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The Zhejiang–Fujian region, situated along the southeastern coast of China and in the eastern part of the Cathaysia Block, is characterized by large volumes of late Mesozoic granitoid volcanics. We present new zircon U–Pb ages, whole‐rock geochemistry, and Sr─Nd─Hf‐isotope data for 3 rhyolite porphyries from the Luoyang region (LY‐1, LY‐2, and LY‐3). We identify 2 magmatic events. In Stage 1 (146 Ma), rhyolite porphyry LY‐1 was produced by the partial melting of Proterozoic Mayuan Group amphibolites and metasediments. In Stage 2 (130–126 Ma), rhyolite porphyries LY‐2 and LY‐3 were generated by the continued melting of amphibolites but with only a minor contribution from metasedimentary rocks. The fractionation of plagioclase, biotite, titanite, and allanite (degree of fractionation 0.7–0.5) from an LY‐2 parent magma produced LY‐3. Our new data, together with other published data, indicate that minor volcanism, related to the initial northwestward subduction of the Paleo‐Pacific Plate beneath SE China, occurred in a continental arc setting in the Zhejiang–Fujian coastal region from 160 to 140 Ma but that the major period of volcanism took place from 140 to 120 Ma in a back‐arc setting and occurred because of rollback of the subducting slab. [ABSTRACT FROM AUTHOR]

The Tongcun deposit is a medium-sized porphyry Mo deposit in the eastern section of the Qin-Hang metallogenic belt, South China. Fluid inclusions and scanning electron microscope -cathodoluminescence (SEM-CL) of different generations of quartz from multi-stage veins were studied to reconstruct the evolution of the porphyry hydrothermal system at the Tongcun Mo deposit. Four stages of hydrothermal veins were recognized at Tongcun, including the early barren quartz vein, the main ore-stage quartz-molybdenite vein and quartz-polymetallic vein, and the late quartz-calcite (± pyrite) vein. SEM-CL imaging revealed that these veins were composed of at least four successive quartz generations (A, B, C and D) in which only the quartz B and C are in close association with Mo mineralization. Fluid inclusions from the Tongcun deposit can be classified into four types, namely three- or four-phase CO 2 -rich (C), two-phase vapor-rich (V), two-phase liquid-rich (L) and three-phase liquid-rich solid-bearing (S) type. The C type fluid inclusions were further divided into C1 subtype with higher carbonic proportion (50–70% vol%), C2 subtype with lower carbonic proportion (25–40% vol%) and molybdenite daughter mineral, and C3 subtype with lower carbonic proportion (25–40% vol%) but no daughter mineral. The V type fluid inclusions were further divided into V1 subtype with higher filling degree (0.2 to 0.3) and V2 subtype with lower filling degree (< 0.1). The C1 and V1 subtypes were secondary inclusions in quartz phenocrysts (P) and primary inclusions in quartz A, and show homogenization temperatures (Th) of 257–378 °C, with salinities of 0.6–9.6 wt% NaCl equivalent. The immiscibility assemblage of coexisting C2 and V2 subtype inclusions in quartz B exhibit a Th of 237–285 °C and salinities of 1.2–4.4 wt% NaCl equivalent. C3 subtype inclusions in quartz C display Th of 191–267 °C and salinities of 0.2–4.6 wt% NaCl equivalent. Finally, the L and S type inclusions in quartz D display Th of 133–245 °C and salinities of 0.4–7.0 wt% NaCl equivalent. The fluid immiscibility is restricted in quartz B and only generated low salinity end member inclusions, similar to the immiscible behavior commonly observed in orogenic gold deposits. The likely molybdenite daughter minerals were only observed in C2 subtype inclusions in quartz B, indicating enrichment of Mo had occurred during fluid immiscibility. Combined with SEM-CL texture and Raman analysis, we proposed that a rapid Mo precipitation occurred in the narrow interval during or immediately after fluid immiscibility and thus formed the Tongcun Mo deposit. The CO 2 -rich ore-forming fluid and continental arc setting of the Tongcun deposit provide a special case of CO 2 -rich porphyry Mo system in non-collision settings. [ABSTRACT FROM AUTHOR]

