow. Compared to classic metapelite-derived leucogranites from Himalaya, the two-mica leucogranites show high K2O/Na2O (1.31–1.92), low Rb/Sr, CaO, lower 87Sr/86Sr ratios (0.7089–0.7164) and higher εNd(t) (−8.83 to −3.10). This whole-rock geochemical characteristics likely indicates a mixing source origin, composed predominantly of amphibolite with subordinated metapelite, which is also evidenced by 87Sr/86Sr vs. εNd(t) diagram. However, The garnet-bearing leucogranites with high SiO2 contents (72.25–74.12 ​wt.%) have high initial 87Sr/86Sr ratios (0.7332–0.7535) and low εNd(t) (−16.36 to −18.98), indicating that they are derived from the source comprised of metapelite and results of fluexed muscovite melting under lower crustal level, which is also evidenced by the Rb–Sr–Ba systematics. These leucogranites formed from partial melting of the thickened lower crust, which resulted in the formation of granitic melt that weakened the crust. The weakened crust aided the left-lateral strike-slip movement of the ASRR shear zone, triggering the escape of the Indochina terrane in the southeastern Tibetan Plateau during the late Oligocene. Keywords: Leucogranites, Crustal flow, Southeastward expansion, Ailaoshan-red river shear zone, Tibetan plateau

Molybdenum disulfide (MoS2) was synthesized via hydrothermal process under the assistance of citric acid, which exhibited high photocatalytic property in the application of methylene blue (MB) degradation. The flower ball microstructure of MoS2 changed with different amounts of citric acid. X-ray diffraction (XRD), Scanning electron microscope (SEM), UV-Vis diffuse reflectance spectra have been employed to characterize the samples. It improved the photocatalytic efficiency nearly 19.77% compared to MoS2 without citric acid. When H2O2 was added, the synergistic effect of MoS2 and hydrogen peroxide (H2O2) was observed in photocatalytic reaction system, which degraded MB completely within 40 min under visible light irradiation.

As a result of the evolution of Meso-Tethys, Early Cretaceous granitoids are widespread in the eastern Tengchong terrane, SW China, which is considered as the southern extension of the Tibetan Plateau. These igneous rocks are therefore very important for understanding the tectonic setting of Meso-Tethys and the formation of the Tibetan Plateau. In this paper, we present new zircon U-Pb dating, whole-rock elemental, and Nd isotopic data of granitoids obtained from the eastern Tengchong terrane. Our results show that these granitoids are composed of monzogranites and granodiorites and formed at ca. 124 Ma in the Early Cretaceous. Mineralogically and geochemically, these granitoids display metaluminous nature and affinity to I-type granites, which are derived from preexisting intracrustal igneous source rocks. The predominantly negative whole-rock εNd(t) values (−10.86 to −8.64) for all samples indicate that they are derived mainly from the partial melting of the Mesoproterozoic metabasic rocks in the lower crust. Integrating previous studies with the data presented in this contribution, we propose that the Early Cretaceous granitic rocks (135–110 Ma) also belong to I-type granites with minor high fractionation. Furthermore, in discriminant diagrams for source, granitoids are mainly derived from the partial melting of metaigneous rocks with minor sediments in the lower crust. The new identification of the Myitkyina Meso-Tethys ophiolitic suite in eastern Myanmar and mafic enclaves indicate that these Cretaceous igneous rocks were the products of the tectonic evolution of the Myitkyina Tethys Ocean, which was related to post-collisional slab rollback. Moreover, the Tengchong terrane is probably the southern extension of the South Qiangtang terrane.

