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Vegetation Change of Ecotone in West of Northeast China Plain Using Time-series Remote Sensing Data

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Chinese Geographical Science 2010年第2期20卷 167-175页

作者： huang Fang WANG ping School of Urban and Environmental Sciences Northeast Normal University Changchun 130024 China

Multi-temporal series of satellite SPOT-VEGETATION normalized difference vegetation index (NDVI) and normalized difference water index (NDWI) data from 1998 to 2007 were used for analyzing vegetation change of the ecotone in the west of the Northeast China Plain. The yearly and monthly maximal values,anomalies and change rates of NDVI and NDWI were calculated to reveal the interannual and seasonal changes in vegetation cover and vegetation water content. Linear regression method was adopted to characterize the trends in vegetation change. The yearly maximal NDVI decreased from 0.41 in 1998 to 0.37 in 2007,implying the decreasing trend of vegetation activity. There was a significant decrease of maximal NDVI in spring and summer over the study period,while an increase trend was observed in autumn. The vegetation-improved regions and vegetation-degraded regions occupied 17.03% and 20.30% of the study area,respectively. The maximal NDWI over growing season dropped by 0.027 in 1998–2007,and about 15.15% of the study area showed a decreasing trend of water content. Vegetation water stress in autumn was better than that in spring. Vegetation cover and water content variations were sensitive to annual precipitation,autumn precipitation and summer temperature. The vegetation degradation trend in this ecotone might be induced by the warm-drying climate especially continuous spring and summer drought in the recent ten years.

关键词： vegetation change normalized difference vegetation index (NDVI) normalized difference water index (NDWI) SPOT-VEGETATION ecotone Northeast China Plain

Correlation between crystal structure and mechanical performance of Cr-implanted 300M high-strength steel using X-ray diffraction method

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Journal of Iron and Steel Research International 2019年第10期26卷 1106-1116页

作者： Xiao-hu Chen ping-ze Zhang Dong-bo Wei Xiao huang Feng Ding Feng-kun Li Xian-jun Dai Zhang-zhong Wang College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106JiangsuChina Ningbo Branch China Ordnance AcademyNingbo 315103ZhejiangChina Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology Nanjing 211167JiangsuChina Key Laboratory of Materials Preparation and Protection for Harsh Environment(Nanjing University of Aeronautics and Astronautics) Ministry of Industry and Information TechnologyNanjing 211106JiangsuChina Department of Mechanical and Aerospace Engineering Carleton UniversityOttawaON ONK1S5B6Canada

In order to study the influence of crystal structure change due to implantation dose on the hardness and wear performance of 300M high-strength steel,samples were surface modified by Cr implantation with dosages of 5.0 × 10^16,1.5 × 10^17 and 3.0 × 10^17 ions/cm^2.X-ray diffraction method,which was already applied in studies on the microstructure of deformed and heat-treated materials,was used to study the crystal structure of the implanted steel,and the results were corrected with the hardness and wear *** solid solution strengthening effect and microstructure vary with increase in implantation *** to strong solid solution hardening of Cr,small average crystallite size and high dislocation density,the hardness and wear resistance of implanted steel with dose of 5.0 × 10^16 ions/cm^2 were found to be the highest compared with other ***,although the crystal lite size of the implanted sample with dose of 3 × 10^17 ions/cm^2 was similar to that of substrate and the dislocation density was lower than that of the substrate,its higher hardness and lower specific wear rate were due to the solid solution hardening and perhaps Cr clusters reinforcement.

