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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

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Detection of Serine Octamer by Desorption Electrospray Ionization Mass Spectrometry in Resultant Mixture of Aspartic Acid Exposed to Sunshine Under Natural Conditions

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Chemical Research in Chinese Universities 2007年第6期23卷 650-653页

作者： CHEN Huan-wen LI Ming jin Wei jin qin-han ZHENG Jian College of Chemistry Jilin Province Research Center of Engineering and Technology for Spectral Instruments Jilin University Changchun 130021 P. R. China Applied Chemistry Department East China University of Technology Fuzhou 344000 P. R. China College of Information Science and Engineering Zhejiang University Hangzhou 310027 P. R. China Beijing Physical and Chemical Analysis Center Beijing 100089 P. R. China

Serine, one of the nonessential amino acids, is of principal interest because of its capability to form magic-number ionic clusters, which provide a remarkable preference for homochirality. With L-aspartic acid as the precursor, this study provides experimental evidence for serine formation in weak acidified aqueous solutions in the presence of iron, with exposure to sunlight, which simulates the natural conditions of the prebiotic aqueous environment. The resultant mixture is directly analyzed via desorption electrospray ionization mass spectrometry（ DESI-MS）, without any sample preseparation. The serine monomer is successfully detected as protonated molecules, giving a peak at m/z 106, which is confirmed by the MS/MS fragments. Protonated serine octamer（ m/z 841 ） is also observed with significant abundance in the MS spectra and is confirmed by the MS/MS data, which shows the formation of the serine octamer by a synthesized serine in the resultant mixture. It is also found that the serine octamer yielded equivalent abundance in the DESI mass spectra in a wide pH range（pH = 1-5 ）, and that existence of ferrous salt and sunshine are essential for the conversion of aspartic acid to serine in the acidic water solution.

关键词： Serine octamer Aspartic acid Photocatalysis DESI Mass spectrometry

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A Hierarchical Game Model for Computation Sharing in Smart Buildings

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China Communications 2020年第3期17卷 188-204页

作者： Qianqian Wang qin Wang Shi jin Hongbo Zhu Xianbin Wang Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and TelecommunicationsNanjing 210003China School of Software Engineering Jinling Institute of TechnologyNanjing 211169China Department of Electrical and Computer Engineering Western UniversityLondonON N6A5B9Canada School of Engineering and Computing Sciences New York Institute of TechnologyNew YorkNY 10023USA National Mobile Communications Research Laboratory Southeast UniversityNanjing 210096China

Recently,initiatives to integrate Internet of Things(IoT)technologies into smart buildings have attracted extensive attention for improving the performance of buildings and the comfort of ***,the amount of data generated by IoT devices remains a challenge to the building management systems(BMSs)in terms of intensity and *** from cloud computing and edge computing,we propose a computation sharing architecture in smart buildings to incentivize idle computing devices(ICDs,sellers)to offload computational tasks for the BMS(buyer).In this paper,we design a hierarchical game model,consisting of a Stackelberg game and a Cournot game,to achieve a dynamic increase in computational capacity for the *** guarantee the utility of BMS and ICDs,the Stackelberg game model is built to analyze the interactions between BMS and ***,the Cournot game model is presented to formulate the internal competition among multiple *** the premise of the subgame perfect Nash equilibrium,the BMS can quote the optimal pricing strategy,and the ICDs can share the corresponding optimal amount of computing ***,the simulation results show that the BMS’s computational capacity is enhanced on-demand,and each participant in the game obtains maximal utility.

关键词： computation sharing Stackelberg game Cournot game incomplete information

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A Naive Particle Swarm Algorithm for Constrained Optimization Problems

A Naive Particle Swarm Algorithm for Constrained Optimizatio...

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第25届中国控制与决策会议

作者： jin qin Benliang Xie College of Computer Science & Information Guizhou University College of Science Guizhou University

ISBN: (纸本)9781467355322

In this paper, a naive particle swarm algorithm for constrained optimization problems is proposed. Also, a direct constraint handling method is adopted, which is more direct and easier to be implemented in comparison with other constraint handling methods, such as penalty function, etc. The experimental results on benchmark problems show that the proposed algorithm can solve constrained optimization problems effectively and has a robust performance.

