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Land cover changes based on plant successions: Deforestation, rehabilitation and degeneration of forest in the upper Dadu River watershed

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Science china Earth sciences 2005年第12期48卷 2214-2230页

作者： YAN Jianzhong1,2,3. zhang Yili1, BAI Wanqi1, LIU Yanhua4, BAO Weikai5, LIU Linshan1, 2 & ZHENG Du1 1. Institute of Geographic sciences and Natural Resources Research, Chinese Academy of sciences, {3. 100101, china 2. Graduate school of the Chinese Academy of sciences, {3. 10003., china 3. College of Resources and Environment, Southwest Agricultural university, Chongqing 400716, china 4. The Ministry of Science and Technology, P. C. china, {3. 100862, china 5. Chengdu Institute of Biology, Chinese Academy of sciences, Chengdu 610041, china 1. Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Graduate school of the Chinese Academy of sciences 100039 Beijing China 3. College of Resources and Environment Southwest Agricultural University 400716 Chongqing China 4. The Ministry of Science and Technology P. C. China 100862 Beijing China 5. Chengdu Institute of Biology Chinese Academy of Sciences 610041 Chengdu China

To link regional land use/cover changes with environmental effects, land cover changes are required to reflect vegetation successions, whereas the land cover classification systems commonly used nowadays cannot serve this purpose. In this paper, a new land cover classification system is established in which land covers are classified by the vegetation succes-sions, taking Zamtang County, Barkam County and Jinchuan County in the upper Dadu River watershed as a study area. Using multi-temporal remote sensing images, the land cover data of 1967, 1986 and 2000 are obtained by means of integration of unsupervised classification and visual interpretation methods. The database facilitates the study of land use/cover changes, en-vironmental effects and ecological construction. Land cover changes reflect the main ecological processes in the upper Dadu River watershed. The landscape composed mainly of grasslands, wildwoods and alpine scrubs in 1967 was changed to that of grasslands, secondary forests, al-pine scrubs, fragmentary wildwoods, artificial forests, secondary scrubs in 2000, meanwhile, the landscape got more fragmentized. The total area of the forests decreased by 9.43.. Study results have shown the process of restoration of logged areas in forest centers. From 1967 to 2000, only 6.86 percents of logged areas were converted to shrubs, meadows or crop-lands, and the rest were converted into artificial forests or secondary forests. So the ecological shelter functions will be restored, stage by stage. Firewood collection, charcoal production and overgrazing are the three major triggers for the extensive degradation of alpine oak forests, Sa-bina tibetica forests and meadows. The arid valley grasslands expanded too. The degradation of vegetation in the southern slopes impairs ecological shelter functions and affects livelihood of local residents, so it is essential to find effective measures for ecological restoration and recon-struction. Field investigations have found

关键词： land use/cover classification, upper Dadu River watershed, vegetation successions, GIS, RS.

Ferroptosis regulating lipid peroxidation metabolism in the occurrence and development of gastric cancer

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2781-2792页

作者： Lan-mei Wang Wei-Wei zhang Ying-Yang Qiu Fang Wang Department of Clinical Laboratory Anqiu People's HospitalWeifang 262123Shandong ProvinceChina Department of Gastroenterology Feicheng People's HospitalTai’an 271600Shandong ProvinceChina Yong Loo Lin school of Medicine National University of Singapore119077Singapore Department of Gastroenterology Central Hospital Affiliated to Shandong First Medical UniversityJinan 250013Shandong ProvinceChina

