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Spatial heterogeneity of the driving forces of cropland change in china

Science china Earth sciences 2005年第12期48卷 2231-2240页

作者： liu xuhua1,2, wang jinfeng1, liu mingliang4.1 & meng bin1,2,3.1. Institute of Geographic {3. and Natural Resources Research, Chinese academy of {3., beijing 100101, china 2. Graduate School of the Chinese academy of {3., beijing 10003., china 3. College of Arts and {3. of beijing Union University, beijing 100083. china 4. School of Forestry and Wildlife {3., Auburn University, Auburn, Alabama, AL3.84., USA 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. School of Forestry and Wildlife sciences Auburn University Auburn AL36849 Alabama USA 4. College of Arts and sciences of beijing Union University 100083 Beijing China

By using digital satellite remote sensing data acquired in 1987―1989 and 1999―2000 and GIS combined with the natural and socio-economic data, this paper drew an integrated zonation of the cropland change and its driving forces in china. The results indicated that the cropland change in the study period was constrained by geographical factors and driven by cli-mate change as well as socio-economic system. Moreover, the regional differences of the drivers for cropland change were significant. In the midwest of china, natural condition changes and geographical background were the main constraints and drivers, while in Eastern china, social and economic changes and economic policies were the main driving forces. The cropland loss was nationwide. The dominant factors to cause this decrease included buildup of developing area to attract foreign capital and technologies, changes of industry structure due to urban in-fluence, the change of employment notions thanks to living standard improvement, rapid ur-banization due to the expansion of cities and towns, the diminished farming net income partly because of the global warming effects, and the rapid economic growth stimulated by the con-venient transportation system. These factors interact and interdepend with each other to cause the cropland loss in china recently. The reasons for the increase of cropland were primarily the cultivation and deforestation by the farmers who want to increase income. This study on the mechnism of LUCC relied on the cropland change integrated classification considering the natural or human factors both inside and outside the region, which provides a new approach to study the integrated regionalization and LUCC mechanism.

关键词： land use change, driving force, integrated classification, spatial statistics, cropland, china.

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Multifunction-oriented high-mobility polymer semiconductors

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National Science Review 2024年第3期11卷 16-19页

作者： mingliang Zhu Yunlong Guo Yunqi liu beijing National Laboratory for Molecular sciences Organic Solids Laboratory Institute of Chemistry Chinese Academy of Sciences School of Chemical sciences University of Chinese Academy of Sciences

The discovery of conductive polyacetylene has initiated interdisciplinary research into condensed matter physics and synthetic chemistry in organic electronics. Unlike their inorganic and small-molecule counterparts, polymer semiconductors possess the inherent advantages of facile solution processing,large-area manufacturing, excellent mechanical strength and intrinsic flexibility.

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Chaotic CS Encryption:An Efficient Image Encryption Algorithm Based on Chebyshev Chaotic System and Compressive Sensing

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Computers, Materials & Continua 2024年第5期79卷 2625-2646页

作者： mingliang Sun Jie Yuan Xiaoyong Li Dongxiao liu Key Laboratory of Trustworthy Distributed Computing and Service(BUPT) Ministry of EducationBeijing University of Posts and TelecommunicationsBeijing100876China

Images are the most important carrier of human information. Moreover, how to safely transmit digital imagesthrough public channels has become an urgent problem. In this paper, we propose a novel image encryptionalgorithm, called chaotic compressive sensing (CS) encryption (CCSE), which can not only improve the efficiencyof image transmission but also introduce the high security of the chaotic system. Specifically, the proposed CCSEcan fully leverage the advantages of the Chebyshev chaotic system and CS, enabling it to withstand various attacks,such as differential attacks, and exhibit robustness. First, we use a sparse trans-form to sparse the plaintext imageand then use theArnold transformto perturb the image pixels. After that,we elaborate aChebyshev Toeplitz chaoticsensing matrix for CCSE. By using this Toeplitz matrix, the perturbed image is compressed and sampled to reducethe transmission bandwidth and the amount of data. Finally, a bilateral diffusion operator and a chaotic encryptionoperator are used to perturb and expand the image pixels to change the pixel position and value of the compressedimage, and ultimately obtain an encrypted image. Experimental results show that our method can be resistant tovarious attacks, such as the statistical attack and noise attack, and can outperform its current competitors.

