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Spatiotemporal variations of nitrate sources and dynamics in a typical agricultural riverine system under monsoon climate

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Journal of Environmental Sciences 2020年第7期32卷 98-108页

作者： Hao Jiang Wenjing Liu Jiangyi Zhang Li zhou Xiaode zhou Ke Pan Tong Zhao Yuchen wang Zhifang Xu institute for Advanced Study Shenzhen UniversityShenzhen518060China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China CAS Center for Excellence in Life and Paleoenvironment Beijing 100044China university of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430074China

Nitrogen pollution is a serious environmental issue in the Danjiangkou Reservoir region(DRR),the water source of the South-to-North Water Diversion Project of *** this research,seasonal surveys and a bi-weekly time series survey were conducted in the Qihe River Basin,one of the most densely populated agricultural basins in the *** compositions(NO3^-Cl^-),dual isotopes(δD-H2O,δ^18O-H2O,δ^15N-NO3^-,andδ^18O-NO3^-),and a Markov Chain Monte Carlo isotope mixing model were jointly applied to unravel the sources,migrations,and transformations of the nitrate(NO3^-)in the *** was revealed that the mixing between different sources was the main process controlling the isotopic compositions of the riverine NO3the upper-middle *** contrast,denitrification occurred in the lower *** the first time,the sources of NO3^-quantified at a basin scale in the ***,the river transported 484.2 tons/year of NO3^-N to the reservoir,of which 32.6%,36.4%,28.0%,and 3.0%was from soil organic nitrogen,chemical fertilizer,residential sewage and atmospheric precipitation,*** NO3^-N fluxes of the different sources were regulated by the monsoon climate and anthropogenic *** example,high precipitation and intense fertilization resulted in severe nonpoint source *** thrived in soils and reservoirs in wet *** could regulate the migration,nitrification and denitrification *** on the results,we suggest that the management strategies dealing with nitrogen pollution issue in the DRR should follow the specific spatiotemporal characteristics of NO3migration and transformation mechanisms.

关键词： Nitrate Source Dynamics Isotope MCMC mixing model

Non-artifact vector P- and S-wave separation for elastic reverse time migration

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Petroleum Science 2022年第6期19卷 2695-2710页

作者： Xi-Yan zhou Xu Chang Yi-Bo wang Xiao-Tao Wen Jia-Chun You Chang Sun Key Laboratory of Earth Exploration and Information Techniques Chengdu University of TechnologyChengdu610059SichuanChina College of geophysics Chengdu University of TechnologyChengdu610059SichuanChina Key Laboratory of Shale Gas and Geoengineering Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China Key Laboratory of Petroleum Resource Research Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China

Elastic reverse time migration(RTM)uses the elastic wave equation to extrapolate multicomponent seismic data to the subsurface and separate the elastic wavefield into P-and S-waves.P-and S-wave separation is a necessary step in elastic RTM to avoid crosstalk between coupled ***,the current curl-divergence operator-based separation method has a polarity reversal problem in PS imaging,and vector separation methods often have separation artifacts at the interface,which affects the quality of the imaging *** propose a non-artifact P-and S-wave separation method based on the first-order velocity-strain *** equation is used for wavefield extrapolation and separation in the first-order staggered-grid finite-difference scheme,and the storage and calculation amounts are consistent with the classical first-order velocity-stress *** separation equation does not calculate the partial derivatives of the elastic parameters,and thus,there is no artifact in the separated Pand *** wavefield extrapolation,the dynamic characteristics of the reflected wave undergo some changes,but the transmitted wavefield is accurate;therefore,it does not affect the dynamic characteristics of the final migration *** numerical examples of 2 D simple models,part SEAM model,BP model,and 3 D 4-layer model,different wavefield separation methods and corresponding elastic RTM imaging results are *** found that the velocity-strain based elastic RTM can image subsurface structures well,without spike artifacts caused by separation artifacts,and without polarity reversal phenomenon of the PS imaging.

