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| 1 | Variations of sulfur and carbon isotopes in seawater during the Doushantuo stage in late Neoproterozoic显示文摘Successive analyses of sulfur and carbon isotopic compositions of carbonates strata in the Doushantuo Formation in the Yangtze area were accomplished through a method of extracting trace sulfate from carbonates. Sulfur and carbon isotopic compositions of coeval seawater were estimated from the samples that show the least diagenetic alteration. A high-resolution age curve of sulfur isotopes in seawater sulfates was obtained in the Doushantuo stage, which reflects the trend of variation in seawater sulfur isotopes after the Neoproterozoic snowball Earth event. Similar characteristics of variation in carbon isotopes were observed in the coeval carbonates. A large positive d 34S excursion over +20?occurs in ancient seawater sulfates in the early Doushantuo stage. Simultaneously, the d 13C values in ancient seawater carbonates exhibit a positive excursion up to 10. The maximum d 34S and d 13C values are +46.4 and +6.9? respectively. In the middle Doushantuo stage, the range of variation in d 34S values of seawater is relatively narrow, but d 13C values are quite high. Then, d 34S values of seawater become oscillating, and the same occurs in d 13C values. Negative excursions in d 34S and d 13C values occur simultaneously at the end of the Doushantuo stage, and the minimum d 34S and d 13C values dropped down to -10.1 and -5.7? respectively. The characteristics of variations in the sulfur and carbon isotopes of ancient seawater imply strong changes in oceanic environment that became beneficial to inhabitation and propagation of organism. The organic productivity and burial rate of organic carbon once reached a quite high level during the Doushantuo stage. However, the state of environment became unstable after the global glaciation. The global climate and environment possibly were fluctuating and reiterating. The negative excursions in d 34S and d 13C values occurring at the end of the Doushantuo stage may represent a global event, which might be related to oxidation of deep seawater. | ZHANG Tonggang, CHU Xuelei, ZHANG Qirui, FENG Lianjun & HUO Weiguo Key Lab of Mineral Resources Exploration and Research, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China | 2003 | Chinese Science Bulletin2003，48，13： | 21 |
| 2 | Terminal Ediacaran anoxia in deep-ocean: Trace element evidence from cherts of the Liuchapo Formation, South China显示文摘Here we report a detailed trace element study of the cherts from Liuchapo Formation, which is a terminal Ediacaran (551-542 Ma) succession in South China deposited in deep-water basinal setting. The REE of Liuchapo cherts shows similar features as observed for anoxic modern seawater (but not for hydrothermal fluids), characterized by positive La anomaly (LaN/CeN = 0.83-1.91, average 1.37), moderately negative Ce anomaly (0.53-1.1, average 0.73), positive Gd anomaly (average 1.08), positive Y anomaly (average 1.21), and depleted LREE and MREE. In addition, the Liuchapo cherts have low ΣREE (3.36-56.13 ppm, average 20.6 ppm), low Al2O3, Ti, Th and Zr concentrations, and high Y/Ho ratios (up to 43.9). The redox-sensitive trace elements concentrations in the cherts do not correlate with detrital input proxies. All of these features suggest that the redox-sensitive trace elements in the cherts were authigenically concentrated in water column and their concentrations thus are excellent indicators of ancient redox conditions. Very low Th/U ratios, high V/(V+Ni) and FeT/Al ratios, enrichments of redox-sensitive trace elements (U, V, Mo), and low concentration of Mn in the cherts imply anoxia in the deep seawater. Our data reveal that the terminal Ediacaran ocean was not completely oxidized and the deep ocean was still anoxic, at least in South China. We propose that although the oxidative events existed in the terminal Ediacaran oceans, decomposition of organic matter prolonged anoxia in the deep ocean. | CHANG HuaJin CHU XueLei FENG LianJun HUANG Jing | 2009 | Science China Earth Sciences2009，52，6： | 16 |