This paper investigates the Jigede gabbros from the Shalazhashan tectonic belt, Alxa Block. Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) zircon U-Pb dating reveals that they were emplaced in the Middle Permian (ca. 262 Ma). All the gabbro samples collected from the intrusion exhibit low contents of TiO2 (0.24–0.37 wt %) and $${\text{F}}{{{\text{e}}}_{{\text{2}}}}{\text{O}}_{{\text{3}}}^{{\text{T}}}$$ (4.87–5.41 wt %), but high levels of MgO (11.15–12.15 wt %), CaO (11.45–12.75 wt %), Al2O3 (14.18–17.08 wt %) and high Mg# (0.81–0.83). Relative to HREEs and LILEs, the gabbros are enriched in LREEs and depleted in Th, Nb, Ce, Zr, Hf, and Ti, with positive Eu, Sr and U anomalies. In contrast to MORB, the Jigede intrusion has higher initial 87Sr/86Sr values of 0.7046 to 0.7054 and lower eNd(T) of + 1.8 to + 4.8. Elemental and isotopic data suggest that the intrusion was likely to have been produced by partial melting of a shallow lithospheric mantle source modified by slab-derived fluids, with subsequent cumulation of plagioclase. Thus, the Jigede intrusion was emplaced in a back-arc setting, in response to the Paleo-Asian oceanic subduction. In addition, the final closure of the Paleo-Asian Ocean did not occur prior to the Middle Permian.

The Early Cretaceous Houyaoyu granite porphyries are located in the south margin of the North China Craton. Field observations, petrography, geochronology, major and trace elemental and Sr-Nd isotopic compositions are reported to elucidate the genesis of the Houyaoyu granite porphyries. SIMS zircon U-Pb analyses for the Houyaoyu granite porphyries yield two concordant ages of 133.2±2.3 (2σ) and 131±1.1 (2σ) Ma, respectively. Major and trace elemental compositions indicate that these porphyries are high-K I-type granites with high contents of SiO2, K2O, Rb, U, Pb, low Nb, Ta, Ti, and P. Initial 87Sr/86Sr ratios range from 0.708 3 to 0.709 7, and eNd(t) values range from -9.13 to -12.3, with corresponding two-stage depleted-mantle Nd model ages (T2DM) varying from 1.57 to 1.91 Ga. This suggests that the Houyaoyu granite porphyries were predominantly derived from ancient lower continental crust, with minor involvement of mantle-derived components. On the basis of the tectonic evolution of the Qinling Orogen and geochemical characteristics of the Houyaoyu granite porphyries, it is proposed that they were formed in an extensional tectonic setting related to lithospheric destruction of the North China Craton, and produced Mo and Pb-Zn mineralization in East Qinling Orogen.

The I-S-A-type classification scheme for granites has been widely used to identify potential sources and the tectonic setting of granitic magmatism. Recent geochemical studies have shown that most granites are derived from a mixture of mantle and crustal sources, and that granitic magmatism contribute to generation and differentiation of the continental crust. However, the origin of granites with transitional affinities remains unclear, along with their role in the growth and differentiation of the continental crust. In this contribution, the ca. 91 Ma Bozhushan biotite granites in the southwestern Cathaysia Block, China, are characterized by high abundance of high-field-strength elements (HFSEs), with Zr + Nb + Ce + Y > 350 ppm and 10000*Ga/Al > 2.6, which are features typical of A-type granites. However, biotites in the Bozhushan granites are compositionally distinct from those of typical A- and S-type granites. Decreasing P2O5 contents with increasing SiO2 contents are consistent with an I-type rather than a S-type granite. Petrographic observations and geochemical data suggest that the Bozhushan granites have transitional I-A-type affinities. The Bozhushan granites contain remarkably evolved isotopic compositions, with eNd(t) = −9.2 to −8.0 and eHf(T) = −9.8 to −7.3, which are slightly lower than values for Late Cretaceous Baiyunshan alkaline igneous rocks. The Bozhushan granites have the low Y/Nb and Yb/Ta ratios, which are similar to the Baiyunshan alkaline igneous rocks, and continental alkaline basalts from the East African Rift and eastern China, ocean island basalts, and A1-type granitoids. Geochemical data indicate that the Bozhushan granites were likely generated by high-temperature melting of a hybrid source containing underplated alkaline igneous rocks and Precambrian basement rocks. Although the Bozhushan granites have crustal isotopic compositions, our data indicate that these granites also represent the formation of new crust. Thus, granites with transitional I-A-type affinities, such as the Bozhushan granite, have a role in the generation of continental crust.