关键词： Particle Swarm Optimization Constrained Optimization Problem Constraint Handling Penalty Function

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A causal variant rs3769823 in 2q33.1 involved in apoptosis pathway leading to a decreased risk of non-small cell lung cancer

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Cancer Biology & Medicine 2022年第9期19卷 1385-1396页

作者： Xu Zhang Na qin jingyi Fan Chang Zhang Qi Sun Yayun Gu Meng Zhu Erbao Zhang Juncheng dai Guangfu jin Hongxia Ma Zhibin Hu Hongbing Shen Department of Epidemiology Center for Global HealthSchool of Public HealthNanjing Medical UniversityNanjing 211166China Jiangsu Key Lab of Cancer Biomarkers Prevention and TreatmentCollaborative Innovation Center for Cancer Personalized MedicineNanjing Medical UniversityNanjing 211166China Health Management Center The Affiliated Suzhou Hospital of Nanjing Medical UniversitySuzhou Municipal HospitalGusu SchoolNanjing Medical UniversitySuzhou 215008China Research Units of Cohort Study on Cardiovascular Diseases and Cancers Chinese Academy of Medical SciencesBeijing 100730China

Objective:Although our previous genome-wide association study(GWAS)has identified chromosome 2q33.1 as a susceptibility locus for non-small cell lung cancer(NSCLC),the causal variants remain *** aims of this study were to identify the causal variants in 2q33.1 and to explore their biological functions in ***:CCK-8,colony formation,EdU incorporation,Transwell,and quantitative real-time polymerase chain reaction assays were applied to examine variant *** tumor xenograft model was used to examine variant function in ***-8 activity assays,flow cytometry analysis,and co-immunoprecipitation assays were used to explore the molecular ***:The missense variant rs3769823(A>G),which caused the substitution of lysine with arginine at amino acid 14 in caspase-8(caspase-8K14R),was identified as a potential causal candidate in *** with the wild type caspase-8(caspase8WT)group,the caspase-8K14R group had higher expression of caspase-8 and cleaved ***-8K14R inhibited the proliferation and metastasis of human lung cancer cell lines in ***,caspase-8K14R repressed lung cancer cell growth in ***,caspase-8K14R was more sensitive than caspase-8WT to tumor necrosis factor-related apoptosis-inducing ligand(TRAIL)-mediated apoptosis and showed higher binding of caspase-8 and ***:These results suggested that rs3769823 is the causal variant in chromosome 2q33.1 and is involved in an apoptosis pathway,leading to a decreased risk of NSCLC.

关键词： Non-small cell lung cancer chromosome 2q33.1 risk caspase-8 apoptosis

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Geometrically Shaped 32QAM and Modified Binary Switching Coding Method in Underwater Visible Light Communication

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Chinese Journal of Electronics 2022年第6期31卷 1106-1111页

作者： SHI Jianyang CAI Jifan qin Guojin jin Ruizhe LIN Xianhao CHI Nan Key Laboratory for Information Science of Electromagnetic Waves (MoE) Fudan University Peng Cheng Laboratory Shanghai Engineering Research Center of Low-Earth-Orbit Satellite Communication and Applications Shanghai Collaborative Innovation Center of Low-Earth-Orbit Satellite Communication Technology

Visible light communication(VLC) has emerged as a promising communication method in 6G,particularly in the domain of underwater ***, because of its intimate coupling to the lightemitting diodes(LED), the transmission rate is limited by the modulation bandwidth and the nonlinearity of the LED. With current device development, LED bandwidth is substantially lower than that of other optical communication devices, necessitating improved spectral efficiency and nonlinearity robustness to achieve high-speed transmission. In this paper, we propose a hexagonal constellation-based geometrically shaped(GS) 32QAM with carrierless amplitude and phase(CAP) modulation for the underwater VLC system. A comprehensive performance comparison of four GS modulation methods, including our proposed hexagonal-32QAM, normal 32QAM, square-32QAM and 32APSK is investigated in both theory and experiment. The hexagonal-32QAM with a modified binary switching coding(BSC) can obtain a Q factor gain of 0.44 dB, and a data rate improvement of 25 Mb/s compared with Gary coding based normal 32QAM. The experimentally results illustrate the feasibility of geometric shaping 32QAM in underwater visible light communication.