| 3 | Carbon isotopic variations of Proterozoic carbonates in Jixian, Tianjin, China显示文摘Along the Proterozoic stratigraphic sections of Jixian, Tianjin, the ??13C values of carbonates are mostly negative in the Changchengian (Changcheng System), varying approximately within a range of (0±1)‰ in the Jixianian (Jixian System), and have commonly positive values of (2±2)‰ in the Qingbaikouan (Qingbaikou System). From Chuanlinggou Formation to Dahongyu Formation, i.e. from ca. 1700 Ma to 1600 Ma, the δ13C values of carbonates increase from about -3‰ to 0‰, but oscillate with large excursion in Dahongyu Formation. Two large excursions occur in the Jixianian, one in Yangzhuang Formation and the other in the third submember of Wumishan Formation overlaying. These integrated and continuous records of carbon isotope reflect secular variations of δ13C value in ancient seawater from ca. 1700 Ma to ca. 800 Ma. The increase and subsequent oscillation of seawater δ13C value occurring from the ages of ca. 1700 to ca. 1600 Ma and <1300 Ma may signify two correlative global tectonic events. | CHU Xuelei, ZHANG Tonggang, ZHANG Qirui, FENG Lianjun & ZHANG Fusong1. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China 2. Key Laboratory for Mineral Resources Research, Chinese Academy of Sciences, Beijing 100029, China Correspondence should be addressed to Chu Xuelei (email: xlchu@mail.c-geos.ac.cn) | 2004 | Science China Earth Sciences2004，47，2： | 13 |
| 4 | Discussion on the Neoproterozoic glaciations in the South China Block and their related paleolatitudes显示文摘The Kaigas, Sturtian, Marinoan, and Gaskiers glaciations are widely recognized in Neoproterozoic. However, in the South China Block only the Jiangkou (Sturtian) and Nantuo (Marinoan) are symbolized by sedimentary records. The Kaigas, recorded by isotopic and chemical proxies, exhibited likely the nature of cold paleoclimate with local mountain glaciation. The correlation of the Doushantuo Formation with the Gaskiers is indicated by the carbon isotope excursion and the dated age from the interval, however the South China Block was then under non-glacial weather. With no paleomagnetic data, the position of the South China Block during the Sturtian glaciation cannot be determined. The paleolatitudes of the South China Block during the Kaigas and Nantuo glaciations are intermediate, even though the Nantuo was once rendered erratically deduced equatorial. In fact, the paleolatitudes of the South China Block during the Neoproterozoic glaciations are all likely at about 30°―40°. | ZHANG QiRui CHU XueLei FENG LianJun | 2009 | Chinese Science Bulletin2009，54，10： | 9 |
| 5 | Phase I study of CAR-T cells with PD-1 and TCR disruption in mesothelin-positive solid tumors显示文摘Programmed cell death protein-1(PD-1)-mediated immunosuppression has been proposed to contribute to the limited clinical efficacy of chimeric antigen receptor T(CAR-T)cells in solid tumors.We generated PD-1 and T cell receptor(TCR)deficient mesothelin-specific CAR-T(MPTK-CAR-T)cells using CRISPR-Cas9 technology and evaluated them in a dose-escalation study.A total of 15 patients received one or more infusions of MPTK-CAR-T cells without prior lymphodepletion.No dose-limiting toxicity or unexpected adverse events were observed in any of the 15 patients.The best overall response was stable disease(2/15 patients).Circulating MPTK-CAR-T cells peaked at days 7–14 and became undetectable beyond 1 month.TCR-positive CAR-T cells rather than TCR-negative CAR-T cells were predominantly detected in effusion or peripheral blood from three patients after infusion.We further confirmed the reduced persistence of TCR-deficient CAR-T cells in animal models.Our results establish the preliminary feasibility and safety of CRISPR-engineered CAR-T cells with PD-1 disruption and suggest that the natural TCR plays an important role in the persistence of CAR-T cells when treating solid tumors. | Zhenguang Wang Na Li Kaichao Feng Meixia Chen Yan Zhang Yang Liu Qingming Yang Jing Nie Na Tang Xingying Zhang Chen Cheng Lianjun Shen Jiaping He Xun Ye Wei Cao Haoyi Wang Weidong Han | 2021 | Cellular & Molecular Immunology2021，18，9： | 7 |
