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Pyrosequencing of nirS gene revealed spatial variation of denitrifying bacterial assemblages in response to wetland desertification at Tibet plateau

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Journal of Mountain Science 2019年第5期16卷 1121-1134页

作者： GU yun-fu LIU Ting BAI Yan xiang Quan-ju ZHANG Xiao-ping CHEN qiang Department of Microbiology College of Resource Science and Technology Sichuan Agricultural University

Amplicon sequencing of functional genes is a powerful technique to explore the diversity and abundance of microbes involved in biogeochemical processes. One such key process, denitrification, is of particular importance because it can transform nitrate(NO3-) to N2 gas that is released to the atmosphere. In nitrogen limited alpine wetlands, assessing bacterial denitrification under the stress of wetland desertification is fundamental to understand nutrients, especially nitrogen cycling in alpine wetlands, and thus imperative for the maintenance of healthy alpine wetland ecosystems. We applied amplicon sequencing of the nirS gene to analyze the response of denitrifying bacterial community to alpine wetland desertification in Zoige, China. Raw reads were processed for quality, translated with frameshift correction, and a total of 95,316 nirS gene sequences were used for rarefaction analysis, and 1011 OTUs were detected and used in downstream analysis. Compared to the pristine swamp soil, edaphic parameters including water content, organic carbon, total nitrogen, total phosphorous, available nitrogen, available phosphorous and potential denitrification rate were significantly decreased in the moderately degraded meadow soil and in severely degraded sandy soil. Diversity of the soil nirS-type denitrifying bacteria communities increased along the Zoige wetland desertification, and Proteobacteria and Chloroflexi were the dominant denitrifying bacterial species. Genus Cupriavidus(formerly Wautersia), Azoarcus, Azospira, Thiothrix, and Rhizobiales were significantly(P<0.05) depleted along the wetland desertification succession. Soil available phosphorous was the key determinant of the composition of the nirS gene containing denitrifying bacterial communities. The proportion of depleted taxa increased along the desertification of the Zoige wetland, suggesting that wetland desertification created specific physicochemical conditions that decreased the microhabitats for bacteria

关键词： Wetland desertification Amplicon sequencing nirS bacteria Differential abundance analysis

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Effect of axial static magnetic field on cleanliness and microstructure in magnetically controlled electroslag remelted bearing steel

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Journal of Iron and Steel Research International 2021年第12期28卷 1562-1573页

作者： qiang Li Zhi-bin Xia Yi-feng guo Zhe Shen Tian-xiang Zheng Biao Ding yun-bo Zhong School of Materials Science and Engineering State Key Laboratory of Advanced Special SteelShanghai Key Laboratory of Advanced FerrometallurgyShanghai UniversityShanghai200444China

The effect of the axial static magnetic field(ASMF)on cleanliness and microstructure in magnetically controlled electroslag remelted GCr15 bearing steel ingots was investigated *** results show that a magnetically controlled spin-vibration induced by the interaction of the ASMFs and the remelting current exists at the consumable electrode tip,resulting in thinner liquid melt film and smaller *** the increase in magnetic flux density,the optimization effect of ASMFs on electroslag remelting process increases and reaches the peak with a 40 mT ASMF,then *** cleanliness of the ingots was improved,and the count of inclusions larger than 5μm was *** microstructure of the ingots processed with a 40 mT ASMF was significantly *** depth of the metallic molten pool was reduced from 45.2 to 17.5 mm with the application of 40 mT *** tensile strength,impact toughness,and Rockwell hardness of the ingots obtained under the 40 mT ASMF were significantly *** mechanisms of the spin-vibration occurring at the electrode tip end were interpreted in detail to elucidate the effect of ASMFs.