BACKGROUND Gastric cancer is one of the most common malignant tumors in the world,and its occurrence and development involve complex biological *** death,as a new cell death mode,has attracted wide attention in recent ***,the regulatory mechanism of iron death in gastric cancer and its effect on lipid peroxidation metabolism remain *** To explore the role of iron death in the development of gastric cancer,reveal its relationship with lipid peroxidation,and provide a new theoretical basis for revealing the molecular mechanism of the occurrence and development of gastric *** The process of iron death in gastric cancer cells was simulated by cell culture model,and the occurrence of iron death was detected by fluorescence microscopy and flow *** changes of gene expression related to iron death and lipid peroxidation metabolism were analyzed by high-throughput sequencing *** addition,a mouse model of gastric cancer was established,and the role of iron death in vivo was studied by histology and immunohistochemistry,and the level of lipid peroxidation was *** methods comprehensively and deeply reveal the regulatory mechanism of iron death on lipid peroxidation metabolism in the occurrence and development of gastric *** Iron death was significantly activated in gastric cancer cells,and at the same time,associated lipid peroxidation levels increased *** high-throughput sequencing analysis,it was found that iron death regulated the expression of several genes related to lipid *** vivo experiments demonstrated that increased iron death in gastric cancer mice was accompanied by a significant increase in lipid *** This study confirmed the important role of iron death in regulating lipid peroxidation metabolism in the occurrence and development of gastric *** activation of iron death significantly increased lipid peroxidation levels,revealing it

关键词： Ferroptosis Lipid peroxidation Gastric cancer Lipid metabolism Systematic review

Construction of multifunctional lanthanum manganese mixed nanoparticles mediated by ionic liquids for selective aerobic oxidation of cyclohexane

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Rare Metals 2024年第5期43卷 2205-2221页

作者： Hao Li Rui-Rui zhang Ke-Xin Li Shuang Wei Yu-mei Liu Rui-Xia Liu beijing Key Laboratory of Ionic Liquids Clean Process CAS Key Laboratory of Green Process and EngineeringState Key Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China university of Chinese Academy of sciences Beijing 100049China

Selective oxidation of alkanes to produce highvalue chemicals is an essential strategy and means to realize efficient utilization of *** this work,a strategy of lanthanum manganese mixed metal oxides(LMMO)regulated via a facile ionic liquid(IL)-assisted hydrothermal method was proposed to construct the multifunctional catalysts,which exhibited excellent catalytic performance in the selective aerobic oxidation of *** 8.9%cyclohexane conversion with 90%KA oi(cyclohexanol and cyclohexanone)selectivity was achieved over the optimal LMMO catalyst under mild *** effects of anion type,carbon chain length and concentration of ILs on the structure and properties of catalysts were investigated through various characterizations,indicating the structure-directing and template effect of ILs on the multifunctional *** formation of self-assembled spherical nanoparticles followed the"dissolution-nucleation-proliferation"mechanism with the introduction of 1-butyl-3.methylimidazolium hydrogen sulfate,ascribing the synergistic effect between the microenvironment of ILs and the hydrothermal ***,the high reactive oxygen concentration redox capacity,and suitable basic sites of LMMO catalysts mediated by ILs enhance the activation of C-H bonds and molecular oxygen,simultaneously influencing the adsorption and desorption of the substrate.A comprehensive understanding of the high KA oil selectivity and radical reaction mechanism was elucidated based on in situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)and radical trapping *** recycling and regeneration experiments further illuminated that the removal of adsorbed cyclohexanone acting on the LMMO catalyst was the key to achieve high KA oil selectivity.

关键词： Ionic liquids Nanoparticle Multifunctional catalyst Cyclohexane oxidation

zhang-Xuan thermal uplift and its genesis

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Progress in Natural Science:Materials International 2005年第8期15卷 725-732页

作者： SHAO Ji'an1*, NIU Shuyin2, zhang Lüqiao3.and LI Hongyang2(1. school of Earth and Space sciences, Peking {3., beijing 100871, china 2. Shijiazhuang {3. of Economics, Shijiazhuang 05003., china 3. Geological Bureau of Inner Mongolia, Huhhot 010020, china) school of Earth and Space sciences Peking University Beijing 100871 China. Shijiazhuang university of Economics Shijiazhuang 050031 China. Geological Bureau of Inner Mongolia Huhhot 010020 China

Based on the researches of the Mesozoic thermal evolution history, the deformed structures, and fission track analysis of the zhangjiakou-Xuanhua area, we obtained the following knowledge: the area experienced in 140 Ma an underplating which is marked by emplacement of mantle derived magma; during 13.—110 Ma a series of eruptions and intrusions happened, and during 80—10 Ma a rising process occurred which is synchronous with the adjacent Taihang and Yanshan Mountains and was accompanied by a series of structures down slipping from the just formed zhang-Xuan uplift toward its periphery. Combining the zhang-Xuan thermal lift with the large detachment structure in Baoding depression of the North{3. Basin in the Late Mesozoic confirms that an even larger extensional tectonic background existed in North{3. during this period.