关键词： Multicomponent Elastic RTM P-and S-Wave separation Separation artifacts Decoupled velocity-strain equations

Agricultural Risk Factors Influence Microbial Ecology in Honghu Lake

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Genomics, Proteomics & Bioinformatics 2019年第1期17卷 76-90页

作者： Maozhen Han Melissa Dsouza Chunyu zhou Hongjun Li Junqian Zhang Chaoyun Chen Qi Yao Chaofang Zhong Hao zhou Jack A Gilbert Zhi wang Kang Ning Key Laboratory of Molecular Biophysics of the Ministry of Education Hubei Key Laboratory of Bioinformatics and Molecularimaging Department of Bioinformatics and Systems Biology College of Life Science and Technology Huazhong University of Science and Technology Key Laboratory for Environment and Disaster Monitoring and Evaluation of Hubei Institute of Geodesy and GeophysicsChinese Academy of Sciences The Microbiome Center Department of Surgery University of Chicago Argonne National Laboratory Biosciences Division Marine Biological Laboratory State Key Laboratory of Water Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences

Agricultural activities, including stock-farming, planting industry, and fish aquaculture,can affect the physicochemical and biological characters of freshwater lakes. However, the effects of pollution producing by agricultural activities on microbial ecosystem of lakes remain ***, in this work, we selected Honghu Lake as a typical lake that is influenced by agriculture activities. We collected water and sediment samples from 18 sites, which span a wide range of areas from impacted and less-impacted areas. We performed a geospatial analysis on the composition of microbial communities associated with physicochemical properties and antibiotic pollution of samples. The co-occurrence networks of water and sediment were also built and analyzed. Our results showed that the microbial communities of impacted and less-impacted samples of water were largely driven by the concentrations of TN, TP, NO_3^--N, and NO_2^--N, while those of sediment were affected by the concentrations of Sed-OM and Sed-TN. Antibiotics have also played important roles in shaping these microbial communities: the concentrations of oxytetracycline and tetracycline clearly reflected the variance in taxonomic diversity and predicted functional diversity between impacted and less-impacted sites in water and sediment samples, respectively. Furthermore, for samples from both water and sediment, large differences of network topology structures between impacted and less-impacted were also observed. Our results provide compelling evidence that the microbial community can be used as a sentinel of eutrophication and antibiotics pollution risk associated with agricultural activity; and that proper monitoring of this environment is vital to maintain a sustainable environment in Honghu Lake.

关键词： Freshwater Microbial communities Agriculture activities Antibiotics Human impact

Amorphous calcium magnesium phosphate nanocomposites with superior osteogenic activity for bone regeneration

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Regenerative Biomaterials 2021年第6期8卷 249-259页

作者： yingying Jiang Shuo Tan Jianping Hu Xin Chen Feng Chen Qianting Yao Zhi zhou Xiansong wang Zifei zhou Yunshan Fan Junjian Liu Yize Lin Lijia Liu Shisheng He Department of Orthopedic Spinal Pain Research InstituteShanghai Tenth People’s HospitalTongji University School of MedicineShanghai 200072China institute of Translational Medicine Shanghai UniversityShanghai 200444China National Engineering Research Center for Nanotechnology Shanghai 200241China institute of Functional Nano&Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials&DevicesSoochow UniversitySuzhou 215123China Shanghai Key Laboratory of Tissue Engineering Shanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghai 200011China

The seek of bioactive materials for promoting bone regeneration is a challenging and longterm *** with inorganic metal ions or drug molecules is considered effective strategies to improve the bioactivity of various existing ***,amorphous calcium magnesium phosphate(ACMP)nanoparticles and simvastatin(SIM)-loaded ACMP(ACMP/SIM)nanocomposites were developed via a simple co-precipitation *** physiochemical property of ACMP/SIM was explored using transmission electron microscope(TEM),Fourier transform infrared spectroscopy(FTIR),powder X-ray diffraction(XRD)and highperformance liquid chromatograph(HPLC),and the role of Mg^(2+) in the formation of ACMP/SIM was revealed using X-ray absorption near-edge structure(XANES).After that,the transformation process of ACMP/SIM in simulated body fluid(SBF)was also tracked to simulate and explore the in vivo mineralization performance of *** find that ACMP/SIM releases ions of Ca^(2+),Mg^(2+)and PO_(4)^(3),when it is immersed in SBF at 37℃,and a phase transformation occurred during which the initially amorphous ACMP turns into self-assembled hydroxyapatite(HAP).Furthermore,ACMP/SIM displays high cytocompatibility and promotes the proliferation and osteogenic differentiation of MC3T3-E1 *** the in vivo studies,lamellar ACMP/SIM/Collagen scaffolds with aligned pore structures were prepared and used to repair a rat defect model in ***/SIM/Collagen scaffolds show a positive effect in promoting the regeneration of calvaria defect after *** bioactive ACMP/SIM nanocomposites are promising as bone repair *** the facile preparation process and superior in vitro/vivo bioactivity,the as-prepared ACMP/SIM would be a potential candidate for bone related biomedical applications.