| 6 | Iron speciation in cherts from the Laobao Formation,South China:Implications for anoxic and ferruginous deep-water conditions显示文摘Cherts in the Laobao Formation in the Silikou section,South China were deposited in terminal Ediacaran deep-water.The speciations of iron in cherts,such as pyrite Fe(FeP),HCl-extractable Fe(FeH),and total Fe(FeT),and their interrelationships,are proxies for distinguishing oxic,anoxic but ferruginous,and sulfidic conditions,which is an effective method for studying the terminal Ediacaran ocean environment.For chert samples from the Laobao Formation,pyrite concentrations are generally low(<0.56%),degree of pyritization(DOP)ranges from<0.01 to 0.78 and most are<0.45;(FeP+FeH)/FeT ratios are between 0.27 and 0.84 and most exceed 0.38,and most of FeT/Al ratios range from 0.55 to 5.87(averaging 1.1).Relatively high content of highly reactive Fe and low content of pyrite indicate a scarcity of H2S and Fe-enriched deep-water.These features suggested that the deposition setting of Laobao cherts was anoxic and ferruginous.Terminal Ediacaran deep-water in the South China Basin was most likely anoxic and ferruginous,which played a key role in the emergence and evolution of early multicellular life. | CHANG HuaJin CHU XueLei FENG LianJun HUANG Jing | 2010 | Chinese Science Bulletin2010，55，27： | 6 |
| 7 | The Pre-Sturtian Negative δ^(13)C Excursion of the Dajiangbian Formation Deposited on the Western Margin of Cathaysia Block in South China显示文摘The Dajiangbian Formation in South China is a siliciclastic-dominated sedimentary succession with low-grade metamorphism deposited on the western margin of the Cathaysia Block, and is capped by a glaciogenic diamictite(the Sizhoushan Formation). The Sizhoushan glaciogenic strata can be attributed to the Jiangkou glacial(Sturtian glacial) episode as they share stratigraphic and lithological similarities with Jiangkou strata in South China. Some carbonate, chert and shale units throughout the upper part of the Dajiangbian Formation were sampled for carbonate carbon isotope(δ^(13)C_(carb)) and organic carbon isotope(δ^(13)C_(org)) analyses. A range of geochemical indices including oxygen isotopes(δ^(18)O) and Mn/Sr(Fe/Sr) ratios suggest that primary carbon isotope values were preserved in the upper Dajiangbian Formation. The upper Dajiangbian Formation shows δ^(13)C_(carb) of-0.1‰, upward decreasing towards to-5.4‰. We suggest that the negative δ^(13)C excursion beneath the Sizhoushan diamictite is correlative with the Pre-Sturtian Islay δ^(13)C_(carb) anomaly and allows correlation with the global Neoproterozoic isotope stratigraphy. We find that carbonate and organic carbon isotope data of the upper Dajiangbian Formation are coupled, consistent with the δ^(13)C_(carb)-δ^(13)C_(org) pattern observed on multiple continents. | Lianjun Feng Qirui Zhang | 2016 | Journal of Earth Science2016，27，2： | 4 |
| 8 | Development of an innovative one-step nested PCR strategy for virus detection using the LNA technique显示文摘Dear Editor,Polymerase chain reaction(PCR)is a molecular diagnostic technique that has been widely used for diagnosing viral diseases.Nested PCR(N-PCR)is a variation on the standard PCR technique that involves two amplification steps,yielding greater sensitivity and specificity.But there are two main disadvantages:the protocol is more complex than conventional PCR,and the risk of cross-contamination is relatively high.One-step nested PCR(OSN-PCR)enables conventional N-PCR to be performed as a closed reaction in a single tube that contains both outer and inner primers.This strategy makes OSN-PCR more rapid than N-PCR,lowers the probability of cross-contamination,and requires a smaller amount of reagents. | Ji Wang Li Zhao Zhihua Sun Guixia Li Peihua Niu DANDi Li Lianjun Wang Yi Zhang Zhishan Feng Xuejun Ma | 2019 | Science China(Life Sciences)2019，62，3： | 4 |
