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Risk Assessment of Highways Affected by Debris Flows in Wenchuan Earthquake Area

Journal of Mountain Science 2013年第2期10卷 173-189页

作者： CUI Peng XIANG ling-zhi ZOU Qiang Institute of Mountain Hazards and Environment/Key Laboratory of Mountain Hazards and Earth Surface Process Chinese Academy of Sciences Chongqing Jiaotong University Graduate University Chinese Academy of Sciences College of Environmental and Resource Southwest University of Science and TechnologyChina

Since the Wenchuan earthquake in China on May 12th, 2008, highways in earthquake-affected areas have been frequently interrupted by debris flows. We analyzed the hazard effect modes and damage processes along highways and developed three key indexes, scale of debris flows, deposits on highways and river blockage, to describe quantitatively the highway disasters. By combining the empirical methods and the actual terrain conditions, we proposed new methods to determine the value of hazard indexes. In addition, we used the economic value and resistance of highway as vulnerability assessment indexes, then determined the specific subindexes for the subgrade, bridges and culverts, and developed a way for the quantified vulnerability zoning. Moreover, we proposed the assessment and mapping methods for highway risk. The risk is described into 5 grades： extremely low risk, low risk, middle risk, high risk and extremely high risk. We applied these methods in a case study carried out on provincial highway S3o3 from Yingxiu Town to Wolong Town, in Wenchuan County. Analysis of debris flow risk for the whole highway, showed that the total length of highway in extremely low risk area was 28.26 km, 4.83 km in low risk area, 8.0 km in middle risk area, 3.65 km in high risk area, and 3.06 km in extremely high risk area. The assessment results are consistent with the field survey data which reflected the disaster situation. This risk method can be used objectively to evaluate the debris-flow risk along highways, and is useful for highway reconstruction in mountainous areas suffering from active debris flows.

关键词： Debris flow Highway disaster Hazardanalysis Vulnerability analysis Risk analysis Wenchuan earthquake

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Designer cell-self-implemented labeling of microvesicles in situ with the intracellular-synthesized quantum dots

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Science China Chemistry 2020年第4期63卷 448-453页

作者： ling-Hong Xiong Jia-Wei Tu Ya-Nan Zhang ling-ling Yang Ran Cui zhi-ling Zhang Dai-Wen Pang College of Chemistry and Molecular Sciences State Key Laboratory of VirologyInstitute for Advanced Studiesand Wuhan Institute of BiotechnologyWuhan UniversityWuhan 430072China State Key Laboratory of Medicinal Chemical Biology Tianjin Key Laboratoryof Biosensing and Molecular RecognitionResearch Center for Analytical Sciencesand College of ChemistryNankai UniversityTianjin 300071China

Cell-derived microvesicles(MVs) are secreted from almost all kinds of mammalian cells into the extracellular space, and play crucial roles in intercellular communication and transporting biomolecules between cells. However, there is a great challenge for visualizing and monitoring of MVs’ bio-behaviors due to the limitations of existing labeling methods. Herein, we report the first paradigm of designer cell-self-implemented labeling of MVs secreted from living mammalian MCF-7 cells in situ using the intracellular-synthesized fluorescent quantum dots(QDs) during the formation of MVs. By elaborately coupling intracellular biochemical reactions and metabolism pathways, the MCF-7 cells can be illuminated brightly by intracellular-biosynthesized fluorescent CdSe QDs. Simultaneously, intracellular-synthesized QDs can be in situ encapsulated by the secreted MVs budding from the plasma membrane of the fluorescing cells to label the MVs with an efficiency of up to 89.9%. The whole labeling process skillfully combines designer precise cell-tuned intricate synthesis of CdSe QDs with mild in-situ labeling via cell-selfimplementation just after feeding the cell with suitable chemicals, which is structure-or function-nondestructive and much more straightforward and milder than those by chemical conjugation or indirect encapsulation with conventional fluorogenic labels.