关键词： underwater VLC system comprehensive performance comparison modulation bandwidth amplitude shift keying carrierless amplitude and phase modulation light emitting diodes improved spectral efficiency Q factor gain communication method LED nonlinearity square-32QAM underwater visible light communication data rate improvement binary codes high-speed transmission light-emitting diodes hexagonal constellation-based geometrically shaped 32QAM quadrature amplitude modulation Gary coding based normal 32QAM free-space optical communication optical communication devices underwater optical wireless communication device development LED bandwidth optical modulation underwater communication geometric shaping 32QAM nonlinearity robustness GS modulation methods modified binary switching coding method BSC CAP phase modulation phase shift keying 32APSK hexagonal-32QAM

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Hot Deformation Behavior and Microstructures Evolution of GNP-Reinforced Fine-Grained Mg Composites

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 407-424页

作者： Hengrui Hu Jiayu qin Yunpeng Zhu jinhui Wang Xiaoqiang Li Peipeng jin qinghai Provincial Key Laboratory of New Light Alloys Qinghai UniversityXining 810016China qinghai Provincial Engineering Research Center of High Performance Light Metal Alloys and Forming Qinghai UniversityXining 810016China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China School of Material Science and Engineering Lanzhou University of TechnologyLanzhou 730050China

Graphene nanoplates(GNPs)-reinforced magnesium matrix composites have been attracted great ***,knowledge is lack for the hot deformation behavior of GNP-reinforced magnesium(GNPs/Mg)*** this study,the fine-grained GNPs/Mg composite was fabricated by powder metallurgy process followed by *** hot deformation behavior,microstructure evolution and dynamic recrystallization(DRX)mechanism of fine-grained GNPs/Mg composite were investigated by hot compression test and electron back-scatter diffraction(EBSD).The hot compression tests of the composite were conducted at temperatures between 423 and 573 K with the strain rates from 0.001 to 1 s^(-1).The strain compensated power law equation was established to describe the hot deformation behavior of the *** stress exponent and activation energy of the composite are 7.76 and 83.23 kJ/mol,respectively,suggesting that the deformation mechanism is grain boundary slip controlled dislocation climb *** abnormally high stress exponent and activation energy are unattainable in the composite due to the fine grain size of the composites and the absence of Zener pinning and Orowan effects of GNPs *** grain size increases with the decrease in Zener-Hollomn(Z)parameter,which can be well fitted by power-law *** the increase in grain size and decrease in Z parameter,the geometrically necessary dislocation density decreases,which shows the approximately power-law relationship.A random and weak texture was formed after hot *** discontinuous dynamic recrystallization and continuous dynamic recrystallization mechanism dominated the DRX behavior at 473 K/0.001 s^(-1) and 573 K/0.001 s^(-1),respectively.

关键词： GNPs Mg composite Hot deformation behavior Constitutive equations Microstructure evolution Dynamic recrystallization

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Nonscalability of Fractal Dimension to Quantify Canopy Structural Complexity from Individual Trees to Forest Stands

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Journal of Remote Sensing 2022年第1期2022卷 21-32页

作者： Xiaoqiang Liu qin Ma Xiaoyong Wu Tianyu Hu Guanhua dai jin Wu Shengli Tao Shaopeng Wang Lingli Liu qinghua Guo Yanjun Su State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China China National Botanical Garden Beijing 100093China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110164China School of Biological Sciences The University of Hong KongPokfulamHong KongChina State Key Laboratory of Agrobiotechnology Chinese University of Hong KongHong KongChina Institute of Ecology College of Urban and Environmental SciencePeking UniversityBeijing 100871China Institute of Remote Sensing and Geographical Information Systems School of Earth and Space SciencesPeking UniversityBeijing 100871China

