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Impact of Drought on Agriculture in the Indo-Gangetic Plain,India

Advances in Atmospheric Sciences 2017年第3期34卷 335-346页

作者： Reshmita NATH Debashis NATH Qian LI Wen CHEN xuefeng cui Center for Monsoon System Research Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China School of System Sciences Beijing Normal UniversityBeijing 100875China Key Laboratory of Middle Atmosphere and Global Environmental Observations Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Meteorology and Climate Unit School of Mathematical ScienceUniversity College DublinDublin 4Ireland

In this study, we investigate the spatiotemporal characteristics of drought in India and its impact on agriculture during the summer season （April-September）. In the analysis, we use Standardized Precipitation Evapotranspiration Index （SPEI） datasets between 1982 and 2012 at the six-monthly timescale. Based on the criterion SPEI 〈 -1, we obtain a map of the number of occurrences of drought and find that the humid subtropical Upper Middle Gangetic Plain （UMGP） region is highly drought-prone, with an occurrence frequency of 40%-45%. This UMGP region contributes at least 18%-20% of India＇s annual cereal production. Not only the probability of drought, but the UMGP region has become increasingly drought-prone in recent decades. Moreover, cereal production in the UMGP region has experienced a gradual declining trend from 2000 onwards, which is consistent with the increase in drought-affected areas from 20%-25% to 50%-60%, before and after 2000, respectively. A higher correlation coefficient （-0.69） between the cereal production changes and drought-affected areas confirms that at least 50% of the agricultural （cereal） losses are associated with drought. While analyzing the individual impact of precipitation and surface temperature on SPEI at 6 month timescale [SPEI （6）] we find that, in the UMGP region, surface temperature plays the primary role in the lowering of the SPEI. The linkage is further confirmed by correlation analysis between SPEI （6） and surface temperature, which exhibits strong negative values in the UMGP region. Higher temperatures may have caused more evaporation and drying, which therefore increased the area affected by drought in recent decades.

关键词： drought agriculture SPEI Indo-Gangetic Plain temperature precipitation potential evapotranspiration

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Exploring Fragment Adding Strategies to Enhance Molecule Pretraining in AI-Driven Drug Discovery

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BIG DATA MINING AND ANALYTICS 2024年第3期7卷 565-576页

作者： Meng, Zhaoxu Chen, Cheng Zhang, Xuan Zhao, Wei cui, xuefeng Shandong Univ Sch Life Sci Qingdao 266237 Peoples R China Shandong Univ Sch Comp Sci & Technol Qingdao 266237 Peoples R China Shandong Univ State Key Lab Microbial Technol Qingdao 266237 Peoples R China

The effectiveness of Al-driven drug discovery can be enhanced by pretraining on small molecules. However, the conventional masked language model pretraining techniques are not suitable for molecule pretraining due to the limited vocabulary size and the non-sequential structure of molecules. To overcome these challenges, we propose FragAdd, a strategy that involves adding a chemically implausible molecular fragment to the input molecule. This approach allows for the incorporation of rich local information and the generation of a high-quality graph representation, which is advantageous for tasks like virtual screening. Consequently, we have developed a virtual screening protocol that focuses on identifying estrogen receptor alpha binders on a nucleus receptor. Our results demonstrate a significant improvement in the binding capacity of the retrieved molecules. Additionally, we demonstrate that the FragAdd strategy can be combined with other self-supervised methods to further expedite the drug discovery process.

关键词： Drugs Task analysis Databases Training Chemicals Vocabulary Fingerprint recognition pretraining information retrieval drug discovery virtual screening molecule property prediction

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Integrating global socio-economic influences into a regional land use change model for China

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Frontiers of Earth Science 2014年第1期8卷 81-92页

作者： Xia XU Qiong GAO Changhui PENG xuefeng cui Yinghui LIU Li JIANG State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Beijing 100875 China Department of Biology Sciences institute of environment Science University of Quebec at Montreal Montreal H3C 3P8 Canada College of Global Change and Earth System Research Beijing Normal University Beijing 100875 China Academy of Resource Beijing Normal University Beijing 100875 China Academy of Disaster Reduction and Emergency Management Beijing Normal University Beijing 100875 China