关键词： in situ labeling live cell synthesis cell-derived microvesicles quantum dot cell-self-implementation

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甲烷在钠基蒙脱土吸附的第一性原理研究

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原子与分子物理学报 2025年第2期42卷 8-14页

作者：方志杰李博宋昌辉刘美玲何秋芝刘翔莫曼广西科技大学电子工程学院柳州545006 广西科技大学土木建筑工程学院柳州545006 广西科技大学医学部柳州545006

随着经济的发展,能源需求日益增加,为了弥补国内少油缺气短板,页岩气的开发成为近期新能源的热点,探索页岩气储存规律是页岩气能源开发的关键所在.本文采用密度泛函理论的第一性原理方法,计算甲烷(CH_(4))在钠基蒙脱土表面和层间的吸附... 详细信息

随着经济的发展,能源需求日益增加,为了弥补国内少油缺气短板,页岩气的开发成为近期新能源的热点,探索页岩气储存规律是页岩气能源开发的关键所在.本文采用密度泛函理论的第一性原理方法,计算甲烷(CH_(4))在钠基蒙脱土表面和层间的吸附能,对比吸附前后的态密度和物理结构以及差分电荷密度.结果表明:钠基蒙脱土表面吸附中,甲烷最佳选择是桥位,吸附能为-0.08eV,被吸附后甲烷的键长和键角变化率均小于0.96%.层间吸附中,伴随着甲烷吸附量增加,纳基蒙脱土体积向c轴方向线性增加,a、b轴方向则变化不大.总态密度随着吸附量的增加,总能级数量也增加,甲烷分子的分波态密度峰向低能级移动.本文的研究成果,从原子角度分析了甲烷在蒙脱石表面以及层间的吸附能力,为解释页岩气在页岩储存规律提供理论依据.

关键词：钠基蒙脱土第一性原理甲烷吸附态密度

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Prediction of the concentration of chlorophyll-α for Liuhai urban lakes in Beijing City

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Journal of Environmental Sciences 2006年第4期18卷 827-831页

作者： ZENG Yong YANG zhi-feng LIU Jing-ling State Key Laboratory of Water Environment Simulation School of-Environmental Beijing Normal University Beijing 100875 China Key Laboratory for Water and Sediment Sciences of Ministry of Education School of Environment Beijing Normal University Beijing 100875 China

The weekly water quality monitor data of Liuhai lakes between April 2003 and November 2004 in Beijing City were used as an example to build an artificial neural networks （ANN） model and a multi-varieties regression model respectively for predicting the fresh water algae bloom. The different predicted abilities of the two methods in Liuhai lakes were compared. A principle analysis method was first used to select the input variables of the models to avoid the phenomenon of collinearity in the data. The results showed that the input variables for the artificial neural networks were T, TP, transparency（SD）, DO, chlorophyll-a （Chl-a）,pH and the output variable was Chl-a. A three layer Levenberg-Marguardt feed forward leaming algorithm in ANN was used to model the eutrophication process of Liuhai lakes. 20 nodes in hidden layer and 1 node of output for the ANN model had been optimized by trial and error method. A sensitivity analysis of the input variables was performed to evaluate their relative significance in determining the predicted values. The correlation coefficient between predicted value and observed value in all data and in test data were 0.717 and 0.816 respectively in the artificial neural networks. The stepwise regression method was used to simulate the linear relation between Chl-a and temperature, of which the correlation coefficient was 0.213. By comparing the results of the two models, it was found that neural network models were able to simulate non-linear behavior in the water eutrophication process of Liuhai lakes reasonably and could successfully estimate some extreme values from calibration and test data sets.

关键词： artificial neural networks eutrophication multi-varieties regression forecast Liuhai lakes Beijing City

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Construction of nursing standard of integrated traditional Chinese and Western medicine for patients with COVID‑19 (mild and common) in Beijing based on Delphi method

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Journal of Integrative Nursing 2020年第4期2卷 172-178页

作者： Jing ZHANG Xue‑ling MA Jian‑Hua DENG Jing LI zhi‑Yun ZHANG ling tang School of Nursing Beijing University of Chinese MedicineBeijingChina Nephrology Department Dongfang Hospital of Beijing University of Chinese MedicineBeijingChina Department of Nursing Xiyuan Hospital CACMSBeijingChina Department of Nursing Beijing Ditan Hospital of Capital Medical UniversityBeijingChina Department of Nursing Dongfang Hospital of Beijing University of Chinese MedicineBeijingChina