关键词： Magnetically controlled electroslag remelting Axial static magnetic field Inclusion removal Molten pool Alternating Lorentz force Cleanliness GCr15 bearing steel

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Impact of oral anti-hepatitis B therapy on the survival of patients with hepatocellular carcinoma initially treated with chemoembolization

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Chinese Journal of Cancer 2015年第5期34卷 205-216页

作者： Zhong-guo Zhou Xing-Rong Zheng Qian Zhou Ming shi Yao-Jun Zhang Rong-ping guo yun-Fei Yuan Min-Shan Chen Xiao-Jun Lin xiang-Ming Lao Sheng-ping Li Department of Hepatobiliary Oncology Sun Yat-sen University Cancer CenterState Key Laboratory of Oncology in South China Collaborative Innovation Center for Cancer Medicine Department of Infectious Diseases The Third Affiliated Hospital of Sun Yat-sen University Epidemiology Research Unit Translational Medicine Research CenterThe First Affiliated Hospital of Sun Yat-sen University

Introduction:Most hepatocellular carcinomas(HCC) develop in a background of underlying liver disease including chronic hepatitis ***,the effect of antiviral therapy on the long-term outcome of patients with hepatitis B virus(HBV)-related HCC treated with chemoembolization is *** study aimed to evaluate the survival benefits of anti-HBV therapy after chemoembolization for patients with HBV-related ***:A total of 224 HCC patients who successfully underwent chemoembolization were identified,and their survival and other relevant clinical data were ***-Meier and Cox regression analyses were performed to validate possible effects of antiviral treatment on overall survival(OS).Results:The median survival time(MST) was 15.9(95%confidence interval[CI],9.5-27.7) months in the antiviral group and 9.6(95%CI,7.8-13.7) months in the non-antiviral group(log-rank test,P = 0.044).Cox multivariate analysis revealed that antiviral treatment was a prognostic factor for OS(P = 0.008).Additionally,a further analysis was based on the stratification of the TNM tumor *** the subgroup of early stages,MST was significantly longer in the antiviral-treatment group than in the non-antiviral group(61.8 months[95%CI,34.8 months to beyond the follow-up period]versus 26.2[95%CI,14.5-37.7]months,P= 0.012).Multivariate analysis identified antiviral treatment as a prognostic factor for OS in the early-stage subgroup(P = 0.006).However,in the subgroup of advanced stages,MST of the antiviral-treated group was comparable to that of the non-antiviral group(8.4[95%CI,5.2-13.5]months versus 7.4[95%CI,5.9-9.3]months,P = 0.219).Multivariate analysis did not indicate that antiviral treatment was a significant prognostic factor in this ***:Antiviral treatment is associated with prolonged OS time after chemoembolization for HCC,especially in patients with early-stage tumors.

关键词：抗病毒治疗原发性肝癌乙肝病毒生存期肝细胞癌乙型肝炎病毒多因素分析肿瘤患者

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Identification of reservoir types in deep carbonates based on mixedkernel machine learning using geophysical logging data

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Petroleum Science 2024年第3期21卷 1632-1648页

作者： Jin-Xiong shi xiang-Yuan Zhao Lian-Bo Zeng yun-Zhao Zhang Zheng-ping Zhu Shao-Qun Dong Key Laboratory of Exploration Technologies for Oil and Gas Resources of the Ministry of Education Yangtze UniversityWuhan4310HubeiChina School of Geosciences Yangtze UniversityWuhan430100HubeiChina College of Geosciences China University of Petroleum(Beijing)Beijing102249China Petroleum Exploration and Production Research Institute of SINOPEC Beijing100083China School of Earth Sciences and Engineering Xi'an Shiyou UniversityXi'an 710065ShaanxiChina

Identification of reservoir types in deep carbonates has always been a great challenge due to complex logging responses caused by the heterogeneous scale and distribution of storage *** cross-plot analysis and empirical formula methods for identifying reservoir types using geophysical logging data have high uncertainty and low efficiency,which cannot accurately reflect the nonlinear relationship between reservoir types and logging ***,the kernel Fisher discriminant analysis(KFD),a kernel-based machine learning technique,attracts attention in many fields because of its strong nonlinear processing ***,the overall performance of KFD model may be limited as a single kernel function cannot simultaneously extrapolate and interpolate well,especially for highly complex data *** address this issue,in this study,a mixed kernel Fisher discriminant analysis(MKFD)model was established and applied to identify reservoir types of the deep Sinian carbonates in central Sichuan Basin,*** MKFD model was trained and tested with 453 datasets from 7 coring wells,utilizing GR,CAL,DEN,AC,CNL and RT logs as input *** particle swarm optimization(PSO)was adopted for hyper-parameter optimization of MKFD *** evaluate the model performance,prediction results of MKFD were compared with those of basic-kernel based KFD,RF and SVM ***,the built MKFD model was applied in a blind well test,and a variable importance analysis was *** comparison and blind test results demonstrated that MKFD outperformed traditional KFD,RF and SVM in the identification of reservoir types,which provided higher accuracy and stronger *** MKFD can therefore be a reliable method for identifying reservoir types of deep carbonates.