With rapid economic development and urba- nization, land use in China has experienced huge changes in recent years; and this will probably continue in the future. Land use problems in China are urgent and need further study. Rapid land-use change and economic development make China an ideal region for integrated land use change studies, particularly the examination of multiple factors and global-regional interactions in the context of global economic integration. This paper presents an integrated modeling approach to examine the impact of global socio-economic processes on land use changes at a regional scale. We develop an integrated model system by coupling a simple global socio-economic model （GLOBFOOD） and regional spatial allocation model （CLUE）. The model system is illustrated with an application to land use in China. For a given climate change, population growth, and various socio-economic situations, a global socio-economic model simulates the impact of global market and economy on land use, and quantifies changes of different land use types. The land use spatial distribution model decides the type of land use most appropriate in each spatial grid by employing a weighted suitability index, derived from expert knowledge abot^t the ecosystem state and site conditions. A series of model simulations will be conducted and analyzed to demonstrate the ability of the integrated model to link global socio- economic factors with regional land use changes in China. The results allow an exploration of the future dynamics of land use and landscapes in China.

关键词： global socio-economic influence land use change model integrating China

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Pedotransfer functions for predicting bulk density of coastal soils in East China

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Pedosphere 2023年第6期33卷 849-856页

作者： Guanghui ZHENG Caixia JIAO Xianli XIE xuefeng cui Gang SHANG Chengyi ZHAO Rong ZENG School of Geographic Sciences Nanjing University of Information Science&TechnologyNanjing 210044China Meteorology and Climate Centre School of Mathematics and StatisticsUniversity College DublinBelfieldDublin 4Ireland Institute of Soil Science Chinese Academy of ScienceNanjing 210008China School of Systems Science Beijing Normal UniversityBeijing 100875China

Soil bulk density(BD) is an important physical property and an essential factor for weight-to-volume conversion. However, BD is often missing from soil databases because its direct measurement is labor-intensive, time-consuming, and sometimes impractical, particularly on a large scale. Therefore, pedotransfer functions(PTFs) have been developed over several decades to predict BD. Here, six previously revised PTFs(including five basic functions and stepwise multiple linear regression(SMLR)) and two new PTFs, partial least squares regression(PLSR) and support vector machine regression(SVMR), were used to develop BD-predicting PTFs for coastal soils in East China. Predictor variables included soil organic carbon(SOC) and particle size distribution(PSD). To compare the robustness and reliability of the PTFs used, the calibration and prediction processes were performed 1 000 times using the calibration and validation sets divided by a random sampling algorithm. The results showed that SOC was the most important predictor, and the revised PTFs performed reasonably although only SOC was included. The PSD data were useful for a better prediction of BD, and sand and clay fractions were the second and third most important properties for predicting BD. Compared to the other PTFs, the PLSR was shown to be slightly better for the study area(the average adjusted coefficient of determination for prediction was 0.581). These results suggest that PLSR with SOC and PSD data can be used to fill in the missing BD data in coastal soil databases and provide important information to estimate coastal carbon storage, which will further improve our understanding of sea-land interactions under the conditions of ongoing global warming.

关键词： partial least squares regression particle size distribution soil organic carbon stepwise multiple linear regression support vector machine regression

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Evolving patterns of agricultural production space in China:A network-based approach

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Geography and Sustainability 2024年第1期5卷 121-134页

作者： Shuhui Yang Zhongkai Li Jianlin Zhou Yancheng Gao xuefeng cui School of Systems Science Beijing Normal UniversityBeijing 100875China State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China School of Natural Resources Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China Leibniz Institute for Agricultural Development in Transition Economies(IAMO) Halle(Saale)06120Germany

The agricultural production space,as where and how much each agricultural product grows,plays a vital role in meeting the increasing and diverse food *** studies on agricultural production patterns have predominantly centered on individual or specific crop types,using methods such as remote sensing or statistical metrological *** this study,we characterize the agricultural production space(APS)by bipartite network connecting agricultural products and provinces,to reveal the relatedness between diverse agricultural products and the spatiotemporal characteristic of provincial production capabilities in *** results show that core products are cereal,pork,melon,and pome fruit;meanwhile the milk,grape,and fiber crop show an upward trend in centrality,which is in line with diet structure changes in China over the past *** little changes in community components and structures of agricultural products and provinces reveal that agricultural production patterns in China are relatively ***,identified provincial communities closely resemble China's agricultural natural ***,the observed growth in production capabilities in North and Northeast China implies their potential focus areas for future agricultural *** the superior production capa-bilities of southern provinces,recent years have witnessed a notable decline,warranting special *** findings provide a comprehensive perspective for understanding the complex relationship of agricultural prod-ucts'relatedness,production capabilities and production patterns,which serve as a reference for the agricultural spatial optimization and agricultural sustainable development.