关键词： X-ray diffraction method Ion implantation Dislocation density Hardness Wear Crystal structure

Berberine retarded the growth of gastric cancer xenograft tumors by targeting hepatocyte nuclear factor 4α

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World Journal of Gastrointestinal Oncology 2022年第4期14卷 842-857页

作者： Ling-Li Li ze Peng Qian Hu Li-Jun Xu Xin Zou Dong-Mei huang ping Yi Department of Integrated Traditional Chinese and Western Medicine Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430045Hubei ProvinceChina Department of Integrated Traditional Chinese and Western Medicine West China Hospital of Sichuan UniversityChengdu 610041Sichuan ProvinceChina

BACKGROUND Gastric cancer is the third deadliest cancer in the world and ranks second in incidence and mortality of cancers in *** advances in prevention,diagnosis,and therapy,the absolute number of cases is increasing every year due to aging and the growth of high-risk populations,and gastric cancer is still a leading cause of cancer-related *** cancer is a consequence of the complex interaction of microbial agents,with environmental and host factors,resulting in the dysregulation of multiple oncogenic and tumor-suppressing signaling *** efforts have been made to investigate in detail the genomic and epigenomic heterogeneity of this disease,resulting in the identification of new specific and sensitive predictive and prognostic ***,a monoclonal antibody against the HER2 receptor,is approved in the first-line treatment of patients with HER2+tumors,which accounts for 13%-23%of the gastric cancer ***,a monoclonal antibody against VEGFR2,is currently recommended in patients progressing after first-line *** clinical trials have also tested novel agents for advanced gastric cancer but mostly with dis-appointing results,such as anti-EGFR and anti-MET monoclonal ***,it is still of great significance to screen specific molecular targets for gastric cancer and drugs directed against the molecular *** To investigate the effect and mechanism of berberine against tumor growth in gastric cancer xenograft models and to explore the role of hepatocyte nuclear factor 4α(HNF4α)-WNT5a/β-catenin pathways played in the antitumor effects of *** MGC803 and SGC7901 subcutaneous xenograft models were *** control group was intragastrically administrated with normal saline,and the berberine group was administrated intragastrically with 100 mg/kg/d *** body weight of nude mice during the experiment was measured to assess whether berberine has any adver

关键词： Berberine Gastric cancer Xenograft models Hepatocyte nuclear factor 4α WNT5a

Recent progress on low dimensional perovskite solar cells

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Journal of Energy Chemistry 2018年第4期27卷 1091-1100页

作者： Lingfeng Chao ze Wang Yingdong Xia Yonghua Chen Wei huang Key Laboratory of Flexible Electronics(KLOFE)&Institution of Advanced Materials(IAM) Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)Nanjing Teeh University(NanjingTech)Nanjing 211816Jiangsu.China Shaanxi Institute of Flexible Electronics(SIFE).Northwestern Polytechnical University(NPU) Xi'an 710072ShaanxiChina Key Laboratory for Organic Electronics&Information Displays(KLOEID) and Institute of Advanced Materials(IAM).Nanjing University of Posts and TelecommunicationsNanjing 210023JiangsuChina

Low dimensional perovskites have recently attracted much attention due to their vertical growth of crys- talline orientation, excellent film morphology, and long-term humidity, light, and heat stability, How- ever, low dimensional perovskites suffer fl＇om low power conversion efficiency （PCE） with respect to their three dimensional analogues. Therefore, it is imperative to find excellent low-dimensional perovskite materials for improving the PCE. Previous work has demonstrated that bulkier organic molecules, e,g., C6Hs（CH2）2NH3＋（PEA＋）, CH3（CH2）3NH3＋（n-BAT, iso-BA＋）, C2H4NH3 ＋, and polyethylenimine cations （PEI＋）, play an important role in the formation of low-dimensional perovskites. In this review, we review the recent development of low dimensional perovskites for solar cells application in terms of film preparation, photophysics, and stability of perovskites, as well as the related device structure and physics. We have also discussed the future development of low-dimensional perovskites from materials design, fabri- cation processes, and device structure.

