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Structural characterization,in vivo toxicity and biological activity of two new pyro-type diterpenoid alkaloids derived from 3-acetylaconitine

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Journal of Integrative Medicine 2023年第3期21卷 302-314页

作者： Yu-jie Wang Yan Wang pei tao School of Ethnic Medicine Chengdu University of Traditional Chinese MedicineChengdu 611137Sichuan ProvinceChina School of Pharmacy Chengdu University of Traditional Chinese MedicineChengdu 611137Sichuan ProvinceChina

Objective:The transformations that occur in diterpenoid alkaloids during the process of sand frying for Chinese herbal medicine preparation have yet to be *** study investigated the structural changes that take place in 3-acetylaconitine during a simulation of heat-processing and evaluated the toxicity and biological activity of the pyrolysis ***:The diterpenoid alkaloid 3-acetylaconitine was heated at 180°C for 15 min to simulate the process of sand *** pyrolysis products were separated using column chromatography,and their structures were investigated using high-resolution electrospray ionization mass spectroscopy and nuclear magnetic resonance ***,in vivo cardiotoxicity and acute toxicity of 3-acetylaconitine and its pyrolysis products were compared,and the aconitine-induced arrhythmia model was employed to evaluate the antiarrhythmic effect of the pyrolysis ***:Two new diterpenoid alkaloids,pyroacetylaconitine and 16-epi-pyroacetylaconitine,a pair of epimers at C-16,were *** comparing the structures of these compounds,possible transformation pathways were *** with the prototype compound,3-acetylaconitine,the cardiotoxicity and acute toxicity of the heat-transformed products were significantly *** the biological activity assay,the two pyrolysis products exhibited an effective increase in ventricular premature beat latency,a reduction in the occurrence of ventricular tachycardia,as well as an increase in the rate of arrhythmia inhibition,implying strong antiarrhythmic ***:Compared with 3-acetylaconitine,its pyrolysis products displayed lower toxicity and good antiarrhythmic effects;thus,they have potential for being developed into antiarrhythmic medicines.

关键词： 3-Acetylaconitine Acute toxicity Antiarrhythmic agents 16-Epi-pyroacetylaconitine Pyroacetylaconitine Processing

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Visualization and analysis of local and distant population flows on the Qinghai-Tibet Plateau using crowd-sourced data

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Journal of Geographical Sciences 2021年第2期31卷 231-244页

作者： XU Jun LIU Ju XU Yang pei tao State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchCASBeijing100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing100049China

Human migration between cities is one important aspect of spatial interaction that not only reflects urban attractiveness but also denotes interactions amongst *** therefore implemented a web-based visualization system to analyze and interactively explore local and distant population flow patterns between cities on the Qinghai-Tibet Plateau(QTP).We utilized 2017 Tencent population flow data from which we initially constructed inbound and outbound vectors for cities on the *** then used multidimensional scaling to examine and visualize migration patterns and similarities between *** reveal the presence of six local and three distant human mobility patterns on the QTP as well as average summer monthly migrations more than twice the level of those in the winter.

关键词： population flow visualization Tencent location big data spatiotemporal pattern Qinghai-Tibet Plateau

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Spatio-temporal characteristics of human activities using location big data in Qilian Mountain National Park

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International Journal of Digital Earth 2023年第1期16卷 3794-3809页

作者： Minglu Che Yanyun Nian Siwen Chen Hao Zhang tao pei Key Laboratory of Western China’s Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhouPeople’s Republic of China State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingPeople’s Republic of China University of Chinese Academy of Sciences BeijingPeople’s Republic of China

Human activities significantly impact the *** the patterns and distribution of these activities is crucial for ecological *** location-based technology advancement,big data such as location and trajectory data can be used to analyze human activities on finer temporal and spatial scales than traditional remote sensing *** this study,Qilian Mountain National Park(QMNP)was chosen as the research area,and Tencent location data were used to construct time series *** series clustering and decomposition were performed,and the spatio-temporal distribution characteristics of human activities in the study area were analyzed in conjunction with GPS trajectory data and land use *** study found two distinct human activity patterns,Pattern A and Pattern B,in *** to Pattern B,Pattern A had a higher volume of location data and clear nighttime *** incorporating land use and trajectory data,we conclude that Pattern A and Pattern B represent the activity patterns of the resident and tourist populations,***,the study identified seasonal variations in human activities,with human activity in summer being approximately two hours longer than in *** also conducted an analysis of human activities in different counties within the study area.