关键词： Image encryption chaotic system compressive sensing arnold transform

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Identification of transient receptor potential channel genes and functional characterization of TRPA1 in Spodoptera frugiperda

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Journal of Integrative Agriculture 2024年第6期23卷 1994-2005页

作者： Yutong Zhang Hangwei liu Song Cao bin Li Yang liu Guirong {3. State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100193China Shenzhen Branch Guangdong Laboratory of Lingnan Modern AgricultureGenome Analysis Laboratory of the Ministry of Agriculture and Rural AffairsAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhen 518120China Institute of Evolution and Ecology School of Life SciencesCentral China Normal UniversityWuhan 430079China

Spodoptera frugiperda is a highly destructive pest that has become a global problem due to its robust reproductive and migratory *** receptor potential(TRP)channels,which constitute a vast ion channel family,play pivotal roles in sensing the external environment and maintaining internal homeostasis in *** channels have been widely investigated for their critical roles in regulating various insect behaviors in recent *** this study,we identified 15 TRP gene loci encoding 26 transcripts in the genome of *** and analyzed their expression profiles at different developmental *** results revealed that *** possesses four TRPC genes,six TRPA genes,one TRPM gene,two TRPV genes,one TRPN gene,and one TRPML gene,while a canonical TRPP is ***,the SfruTRPA1 was functionally characterized using the Xenopus oocyte expression *** results showed that SfruTRPA1 is activated by temperature increases from 20 to 4.℃,and there is no significant desensitization after repeated stimuli within the same temperature ***,SfruTRPA1 is activated by certain natural chemicals,including allyl isothiocyanate(AITC)and cinnamaldehyde(CA).These findings provide valuable insights to the TRP genes in ***.

关键词： Spodoptera frugiperda transient receptor potential channel expression profile TRPA1 Xenopus oocyte

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Multi-omics analysis reveals the pivotal role of phytohormone homeostasis in regulating maize grain water content

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The Crop Journal 2024年第4期12卷 1081-1092页

作者： Yuanliang liu Manman Li Jianju liu Suining Deng Yan Zhang Yuanfeng Xia Baoshen liu {3. Xu State Key Laboratory of Plant Environmental Resilience/College of Agronomy and Biotechnology/National Maize Improvement Center/Center for Crop Functional Genomics and Molecular Breeding China Agricultural UniversityBeijing 100193China College of Agronomy/State Key Laboratory of Crop Biology Shandong Agricultural UniversityTai’an 271018ShandongChina Institute of Agricultural Biotechnology Jilin Academy of Agricultural SciencesGongzhuling 136100JilinChina Maize Research Institute Jilin Academy of Agricultural SciencesGongzhuling 136100JilinChina

Grain water content(GWC)is a key determinant for mechanical harvesting of maize(Zea mays).In our previous research,we identified a quantitative trait locus,qGWC1,associated with GWC in ***,we examined near-isogenic lines(NILs)NILL and NILH that differed at the qGWC1 *** GWC in NILL was primarily attributed to reduced grain water weight(GWW)and smaller fresh grain size,rather than the accumulation of dry *** difference in GWC between the NILs became more pronounced approximately 3. d after pollination(DAP),arising from a faster dehydration rate in *** an integrated analysis of the transcriptome,proteome,and metabolome,coupled with an examination of hormones and their derivatives,we detected a marked decrease in JA,along with an increase in cytokinin,storage forms of IAA(IAA-Glu,IAA-ASP),and IAA precursor IPA in immature NILL *** kernel development,genes associated with sucrose synthases,starch biosynthesis,and zein production in NILL,exhibited an initial up-regulation followed by a gradual down-regulation,compared to those in *** discovery highlights the crucial role of phytohormone homeostasis and genes related to kernel development in balancing GWC and dry matter accumulation in maize kernels.

关键词： Grain water content Maize kernel Phytohormone homeostasis

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Point Cloud Classification Using Content-Based Transformer via Clustering in Feature Space

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 231-239页

作者： Yahui liu bin Tian Yisheng Lv Lingxi Li Fei-Yue wang the State Key Laboratory for Management and Control of Complex Systems Institute of AutomationChinese Academy of SciencesBeijing 100190 the School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100190 IEEE the Transportation and Autonomous Systems Institute(TASI)and the Department of Electrical and Computer Engineering Purdue School of Engineering and TechnologyIndiana University-Purdue University Indianapolis(IUPUI)Indianapolis 46202 USA

Recently, there have been some attempts of Transformer in 3. point cloud classification. In order to reduce computations, most existing methods focus on local spatial attention,but ignore their content and fail to establish relationships between distant but relevant points. To overcome the limitation of local spatial attention, we propose a point content-based Transformer architecture, called PointConT for short. It exploits the locality of points in the feature space(content-based), which clusters the sampled points with similar features into the same class and computes the self-attention within each class, thus enabling an effective trade-off between capturing long-range dependencies and computational complexity. We further introduce an inception feature aggregator for point cloud classification, which uses parallel structures to aggregate high-frequency and low-frequency information in each branch separately. Extensive experiments show that our PointConT model achieves a remarkable performance on point cloud shape classification. Especially, our method exhibits 90.3. Top-1 accuracy on the hardest setting of ScanObjectN N. Source code of this paper is available at https://***/yahuiliu99/PointC onT.