关键词： Low dimensional perovskites Perovskite solar cells Stability Bulkier organic molecules

In-situ fabrication of Mo6S6-nanowire-terminated edges in monolayer molybdenum disulfide

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Nano Research 2018年第11期11卷 5849-5857页

作者： Wei huang Xiaowei Wang Xujing Ji ze Zhang Chuanhong Jin State Key Laboratory of Silicon Materials School of Materials Science and Engineering Zhejiang University Hangzhou 310027 China

Edge structures are highly relevant to the electronic, magnetic, and catalytic properties of two-dimensional (2D) transition metal dichalcogenides (TMDs) and their one-dimensional (1D) counterparts, i.e., nanoribbons, and should be precisely tailored for the desired application. In this work, we report the formation of novel Mo6S6 nanowire (NW)-terminated edges in monolayer molybdenum disulfide (MoS2) via an e-beam irradiation process combined with high temperature heating. The atomic structures of the NW-terminated edges and the dynamic formation process were observed experimentally using scanning transmission electron microscopy. Further analysis showed that the NW-terminated edge could be formed on both the Mo-zigzag (ZZ) edge and S-ZZ edge and could exhibit a stability superior to that of the pristine ZZ and armchair (AC) edges. In addition, analogous edge structures could also be formed in MoS2 nanoribbons and other TMD materials such as MoxW1-xSe2. We believe that these novel edge structures may impart novel properties to the 2D and 1D TMD materials and provide new opportunities for their applications in catalytic, spintronic, and electronic devices.

关键词： mdybdenum disulfide (MoS2) transition metal dichalcogenides nanowire edge structure in-situ

Multiscale spatiotemporal meteorological drought prediction:A deep learning approach

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Advances in Climate Change Research 2024年第2期15卷 211-221页

作者： Jia-Li ZHANG Xiao-Meng huang Yu-ze SUN Department of Earth System Science Ministry of Education Key Laboratory for Earth System ModellingInstitute for Global Change StudiesTsinghua UniversityBeijing 100084China

Reliable monitoring and thorough spatiotemporal prediction of meteorological drought are crucial for early warning and decision-making regarding drought-related *** utilisation of multiscale methods is effective for a comprehensive evaluation of drought occurrence and progression,given the complex nature of meteorological ***,the nonlinear spatiotemporal features of meteorological droughts,influenced by various climatological,physical and environmental factors,pose significant challenges to integrated prediction that considers multiple indicators and time *** address these constraints,we introduce an innovative deep learning framework based on the shifted window transformer,designed for executing spatiotemporal prediction of meteorological drought across multiple *** formulate four prediction indicators using the standardized precipitation index and the standard precipitation evaporation index as core methods for drought definition using the ERA5 reanalysis *** indicators span time scales of approximately 30 d and one ***-term indicators capture more anomalous variations,whereas long-term indicators attain comparatively higher accuracy in predicting future *** focus on the East Asian region,notable for its diverse climate conditions and intricate terrains,to validate the model's efficacy in addressing the complexities of nonlinear spatiotemporal *** model's performance is evaluated from diverse spatiotemporal viewpoints,and practical application values are analysed by representative drought *** results substantiate the effectiveness of our proposed model in providing accurate multiscale predictions and capturing the spatiotemporal evolution characteristics of *** of the four drought indicators accurately delineates specific facets of the meteorological drought ***,three representative drought events,namely flash drought,sustained drought and severe drought,

关键词： Meteorological drought Spatiotemporal prediction Multiscale Swim transformer Deep learning

Photoinduced radical sulfur dioxide insertion with asymmetric cyclization of alkenes: accessing β-chiral sulfones bearing S-stereocentric cyclic sulfinamides

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Science China Chemistry 2025年第01期 257-263页

作者： Jiapian huang Chenxin Wang Xu Wang Xiaoyu Zhou Wei Xiao Jie Wu School of Pharmaceutical and Chemical Engineering & Institute for Advanced Studies Taizhou University State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences School of Chemistry and Chemical Engineering Henan Normal University

The generation of various β-chiral sulfones bearing chiral cyclic sulfinamides through photoredox-catalyzed sulfur dioxide insertion with asymmetric radical cyclization is described. This method features a broad substrate scope and excellent stereospecificity. Computational studies reveal that the dispersion interaction between sulfinyl group and CH2SO2Ph group plays a crucial role in the stereoselectivity control.