关键词： Reservoir type identification Geophysical logging data Kernel Fisher discriminantanalysis Mixedkernel function Deep carbonates

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两层流体中大直径圆柱体的水动作用力

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上海交通大学学报 2005年第5期39卷 695-700页

作者：尤云祥石强缪国平上海交通大学船舶海洋与建筑工程学院上海200030

研究了两层流体中大直径垂直圆柱体上的水动力特性.基于分离变量法,建立了绕射势和辐射势的解析解,导出了作用在大直径圆柱体上水动作用力的计算公式.与单层流体不同,对两层流体,作用在大直径圆柱体上的水动作用力,除了表面波模态的波... 详细信息

研究了两层流体中大直径垂直圆柱体上的水动力特性.基于分离变量法,建立了绕射势和辐射势的解析解,导出了作用在大直径圆柱体上水动作用力的计算公式.与单层流体不同,对两层流体,作用在大直径圆柱体上的水动作用力,除了表面波模态的波浪力、附加质量和阻尼系数外,还有内波模态的波浪力、附加质量和阻尼系数.对所建立的求解模型进行数值计算分析的结果表明,在某个频率范围内,流体的分层效应对这些水动力量的影响是不可忽视的.

关键词：两层流体大直径圆柱体内波水动作用力

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Time-resolved ultra-small-angle X-ray scattering beamline(BL10U1)at SSRF

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Nuclear Science and Techniques 2024年第2期35卷 6-19页

作者： Wen-qiang Hua Chun-Ming Yang ping Zhou Feng Tian Jin-you Lin Yu-Zhu Wang Xiao-yun Li Xia-Ran miao Chun-Xia Hong Qiu-shi Huang Xin-Tong Zhao Yong-Feng Men Jie Wang Xing-Yu Gao Xiu-Hong Li Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China Key Laboratory of Advanced Micro Structural Materials MOEInstitute of Precision Optical EngineeringSchool of Physics Science and EngineeringTongji UniversityShanghai 200092China State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

The construction of a new beamline,BL10U1,was completed at the Shanghai synchrotron radiation facility in *** multipurpose beamline was designed to provide X-ray scattering techniques such as ultra-small-angle X-ray scattering(USAXS),small-angle X-ray scattering(SAXS),wide-angle X-ray scattering,and microfocus SAXS(μSAXS)for a broad user *** realize fast time-resolved USAXS experiments,the beamline adopted an in-vacuum undulator with a total length of 1.6 m as the photon *** in-house cryogenic-cooled double multilayer monochromator was installed to deliver a photon flux of approximately 10^(13) photons/s at a photon energy of 10 *** three-year successful operation of this beamline demonstrated that the monochromator operated smoothly,as ***10U1 has three end stations in succession:USAXS end station,μSAXS end station,and end station for industrial *** minimum scattering vector q~0.0042 nm^(-1) at 10 keV can be achieved at the USAXS end station equipped with a 28 m-long and 1.8 m-diameter vacuum flight *** theμSAXS end station,a beam spot of less than 10×8μm was achieved for micro-SAXS *** contrast,in situ experimental instruments up to 5 m high and 8 m wide can be mounted at the industrial application end station,which offers industrial scientists the opportunity to use their large industrial ***10U1 opens up a new capability to investigate phenomena such as non-equilibrium and dynamic processes of materials with a wide length scale from angstroms to micrometers with millisecond time *** this paper,we also report beamline design considerations and commissioning results.