Objective:The objective of this study is to establish a nursing standard of integrated traditional Chinese and Western medicine for patients with COVID‑19(mild and common)in Beijing,to provide reference for clinical nursing of patients with COVID‑19(mild and common).Methods:Through online communication meeting with nurses who are in the frontline of anti‑epidemic,clinical investigation,literature research,and expert demonstration meeting are carried out to prepare the draft of the standard,and the Delphi method is applied to determine the standard of integrated traditional Chinese and Western medicine care for patients with COVID‑19(mild and common)in ***:The nursing standard of integrated traditional Chinese and Western medicine for patients with COVID‑19(mild and common)was established,which included 5 first‑level indicators,14 second-level indicators and 60 third‑level *** two rounds of Delphi method,the positive coefficients of experts were 96%and 83%,the authoritative coefficients of experts were 0.89 and 0.91,and the Kendall’s coefficient of concordance(W)of experts were 0.12,0.09,0.10,0.13(P<0.05)and 0.44,0.43,0.37,0.39(P<0.05).Conclusion:The standard of integrated traditional Chinese and Western medicine nursing for patients with COVID‑19(mild and common)in Beijing constructed by the Delphi method is scientific and practical,which provides a reference for clinical application of integrated traditional Chinese and Western medicine nursing to fight against COVID‑19 infection.

关键词： Common COVID‑19 Delphi method integrated traditional Chinese and Western medicine nursing mild nursing standard

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Differential gene expression between asymptomatic HBV carriers and normal adults

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Hepatobiliary & Pancreatic Diseases International 2009年第4期8卷 383-388页

作者： tang, Cui-Lan Chen, zhi Zhejiang Univ Sch Med Affiliated Hosp 1 State Key Lab Diag & Treatment Infect Dis Hangzhou 310003 Zhejiang Peoples R China Xinhua Hosp Zhejiang Prov Dept Liver Dis Hangzhou 310005 Zhejiang Peoples R China

BACKGROUND: There are more than 100 million wa symptomatic HBV carriers (ASCs) in China and they are at a high risk of developing liver disease, which creates a serious health problem. But more than 90% of normal adults clear virus from primary HBV infection, so the difference of gene expression between ASCs and normal adults determines the differential outcomes. To identify differentially expressed genes in ASCs compared to normal adults, we used suppression subtractive hybridization to compare gene expression. METHODS: cDNA subtracted libraries were constructed by suppression subtracted hybridization from peripheral blood monocytes of ASCs and normal adults, the subtracted clones were prescreened by dot blot hybridization, and the levels of genes of interest were confirmed by real-time reverse transcriptase-polymerase chain reaction (RT-PCR). RESULTS: One hundred and two and 96 positive clones were acquired from the A-N and N-A libraries, respectively, and 14 and 11 clones were identified by dot blot hybridization in the A-N and N-A libraries. Two genes were confirmed as differentially expressed between a set of ASC and normal adult samples by real-time RT-PCR. CONCLUSIONS: Differentially expressed genes in peripheral blood mononuclear cells between ASCs and normal adults were isolated by suppression subtractive hybridization, and included some new genes. Of the upregulated genes in ASCs, checkpoint suppressor I is associated with DNA damage-induced cell cycle arrest. Perforin I is associated with inflammation. The information about such alterations in gene expression could be useful for elucidating the mechanisms of ASC pathogenesis.

关键词： hepatitis B virus asymptomatic HBV carriers suppression subtractive hybridization dot blot hybridization reverse transcriptase-polymerase chain reaction

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Non-asymptotic Error Bound for Optimal Prediction of Function-on-Function Regression by RKHS Approach

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Acta Mathematica Sinica,English Series 2022年第4期38卷 777-796页

作者： Hong zhi TONG ling Fang HU Michael NG School of Statistics University of International Business and EconomicsBeijing 100029P.R.China Department of Mathematics Hong Kong Baptist UniversityKowloon TongHong KongP.R.China Department of Mathematics The University of Hong KongPokfulamHong KongP.R.China

In this paper,we study and analyze the regularized least squares for function-on-function regression *** our model,both the predictors(input data)and responses(output data)are multivariate functions(with d variables andd variables respectively),and the model coefficient lies in a reproducing kernel Hilbert space(RKHS).We show under mild condition on the reproducing kernel and input data statistics that the convergence rate of excess prediction risk by the regularized least squares is minimax *** examples based on medical image analysis and atmospheric point spread function estimation are considered and tested,and the results demonstrate that the performance of the proposed model is comparable with that of other testing methods.