Identifying alteration minerals of porphyry Cu deposits by using multispectral remote sensing data is a significant approach for ore prospecting. However, obtaining refined alteration information related to a porphyry Cu system is still challenging, especially in an area with complex geological background. In this study, the effectiveness of spectroscopic techniques for mapping alteration minerals associated with the Pulang porphyry copper deposit, SW China, which is located in high altitude and with tough terrain, were discussed by using ASTER and WorldView-3 data. The method of Principal Component Analysis (PCA) + Spectrum-Area (S-A) was developed to enhance the remote sensing information extraction of the alteration zones with quartz, sericite, chlorite and epidote. The results suggested that the extraction accuracy of porphyry alteration minerals based on WorldView-3 data with the method of PCA + S-A is significantly improved comparing with that of ASTER data. Using the method, we identified a new alteration zone caused by sericite anomalies in the Pulang deposit, which was afterward confirmed by field investigation. Hence, the PCA + S-A method based on WorldView-3 data is an effective approach for mapping alteration zones and ore prospecting in the porphyry copper system.

Molybdenum disulfide (MoS₂) was synthesized via hydrothermal process under the assistance of citric acid, which exhibited high photocatalytic property in the application of methylene blue (MB) degradation. The flower ball microstructure of MoS₂ changed with different amounts of citric acid. X-ray diffraction (XRD), Scanning electron microscope (SEM), UV-Vis diffuse reflectance spectra have been employed to characterize the samples. It improved the photocatalytic efficiency nearly 19.77% compared to MoS₂ without citric acid. When H₂O₂ was added, the synergistic effect of MoS₂ and hydrogen peroxide (H₂O₂) was observed in photocatalytic reaction system, which degraded MB completely within 40 min under visible light irradiation.

The Gejiu Sn ore district, one of the largest Sn producing area (300Mt @1 wt% Sn) in the world, is located in the western margin of the Cathaysia Block, SW China. There are five types of Sn ores in the Gejiu district, including greisen, skarn, veined tourmaline, massive sulfide and oxidized. Among these types of Sn ores, the genesis of the oxidized Sn ores is most controversial, such as magmatic hydrothermal origin and sedimentary exhalative (SEDEX) or hot water deposition (Red Sea type). This paper reports U-Pb ages, fluid inclusions, trace elements and H-O isotopes of cassiterite from the oxidized Sn ores, aiming to solve this issue. LA-MC-ICPMS cassiterite U-Pb dating yielded an age of 86.7 ± 2.8 Ma, which is accordant with the formation ages (~86 Ma) of granitic intrusions in the Gejiu district. Two types of fluid inclusions in cassiterite from the oxidized Sn ores were observed, one type is CO2-rich inclusions (Type 1) and the other type is aqueous inclusions (Type 2). The homogenization temperatures range from 220 to 366 °C and the salinities range from 10.9 to 21 wt% NaCl equiv. for the two types of fluid inclusions. Furthermore, fluid inclusions in cassiterite from the oxidized Sn ores located at 300 m far away from granitic intrusions have higher temperatures (357–366 °C) than those located at 500 m (273–330 °C). Hence, the ore-forming temperatures tend to decrease with the distance far away from the magmatic hydrothermal center. The vapor components for the two types of fluid inclusions are CO2 and H2O, respectively, and the liquid phase compositions of them are all H2O. The CO2 in the ore-forming fluids may source from marble by decarbonization. This indicates that the precipitation of cassiterite is resulted from fluid immiscible. The δ18O values of fluid inclusions in cassiterite range from +6.1 to +7.7‰, and the δD values range from −135 to −153‰, indicating a mixture of magmatic and meteoric waters. Trace elements show that cassiterite is rich in In, Rb and U, but Ba, Nb and Ti are depleted. In addition, the lower Sr (0.4–2.1 ppm) and higher Sc (35.9–53.7 ppm) contents reflect that the formation of cassiterite is related to F-rich intermediate-acid magma. Cassiterite has a relatively low total REE contents (2.7–9.2 ppm) with negative Eu (δEu = 0.14–0.76) and Ce (δCe = 0.1–0.6) anomalies, indicating that the ore-forming environment is oxidized. This is consistent with the cassiterite precipitation conditions. Hence, all the evidence supports that the oxidized Sn ores are genetically associated with the Gejiu granitic magmatism.

