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Vegetation Index Reconstruction and linkage with Drought for the Source Region of the Yangtze River Based on Tree-ring Data

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Chinese Geographical Science 2021年第4期31卷 684-695页

作者： li jinjian WANG Shu QIN Ningsheng liU Xisheng JIN liya School of Atmospheric Sciences Plateau Atmosphere and Environment Key Laboratory of Sichuan ProvinceChengdu University of Information TechnologyChengdu 610225China Institute of Plateau Meteorology China Meteorological AdministrationChengdu/Heavy Rain and Drought-Flood Disasters in Plateau and BasinKey Laboratory of Sichuan ProvinceChengdu 610072China Hydrology and Water Resources Bureau of Qinghai Province Xining 810000China

Variations in vegetation are closely related to climate change, but understanding of their characteristics and causes remains limited. As a typical semi-humid and semi-arid cold plateau region, it is important to understand the knowledge of long term Normalized Difference Vegetation Index(NDVI) variations and find the potential causes in the source region of the Yangtze River. Based on four tree-ring width chronologies, the regional mean NDVI for July and August spanning the period 1665–2013 was reconstructed using a regression model, and it explained 43.9% of the total variance during the period 1981–2013. In decadal, the reconstructed NDVI showed eight growth stages(1754–1764, 1766–1783, 1794–1811, 1828–1838, 1843–1855, 1862–1873, 1897–1909, and 1932–1945)and four degradation stages(1679–1698, 1726–1753, 1910–1923, and 1988–2000). And based on wavelet analysis, significant cycles of2–3 yr and 3–8 yr were identified. In additional, there was a significant positive correlation between the NDVI and the Palmer Drought Severity Index(PDSI) during the past 349 yr, and they were mainly in phase. However, according to the results of correlation analysis between different grades of drought/wet and NDVI, there was significant asymmetry in extreme drought years and extreme wet years. In extreme drought years, NDVI was positively correlated with PDSI, and in extreme wet years they were negatively correlated.

关键词： Normalized Difference Vegetation Index(NDVI) reconstruction dendrochronology tree ring Source Region of the Yangtze River

Detecting the spatial-temporal pattern of moisture evolution on the Tibetan Plateau during the Holocene by model-proxy comparison

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Frontiers of Earth Science 2023年第4期17卷 981-996页

作者： Zeyu ZHENG liya JIN jinjian li Xiaojian ZHANG Jie CHEN MOE Key Laboratory of Western China’s Environmental System College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China School of Atmospheric Sciences Chengdu University of Information TechnologyChengdu 610225China School of Geographic and Oceanographic Sciences Nanjing UniversityNanjing 210023China

The Tibetan Plateau(TP)is a key region for environmental and climatic research due to its significant linkages with large-scale atmospheric *** the long-term moisture evolution pattern and its forcing mechanisms on the TP during the Holocene may provide insights into the interaction between low-latitude climate systems and midlatitude ***,we synthesized 27 paleoclimate proxy records covering the past 9500 *** results of the rotated empirical orthogonal function analysis of the moisture variation revealed spatial-temporal heterogeneity,which was classified into 5 *** records were then compared with the results from the Kiel Climate Model and other *** results showed that moisture evolution on the western-southern-central TP was controlled by the Indian summer monsoon(ISM).On the south-eastern TP,moisture change was affected by the interplay between the East Asian summer monsoon(EASM)and the westerlies,as well as the *** diverse patterns of circulation system precipitation,moisture changes recorded in the paleorecords showed spatial-temporal discrepancies,especially during the early to middle ***,given the anti-phase pattern of summer precipitation in the EASM area under El Nino/Southern Oscillation(ENSO)conditions and the unstable relationship between the ISM and ENSO,it is reasonable to conclude that relatively strong ENSO variability during the late Holocene has contributed to these discrepancies as Asian summer monsoon precipitation has declined.