关键词： Content-based Transformer deep learning feature aggregator local attention point cloud classification

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Paleoenvironmental Characteristics of Paleogene Lacustrine Source Rocks in the Western Bozhong Sag,Bohai Bay Basin,china:Evidence from Biomarkers,Major and Trace Elements

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 220-240页

作者： wang Xiang liu Guangdi SONG Zezhang SUN mingliang wang Xiaolin wang Feilong CHEN Rongtao GENG Mingyang LI Yishu State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing 102249China College of Geosciences China University of PetroleumBeijing 102249China china National Offshore Oil Co. Ltd.(CNOOC)Tianjin Branch CompanyTianjin 300459China CNOOC Research Institute Beijing 100028China

The organic matter(OM)enrichment mechanisms and depositional environment characteristics of lacustrine source rocks in the western Bozhong Sag,Bohai Bay Basin in Northeast china remain *** address these issues,based on Rock-Eval pyrolysis,kerogen macerals,H/C and O/C ratios,GC-MS,major and trace elements,the Dongying Formation Member(Mbr)3.E_(3.d_(3.),the Shahejie Formation mbrs 1 and 2(E_(2)s_(1+2)),and the Shahejie Mbr 3.E_(2)s_(3.)source rocks in the western Bozhong Sag were *** above methods were used to reveal their geochemical properties,OM origins and depositional environments,all of which indicate that E_(2)s_(1+2)and E_(2)s_(3.are excellent source rocks,and that E_(3.d_(3.is of the second good quality.E_(3.d_(3.source rocks were formed under a warm and humid climate,mainly belong to fluvial/delta facies,the E_(3.d_(3.sediments formed under weakly oxidizing and freshwater ***,the depositional environments of E_(2)s_(1+2)source rocks were arid and cold climate,representing saline or freshwater lacustrine facies,and the sediments of E_(2)s_(1+2)belong to anoxic or suboxic settings with large evaporation and *** the period of E_(2)s_(3.,the climate became warm and humid,indicating the freshwater lacustrine facies,and E_(2)s_(3.was characterized by freshwater and abundant ***,compared with other intervals,the OM origin of E_(3.d_(3.source rocks has noticeable terrestrial *** OM origin of the E_(2)s_(1+2)and E_(2)s_(3.are mainly plankton and *** subsidence and climate change have affected the changes of the depositional environment in the western Bozhong Sag,thus controlling the distribution of the source rocks,the geochemical characteristics in the three intervals of lacustrine source rocks have distinct ***,these factors are effective to evaluate the paleoenvironmental characteristics of source rocks by biomarkers,major and trace *** established models

关键词： petroleum geology source rocks depositional environments biomarkers major elements trace elements Bozhong Sag

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Spatial patterns of zooplankton abundance,biovolume,and size structure in response to environmental variables:a case study in the Yellow Sea and East china Sea

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Journal of Oceanology and Limnology 2024年第1期42卷 113-127页

作者： Song SUN Haochen XIAN Xiaoxia SUN mingliang ZHU mengtan liu Key Laboratory of Marine Ecology and Environmental sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China Jiaozhou Bay National Marine Ecosystem Research Station Institute of OceanologyChinese Academy of SciencesQingdao 266071China University of Chinese academy of sciences Beijing 100049China Laboratory for Marine Ecology and Environmental Science Laoshan LaboratoryQingdao 266237China