关键词： Agricultural system Complex network Agricultural production space Proximity matrix Production capability

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Direct anastomosis of contralateral C_7 nerve root transfer with affected-side inferior trunk for repair of brachial plexus avulsion injury

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Neural Regeneration Research 2006年第6期1卷 566-568页

作者： Houjun Yan Changqing Hu Yingli Jia Chunjie cui xuefeng Li Jingyang Zhang Department of Hand Surgery the 252 Hospital of Chinese PLA Baoding 071000 Hebei Province China

AIM： To observe the effect of direct anastomosis of contralateral C7 nerve root transferred through prespina route with affected-side infedor trunk for repair of brachial plexus avulsion injury, and investigate its feasibility. METHODS ： Two male patients, with the age of 24 and 41 years respectively, were retrieved. When admitted to the hospital, they were diagnosed as brachial plexus avulsion injury. They subjected the operation in the 252 Hospital of Chinese PLA in March 2006 and May 2006 respectively. The proximal end of contralateral C7 nerve root was dissociated to nerve root pore and the distal end was dissociated to anterior and posterior divisions of middle trunk. The injured C7 nerve root was widely dissociated to inferior trunk, medial cord, ulnar nerve and medial head of median nerve. When elbow and shoulder joints were in flexion, the injured C7 nerve root was directly anastomosed with contralateral C7 nerve root in the gap between affected-side cervical vagina vasorum and esophagus with no tensions. RESULTS： During 3 to 5 hours of operation, little hemorrhage was found, nerves were not used for connection. Dyspnea, hoarse voice and other complications did not appear, either. In the postoperative 7^th to 8^th months, electromyogram examination showed that the growth velocity of anastomosed nerve was normal. CONCLUSION ： Direct anastomosis of contralateral C7 nerve root transferred through prespinal route with affected-side inferior trunk can be used for repair of brachial plexus avulsion injury with satisfying therapeutic effects.

关键词： brachial plexus nerve root therapeutic effects median nerve velocity of the growth

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Research status and prospects of the fractal analysis of metal material surfaces and interfaces

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 20-38页

作者： Qinjin Dai xuefeng Liu Xin Ma Shaojie Tian Qinghe cui Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology BeijingBeijing 100083China Laboratory for Advanced Materials Processing of Ministry of Education University of Science and Technology BeijingBeijing 100083China School of Mechanical and Electrical Engineering Xinjiang Institute of EngineeringUrumqi 830023China

As a mathematical analysis method,fractal analysis can be used to quantitatively describe irregular shapes with self-similar or self-affine *** analysis has been used to characterize the shapes of metal materials at various scales and *** methods make it difficult to quantitatively describe the relationship between the regular characteristics and properties of metal material surfaces and ***,fractal analysis can be used to quantitatively describe the shape characteristics of metal materials and to establish the quantitative relationships between the shape characteristics and various properties of metal *** the perspective of two-dimensional planes and three-dimensional curved surfaces,this paper reviews the current research status of the fractal analysis of metal precipitate interfaces,metal grain boundary interfaces,metal-deposited film surfaces,metal fracture surfaces,metal machined surfaces,and metal wear *** relationship between the fractal dimensions and properties of metal material surfaces and interfaces is *** from three perspectives of fractal analysis,namely,research scope,image acquisition methods,and calculation methods,this paper identifies the direction of research on fractal analysis of metal material surfaces and interfaces that need to be *** is believed that revealing the deep influence mechanism between the fractal dimensions and properties of metal material surfaces and interfaces will be the key research direction of the fractal analysis of metal materials in the future.