关键词： zhang-Xuan area underplating thermal uplift fission track extensional structure.

An AIEgen nano-assembly for simultaneous detection of ATP and H_(2)S

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Chinese Chemical Letters 2024年第6期35卷 376-379页

作者： Jia-mei Qin Xue Li Wei Lang Fu-Hao zhang Qian-Yong Cao school of Chemistry and Chemical Engineering Nanchang UniversityNanchang 330031China

A new aggregation-induced emission(AIE)-based fluorescence sensor,TPEPy-SS-C14,for simultaneous recognition of adenosine triphosphate(ATP)and hydrogen sulfide(H_(2)S)has been reported via the aggregation-disaggregation *** probe self-assembles nano-structure aggregations in aqueous *** shows fluorescence turn-on response toward ATP for the complexation-enhanced aggregation,but leads to fluorescence quenching of H_(2)S for cleavage the aggregations.

关键词： AIE-based ATP detection H_(2)S detection Fluorescent sensor Cell imaging

Tetrahedral framework nucleic acids/hyaluronic acidmethacrylic anhydride hybrid hydrogel with antimicrobial and anti-inflammatory properties for infected wound healing

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International Journal of Oral Science 2024年第3期16卷 436-447页

作者： Cai Qi Qiang Sun Dexuan Xiao mei zhang Shaojingya Gao Bin Guo Yunfeng Lin State Key Laboratory of Oral Diseases&National Center for Stomatology&National Clinical Research Center for Oral Diseases&West china Hospital of Stomatology Sichuan UniversityChengduChina Sichuan Provincial Engineering Research Center of Oral Biomaterials ChengduChina Department of Stomatology The First Medical CentreChinese PLA General HospitalBeijingChina

Bacterial resistance and excessive inflammation are common issues that hinder wound *** peptides(AMPs)offer a promising and versatile antibacterial option compared to traditional antibiotics,with additional anti-inflammatory ***,the applications of AMPs are limited by their antimicrobial effects and stability against bacterial *** are regarded as a promising drug delivery platform that could enhance the antibacterial properties and stability of ***,in this study,a composite hydrogel(HAMA/t-GL13.)was prepared via the photocross-linking method,in which tFNAs carry *** hydrogel was injectable,biocompatible,and could be instantly *** exhibited broad-spectrum antibacterial and anti-inflammatory properties by inhibiting the expression of inflammatory factors and scavenging ***,the hydrogel inhibited bacterial infection,shortened the wound healing time of skin defects in infected skin full-thickness defect wound models and reduced *** constructed HAMA/tFNA-AMPs hydrogels exhibit the potential for clinical use in treating microbial infections and promoting wound healing.

关键词： properties. hydrogel anhydride

Attribution analysis of groundwater level fluctuation in the Xinxiang section of the Lower Yellow River's suspended river after the construction of the Xiaolangdi Reservoir

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Journal of Geographical sciences 2024年第7期34卷 1348-1370页

作者： LI He PING Jianhua LENG Wei mei Xuemei zhang Min LIU Jiaqi school of Water Conservancy and Transportation Zhengzhou UniversityZhengzhou450001China College of Ecology and Environment Zhengzhou UniversityZhengzhou450001China Geothermal and Ecological Geology Research Center Zhengzhou UniversityZhengzhou450001China Institute of Geology and Geophysics CASBeijing100101China

