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Effect of nitrogen and phosphorus on the water quality in the Three Gorges Reservoir Area during and after its construction

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Journal of Environmental Sciences 2004年第3期16卷 358-363页

作者： LIUHong LIUHui-juan QUJiu-hui StateKeyLaboratoryofEnvironmentalAquaticChemistry ResearchCenterforEco-EnvironmentalSciencesChineseAcademyofSciences.Beijing100085.China

A survey concerning the concentration of the nutrients in the Three Gorges Reservoir Area was carried out. This paper presents the parameters(NO 3 - N, NO 2 - N, Kjeldahl N, non ionic ammonia, P PO 4 and TP) determined at 16 sampling sites from 1997 to 1999 The dominant soluble nitrogen form was NO 3 - N followed by Kjeldahl N, NO 2 - N and non ionic ammonia. Mean values of NO 3 - N, NO 2 - N, Kjeldahl N and non ionic ammonia ranged from 0 50 to 2 37 mg/L, 0 022 to 0 084 mg/L, 0 33 to 0 99 mg/L and 0 007 to 0 092 mg/L respectively. Mean values of P PO 4 at most sampling sites were higher than 0 1 mg/L for subject to eutrophication. The major factors influencing the concentrations of N and P might be agricultural runoff, municipal and industrial effluents. In addition, 6 kinds of soil were sampled at the area where would inundated after the dam completed. Two approaches were adopted to simulate the N and P release from the inundated soils. The results showed that the soils would release nitrogen and phosphorus to the overlying water when the soils were inundated. The characteristics of soil affected the equilibrium concentrations of N and P between the soil and the overlying water.

关键词： Three Gorges Reservoir Area nitrogen phosphorus inundated soil

Relation among C-curve characterization diagrams

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第10期8卷 1663-1670页

作者： CAO juan WANG Guo-zhao Institute of Computer Graphics and Image Processing Department of Mathematics Zhejiang University Hangzhou 310027 China

As three control points are fixed and the fourth control point varies, the planar cubic C-curve may take on a loop, a cusp, or zero to two inflection points, depending on the position of the moving point. The plane can, therefore, be partitioned into regions labelled according to the characterization of the curve when the fourth point is in each region. This partitioned plane is called a "characterization diagram". By moving one of the control points but fixing the rest, one can induce different characterization diagrams. In this paper, we investigate the relation among all different characterization diagrams of cubic C-curves based on the singularity conditions proposed by Yang and Wang (2004). We conclude that, no matter what the C-curve type is or which control point varies, the characterization diagrams can be obtained by cutting a common 3D characterization space with a corresponding plane.

关键词： Spline C-curve Characterization diagram Singularity

Melamine/Stearic Acid Composite Nanowires and Vesicles with an Intercalated Nanostructure Prepared through NCCM Method

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Chinese Journal of Chemical Physics 2012年第6期25卷 708-712,I0004页

作者： juan Guo Dao-yong Chen The State Key Laboratory of Molecular Engineering of Polymers and Department of MacromolecularScience Fudan University Shanf hai 200433 China

A solvent-non-solvent method invented in our laboratory for preparing non-covalently con- nected micelles （NCCM） was used to intercalate melamine （MA） molecules into stearic acid （SA） bilayers to form tile composite nanoparticles with an intercalated nanostructure in which a melamine bilayer is sandwiched between two stearic acid bilayers, NCCM method helps to sufficiently mix the two components in nanospace and meanwhile inhibits the strong tendency of self-crystallization of MA, leading to the intercalation. Although the nanopar- ticles have a regular inner structure, the primary MA/SA nanoparticles have an irregular morphology. Regular nanoparticles were obtained through annealing the suspension of the primary nanoparticles. Through annealing at different temperatures, the MA/SA compos- ite nanowires and vesicles with an intercalated structure were prepared respectively. It is proposed that the morphological change results from the change in the intercalated structure.

关键词： Organic intercalation system Non-covalently connected micelles method Annealing treatment

Development of quadrilateral spline thin plate elements using the B-net method

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Acta Mechanica Sinica 2013年第4期29卷 567-574页

作者： juan Chen Chong-Jun Li School of Mathematics and Quantitative Economics Dongbei University of Finance and Economics School of Mathematical Sciences Dalian University of Technology

The quadrilateral discrete Kirchhoff thin plate bending element DKQ is based on the isoparametric element Q8, however, the accuracy of the isoparametric quadrilateral elements will drop significantly due to mesh distortions. In a previous work, we constructed an 8-node quadrilateral spline element L8 using the triangular area coordinates and the B- net method, which can be insensitive to mesh distortions and possess the second order completeness in the Cartesian co- ordinates. In this paper, a thin plate spline element is devel- oped based on the spline element L8 and the refined tech- nique. Numerical examples show that the present element indeed possesses higher accuracy than the DKQ element for distorted meshes.

