摘要：
Iron formations are valuable archives of sedimentary conditions and post-depositional events.However,geochemical proxies commonly used to determine genetic characteristics can be variably modified during metamorphism and deformation,hampering their use as records of regional geological events.This work focuses on strongly reworked magnetite-quartz-rich rocks from the S?o Josédo Campestre Massif,one of the oldest fragments of preserved crust in South America.The genetic classification of these magnetite-quartz-rich rocks is not straightforward because primary assemblages and textures were variably modified by granulite facies metamorphism during a regional Paleoproterozoic migmatization event.To address genetic ambiguities,we analyzed their magnetite and pyroxene chemistry,wholerock geochemistry,and Sm-Nd isotopes.Magnetite chemistry indicates that pyroxene-poor iron formations(Type B)are low in trace elements such as Ti,Al,V,and Mn,suggesting a chemical similarity to iron formations elsewhere.In contrast,magnetites from pyroxene-enriched Type A iron formations are rich in trace elements and more akin to magnetite crystallized from higher temperature systems,such as skarn and IOCG.The^(147)Sm/^(144)Nd of these rocks show substantial variation even at the outcrop scale,indicating a locally-controlled,highly heterogeneous mixture of Archean,Paleoproterozoic,and Neoproterozoic sources.Therefore,our geochemical tools point out to heterogenous signatures of these magnetitequartz rocks and proxies compatible with both low and high-temperature conditions and age of deposition spanning sources from the Archean to the Neoproterozoic.We interpret that the studied S?o Josédo Campestre magnetite-quartz rocks represent Archean iron formations with original magnetite chemistry and isotopic signatures variably modified by metamorphism and by at least one deformation-related hydrothermal event.These results contrast with similar examples from China and Greenland where iron formations either preserved the magnetite chemistry or the primary isotopic signatures.Our study indicates that metamorphism can selectively affect chemical proxies used to study iron formations and undermine the genetic classification of iron ores.Thus,these proxies should be carefully applied in the interpretation of syn-depositional environments of polydeformed belts.
摘要：
The"corridor"constructed jointly by multi-nationalities provides a space of cultural dissemination for the Legend of King Yu Tamed the Flood the in Hexi Corridor.Legend of King Yu Tamed the Flood spreads on the flowing cultural"corridor",relying on various narrative forms of cultural media.It deeply promotes the localization of the Legend of King Yu Tamed the Flood.The situation of integration and harmony between ethnic groups and Common value orientation of multi-ethnic humanities and religions are explored and taken through the multicultural elements embedded in the legend so that the"cultural integration"hidden in the legends and stories can emerge.
摘要：
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摘要：
本發(fā)明涉及獸醫(yī)生物技術(shù)領(lǐng)域，尤其涉及一種豬輪狀病毒重組蛋白以及表達該蛋白的重組腺病毒和應(yīng)用。所述所述重組蛋白由豬輪狀病毒5型VP7蛋白和豬輪狀病毒9型VP8蛋白連接組成，具體包括如SEQ ID NO:1所示的氨基酸序列。本發(fā)明將豬輪狀病毒5型VP7蛋白和豬輪狀病毒9型VP8蛋白的編碼基因的基因序列構(gòu)建至腺病毒表達載體中，并進行密碼子優(yōu)化，制備得到針對豬輪狀病毒的重組腺病毒，該重組腺病毒表達的目的蛋白的結(jié)構(gòu)和功能與天然狀態(tài)完全一致，具有較高的安全性和免疫原性。
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