关键词： biomineralization bone materials synthesize biomaterial-cell

A Great late Ediacaran ice age

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National Science Review 2023年第8期10卷 105-118页

作者： Ruimin wang Bing Shen Xianguo Lang Bin Wen Ross N. Mitchell Haoran Ma Zongjun Yin Yongbo Peng Yonggang Liu Chuanming zhou Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education and School of Earth and Space SciencesPeking University 2. State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation and Institute of Sedimentary GeologyChengdu University of Technology 3. State Key Laboratory of Geological Processes and Mineral Resources School of Earth Sciences China University of Geosciences State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences College of Earth and Planetary Sciences University of Chinese Academy of Sciences School of Earth Sciences and Engineering Nanjing University State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and Paleoenvironment Chinese Academy of Sciences School of Physics Peking University

The emergence of the Ediacara biota soon after the Gaskiers glaciation ca. 580 million years ago(Ma)implies a possible glacial fuse for the evolution of animals. However, the timing of Ediacaran glaciation remains controversial because of poor age constraints on the ～30 Ediacaran glacial deposits known worldwide. In addition, paleomagnetic constraints and a lack of convincing Snowball-like cap carbonates indicate that Ediacaran glaciations likely did not occur at low latitudes. Thus, reconciling the global occurrences without global glaciation remains a paradox. Here, we report that the large amplitude, globally synchronous ca. 571–562 Ma Shuram carbon isotope excursion occurs below the Ediacaran Hankalchough glacial deposit in Tarim, confirming a post-Shuram glaciation. Leveraging paleomagnetic evidence for a～90° reorientation of all continents due to true polar wander, and a non-Snowball condition that rules out low-latitude glaciations, we use paleogeographic reconstructions to further constrain glacial ages. Our results depict a ‘Great Ediacaran Glaciation’ occurring diachronously but continuously from ca.580–560 Ma as different continents migrated through polar–temperate latitudes. The succession of radiation, turnover and extinction of the Ediacara biota strongly reflects glacial–deglacial dynamics.

关键词： carbonate carbon isotopes Shuram excursion inertial interchange true polar wander (IITPW) hankalchough glaciation Tarim Block

基于无人机倾斜摄影三维建模的数字露头及其在剖面实测和研究中的应用——以宁夏中卫下河沿剖面为例

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物探化探计算技术 2024年第4期46卷 490-498页

作者：魏文强陈建华王峰李晶王集周文峰吴静仪肖云宵成都理工大学地球物理学院成都610059 成都理工大学沉积地质研究院成都610059

传统野外剖面实测无法从整体和全局角度对剖面进行研究,实测工作受地形起伏影响较大,难以测量高危险区露头,地质学家根据实测数据所建二维露头地质模型难以在空间位置上与剖面紧密关联。论文分析了实测剖面所面临的问题,通过无人机倾斜... 详细信息