关键词： Tibetan Plateau Holocene moisture evolution model-proxy comparison

Analysis of the temporal and spatial distribution of water quality in China＇s major river basins, and trends between 2005 and 2010

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Frontiers of Earth Science 2015年第3期9卷 463-472页

作者： jinjian li Xiaojie MENG Yan ZHANG Juan li linlin XIA Hongmei ZHENG State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Beijing Normal University Beijing 100875 China Chinese Research Academy of Environmental Sciences Beijing 100012 China

In this study, based on environmental quality monitoring data on 22 pollutants from 490 control sections, we analyzed the spatial distribution and temporal changes of water quality in ten Chinese river basins （watersheds） to reveal the trends from 2005 to 2010. We used a comprehensive water pollution index （WPI） and the proportions of this index accounted for by the three major pollutants to analyze how economic development has influenced water quality. Higher values of the index represent more serious pollution. We found that WPI was much higher for the Hai River Basin （1.83 to 5.60 times the averages in other regions）. In the Yangtze River Basin, WPI increased from upstream to downstream. The indices of some provinces toward the middle of a basin, such as Hebei Province in the Hal River Basin, Shanxi Province in the Yellow River Basin, and Anhui Province in the Huai River Basin, were higher than those of upstream and downstream provinces. In the Songhua, liao, and South- east river basins, WPI decreased during the study period： in 2010, it decreased by 33.9%, 44.3%, and 67.2%, respectively, compared with the 2005 value. In the Pearl River, Southwest, and Inland river basins, WPI increased by 23.1%, 47.7%, and 38.5% in 2010, compared with 2005. A comparison of WPI with the GDP of each province showed that the water pollution generated by economic development was lightest in northwestern, southwestern, and northeastern China, and highest in central and eastern China, and that the water environment in some coastal regions were improving. However, some provinces （e.g., Shanxi Province） were seriously polluted.

关键词： water environment temporal changes spatial

Pd-Catalyzed Synthesis of a-Awl Vinylphosphonates via Suzuki Arylation of a-Phosphonovinyl Nonaflates

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Chinese Journal of Chemistry 2015年第10期33卷 1119-1123页

作者： Meijuan Yuan Yewen Fang li Zhang Xiaoping Jin Minjia Tao Qilin Ye Ruifeng li jinjian li Hui Zheng Juejun Gu College of Chemistry and Chemical Engineering Taiyuan University of Technology Taiyuan Shanxi 030024 China Department of Biology and Pharmaceutical Sciences Zhejiang Pharmaceutical College Ningbo Zhejiang 315100 China School of Chemical Engineering Ningbo University of Technology Ningbo Zhejiang 315016 China

The first palladium-catalyzed method for the arylation of α-phosphonovinyl nonaflates is described. Using a catalyst comprised of Pd（OAc）2 and SPhos, terminal and internal α-aryl vinylphosphonates could be efficiently ac- cessed under mild conditions. The reaction features a broad coupling partner scope and tolerates many functional groups.

关键词： phosphonate cross-coupling palladium catalysis arylation

Bi-direction and flexible multi-mode morphing wing based on antagonistic SMA wire actuators

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Chinese Journal of Aeronautics 2024年第12期37卷 373-387页

作者： Jiannan YANG Yahui ZHANG Xiaojun GU jinjian li Pingchu FANG Xinru YANG Jun WANG Jihong ZHU Weihong ZHANG State IJR Center of Aerospace Design and Additive Manufacturing Northwestern Polytechnical UniversityXi’an 710072China MIIT Lab of Metal Additive Manufacturing and Innovative Design Northwestern Polytechnical UniversityXi’an 710072China National Key Laboratory of Unmanned Aerial Vehicle Technology Northwestern Polytechnical UniversityXi’an 710072China Integrated Research and Development Platform of Unmanned Aerial Vehicle Technology Northwestern Polytechnical UniversityXi’an 710072China

This work evaluates the viability of a cutting-edge flexible wing prototype actuated by Shape Memory Alloy(SMA)wire *** flexible wings have garnered significant interest for their potential to enhance aerodynamic efficiency by mitigating noise and delaying flow *** actuators are particularly advantageous due to their superior power-to-weight ratio and adaptive response,making them increasingly favored in morphing aircraft *** methodology begins with a detailed delineation of the fishbone camber morphing wing rib structure,followed by the construction of a multi-mode morphing wing segment through 3D-printed rib *** testing of the SMA wire actuators’actuation capacity and efficiency was conducted to establish their operational *** experimental analyses focused on the bi-directional and reciprocating morphing performance of the fishbone wing rib,which incorporates SMA wires on the upper and lower *** experiments confirmed the segment’s multi-mode morphing *** assessments have demonstrated that our design substantially improves the lift-to-Drag ratio(L/D)when compared to conventional rigid ***,two phases of flight tests demonstrated the feasibility of SMA as an aircraft actuator and the validity of flexible wing structures to adjust the aircraft attitude,respectively.