关键词： Regularized least squares function-on-function regression non-asymptotic error bound reproducing kernel Hilbert space integral operator

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Potential for Constraining Propagation Parameters of Galactic Cosmic Rays with the High Energy Cosmic-radiation Detection Facility on Board China's Space Station

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Research in Astronomy and Astrophysics 2023年第8期23卷 290-296页

作者： zhi-Hui Xu Qiang Yuan zhi-Cheng tang Xiao-Jun Bi Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

Precise measurements of the spectra of secondary and primary cosmic rays are crucial for understanding the origin and propagation of those energetic *** High Energy Cosmic-radiation Detection(HERD)facility on board China's Space Station,which is expected to operate in 2027,will push the direct and precise measurements of cosmic-ray fluxes up to PeV *** this work,we investigate the potential of HERD for studying the propagation of cosmic rays using measurements of boron,carbon,and oxygen *** find that,compared with the current results,the new HERD measurements can improve the accuracy of the propagation parameters by 8%–40%.The constraints on the injection spectra at high energies will also be improved.

关键词： (ISM:)cosmic rays-instrumentation detectors-The Galaxy

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An Overview of Molecular Packing Mode in Two-Dimensional Organic Nanomaterials via Supramolecular Assembly

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Chinese Journal of Chemistry 2019年第4期37卷 405-416页

作者： ling-zhi Jin Sha-Sha Wang ling-Hai Xie Wei Huang Centre for Molecular Systems and Organic Devices(CMSOD)&Key Laboratory for Organic Electronics and Information Displays&Institute of Advanced Materials(IAM)&Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM) Nanjing University of Posts&Telecommunications(NUPT)9 Wenyuan RoadNanjingJiangsu 210023China Shaanxi Institute of Flexible Electronics(SIFE) Northwestern Polytechnical University(NPU)127 West Youyi RoadXi'anShaanxi 710072China

Two-dimensional(2D)organic nanomaterials are attracting increasing research interest and expected to be the ideal candidate for futureproofed flexible electronics and *** to the complex molecular structures and multiple intermolecular interactions in organic systems,deeper understanding of rational molecular design and assembly principles is urgently *** this review,a collection of molecular packing mode in the 2D organic nanomaterials via supramolecular assembly is presented,so as to help explicit the relationship among molecular structures,supramolecular interactions and molecular packing motifs in 2D assembly *** also provide a rational and accessible schematic model to demonstrate several typical kinds of molecular packing motifs for the prediction of the 2D morphology.

关键词： Molecular Packing Mode Two-Dimensional Organic Nanomaterials Supramolecular Assembly

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The river chief system and agricultural non-point source water pollution control in China

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Journal of Integrative Agriculture 2021年第5期20卷 1382-1395页

作者： ZHOU Li LI ling-zhi HUANG Ji-kun College of Economics and Management Nanjing Agricultural UniversityNanjing 210095P.R.China China Center for Agricultural Policy School of Advanced Agricultural SciencesPeking UniversityBeijing 100871P.R.China Jiangxi Agricultural University Nanchang 330045P.R.China

As part of their efforts to control water pollution,local governments in China introduced the river chief system,whereby a named individual undertakes responsibility for protecting a specified *** one of the most prominent sources of water pollution,agricultural non-point-source(NPS)pollution is becoming increasingly *** whether the river chief system,an institutional reform in China's decentralized environmental regulation regime,is effective in alleviating NPS pollution is important for the realization of green *** effect of the river chief system on reducing agricultural NPS pollution is explored in this study using panel data from 308 Chinese counties during the period from 2004 to *** results reveal that the negative impact of manure output from animal breeding operations on surface water quality is reduced with the implementation of the river chief ***,the river chief system is ineffective in dealing with the water pollution caused by fertilizer ***,in the current system,cooperation among river chiefs only occurs within a *** governments should increase their efforts in reducing fertilizer source loads and preventing fertilizer loads from entering surface *** addition,the central government should improve cooperation among the river chiefs in upstream and downstream provinces.

关键词： river chief system agricultural non-point-source pollution surface water quality fertilizer use livestock and poultry breeding

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