关键词： Location data spatial and temporal analysis time series clustering tourism studies social geography

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Investigation of Work Hardening Behavior of Inconel X-750 Alloy

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Acta Metallurgica Sinica(English Letters) 2017年第9期30卷 869-877页

作者： pei-tao Hua Wei-Hong Zhang Lin-Jie Huan Wen-Ru Sun Superalloys Division Institute of Metal Research ChineseAcademy of Sciences 110016 Shenyang China University of Chinese Academy of Sciences 100049 BeijingChina

The constant strain rate uniaxial compression tests were conducted in this paper for studying the work hardening behavior and revealing the underlying microstructure evolution involved in the plastic response of the nickel-based Inconel X-750 alloy. The work hardening rate versus true strain plots of Inconel X-750 alloy resembled that of low-stacking-fault energy （SFE） alloys with distinct four stages. The dislocations were found in the planar arrangements at a strain of 0.1 located at the onset of stage II, and the dislocation density was increased and the planar arrangement configuration was partially destroyed at a strain of 0.36 located in stage III. It was unexpected that deformation twins were observed at a strain of 0.69 located in stage IV although the alloy has been classified into materials with a higher SFE value. The result is different with a similar study, in which the deformation twins were absent in Ni-Cr-based alloy Inconel 625 even when the strain was as high as 0.65. It was deemed that the low level of solution strengthening favored the deformation of matrix and the activation of slip system for twining in Inconel X-750 alloy. Unlike the low-SFE alloys that the twins were always formed at the end of stage Ⅰ, the higher SFE delayed the twin formation to stage IV for Inconel X-750 alloy. The well- developed planar dislocation configuration gave rise to the stage Ⅱ with a slightly decreasing rate, the collapse of planar dislocation arrangements caused the occurrence of stage Ⅲ with an accelerated decreasing rate, and the twin formation led to the stage IV with a nearly constant work hardening rate.

关键词： Inconei X-750 alloy Work hardening behavior Planar dislocation arrangement Deformationtwins

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A systems dynamic model of a coal-based city with multiple adaptive scenarios： A case study of Ordos, China

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Science China Earth Sciences 2018年第3期61卷 302-316页

作者： LIU XiaoQian pei tao ZHOU ChengHu DU YunYan MA Ting XIE ChuanJie XU Jun College of Arts and Science of Beijing Union University Beijing 100191 China State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023 677ina

Abstract Cities based on coal resources have increasingly important social and economic roles in China. Their strategies for sustainable development, however, urgently need to be improved, which represents a huge challenge. Most observers believe that the continued progress of these cities relies on the optimization of scientific adaptive management in which social, economic, and ecological factors are incorporated. A systems perspective that combines policies, management priorities, and long-term policy impacts needs to be applied. To date, however, such an approach has not been adopted, which means it is difficult to implement adaptive management at the regional scale. In this study, we used various situations to develop a multiple adaptive scenario system dynamics model. We then simulated a range of policy scenarios, with Ordos in the Inner Mongolia Autonomous Region as a case study. Simulation results showed that the current strategy is not sustainable and predicted that the system would exceed the environmental capacity, with risks of resource exhaustion and urban decline in 2025-2035. Five critical policy variables, including the urban population carrying capacity, rates of water consumption and water recycling, and expansion of urban land cover, were identified during sensitivity analysis. We developed and compared six socio-economic scenarios. The urban area, represented by the urban population density, seemed to transition through five different stages, namely natural growth, rapid growth, stable oscillation, fading, and rebalancing. Our scenarios suggested that different policies had different roles through each stage. The water use efficiency management policy had a comprehensive far-reaching influence on the system behavior; land urbanization management functions dominated at the start, and population capacity management was a major control in the mid-term. Our results showed that the water recycling policy and the urban population carrying capacity were