关键词： Spline finite element ~ Refined quadrilateral el-ement ~ Discrete Kirchhoff plate element ~ Triangular areacoordinates ~ B-net method

基于生物信息学的胃癌关键糖酵解相关差异表达基因的鉴定及预后模型的构建

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医学分子生物学杂志 2025年第1期22卷 76-83页

作者：许娟胡琬琪仙桃市第一人民医院肿瘤科湖北省仙桃市433000 仙桃市第一人民医院胃肠外科湖北省仙桃市433000

目的应用生物信息学工具探索糖酵解相关基因(glycolysis-related genes,GRGs)在胃癌中的表达及基于其所构建的风险评分模型与胃癌患者预后的关系。方法从癌症基因组图谱(the cancer genome atlas,TC-GA)数据库下载胃癌组织转录组和临床... 详细信息

目的应用生物信息学工具探索糖酵解相关基因(glycolysis-related genes,GRGs)在胃癌中的表达及基于其所构建的风险评分模型与胃癌患者预后的关系。方法从癌症基因组图谱(the cancer genome atlas,TC-GA)数据库下载胃癌组织转录组和临床特征数据。从基因集富集分析(gene set enrichment analysis,GSEA)数据库中获得GRGs集。使用limma包来识别胃癌组织中差异表达的GRGs。使用单因素Cox回归分析筛选预后相关的GRGs,应用LASSO回归分析构建基于GRGs的预后预测模型。根据Cox回归分析确定的独立预后危险因素构建Nomogram图。最后,分析22种浸润性免疫细胞与GRGs、风险评分模型相关性。结果鉴定出21个差异表达的GRGs,其主要富集在酒精代谢过程和酪氨酸代谢途径。利用LASSO和Cox模型筛选出5个预后相关的糖酵解基因(ADH1B、ADH4、CLDN9、VCAN及LHX90),构建预测胃癌预后风险评分模型。低风险评分的胃癌患者总生存时间明显优于高风险评分的胃癌患者,ROC曲线分析显示该模型预测胃癌患者1年、3年及5年生存期曲线下面积(area under curve,AUC)值分别为0.602、0.680和0.802,发现该模型预测患者生存期的效能优于肿瘤分期及分级。单因素和多因素Cox分析显示构建的模型、患者的年龄、性别及肿瘤分期、分级是胃癌患者独立预后因素。基于独立危险因素构建了用来预测胃癌患者生存Nomogram图。最后,发现CD8 T细胞和辅助性滤泡T细胞比例在高危组中明显降低,而M0型和M2型巨噬细胞比例在高危组中明显高于低危组。辅助性滤泡T细胞与ADH1B表达水平、VCAN表达水平和风险评分呈负相关。M2型巨噬细胞与VCAN表达水平和风险评分呈正相关。结论研究筛选出胃癌预后相关的5个GRGs构建的模型可作为评估胃癌患者预后的可靠工具,为胃癌提供潜在的糖酵解治疗靶点。

关键词：胃癌糖酵解差异表达基因 Cox回归预后指标诺莫图

MECHANISM FOR VISCOELASTIC POLYMER SOLUTION PERCOLATING THROUGH POROUS MEDIA

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Journal of Hydrodynamics 2007年第2期19卷 241-248页

作者： ZHANG Li-juan YUE Xiang-an Ministry of Education Key Laboratory of Petroleum Engineering China University of Petroleum Beijing 102249 China

The pore throat of porous media is modeled as a constricted channel or expanded channel. The flow of viscoelastic polymer solution in pore throat model is studied by numerical method. Relationship between pressure drop and flow rate is developed, viscoelasticity and throat size are found to be two main factors in high flow resistance. According to pore throat model, 2-D stochastic channel bundle is put forward to model porous media, which is composed of pore throat models in series - parallel connection with size and length accord to Hating Greenkorn stochastic distribution. Percolation model of viscoelastic fluid is developed on the basis of Darcy equation and pressure drop vs. flow rate relation in 2-D stochastic channel bundle. Results indicate that the seepage ability of viscoelastic polymer solution decreases with the increase of viscoelasticity, injection rate, and heterogeneity as well as the decrease of mean pore size of porous media. The high pressure drop of viscoelastic fluid at the connection of pore to throat plays a great role in its anomalous high flow resistance through porous media.