关键词： Morphing aircraft Smart materials Flexible structures 3D-printing Multi-mode morphing

Identification of a natural PLA2 inhibitor from the marine fungus Aspergillus sp.c1 for MAFLD treatment that suppressed lipotoxicity by inhibiting the IRE-1a/XBP-1s axis and JNK signaling

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Acta Pharmaceutica Sinica B 2024年第1期14卷 304-318页

作者： Yong Rao Rui Su Chenyan Wu Xingxing Chai jinjian li Guanyu Yang Junjie Wu Tingting Fu Zhongping Jiang Zhikai Guo Congjun Xu ling Huang Key Laboratory of Tropical Biological Resources of Ministry of Education School of Pharmaceutical SciencesHainan UniversityHaikou 570200China Hainan Key Laboratory of Tropical Microbe Resources Institute of Tropical Bioscience and BiotechnologyChinese Academy of Tropical Agricultural Sciences&Key Laboratory for Biology and Genetic Resources of Tropical Crops of Hainan ProvinceHainan Institute for Tropical Agricultural ResourcesHaikou 571101China School of Pharmaceutical Sciences Guangdong Provincial Key Laboratory of New Drug Design and EvaluationSun Yat-sen UniversityGuangzhou 510275China Laboratory Animal Center of Guangdong Medical University Dongguan 523808China

lipotoxicity is a pivotal factor that initiates and exacerbates liver injury and is involved in the development of metabolic-associated fatty liver disease(MAFLD).However,there are few reported lipotoxicity ***,we identified a natural anti-lipotoxicity candidate,HN-001,from the marine fungus Aspergillus ***-001 dose-and time-dependently reversed palmitic acid(PA)-induced hepatocyte *** protection was associated with IRE-1a-mediated XBP-1 splicing inhibition,which resulted in suppression of XBP-1s nuclear translocation and transcriptional *** of XBP-1s attenuated lipotoxicity,but no additional ameliorative effect of HN-001 on lipotoxicity was observed in XBP-1s knockdown ***,the ER stress and lipotoxicity amelioration was associated with *** HN-001 and the PLA2 inhibitor MAFP inhibited PLA2 activity,reduced lysophosphatidylcholine(LPC)level,subsequently ameliorated *** contrast,overexpression of PLA2 caused exacerbation of lipotoxicity and weakened the anti-lipotoxic effects of ***,HN-001 treatment suppressed the downstream pro-apoptotic JNK *** vivo,chronic administration of HN-001(i.p.)in mice alleviated all manifestations of MAFLD,including hepatic steatosis,liver injury,inflammation,and *** effects were correlated with PLA2/IRE-1a/XBP-1s axis and JNK signaling *** data indicate that HN-001 has therapeutic potential for MAFLD because it suppresses lipotoxicity,and provide a natural structural basis for developing anti-MAFLD candidates.

关键词： lipotoxicity MAFLD ER stress IRE-1a XBP-1s JNK PLA2

Neuroprotective effect of Naochuxue prescription(脑出血方)on intracerebral hemorrhage:inhibition of autophagy via downregulating high mobility group box-1

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Journal of Traditional Chinese Medicine 2024年第5期44卷 944-953页

作者： JIN Hong WANG Xinna WANG Ruonan li jinjian YU Junchao ZHAO Dexi ZHAI Lu College of Chinese medicine Changchun University of Chinese MedicineChangchun 13000China Department of Encephalopathy the Affiliated Hospital of Changchun University of Chinese MedicineChangchun 13000China College of nursing Changchun University of Chinese MedicineChangchun 13000China Research Center of Traditional Chinese Medicine the First Affiliated Hospital of Changchun University of Chinese MedicineChangchun 13000China