The Yellow Sea(YS)and East china Sea(ECS)are highly dynamic marginal seas of the northwestern Pacific *** gain an in-depth understanding of zooplankton community structure,zooplankton abundance,biovolume,and size structure in summer 2017 in the YS and ECS were assessed using ZooScan imaging *** abundance and biovolume ranged 2.94.1187.14.inds./m^(3.and 3.13.3.3..51 mm^(3./m^(3.,*** on the biovolume data of the categorized size classes of 26 identified taxonomic groups,the zooplankton community was classified into five groups,and each group was coupled with distinctive oceanographic *** the influence of the Yellow Sea Cold Water Mass,the Yellow Sea offshore group featured the lowest bottom temperature(10.84.3.4.℃)and the most abundant Calanoids(mainly in the 2–3.mm size class).In the Yellow Sea inshore group,Hydrozoans showed the largest biovolume and dominated in the 3.4.mm and>5-mm size *** East china Sea offshore group,which was affected by the Kuroshio Branch Current,featured high temperature and salinity,and the lowest bottom dissolved oxygen(2.58±0.5 mg/L).The lowest values of zooplankton abundance and biovolume in the East china Sea offshore group might be attributed to the bottom dissolved oxygen *** East china Sea inshore group,which was mainly influenced by the Zhejiang-Fujian Coastal Current and Changjiang Diluted Water,was characterized by high chlorophyll a and the largest biovolume of carnivorous Siphonophores(280.82±3.3.3. mm^(3./m^(3.).The Changjiang River estuary offshore group showed the most abundant Cyclopoids,which might be associated with the less turbid water mass in this *** temperature was considered the most important factor in shaping the size compositions of Calanoids in different groups.

关键词： zooplankton size structure ZooScan Yellow Sea East china Sea

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Insight into the selective separation of CO_(2)from biomass pyrolysis gas over metal-incorporated nitrogen-doped carbon materials:a first-principles study

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Frontiers of Chemical Science and Engineering 2024年第3期18卷 1-12页

作者： Li Zhao Xinru liu Zihao Ye bin Hu Haoyu wang Ji liu bing Zhang Qiang Lu National Engineering Research Center of New Energy Power Generation North China Electric Power UniversityBeijing102206China

The composition of biomass pyrolysis gas is complex,and the selective separation of its components is crucial for its further ***-incorporated nitrogen-doped materials exhibit enormous potential,whereas the relevant adsorption mechanism is still ***,16 metal-incorporated nitrogen-doped carbon materials were designed based on the density functional theory calculation,and the adsorption mechanism of pyrolysis gas components H2,CO,CO_(2),CH_(4.,and C2H6 was *** results indicate that metal-incorporated nitrogen-doped carbon materials generally have better adsorption effects on CO and CO_(2)than on H_(2),CH_(4.,and C_(2)H_(6).Transition metal Mo-and alkaline earth metal Mg-and Ca-incorporated nitrogen-doped carbon materials show the potential to separate CO and CO_(2).The mixed adsorption results of CO_(2)and CO further indicate that when the CO_(2)ratio is significantly higher than that of CO,the saturated adsorption of CO_(2)will precede that of ***,the three metal-incorporated nitrogen-doped carbon materials can selectively separate CO_(2),and the alkaline earth metal Mg-incorporated nitrogen-doped carbon material has the best *** study provides theoretical guidance for the design of carbon capture materials and lays the foundation for the efficient utilization of biomass pyrolysis gas.

关键词： CO_(2)capture biomass pyrolysis gas selective adsorption carbon materials first-principles

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Tuning mechanical behaviors of highly entangled hydrogels with the random distribution of mobile entanglements

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Applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 277-294页

作者： Jinlong liu Di LU bin CHEN Department of Engineering Mechanics Zhejiang UniversityHangzhou 310027China beijing System Design Institute of Electro-Mechanic Engineering Beijing 100854China Intelligent Robotic Research Center Zhejiang LaboratoryHangzhou 310027China Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province Hangzhou 311100China

Highly entangled hydrogels exhibit excellent mechanical properties,including high toughness,high stretchability,and low *** considering the evolution of randomly distributed entanglements within the polymer network upon mechanical stretches,we develop a constitutive theory to describe the large stretch behaviors of these *** the theory,we utilize a representative volume element(RVE)in the shape of a cube,within which there exists an averaged chain segment along each edge and a mobile entanglement at each *** employing an explicit method,we decouple the elasticity of the hydrogels from the sliding motion of their entanglements,and derive the stress-stretch relations for these *** present theoretical analysis is in agreement with experiment,and highlights the significant influence of the entanglement distribution within the hydrogels on their *** also implement the present developed constitutive theory into a commercial finite element software,and the subsequent simulations demonstrate that the exact distribution of entanglements strongly affects the mechanical behaviors of the structures of these ***,the present theory provides valuable insights into the deformation mechanism of highly entangled hydrogels,and can aid in the design of these hydrogels with enhanced performance.

关键词： highly entangled hydrogel constitutive theory entanglement gamma distribution

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