关键词： polymer flooding viscoelastic fluid,flow resistance percolation pore throat

Dynamics of populations with two sexes

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International Journal of Biomathematics 2015年第4期8卷 127-144页

作者： M. Cecilia Perez E. Adriana Saavedra mariano A. Ferrari Facultad de Ingenieria Universidad Nacional de la Patagonia San Juan Bosco Esquel Chubut Argentina Facultad de Ingenieria Universidad Nacional de la Patagonia San Juan Bosco Trelew Chubut Argentina Facultad de Ingenierla Universidad Nacional de la Patagonia San Juan Bosco Puerto Madryn Chubut Argentina Centro Nacional Patagdnico CONICET Puerto Madryn Chubut Argentina

A mathematical model is presented in order to describe the dynamics of polygamous populations, bearing in mind single individuals of both sexes and the development of reproductive groups. In this context, the description leads us to consider positive homogeneous dynamical systems, establishing conditions for the stationary state existence and its local stability. A fourth pre-reproductive stage was considered, i.e. males and females spend part of their lives before being in condition to reproduce, as a first step to consider more general models. Finally, we parametrized the proposed model using southern elephant seal data, to analyze the direct applicability to a real population.

关键词： Dynamical systems two-sex model mating system local stability.

Drinking water production by uitrafiltration of Songhuajiang River with PAC adsorption

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Journal of Environmental Sciences 2007年第5期19卷 536-539页

作者： XIA Sheng-ji LIU Ya-nane LI Xing YAO juan-juan State Key laboratory of Pollution Control and Resources Reuse Tongji University Shanghai 200092 China School of Environmental Science and Engineering Dong Hua UniversityShanghai 201620China School of Architecture and Civil Engineering Beijing University of Technology Bejing 100083 China

In recent years, membrane ultrafiltration （UF） of surface water for drinking water treatment has become a more attractive technology worldwide as a possible alternative treatment to conventional clarification. To evaluate the performance of ultrafiltration membranes for treatment of surface water in North China, a 48-m^2 low pressure hollow fiber membrane ultrafiltration pilot plant was constructed. Ultrafiltration was operated in cross-flow and with powdered activated carbon （PAC） adsorption. Turbidity was almost completely removed to less than 0.2 NTU （below Chinese standard 1 NTU）. It was found that PAC addition enhanced organic matter removal. The combined process of PAC/UF allowed to 41% removal of CODMn, 46% removal of DOC and 57% decrease in UV254 absorbance. The elimination of particles, from average 12000/ml in the raw water to approximately 15/ml in the permeated, was observed. When PAC concentration was below 30 mg/L, backwashing could recovery the membrane flux with backwash interval/backwashing duration of 1/30.

关键词： surface water drinking water treatment ultrafiltration powdered activated carbon

Late hepatic artery pseudoaneurysm:A rare complication after resection of hilar cholangiocarcinoma

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World Journal of Gastroenterology 2008年第38期14卷 5920-5923页

作者： Javier Briceńo lvaro naranjo Rubén Ciria juan Manuel Sánchez-Hidalgo Luis Zurera Pedro López-Cillero Hepatobiliary Surgery and Liver Transplantation Unit Department of Surgery Hospital Universitario Reina SofíaCórdoba 14004 Spain Interventional Radiology Unit Department of Surgery Hospital Universitario Reina SofíaCórdoba 14004 Spain

We report an unusual pathological entity of a pseudoaneurysm of the right hepatic artery, which developed two years after the resection of a type 11 hilar cholangiocarcinoma and secondary to an excessive skeletonization for regional lymphadenectomy and neoadjuvant external-beam radiotherapy. After a sudden and massive hematemesis, a multidetector computed tomographic angiography （MDCTA） showed a hepatic artery pseudoaneurysm. Angiography with embolization of the pseudoaneurysm was attempted using microcoils with adequate patency of the hepatic artery and the occlusion of the pseudoaneurysm. A new episode of hematemesis 3 wk later revealed a partial revascularization of the pseudoaneurysm. A definitive interventional radiological treatment consisting of transarterial embolization （TAE） of the right hepatic artery with stainless steel coils and polyvinyl alcohol particles was effective and welltolerated with normal liver function tests and without signs of liver infarction.

关键词： Hepatic artery pseudoaneurysm Hilar cholangiocarcinoma Pseudoaneurysm embolization Transarterial embolization Chemoradiotherapy