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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 Bayan Obo deposit in North China is famous for its enormous rare-earth element (REE) resources in the world. The carbonatite dykes occurring around the orebodies are considered to be closely related to the REE mineralization. Here we present new geochemical and C O isotopic data of the 'Wu' carbonatite dyke, together with integrated studies of fluid inclusion preserved in the quartzite spatially associated with the dyke and Rb Sr dating to reveal the dyke genesis and metallogenic process. The dyke has a geochemical signature and C isotopic composition similar to those of typical magmatic carbonatite, suggesting an igneous origin. It is also characterized by significant enrichment in REEs with extreme differentiation between light and heavy REEs, and negative Sr, Zr, and Ti anomalies, indicating that the magma evolved through fractional crystallization. The quartzite surrounding the dyke underwent strong fenitization. The types, microthermometric data and chemical compositions of the fluid inclusions suggest that the fluids preserved in the quartzite have great similarity with carbonatitic fluids, and Rb Sr dating of these fluid inclusions from the quartzite yielded an isochron age of 368 ± 43 Ma, indicating that there was an early Paleozoic activity of carbonatitic fluids caused by intrusion of the carbonatite dyke. During the early Paleozoic, the Bayan Obo deposit was under a subduction setting. The REE- and CO 2 -rich fluids/melts were released from subducted sediments during the subduction, and metasomatized and overprinted the pre-existing mineralization hosted in the dolomite, resulting in large-scale REE enrichment and mineralization. • The carbonatite dyke in the Bayan Obo deposit has a magmatic origin. • Fractional crystallization played a major role in the generation of the carbonatite dyke and lead to large REE enrichment. • The carbonatite dyke was intruded in Caledonian. • The Caledonian carbonatite had a contribution for REE mineralization in Bayan Obo. [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.