The Early Palaeozoic Shuanggou ophiolite is the best-preserved part of the Ailaoshan ophiolite belt. The microgabbros (basaltic dykes) and basalts (basaltic lavas) show distinct characteristics in geochemistry, implying that their genetic mechanisms are different. With Al2O3 contents ranging from 14.7% to 17.0%, the microgabbros belong to low-alumina type. They exhibit normal mid-ocean-ridge basalt (N-MORB) -like trace elemental characteristics with positive εNd(t) values (9.7–11.6) and slightly variable (87Sr/86Sr)i ratios (0.7036–0.7046). In contrast, the basalts have high Al2O3 contents (19.5–23.2%), therefore belonging to high-alumina type. A plagioclase-accumulation model is used to account for the high alumina contents. Moreover, the basalts have enriched MORB (E-MORB) -like trace element characteristics with lower εNd(t) values (6.4–8.0) and (87Sr/86Sr)i ratios (0.7032–0.7036). Their incompatible element ratios exhibit linear correlation with the isotopic data, which is probably related to the contribution of a mixed lithosphere–asthenosphere source. In summary, a two-stage model is proposed to explain the formation of the Shuanggou ophiolite: (1) at the continent–ocean transition stage, the basalts were generated by low-degree partial melting of the mixed mantle near a slow-spreading embryonic centre; and (2) at the mature stage of the Ailaoshan Ocean, the microgabbros were produced by moderate-degree partial melting of the depleted asthenospheric mantle.

To explore the association of HLA-DM gene with childhood systemic lupus erythematosus (SLE).DMA and DMB genes were genotyped by sequence-based typing(SBT)in 79 SLE patients at our hospital from 2003 to 2006 and 57 normal controls.The frequency of DMB*0101/0102 was lower significantly in SLE patients than that in controls (5.1% vs 21.1%). And the frequency of DMB*0102/0102 in SLE patients with renal involvement was higher than that in controls (17.6% vs 1.8%, P0.05). The frequency of all alleles and other genotypes had no significance in SLE patients, SLE patients with different organ involvements and controls.As a protective gene, DMB*0102/0102 may be a susceptible allele for SLE patients with renal involvement.

To investigate the serum leptin and adiponectin levels in nonalcoholic fatty liver disease (NAFLD) patients, and their relationship with insulin resistance.A total of 120 cases were enrolled and divided into two groups: NAFLD group (n = 60) and normal control group (n = 60). The serum levels of leptin and adiponectin were measured by ELISA. The body mass index (BMI), waist-to-hip ratio (WHR), triglyceride (TG), total cholesterol (Tchol), high-density lipoprotein cholesterol (HDL-C) , aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyl transpeptidase (GGT), fasting blood glucose (FBG) and HOMA-IR (homeostasis model assessment insulin resistance) were detected and analyzed.Compared with control group, the serum leptin level in NAFLD group was Significantly higher [(12.37+/-1.99) microg/L vs (5.20+/-1.03) microg/L, P less than 0.01], while the serum adiponectin level was significantly lower [(12.69+/-2.83) mg/L vs (22.83+/-4.61) mg/L, P less than 0.01]. HOMA-IR was also much higher in NAFLD group than that in control group[(4.86+/-0.63) vs (1.91+/-0.41), P less than 0.01]. Logistic regression analysis showed that leptin was positively correlated with WHR (beta value = 8.175, P less than 0.01), HOMA-IR (beta value = 0.974, P less than 0.01 ), FBG (beta value = 0.564, P less than 0.01 ). In contrast, adiponectin inversely associated with HOMA-IR (beta value = -0.495, P less than 0.01 ) and BMI (beta value = -0.314, P less than 0.01) respectively.The increased serum leptin level and decreased serum adiponectin level in NAFLD patients independently associated with HOMA-IR.

A divide-by-16/17 dual-modulus prescaler (DMP) and two programmable & plus swallow dividers for application in a digital video broadcasting-terrestrial (DVB-T) receiver are designed in a 0.18mum 3.3V mixed-signal CMOS process. The master/slave D-flip-flop (DFF) in the DMP is made up of an improved D-latch to increase the speed and the driving capability. A novel D-latch architecture integrated with 'OR' logic is proposed to decrease the complexity of the circuit. Post simulation results of the chip layout indicate that the proposed DMP works well at the frequency band of 1~2 GHz. The maximum operating speed is 2.4 GHz. The programmable & plus swallow dividers are directly synthesized by EDA tools and finally fabricated with 0.18 mum standard library.