The Shizitou deposit is a middle-sized Mo deposit in the Qin-Hang metallogenic belt, South China. Three stages of mineralization are recognized at the Shizitou, including the early stage characterized by barren quartz veins with potassic alteration, followed by the main ore stage represented by quartz-molybdenite veins with strong phyllic alteration, and the late stage featured by quartz-pyrite veins with weak propylitization. Two-phase liquid-rich aqueous (type I), two-phase gas-rich aqueous (type II), and halite-bearing (type III) inclusions are present in the main ore stage veins, but only type I inclusions occur in the early and late stages of veins. Type I inclusions in the early stage veins show homogenization temperatures (Th) of 291–376 °C, with salinities of 2.2–9.5 wt.% NaCl equivalent. Type II and III inclusions in the main ore stage veins display Th of 266–351 °C and 245–336 °C, and salinities of 0.6–3.5 and 28.0–36.2 wt.% NaCl equivalent, respectively. Type I inclusions in the late stage quartz-pyrite veins have Th of 209–288 °C and salinities of 0.5–5.0 wt.% NaCl equivalent. Fluid boiling took place in the main ore stage and promoted the quick precipitation of molybdenite from ore-forming solutions. Raman analysis of fluid inclusions implies that mineralizing fluids contain little CO 2 and N 2 . Hydrogen and oxygen isotopes indicate that initial ore-forming fluids were magmatic in origin and shifted gradually to meteoric regime. Re Os dating of molybdenite gives a 187 Re/ 187 Os isochron age of 162.3 ± 2.4 Ma, in response to a localized extensional setting resulting from the far-field stresses of the initial subduction of the Paleo-Pacific plate beneath the margins of the South China Block. [ABSTRACT FROM AUTHOR]

Objective: To establish a novel improved loop-mediated isothermal amplification (LAMP) technique to detect hepatitis A virus (HAV)., Methods: A novel improved LAMP assay based on the addition of an acceleration primer was developed for hepatitis A virus nucleotide acid detection., Results: Precision and reproducibility analysis proved its high stability and reliability. Comparison between the improved and conventional LAMP assays revealed that the former was more sensitive with a detection limit of 5 TCID50/ml. The novel detection method displayed 100% consistency with the TaqMan real-time PCR assay when applied to clinical specimens collected from patients with confirmed acute HAV infection., Conclusion: This novel technique is widely applicable as a simple diagnostic tool in the clinical field as well as for the surveillance and investigation of the infectious disease in developing countries where HAV is endemic.

Objective: To investigate the seroprevalence of hepatitis D virus in Foshan of Guangdong province, to provide the data for the study about it in China., Methods: ELISA kits from two different companies were used for detecting anti-HDV IgG of all the serum samples, and then RT-PCR was carried out about the selected serum to ensure the results. All the serum samples were collected in 2011 in The First People's Hospital of Foshan., Results: The results from two ELISA kits and RT-PCR were identical. Eight samples were positive., Conclusions: The seroprevalence rate of HDV in Foshan is higher than that in China. It has no statistically significant difference between female and male. Morever, the older with HBsAg are susceptible to HDV.

Objective: To study the effect of gene optimization on the expression and purification of HDV small antigen produced by genetic engineering., Methods: Based on the colon preference of E. coli, the HDV small antigen original gene from GenBank was optimized. Both the original gene and the optimized gene expressed in prokaryotic cells, SDS-PAGE was made to analyze the protein expression yield and to decide which protein expression style was more proportion than the other. Furthermore, two antigens were purified by chromatography in order to compare the purity by SDS-PAGE and Image Lab software., Results: SDS-PAGE indicated that the molecular weight of target proteins from two groups were the same as we expected. Gene optimization resulted in the higher yield and it could make the product more soluble. After chromatography, the purity of target protein from optimized gene was up to 96.3%, obviously purer than that from original gene., Conclusion: Gene optimization could increase the protein expression yield and solubility of genetic engineering HDV small antigen. In addition, the product from the optimized gene group was easier to be purified for diagnosis usage.

Objective: To prepare HDAg with biological activities as a candidate of diagnostic reagent., Methods: To synthesize HDV gene fragment after codon optimization. To construct a thio-fused recombinant plasmid based on M48 expression vector. To express in E. coli induced by IPTG. To purify the protein by affinity chromatography followed by characterization in ELISA:, Results: Plasmid construction was verified by enzyme digestion. SDS-PAGE indicated the molecular weight of the protein was the same as we expectation. ELISA proved its affinity with HDV antibodies., Conclusion: HDAg was obtained successfully and it will pave the road to the research of HDV diagnostic reagent.

FeS2 belongs to sulfide, including pyrite of isometric system and marcasite of orthorhombic system. The FeS2 discovered in Gengzhuang, Shanxi Province, was growing in the form of whisker. The study with scanning electron microscopy and electron probe show that the mineral components of FeS2 vary regularly. The structure of natural nano-micron FeS2 whisker was determined by micro-Raman spectroscopy. The results show that there exist two types of structure in FeS2 whiskers: pyrite and marcasite. Marcasite presents irregular shapes, such as coarse lotus root joints, crude columnar or beaded. Pyrite exists in the shape of straight line and smooth surface. In the early growing stage, Gengzhuang FeS2 whisker was mainly marcasite-type structure; in the middle stage it was coexistent structure of pyrite- and marcasite-type; in the late stage it was mainly pyrite-type. The growing stages of the whisker FeS2 show the phase transformation laws. Moreover, during the growing process marcasite was growing with pyrite coated on. Study on FeS2 whisker structure shows that there are correlations between phase transformation laws of the structure and forms, and between the forming time and the composition characteristics.