关键词： metal material surfaces and interfaces fractal analysis fractal dimension homogeneity

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Arctic sea ice and atmospheric circulation under the abrupt4xCO2 scenario

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Advances in Polar Science 2014年第4期25卷 234-245页

作者： YU Xiaoyong Annette Rinke JI Duoying cui xuefeng John C.Moore State Key Laboratory of Earth Surface Processes and Resource Ecology College of Global Change and Earth System ScienceBeijing Normal University Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research PotsdamGermany

We analyze sea ice changes from eight different earth system models that have conducted experiment abrupt4xCO2 of the Coupled Model Intercomparison Project Phase 5 （CMIP5）. In response to abrupt quadrupling of CO2 from preindustrial levels, Arctic temperatures dramatically rise by about 10℃--16℃ in winter and the seasonal sea ice cycle and sea ice concentration are significantly changed compared with the pre-industrial control simulations （piControl）. Changes of Arctic sea ice concentration are spatially correlated with temperature patterns in all seasons and highest in autumn. Changes in sea ice are associated with changes in atmospheric circulation patterns at heights up to the jet stream. While the pattern of sea level pressure changes is generally similar to the surface air temperature change pattern, the wintertime 500 hPa circulation displays a positive Pacific North America （PNA） anomaly under abrupt4xCO2-piControl. This large scale teleconnection may contribute to, or feedback on, the simulated sea ice cover change and is associated with an intensification of the jet stream over East Asia and the north Pacific in winter.

关键词： Arctic sea ice atmospheric circulation ahrupt4xCO2

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波形钢腹板箱梁桥内衬混凝土构造尺寸的优化研究

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公路工程 2017年第6期42卷 31-35页

作者：崔学峰胡成合肥工业大学土木与水利工程学院安徽合肥230009

波形钢腹板箱梁桥在桥梁根部处通常设置有一定厚度的内衬混凝土与波形钢腹板共同承担截面剪力,但对内衬混凝土具体构造尺寸的研究尚不全面;依托实际工程为背景,通过对波形钢腹板箱梁桥进行ANSYS有限元数值模拟分析,研究内衬混凝土对波... 详细信息

波形钢腹板箱梁桥在桥梁根部处通常设置有一定厚度的内衬混凝土与波形钢腹板共同承担截面剪力,但对内衬混凝土具体构造尺寸的研究尚不全面;依托实际工程为背景,通过对波形钢腹板箱梁桥进行ANSYS有限元数值模拟分析,研究内衬混凝土对波形钢腹板受力性能的影响,并给出内衬混凝土构造尺寸的优化建议,包括内衬混凝土的长度,根部处最大厚度以及钢混结合段结束点处的最小厚度等,对以后的类似工程实践提供一些理论依据。

关键词：波形钢腹板内衬混凝土构造尺寸 ANSYS 优化

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Preliminary assessing no-surgical treatment response in bronchogenic carcinoma with three-phase contrast material-enhanced MRI

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The Chinese-German Journal of Clinical Oncology 2010年第8期9卷 444-447页

作者： Shenjiang Li xuefeng cui Debin Liu Wenjie Liang Yan Zhu Wenjie Bi Department of Imageology The Eighty-eighth Military Hospital Tai＇an 271000 China

Objective:The aim of this study was to evaluate the efficacy of three-phase contrast material-enhanced MRI in assessing no-surgical treatment response in peripheral bronchogenic carcinoma ***:Twenty-two patients with bronchogenic carcinoma after no-surgical treatment underwent three-phase contrast material-enhanced *** scans were obtained at 25 s,120 s and 180 s respectively after nonionic contrast material was administrated via the antecubital vein at a rate of 2 mL/s by using an *** and postcontrast signal intensity on every scan was *** Height(PH) and Maximum Enhancement(Emax) were *** pattern was evaluated on the images obtained at 120 s and 180 s after injection of contrast ***:Precontrast signal intensity,postcontrast signal intensity at 120 s and 180 s were 478 ± 108,926 ± 209 and 1050 ± ***(571 ± 225) and Emax(119 ± 49) of bronchogenic carcinoma after no-surgical treatment were significantly lower than those of bronchogenic carcinoma without any therapy(mean PH 655,mean Emax 150)(t = 2.178,P = 0.005 < 0.05,t = 4.196,P = 0.001 < 0.05).Six cases among 22 appeared homogeneous enhancement at 180 *** 120 s,there were 4 cases with inhomogeneous enhancement,1 case with homogeneous enhancement,1 case with peripheral enhancement among the 6 ***:Bronchogenic carcinoma after no-surgical treatment shows a gradual increase to the PH after administration of contrast ***-phase contrast material-enhanced MRI can reflect the blood supply of bronchogenic carcinoma and might be effective approach for evaluation of no-surgical treatment response in bronchogenic carcinoma.

关键词： bronchogenic carcinoma MRI image enhancement evaluation of curative effect

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