关键词： System dynamics model Stella Resource-based city Multiple adaptive scenarios

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Quantitative estimates of collective geo-tagged human activities in response to typhoon Hato using location-aware big data

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International Journal of Digital Earth 2020年第9期13卷 1072-1092页

作者： Zhang Liu Yunyan Du Jiawei Yi Fuyuan Liang Ting Ma tao pei State Key Laboratory of Resources and Environmental Information System Institute of Geographical Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingPeople’s Republic of China College of Resources and Environment University of Chinese Academy of SciencesBeijingPeople’s Republic of China Department of Geography Western Illinois UniversityMacombILUSA

Location-aware big data from social media have been widely used to quantitatively characterize natural disasters and disaster-induced *** is not clear how human activities collectively respond to a *** this study,we examined the collective human activities in response to Typhoon Hato at multi spatial scales using aggregated location request *** proposed a Multilevel Abrupt Changes Detection(MACD)methodological framework to detect and characterize the abrupt changes in location requests in response to Typhoon *** show that,at the grid level,most anomaly grids were located within a radius of 53 km around the typhoon *** the city level,there are significant spatial difference in terms of the human activity recovery duration(230 h on average).At the subnational level,the absolute magnitude of abrupt location request changes is strongly correlated with the typhoon-induced economic losses and the population affected.

关键词： Human response typhoon natural disaster locationaware data rapid disaster assessment

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Changes in Organic Carbon and Nutrient Contents of Highly Productive Paddy Soils in Yujiang County of Jiangxi Province,China and Their Environmental Application

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Agricultural Sciences in China 2006年第7期5卷 522-529页

作者： LI Zhong-pei ZHANG tao-lin CHEN Bi-yun Institute of Soil Science the Chinese Academy of Sciences Nanjing 210008 P.R. China

Paddy field is an important land use in subtropical China. Development of high soil fertility and productivity is the management goal of paddy field, Fertilization and management practices have not only influenced the status of organic matter and nutrients in the soil but also affected the environmental quality. This article investigates the contents of organic carbon and the nutrients, and the change over the last 20 years in highly productive paddy soils and their environmental application. Field soils were sampled and the analytical results were compared with the corresponding values in the Second Soil Survey in Yujiang County of Jiangxi Province, China. The results showed that surface soils at a depth of 0-10 cm in highly productive paddy fields in Yujiang County of Jiangxi Province had contents of organic carbon （20.2 ±3.88） g kg^-1, total nitrogen （2.09±0.55） g kg^-1, and available phosphorus （42.7 ±32.7） mg kg^-1, respectively, which were all at very rich levels. Over the last 20 years, the organic carbon pool of the highly productive paddy soils reached a steady state. Total N and available P significantly increased, whereas available K changed a little. The amount and percentage of P immobilization in the surface soil （0-10 cm） of highly productive paddy fields were （142.7 ~ 41.1） mg kg-~ and （36.2~ 10.4）% of added P, and CEC （7.93 ~ 1.32） cmol kg-~. These two parameters were not higher than the mean values of paddy soils and upland red soils in the areas. Results also showed that fertilizer P in highly productive paddy soils had a high mobility and was prone to move toward a water body, which is the main source of nutrients causing eutrophication. Because of a weak K-fixing capacity, the available K content was not high in highly productive paddy soils. This suggests that attention should be paid to the K balance and the increase of soil K pool.