| 9 | Stability analysis of robotic longitudinal-torsional composite ultrasonic milling显示文摘Currently,industrial robots are considered as an alternative towards traditional machine tools.Especially for the large-scale parts milling,robotic flexibility and low cost make it possess the irreplaceability.However,the milling chatter caused by its weak rigidity hampers robotic application and promotion severely in aviation industry.Rotary ultrasonic milling(RUM)technology with one-dimensional axial vibration has been proven and approved on avoiding robotic chatter.Based on this,the research of project team demonstrates that longitudinal-torsional composite ultrasonic milling(CUM-LT)involving separation characteristic has a greater advantage than RUM in terms of chatter suppression.Thereby,the CUM-LT as a new means is applied to avoid processing vibration of robotic milling system.And its influence mechanism on stability improvement of weak stiffness processing system is clarified.Meanwhile,the approaches to strengthen separation effect are provided innovatively.Moreover,a new analysis method of robotic CUM-LT(RCUM-LT)stability is proposed on the basis of ultrasonic function angles.The simulation and experimental results indicate that compared with robotic RUM(RRUM),stability regions of separated RCUM-LT(SRCUM-LT)and unseparated RCUM-LT(URCUM-LT)are improved by 124.42%and39.20%,respectively.The addition of torsional ultrasonic energy has a wonderful effect on the milling chatter suppression of low stiffness robots. | Lianjun SUN Wenhe LIAO Kan ZHENG Wei TIAN Jinshan LIU Jindan FENG | 2022 | Chinese Journal of Aeronautics2022，35，8： | 1 |
| 10 | Expression and subcellular localization of cysteine- and glycine-rich protein-2 in rat undifferentiated olfactory stem cells显示文摘BACKGROUND: As a member of the LIM protein family Ⅱ, cysteine- and glycine-rich protein-2 (CRP2) has been demonstrated to play a role in the regulation of growth and differentiation of eukaryotic cells. Our previous study has demonstrated that CRP2 can be detected in the embryonic rat inner ear but not in the adult rat inner ear. However, at present, the expression of LIM protein family Ⅱ members in stem or precursor cells has not been described. OBJECTIVE: To determine the expression and sub-cellular localization of CRP2 in olfactory stem cells. DESIGN, TIME AND SETTING: An experiment with repeated measures was performed in the Laboratory of Otorhinolaryngology, Head and Neck Surgery, Xijing Hospital, the Fourth Military Medical University from February 2008 to April 2008. MATERIALS: Olfactory stem cells, and rabbit-anti-CRP2 polyclonal antibody were prepared and kept in our laboratory. METHODS: Reverse transcription polymerase chain reaction and Western blot analysis were used to detect expression of CRP2 in olfactory stem cells. Immunocytochemistry was also used to localize CRP2 in olfac- tory stem cells. MAIN OUTCOME MEASURES: The expression and sub-cellular localization of CRP2 in rat olfactory stem cells. RESULTS: CRP2 expression was found in olfactory stem cells, and CRP2 was distributed in both the nu- cleus and the cytoplasm. CONCLUSION: Confirmation of the expression and distribution of CRP2 in olfactory stem cells. | Xue Gao Zengyu Cao Jun Chen Shunli Liu Dingjun Zha Feng Wang Yang Chen Li Qiao Lianjun Lu Jianhua Qiu | 2008 | Neural Regeneration Research2008，3，5： | 0 |
| 11 | Analysis on Tectonic Movement of the Longmenshan Fault Zone before the Wenchuan M_S 8. 0 Great Earthquake显示文摘On the basis of elastic rebound theory,using the horizontal velocity field of the Chinese mainland calculated from GPS data during three observation periods from 1999 to 2007,the velocity components that are parallel and plumb to the fault zone are calculated respectively for different periods,and then relative ground movements of two sides of the fault zone are analyzed with power function fitting and graphics. The results show that the relative ground movement shows right-lateral shear deformation before the Wenchuan MS8. 0 earthquake,and at the same time the movement was hindered by the Longmenshan fault zone. Thus,this result has positive significance for distinguishing the elastic strain energy accumulation and deformation anomaly in an earthquake preparation process,and for conducting further research on earthquake prediction. | Ping Jianjun Jiang Zaisen Feng Xiangdong Ping Caipeng Shan Lianjun Wang Xia | 2014 | Earthquake Research in China2014，28，3： | 0 |