OBJECTIVE:To determine the molecular mechanisms underlying the neuroprotective effects of Naochuxue prescription(脑出血方,NCXP)in rats with intracerebral hemorrhage(ICH).METHODS:Sprague–Dawley rats were injected with collagenase to generate ICH models,which were then randomly divided into six groups,including control,sham,model,and three intervention *** intervention groups received different doses of NCXP(0.13,0.26,and 0.52 g/kg)daily for 10 ***-performance liquid chromatography(HPLC)was used to analyze the chemical characteristics of *** neurobehavioral outcomes of the rats were evaluated using neurological deficit scores(Zea Longa 5)and the corner turn *** changes in perihematomal tissues after ICH were observed using hematoxylin and eosin ***(IHC)was used to detect the inflammation expression of interleukin 6(IL-6)and toll-like receptor 4(TLR4).High mobility group box-1(HMGB1),Beclin1,microtubule-associated protein 1 light chain 3 beta(LC3),and sequestosome 1(p62)were detected using real-time quantitative polymerase chain reaction and Western blotting in perihematomal ***:HPLC showed that the NCXP had good *** with ICH had severe neurological function deficits compared to the control *** results showed that NCXP significantly downregulated the expression of the inflammatory proteins IL-6 and *** rats treated with NCXP showed less neurological injury than the model group,accompanied by a significantly decreased expression of HMGB1,Beclin1,and LC3 and an increased expression of ***:The neuroprotective effect of NCXP alleviated inflammation and autophagy possibly by downregulating HMGB1 ***,further research on the signaling pathways is required to verify this hypothesis.

关键词： intracerebral hemorrhage HMGB proteins inflammation autophagy Naochuxue prescription

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高校图书馆科学数据服务研究现状与趋势分析

图书馆工作与研究 2019年第12期 86-91页

作者：李金建河南工业职业技术学院

利用文献分析法,以中国知识资源总库(CNKI)发表的高校图书馆科学数据服务研究文献为研究对象,系统总结、归纳现有研究成果,根据高校图书馆科学数据服务研究概况,指出未来研究应探索高校图书馆科学数据技术型服务与咨询型服务的融合发展... 详细信息

利用文献分析法,以中国知识资源总库(CNKI)发表的高校图书馆科学数据服务研究文献为研究对象,系统总结、归纳现有研究成果,根据高校图书馆科学数据服务研究概况,指出未来研究应探索高校图书馆科学数据技术型服务与咨询型服务的融合发展,拓展科学数据服务内容,丰富科学数据服务研究方法等。

关键词：高校图书馆科学数据服务科学数据管理

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事件相机驱动的空间机械臂视觉伺服

空间控制技术与应用 2023年第3期49卷 28-35页

作者：李金健胡权北京理工大学北京100090

针对空间机械臂携带的传统视觉系统面临图像数据量大、测量延迟高等问题,研究了基于事件相机驱动的空间机械臂视觉伺服控制方法.事件相机是一种低延迟的新型神经形态视觉传感器,具有超高时间分辨率和高动态范围,但其产生的异步事件流数... 详细信息

针对空间机械臂携带的传统视觉系统面临图像数据量大、测量延迟高等问题,研究了基于事件相机驱动的空间机械臂视觉伺服控制方法.事件相机是一种低延迟的新型神经形态视觉传感器,具有超高时间分辨率和高动态范围,但其产生的异步事件流数据与传统相机完全不同,需要设计新的算法以适配事件流数据.基于迭代重加权拟合设计了适用于事件流数据的快速圆形特征检测与跟踪算法;发展了适配圆形特征的空间机械臂视觉伺服方法.实验表明提出的检测与跟踪算法在实现高跟踪成功率的同时还具有远超传统视觉算法的检测速度,此外从事件相机获得的高速特征反馈能够驱动机械臂完成更加精确的伺服运动.

关键词：事件相机空间机械臂视觉伺服特征检测与跟踪