传统野外剖面实测无法从整体和全局角度对剖面进行研究,实测工作受地形起伏影响较大,难以测量高危险区露头,地质学家根据实测数据所建二维露头地质模型难以在空间位置上与剖面紧密关联。论文分析了实测剖面所面临的问题,通过无人机倾斜摄影技术采集不同航高的带有坐标信息和纹理特征的露头倾斜影像,使用处理软件构建露头三维模型,具备覆盖范围广、剖面重点岩层精度高等优势,能弥补传统野外剖面实测的不足。笔者将剖面实测与无人机倾斜摄影三维建模技术相结合,利用露头三维模型辅助剖面实测和研究工作。研究表明:(1)露头三维模型具备真实三维场景和坐标信息等优势,能从任意位置和角度进行剖面研究,尤其是高坡、悬崖等危险露头区;(2)露头三维模型能从整体和全局角度进行剖面实测路线规划、标定地层界限、记录实测轨迹及重要地质观察点等信息;(3)利用露头模型重点岩层区具备毫米级分辨率图像,能清晰、直观地进行剖面岩层分层、岩性识别、厚度量算及沉积旋回分析;(4)能轻易地解决剖面实测中对高陡长剖面的岩层层面追踪的问题;(5)对地层重点分界线,可进行剖面发育情况,组间接触情况和剖面岩层层序的划分。因此,将露头三维模型应用在剖面实测和研究中,对剖面实测工作的开展及露头地质知识库的建立大有裨益。

关键词：无人机倾斜摄影露头三维建模剖面实测下河沿

微载体规模化培养草鱼鳔细胞以增殖Ⅱ型草鱼呼肠孤病毒的工艺研究

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海洋渔业 2022年第5期44卷 577-588页

作者：杨玉茹王英英王庆周文礼尹纪元石存斌天津农学院水产学院天津300384 中国水产科学研究院珠江水产研究所农业农村部渔药创制重点实验室广东省水产动物免疫与绿色养殖重点实验室广州510380

为优化草鱼(Ctenopharyngodon idella)鳔细胞(CiSB)细胞悬浮培养工艺,以提高基因Ⅱ型草鱼呼肠孤病毒(grass carp reovirus,GCRV)含量,利用Cytodex 1微载体悬浮培养系统规模化培养CiSB和Ⅱ型GCRV,对CiSB细胞初始接种密度、搅拌转速和微... 详细信息

为优化草鱼(Ctenopharyngodon idella)鳔细胞(CiSB)细胞悬浮培养工艺,以提高基因Ⅱ型草鱼呼肠孤病毒(grass carp reovirus,GCRV)含量,利用Cytodex 1微载体悬浮培养系统规模化培养CiSB和Ⅱ型GCRV,对CiSB细胞初始接种密度、搅拌转速和微载体浓度等工艺参数进行摸索和优化。结果显示,在CiSB细胞贴壁期,以转速30 r·min^(-1)、每静置30 min搅拌2 min的间歇搅拌方式培养最佳,4 h后细胞贴附率可达96%以上;在微载体密度2 g·L^(-1)、细胞初始接种密度2×10^(5)个·mL^(-1)、搅拌速度30 r·min^(-1)的条件下,初始培养血清浓度设定为10%,培养3 d后更换50%的培养基并使血清浓度达到5%,可获得最佳的细胞生长效能。CiSB经消化转移放大至1 L,微载体上细胞贴附均匀、生长良好。接种Ⅱ型GCRV至规模化培养的CiSB细胞,拷贝数最高达6.2×10^(5)拷贝数·μL^(-1)。研究结果可为草鱼出血病疫苗的规模化生产工艺研究提供依据。

关键词：草鱼鳔细胞(CiSB) Ⅱ型草鱼呼肠孤病毒微载体培养工艺优化

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成人线状硬皮病伴眼睑下垂1例并文献复习

中华神经科杂志 2022年第7期55卷 732-737页

作者：王蘋徐营营周晓艳王梦宇王萍周桂芝程玲孙琳毕建忠山东大学第二医院神经内科济南250033 上海交通大学附属第六人民医院眼科上海200233 山东第一医科大学附属皮肤病医院(山东省皮肤病医院)病理科济南250022

目的探讨线状硬皮病的临床特点、诊断及治疗。方法总结2020年10月20日就诊于山东大学第二医院的1例线状硬皮病患者的临床资料和诊治过程,同时系统性回顾国内外文献所发表的硬皮病的病例报告或病例系列研究,分析其性别、年龄、发病时间... 详细信息