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Elevational and temporal patterns of pollination success in distylous and homostylous buckwheats(Fagopyrum)in the Hengduan Mountains

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Plant Diversity 2024年第5期46卷 661-670页

作者： Ling-Yun Wu Shuang-Quan huang ze-Yu Tong Faculty of Resources and Environmental Science Hubei UniversityWuhan 430062China Institute of Evolution and Ecology School of Life SciencesCentral China Normal UniversityWuhan 430079China

Reproductive strategies of sexually dimorphic plants vary in response to the ***,we ask whether the sexual systems of Fagopyrum species(i.e.,selfing homostylous and out-crossing distylous)represent distinct adaptive strategies to increase reproductive success in changing alpine *** answer this question,we determined how spatial and temporal factors(e.g.,elevation and peak flowering time)affect reproductive success(i.e.,stigmatic pollen load)in nine wild Fagopyrum species(seven distylous and two homostylous)among 28 populations along an elevation gradient of 1299-3315 m in the Hengduan Mountains,southwestern *** also observed pollinators and conducted hundreds of hand pollinations to investigate inter/intra-morph compatibility,self-compatibility and pollen limitation in four Fagopyrum species(two distylous and two homostylous).We found that Fagopyrum species at higher elevation generally had bigger flowers and more stigmatic pollen loads;lateflowering individuals had smaller flowers and lower pollen *** pollen deposition was more variable in distylous species than in homostylous *** seed set was not pollenlimited in all species,we found that fruit set was much lower in distylous species,which rely on frequent pollinator visits,than in homostylous species capable of autonomous *** findings that pollination success increases at high elevations and decreases during the flowering season suggest that distylous and homostylous species have spatially and temporally distinct reproductive strategies related to environment-dependent pollinator activity.

关键词： Biodiversity hotspot Elevation gradient Fagopyrum Stigmatic pollen load Temporal pattern

DNA damage repair:historical perspectives,mechanistic pathways and clinical translation for targeted cancer therapy

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Signal Transduction and Targeted Therapy 2021年第8期6卷 2391-2425页

作者： Ruixue huang ping-Kun Zhou Department of Occupational and Environmental Health Xiangya School of Public HealthCentral South UniversityChangshaHunanChina Department of Radiation Biology Beijing Key Laboratory for RadiobiologyBeijing Institute of Radiation MedicineAMMSBeijingChina

Genomic instability is the hallmark of various cancers with the increasing accumulation of DNA *** application of radiotherapy and chemotherapy in cancer treatment is typically based on this property of ***,the adverse effects including normal tissues injury are also accompanied by the radiotherapy and *** cancer therapy has the potential to suppress cancer cells'DNA damage response through tailoring therapy to cancer patients lacking specific DNA damage response ***,understanding the broader role of DNA damage repair in cancers has became a basic and attractive strategy for targeted cancer therapy,in particular,raising novel hypothesis or theory in this field on the basis of previous scientists'findings would be important for future promising druggable emerging *** this review,we first illustrate the timeline steps for the understanding the roles of DNA damage repair in the promotion of cancer and cancer therapy developed,then we summarize the mechanisms regarding DNA damage repair associated with targeted cancer therapy,highlighting the specific proteins behind targeting DNA damage repair that initiate functioning abnormally duo to extrinsic harm by environmental DNA damage factors,also,the DNA damage baseline drift leads to the harmful intrinsic targeted cancer *** addition,clinical therapeutic drugs for DNA damage and repair including therapeutic effects,as well as the strategy and scheme of relative clinical trials were intensive *** on this background,we suggest two hypotheses,namely"environmental gear selection”to describe DNA damage repair pathway evolution,and"DNA damage baseline drift”,which may play a magnified role in mediating repair during cancer *** two new hypothesis would shed new light on targeted cancer therapy,provide a much better or more comprehensive holistic view and also promote the development of new research direction and new overcoming strategies for

关键词： damage clinical targeted