| 12 | Hole surface strengthening mechanism and riveting fatigue life of CFRP/aluminum stacks in robotic rotary ultrasonic drilling显示文摘Carbon fiber reinforced plastic(CFRP)and aluminum stacks are widely used in aviation industry due to light weight and high performance.Millions of rivet holes need to be drilled on body materials,and more than 80%of fatigue cracks occur at the connection holes,so the damage and residual stress of hole surface have crucial effect on the riveting fatigue life of CFRP/aluminum stacks and the flight performance.Recently,robotic rotary ultrasonic drilling(RRUD)technology is a promising method to machine the stacks.However,the hole surface strengthening mechanism in RRUD and the service performance of the riveting joint are not verified.Thus,in this paper,the hole surface strengthening mechanism of RRUD for CFRP/aluminum stacks is investigated,a theoretical residual stress model is established,and the fatigue life experiment of riveted joints is conducted.Firstly,analysis on residual stress in RRUD is carried out with consideration of strengthening force and cutting temperature.Residual stress model is established based on the calculation of elastic stress,plastic stress and stress release.Validation experiment results show that ultrasonic vibration changes residual stress from tensile stress to compressive stress.At the same time,comparative damage analysis of CFRP hole exit and hole surface in robotic conventional drilling(RCD)and RRUD is presented.Finally,fatigue strength experiments of riveted joints are conducted for performance verification.Experimental results indicate that fatigue life of single-hole riveted joints is increased by 68%with ultrasonic vibration,and four-hole riveted joint arranged according to aerospace design standards is increased by more than 86%. | Song DONG Wenhe LIAO Kan ZHENG Feng XUE Lianjun SUN | 2023 | Chinese Journal of Aeronautics2023，36，10： | 0 |
| 13 | Genesis of Silica-phosphatic Nodules with Small Shelly Fossils Preserved in the Lowermost Cambrian of South China显示文摘Silica-phosphatic nodules are abundant in black shales of the Yanjiahe Formation in the Three Gorges Area of South China,which is correlated to the Fortunian Stage,Terreneuvian Series,Cambrian System.The nodules are rich in small shelly fossils and hence attract the attention of numerous paleontologists and sedimentary geologists.However,the genesis of the nodules and the preservation of the small shelly fossils are poorly understood.Here we analyze morphological,structural,mineralogical and chemical features of the nodules in multiscale using a combination of micro-X-ray fluorescence spectroscopy,X-ray diffraction,scanning electron microscopy and confocal laser Raman spectroscopy.Results reveal that nodules are concentric in chemical and mineralogical compositions,comprising a silica-phosphatic core encrusted sequentially by a phosphatic zone,a siliceous zone and a very thin pyrite outer rim.The black shales hosting the nodules demonstrate a laminated texture of alternating clayey and silty laminae,which were respectively deposited in sulfidic/less sulfidic,high/low production,intense/weak chemical weathering conditions.The phosphogenesis of the nodules resulted in the phosphatization of small shelly fossils,which prevented the fossils from being dissolved during diagenesis,whereas the silica encrustation sealed the fossils within the nodules and thus protected the fossils from alteration by deep burial and surface weathering. | QIU Hao FENG Lianjun CHU Xuelei LI Luoyang ZHANG Xingliang LI Jinhua | 2022 | Acta Geologica Sinica(English Edition)2022，96，4： | 0 |
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