目的探讨线状硬皮病的临床特点、诊断及治疗。方法总结2020年10月20日就诊于山东大学第二医院的1例线状硬皮病患者的临床资料和诊治过程,同时系统性回顾国内外文献所发表的硬皮病的病例报告或病例系列研究,分析其性别、年龄、发病时间、临床表现、治疗及预后等情况。结果本例患者为24岁女性,有头皮斑痕样脱发和同侧面部凹陷病史10余年,因"2年前出现右侧眼睑无力、下垂,加重1个月"就诊,接受糖皮质激素治疗,效果欠佳。分析文献报道的全部15例患者,发病年龄中位数为22岁,男女比例为9∶6,表现为线状硬皮病伴有同侧眼睑下垂、同侧面部萎缩和颅内脱髓鞘病灶者4例,线状硬皮病合并同侧面部萎缩及颅脑脱髓鞘病灶者3例,线状硬皮病合并大脑半球萎缩2例,线状硬皮病合并同侧面部萎缩3例,线状硬皮病合并同侧面肌痉挛者1例,线状硬皮病合并胸腹部硬化性斑2例,线状硬皮病并癫痫发作并脑白质脱髓鞘病灶者2例。治疗方面,单纯应用激素治疗者有6例,单纯应用甲氨蝶呤者2例,激素合并甲氨蝶呤治疗者1例,应用氢化可的松乳膏外用2例,行骨重建手术3例,长波紫外线光疗治疗1例,应用维生素治疗1例。结论硬皮病患者可以出现同侧面部萎缩、同侧眼睑下垂和面肌痉挛等表现,累及神经系统可以出现癫痫发作和脊髓炎等表现,影像学可见脱髓鞘病变等,应结合患者的病理进行临床诊断。局限性线状硬皮病可以逐渐往系统性线状硬皮病的方向发展,因此治疗上主要以激素为主,必要时建议及早联合免疫抑制剂来控制疾病的发展。

关键词：硬皮病,局限性眼睑下垂面部单侧萎缩脱髓鞘疾病

不同提取方法的桑叶提取物对小鼠生长性能、抗氧化和免疫功能的作用研究

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动物营养学报 2022年第4期34卷 2702-2711页

作者：黄慧夏鑫周应军刘莹莹王贤泽王霞肖定福湖南农业大学动物科学技术学院长沙410128 湖南今汉药业有限公司长沙410014 湖南省畜牧兽医研究所长沙410131

本试验旨在通过探究不同桑叶提取段及桑叶粗提取物对小鼠生长性能、抗氧化功能、血清生化指标和炎症细胞因子的影响,筛选出一种较有效的桑叶提取方法。试验使用正己烷、乙酸乙酯、乙醇(85%)和水(60~70℃)制得桑叶提取物,另外使用水煎煮... 详细信息

本试验旨在通过探究不同桑叶提取段及桑叶粗提取物对小鼠生长性能、抗氧化功能、血清生化指标和炎症细胞因子的影响,筛选出一种较有效的桑叶提取方法。试验使用正己烷、乙酸乙酯、乙醇(85%)和水(60~70℃)制得桑叶提取物,另外使用水煎煮的方法制得桑叶粗提物,分别记为A、B、C、D和E。选取108只5周龄无特定病原体(SPF)级ICR雄性小鼠,随机分为6组,对照组饲喂基础饲粮,试验组在基础饲粮中分别添加桑叶提取物A、B、C、D和E(1200 mg/kg),每组6个重复,每个重复3只小鼠,预试期3 d,正试期28 d。结果显示:与对照组相比,1)E组小鼠的平均日采食量(ADFI)极显著提高(P1);2)C、D和E组小鼠血清谷胱甘肽过氧化物酶(GSH-Px)活性显著升高(P1);血清高密度脂蛋白胆固醇(HDL-C)含量显著降低(P3)A、C、D、E组小鼠肝脏中白细胞介素(IL)-17含量极显著升高(P1),肝脏IL-2含量极显著下降(P1),A、C、D组肝脏IL-1β和干扰素-γ(IFN-γ)含量极显著升高(P1),A组肝脏肿瘤坏死因子-α(TNF-α)含量显著升高(P1200 mg/kg的桑叶粗提物能提高小鼠平均日采食量,增强小鼠机体抗氧化能力,有益调节血清生化指标,改善肝脏功能,激活免疫反应,初步筛选出桑叶粗提物作用效果最好。

关键词：桑叶提取物小鼠抗氧化功能生长性能血清生化指标炎症细胞因子