关键词： Synchrotron radiation Ultra-small-angle X-ray scattering Micro small-angle X-ray scattering USAXS Time resolved μSAXS

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Controlled Fabrication of Uniform Digital Nanorods from Precise Sequence-Defined Amphiphilic Polymers in Aqueous Media

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Chinese Journal of Polymer Science 2023年第5期41卷 768-777,I0010页

作者： qiang-qiang shi Xin Zhou Jie Xu Ning Wang Jia-Lin Zhang xiang-Long Hu shi-Yong Liu CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China School of Biomedical Engineering and Suzhou Institute for Advanced Research University of Science and Technology of ChinaSuzhou 215123China

Compared with spherical micelles,rod/worm-like micelles not only have extended blood circulation duration,but also exhibit favorable cellular uptake behavior,which is promising for next-generation nanomedicine and ***,the controllable fabrication of narrowly dispersed nanorods in aqueous media is still ***,the methodology of thermal annealing was developed for the fabrication of helical nanorods as well as a series of nanorods with different *** thermal annealing process generally consisted of adding a percentage of organic solvent(10%(V/V)or 20%(V/V))to the digital micellar aqueous dispersion,followed by heating at 90℃for 1 h,then cooling naturally to room temperature,and dialyzing against water to remove the organic ***-handed helical nanorods were afforded by the treatment of 45 nm digital micelles in the presence of 10%(V/V)dioxane,while left-handed helical nanorods were obtained in the presence of 20%(V/V)***,the controlled growth of rod-like digital micelles was achieved after thermal annealing in the presence of different types of organic solvents,and the length of the annealed nanorods was correlated with the types of organic ***,no matter the size of initial digital micelles,they all exhibited similar trend of rod growth in the presence of a certain amount of organic solvent,allowing for controllable formulation of narrowly dispersed *** addition,supramolecular self-assembly by amphiphilic dendritic oligourethane readily fabricated diverse uniform nanorods in aqueous ***,this work provided an attractive methodology to fabricate uniform digital nanorods.

关键词： Sequence-defined amphiphilic polymers Digital nanorods Thermal annealing Dendritic oligourethane Self-assembly

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Dual mechanisms of Bcl-2 regulation in IP_(3)-receptor-mediated Ca^(2+)release:A computational study

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Chinese Physics B 2021年第10期30卷 689-697页

作者： Hong Qi Zhi-qiang shi Zhi-Chao Li Chang-Jun Sun shi-miao Wang xiang Li Jian-Wei Shuai Complex Systems Research Center Shanxi UniversityTaiyuan 030006China Shanxi Key Laboratory of Mathematical Techniques and Big Data Analysis on Disease Control and Prevention Shanxi UniversityTaiyuan 030006China School of Mathematical Sciences Shanxi UniversityTaiyuan 030006China Department of Physics and Fujian Provincial Key Laboratory for Soft Functional Materials Research Xiamen UniversityXiamen 361005China State Key Laboratory of Cellular Stress Biology Innovation Center for Cell Signaling Networkand National Institute for Data Science in Health and MedicineXiamen UniversityXiamen 361005China

Inositol 1,4,5-trisphosphate receptors(IP_(3)R)-mediated calcium ion(Ca^(2+))release plays a central role in the regulation of cell survival and ***-2 limits the Ca^(2+)release function of the IP3R through a direct or indirect ***,the two mechanisms are overwhelmingly complex and not completely ***,we convert the mechanisms into a set of ordinary differential *** firstly simulate the time evolution of Ca^(2+)concentration under two different levels of Bcl-2 for the direct and indirect mechanism models and compare them with experimental results available in the ***,we employ one-and two-parameter bifurcation analysis to demonstrate that Bcl-2 can suppress Ca^(2+)signal from a global point of view both in the direct and indirect mechanism *** then use mathematical analysis to clarify that the indirect mechanism is more efficient than the direct mechanism in repressing Ca^(2+)***,we predict that the two mechanisms restrict Ca^(2+)signal ***,our study provides theoretical insights into Bcl-2 regulation in IP_(3)R-mediated Ca^(2+)release,which may be instrumental for the successful development of therapies to target Bcl-2 for cancer treatment.