The clear identification and quantification of the factors affecting groundwater systems is crucial for protecting groundwater resources and ensuring safety in agricultural *** Lower Yellow River(LYR)is a suspended river that replenishes groundwater continuously due to clear differences in the water head,especially in the Xinxiang *** its construction,the Xiaolangdi Reservoir has reversed the LYR’s *** accurately determine the factors influencing the groundwater level(GWL),the study area was divided into five subzones based on hydrogeology.A dynamic factor model(DFM),variational mode decomposition(VMD),and a multiple linear regression model were used to identify and quantify the factors influencing the *** impact of the suspended river on the groundwater before and after the construction of the Xiaolangdi Reservoir was *** results show that:(1)The rate of decrease in the GWL was 8.53.10^(–4)m/month,and the rate of decrease in the Yellow River water level(RWL)was 4.63.10^(–4)m/month.(2)Mountain front recharge(MFR)(scale=3.months)and precipitation(scale=9 months)were the dominant factors in subzones I and II,accounting for more than 40%of the fluctuation in the *** III was dominated by exploitation(scale=7 months)and precipitation(scale=12months),accounting for 28.43.,and 23.44%of changes in the GWL,*** subzone IV,agricultural irrigation(scale=12 months)was the major factor,accounting for3..47%of GWL changes,while in subzone V,the RWL(scale=12 months)accounted for52.52%of these changes.(3.The Xiaolangdi Reservoir has increased the lateral seepage of the suspended river and altered the inter-annual *** results of this study can provide a valuable reference for controlling groundwater overexploitation and ensuring water supply security.

关键词： groundwater level influencing factor dynamic factor analysis Xiaolangdi Reservoir Lower Yellow River lateral seepage of the Yellow River

Effect of upward ion on field-aligned currents in the near-earth magnetotail

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Science china(Physics,Mechanics & Astronomy) 2007年第5期50卷 673-680页

作者： zhang LingQian1, LIU ZhenXing1, MA ZhiWei2, SHEN Chao1, ZHOU XuZhi3.& zhang XianGuo3.1 Center for Space and Applied Research, Chinese Academy of sciences, {3. 100080, china 2 Institute of Plasma Physics, Chinese Academy of sciences, Hefei 23.03., china 3.school of Earth and Space Science, Peking university, {3. 100871, china 1. Center for Space and Applied Research Chinese Academy of Sciences Beijing 100080 China 2. Institute of Plasma Physics Chinese Academy of Sciences Hefei 230031 China 3. school of Earth and Space Science Peking University Beijing 100871 China

A 3.dimensional resistive MHD simulation was carried out to study the effect of the upward ions on the field-aligned currents (FACs) in the near-earth magnetotail. The simulation results show that the up-flow ions originating from the nightside auroral oval would drift into the center plasma sheet along the magnetic field lines in the plasma sheet boundary, and have an important effect on the field-aligned currents. The main conclusions include that: 1) the upward-ions mainly affect the field- aligned currents in the near-earth magnetotail (inside 15 Re); 2) the generated FACs in the near-earth region have two types, i.e., Region 1 FAC in the high-latitude and Region 2 FAC in the low-latitude; 3. FACs increase with the enhancement of the upward ion flux; 4) with the same flux of the upward ions, FACs enhance with the increase of the velocity of the up-flow ions; 5) the intensification of FACs is also closely related with the latitude of the upward ions, and the ions from the closed field line region generate larger FACs; 6) the generation of FACs is closely related with By created by the upward ions.

关键词： up-flow ions, near-earth magnetotail, field-aligned current

Recent progress on the structure of Ser/Thr protein phosphatases

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Science china(Life sciences) 2008年第6期51卷 487-494页

作者： WANG BaiJing1,2, zhang Peng1 & WEI Qun1 1 Department of Biochemistry and Molecular Biology, beijing Normal university, beijing Key Laboratory, beijing 100875, china 2 school of Life Science, Changchun Normal university, Changchun 13.03., china 1. Department of Biochemistry and Molecular Biology Beijing Normal University Beijing Key Laboratory Beijing 100875 China 2. school of Life Science Changchun Normal University Changchun 130032 China

PP1, PP2A and PP2B, belonging to the PPP family of Ser/Thr protein phosphatases, participate in regulating many important physiological processes, such as cell cycle control, regulation of cell growth and division regulation, etc. The sequence homology between them is relatively high, and ter- tiary structure is conserved. Because of the complexity of the structure of PP2A and the diversity of its regulatory subunits, its structure is less well known than those of PP1 and PP2B. The PP2A holoen- zyme consists of a heterodimeric core enzyme, comprising a scaffolding subunit and a catalytic sub- unit, as well as a variable regulatory subunit. In this study, the subunit compositions, similarities and differences between the Ser/Thr protein phsphatases structures are summarized.

关键词： Ser/Thr phosphatases subunit composition similarities and differences crystal structure