To review and analyze the clinical features, treatment, and outcome of macrophage activation syndrome (MAS) in children with systemic onset juvennil rheumatoid arthritis (SOJRA).Retrospective review and analysis were performed on cases with MAS from a prospectively collected database of children with SOJRA from the year of 2003 to 2006 in the Hospital.Twenty four patients (21 boys, 3 girls) were diagnosed as having MAS with SOJRA. Mean age of the patients with MAS at diagnosis was 7 years, and the duration prior to diagnosis of MAS was 12 months. No trigger factors were found except in one case whose MAS was triggered by use of methotrexate and in another by parvovirus B19 infection. High grade fever, new onset hepatosplenomegaly and lymphadenopathy, pancytopenia, liver dysfunction were common clinical features in all the 24 cases (100%). Bleeding from skin, mucous membrane and gastrointestinal tract were noted in 9 cases (38%). Twelve (50%) cases had CNS dysfunction (high intracranial pressure, seizure and coma). Six cases (25%) developed ARDS. One patient suffered from renal damage. The laboratory test revealed elevated live enzymes and ferritin, decreased value of ESR, albumin, complete blood count and fibrinogen in all the 24 cases. Bone marrow examination supported the diagnosis of definite hemophagocytosis in the 24 cases. Lymph node biopsy was done for one case and histopathological examination showed that the node was full of activated macrophage. As to treatment, five cases only received high dose steroids (three of them died), 14 cases were treated with high dose steroids plus cyclosporine (one died), two were treated with steroids plus cyclosporine and etoposide (none died). The causes of deaths were ARDS and CNS involvement. In three of the cases who died, treatment was given up by their parents.MAS is a rare and potentially fatal complication of SOJRA. Most of our patients were male. Bone marrow studies support the diagnosis. CNS involvement and ARDS were poor prognostic signs. Early diagnosis and aggressive therapy are essential.

Development of systemic lupus erythematosus (SLE) is not only associated with single loci of HLA gene, but also possibly related to certain haplotypes and genotypes of MHC. In the present study the authors explored association of HLA-A, B, DR haplotype and genotype with SLE in Chinese children, analyzed a large family with multiple SLE patients and genetic origin of SLE patients with HLA-DRB1 * 15, to discover the influence of linkage disequilibrium of HLA gene on SLE.HLA-A, B, DR alleles were tested in 53 patients with SLE and 40 cases with their parents, 35 patients with SLE and HLA-DRB * 15 positive and 27 cases with their parents, a large family with SLE (18 members of three generations) and also 78 normal controls and 43 cases with their parents by microlymphocytotoxicity test and polymerase chain reaction - sequence specific primers (PCR-SSP). HLA-A, B, DR haplotype and genotype of SLE patients and controls were statistically calculated. The SLE patients with HLA-DRB1 * 15 and controls were analyzed for either the gene originated from the paternal or the maternal side.The variety of the haplotype in patient group (64/80) was less than that in control group (74/86). Only 9 haplotypes were found common between the patient group and control group. The frequency of the haplotype HLA-A9B40DRB1 * 15 was significantly higher in patient group than that in control group (P0.05), RR was 10.726 0. Five members of the large family had haplotype A9B40DRB1 * 15, 2 of them were patients with SLE, 1 of them was positive for ANA and had Raynaud's phenomenon and 2 of them were normal. The rest of the family members were normal. The frequency of genotypes DRB1 * 09/DRB1 * 15 and DRB1 * 03/DRB1 * 15 in SLE group was significantly higher than that of control group (P0.05), RR was 7.772 7 and 14.272 7, respectively. The number of SLE children with gene HLA-DRB1 * 15 derived from their fathers was significantly higher than that of the children with the gene derived from the mothers.These findings suggested that haplotype HLA-A9B40DRB1 * 15 and genotypes HLA-DRB1 * 09/DRB1 * 15, HLA-DRB1 * 03/DRB1 * 15 were correlated with SLE. The predisposition of multiple loci seems to have an additive effect. The children with their gene HLA-DRB1 * 15 derived from their fathers might more easily suffer from SLE than those with the gene derived from their mothers, the underlying mechanism needs further studies.