关键词： Yujiang County highly productive paddy soils organic C nutrients environmental application

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Mechanical properties and energy evolution of jointed rock specimens containing an opening under uniaxial loading

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International Journal of Minerals,Metallurgy and Materials 2021年第12期28卷 1875-1886页

作者： Peng Li Mei-feng Cai pei-tao Wang Qi-feng Guo Sheng-jun Miao Fen-hua Ren School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China Key Laboratory of High-Efficient Mining and Safety of Metal Mines(Ministry of Education of China) University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory of Urban Underground Space Engineering University of Science and Technology BeijingBeijing 100083China

To investigate the impact of an opening and joints with different inclination angles on the mechanical response behavior,the energy evolution characteristics,and distribution law of granite specimens,uniaxial loading tests were performed on the parallel jointed rock samples with an *** indicated an initial decreasing trend of the strength and deformation parameters,which later increases with increased inclination angle,reaching minimum values when the inclination angle is 45°.Evolution curves of the elastic strain energy and dissipated energy with strain of the samples showed step-like gradual mutation *** peak total energy,peak elastic strain energy,peak dissipated energy,and total input energy during the failure of the samples showed significant nonlinear characteristics with increasing inclination *** opening and joints as well as the change of the inclination angle had significant influences on the proportion of the elastic strain energy of the samples prior to the peak,resulting in the difference of the distribution law of input ***,the energy mechanism of the sample failure was *** showed that the energy release was the internal cause of the sudden destruction of the entire rock mass.

关键词： deformation energy rock

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Secure Network Coding Based on Lattice Signature

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China Communications 2014年第1期11卷 138-151页

作者： SHANG tao pei Hengli LIU Jianwei School of Electronic and Information Engineering Beihang University Beijing 100191 China

To provide a high-security guaran- tee to network coding and lower the comput- ing complexity induced by signature scheme, we take full advantage of homomorphic prop- erty to build lattice signature schemes and sec- ure network coding algorithms. Firstly, by means of the distance between the message and its sig- nature in a lattice, we propose a Distance-bas- ed Secure Network Coding （DSNC） algorithm and stipulate its security to a new hard problem Fixed Length Vector Problem （FLVP）, which is harder than Shortest Vector Problem （SVP） on lattices. Secondly, considering the bound- ary on the distance between the message and its signature, we further propose an efficient Bo- undary-based Secure Network Coding （BSNC） algorithm to reduce the computing complexity induced by square calculation in DSNC. Sim- ulation results and security analysis show that the proposed signature schemes have stronger unforgeability due to the natural property of lattices than traditional Rivest-Shamir-Adleman （RSA）-based signature scheme. DSNC algo- rithm is more secure and BSNC algorithm greatly reduces the time cost on computation.

关键词： secure network coding pollution attack lattice signature fixed length vector problem

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Disciplinary structure and development strategy of information geography in China

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Journal of Geographical Sciences 2022年第9期32卷 1670-1682页

作者： LI Xin YUAN Linwang pei tao HUANG Xin LIU Guang ZHENG Donghai State Key Laboratory of Tibetan Plateau Earth System Environment and ResourcesInstitute of Tibetan Plateau ResearchCASBeijing100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing100049China Ministry of Education Key Laboratory of Virtual Geographic Environment Nanjing Normal UniversityNanjing210023China State Key Laboratory of Resources and Environment Information System Institute of Geographic Sciences and Natural Resources ResearchCASBeijing100101China School of Remote Sensing and Information Engineering Wuhan UniversityWuhan430079China Key Laboratory of Digital Earth Science Aerospace Information Research InstituteCASBeijing100094China

The advent of the information era has resulted in exceptional advances in geographic *** domain of geographic science has expanded from traditional physical and human geography to physical,human,and information geography,resulting in the emergence of the field of information *** subdisciplines have gradually formed,i.e.,geographic remote sensing science,geographic information science,and geographic data *** a view towards preparing a description of the disciplinary structure of geographic science for the“Development Strategy of Discipline and Frontier Research in China(2021-2035)”,this article summarizes the history,definition,and disciplinary structure of information *** strategic layout of the discipline,along with the goals and key directions of priority development fields,are also *** insights into this new discipline provided in this paper will promote the development and application of remote sensing and geographic information within the framework of geographic science,advancing the synthesis of geographic research and the integrated development of geographic science.

关键词： information geography geographic remote sensing science geographic information science geographic data science disciplinary structure

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