关键词： Ca^(2+) Bcl-2 bifurcation analysis oscillations

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Endoscopic resection of colorectal granular cell tumors

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World Journal of Gastroenterology 2015年第48期21卷 13542-13547页

作者： Iri Take qiang shi Zhi-peng Qi shi-lun Cai li-Qing Yao ping-hong Zhou yun-shi Zhong Endoscopy Center Zhongshan Hospital of Fudan University Endoscopy Research Institute of Fudan University

AIM: To determine the feasibility and effectiveness of endoscopic resection for the treatment of colorectal granular cell tumors(GCTs). METHODS: This was a retrospective study performed at a single institution. From January 2008 to April 2015, we examined a total of 11 lesions in 11 patients who were treated by an endoscopic procedure for colorectal GCTs in the Endoscopy Center, Zhongshan hospital of Fudan University, Shanghai, China. Either endoscopic mucosal resection or endoscopic submucosal dissection(ESD) was performed by three surgeons with expertise in endoscopic treatment. The pre- and postoperative condition and follow-up of these patients were evaluated by colonoscopy and endoscopic ultrasonography(EUS).RESULTS: Of these 11 lesions, 2 were located in the cecum, 3 were in the ileocecal junction, 5 were in the ascending colon, and 1 was in the rectum. The median maximum diameter of the tumors was 0.81 cm(range 0.4-1.2 cm). The en bloc rate was 100%, and the complete resection rate was 90.9%(10/11). postoperative pathology in one patient showed a tumor at the cauterization margin. however, during ESD, this lesion was removed en bloc, and no tumor tissue was seen in the wound. No perforations or delayed perforations were observed and emergency surgery was not required for complications. All patients were followed up to May 2015, and none had recurrence, metastasis, or complaints of ***: Endoscopic treatment performed by endoscopists with sufficient experience appears to be feasible and effective for colorectal GCTs.

关键词： Endoscopic submucosal dissection granularcell tumors Endoscopic mucosal resection colorectal

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Population Genetic Analysis of Blumeria graminis f. sp. tritici in Qinghai Province, China

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Journal of Integrative Agriculture 2014年第9期13卷 1952-1961页

作者： XU Zhi DUAN Xia-yu ZHOU Yi-lin guo Qing-yun YAO qiang CAO shi-qin State Key Laboratory for the Biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences Institute of Plant Protection Qinghai Academy of Agricultural and Forestry Institute of Plant Protection Gansu Academy of Agricultural Sciences

To gain more precise information about molecular genetic variation for wild populations of Blumeria graminis f. sp. tritici from Qinghai Province, China, 38 single-colony isolates were purified from samples collected from Haidong District, Xining City and Hainan Tibetan Autonomous Prefecture in 2010. The virulence of 21 isolates among them was tested at seedling stage on 34 wheat cultivars（lines） carrying known powdery mildew（Pm） resistant genes. The results showed that V1 a, V3 a, V3 c, V3 e, V5 a, V6, V7, V8 and V19 had high virulence frequencies（〉75%）, indicating a wide distribution; and V1 c, V5 b, V12, V13, V16, V21, VXBD, V2＋6, V2＋Mld and V4＋8, with less distribution, appeared to be lower in frequencies（0-20%）. The Nei＇s gene diversity（H）, Shannon＇s information index（I） and the percentage of polymorphic loci（P） were 0.23, 0.35 and 67.65%, respectively, which revealed a virulent diversity. The results from single nucleotide polymorphisms（SNPs） of 38 isolates showed that three housekeeping genes were found to contain a total of 9 SNP sites. 10 haplotypes（H1-H10） were inferred from the concatenated sequences, with 1 haplotype（H1） comprising of over 55% of Qinghai population. Phylogenic analysis did not show obvious geographical subdivision between the isolates. A multilocus haplotype network presented a radial structure, with H1 in the central as an inferred ancestor. Using analysis of molecular variance（AMOVA）, we found 1.63% of the total variation was among populations and 98.37% within populations, with a low fixations index（FST=0.01634, P〈0.05）. This revealed a relatively high genetic diversity but a low genetic divergence in Qinghai population. Moreover, the molecular data on gene flow（Nm=6.32） confirmed the migration of pathogen populations among areas in Qinghai Province.

关键词： Blumeria graminis f.sp.tritici virulence single nucleotide polymorphisms haplotype

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