Canopy structural complexity is a critical emergent forest attribute,and light detection and ranging(lidar)-based fractal dimension has been recognized as its powerful measure at the individual tree ***,the current lidar-based estimation method is highly sensitive to data characteristics,and its scalability from individual trees to forest stands remains *** study proposed an improved method to estimate fractal dimension from lidar data by considering Shannon entropy,and evaluated its scalability from individual trees to forest stands through mathematical ***,a total of 280 forest stand scenes simulated from the terrestrial lidar data of 115 trees spanning large variability in canopy structural complexity were used to evaluate the robustness of the proposed method and the scalability of fractal *** results show that the proposed method can significantly improve the robustness of lidar-derived fractal *** mathematical derivations and experimental analyses demonstrate that the fractal dimension of a forest stand is equal to that of the tree with the largest fractal dimension in it,manifesting its nonscalability from individual trees to forest *** nonscalability of fractal dimension reveals its limited capability in canopy structural complexity quantification and indicates that the power-law scaling theory of a forest stand underlying fractal geometry is determined by its dominant tree instead of the entire ***,we believe that fractal dimension is still a useful indicator of canopy structural complexity at the individual tree level and might be used along with other stand-level indexes to reflect the“tree-to-stand”correlation of canopy structural complexity.

关键词： fractal dimension lidar

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Interface behavior of chalcopyrite during flotation from cyanide tailings

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International Journal of Minerals,Metallurgy and Materials 2022年第3期29卷 439-445页

作者： Xuemin Qiu Hongying Yang Guobao Chen Linlin Tong Zhenan jin qin Zhang Key Laboratory for Ecological Utilization of Multi-metallic Mineral Northeastern UniversityShenyang 110819China School of Metallurgy Northeastern UniversityShenyang 110819China

The interface characteristics of cyanide tailings are different from those of the raw ore. In this study, valuable elements could not be thoroughly recovered via the flotation of cyanide tailings from Shandong, China. The interface and floatability of these tailings were investig- ated by phase analysis and flotation tests. The chalcopyrite in the cyanide tailings was fine and had a porous surface. The floatability of 68% chalcopyrite was similar to that of galena in the presence of a collector. A layer of fine galena particles compactly wrapped the chalcopyrite. The chalcopyrite recovery sharply decreased as the nonpolar oil residue in cyanide tailings was extracted using alcohol;however, this removal had no effect on the galena. The remaining chalcopyrite in the flotation tailings was covered with an oxidation layer consisting of O, Fe, S, Pb, Cu, Zn, and Si.

关键词： cyanide tailings interface behavior chalcopyrite flotation surface wrapped layer

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PREPARATION OF POLYELECTROLYTE MULTILAYER COATED MICROBUBBLES FOR USE AS ULTRASOUND CONTRAST AGENT

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Chinese Medical Sciences Journal 2008年第2期23卷 103-107页

作者： Zhan-wen Xing Heng-te Ke Shao-qin Liu Zhi-fei dai jin-rui Wang Ji-bin Liu Nanomedicine and Biosensor Laboratory Bio-X Center Harbin Institute of Technology Harbin 150080 Department of Ultrasonography Third Hospital Peking University Beijing 100083 Ultrasound Research and Education Institute Thomas Jefferson University Hospital Philadelphia 19107 USA

Objeelive To prepare and characterize polyelectrolyte multilayer film coated microbubbles for use as ultrasound contrast agent （UCA） and evaluate its effects in ultrasonic imaging on normal rabbit＇s fiver parenchyma. Methods Perfluorocarbon （PFC）-containing microbubbles （ST68-PFC） were prepared by sonication based on suffactant （ Span 60 and Tween 80）. Subsequently, the resulting ST68-PFC microbubbles were coated using oppositely charged polyelectrolytes by microbubble-templated layer-by-layer self-assembly technique via electrostatic interaction. The enhancement effects in ultrasonic imaging on normal rabbit＇s liver parenchyma were assessed. Results The obtained microbubbles exhibited a narrow size distribution. The polyelectrolytes were successfully assembled onto the surface of ST68-PFC microbubbles. In vivo experiment showed that polyelectrolyte multilayer film coated UCA effectively enhanced the imaging of rabbit＇s liver parenchyma. Conclusions The novel microbubbles UCA coated with polyelectrolyte multilayer, when enabled more function, has no obvious difference in enhancement effects compared with the pre-modified microbubbles. The polymers with chemically active groups （ such as amino group and carboxyl group） can be used as the outermost layer for attachment of targeting ligands onto microbubbles, allowing selective targeting of the microbubbles to combine with desired sites.

关键词： microbubbles ultrasound contrast agent layer-by-layer self-assembly technique polyelectrolyte

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