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Coupling Coordination Analysis of Cropland Intensification and Agroecosystem Services:Evidence from Loess Plateau in shaanxi Province,China

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Chinese Geographical Science 2024年第3期34卷 401-419页

作者： FU Shaowu FU Mengyu QIU Menglong center for Land Resource research in Northwest China Shaanxi Normal UniversityXi’an 710119China

One of the greatest challenges in the agroecosystem is to improve cropland intensification while preserving agroecosystem *** many studies have investigated the effect of cropland intensification on agroecosystem service,the interactive coupling and coordination among these factors remain largely *** view of this,this study performed a case study of the Loess Plateau in shaanxi Province,China and constructed comprehensive evaluation models to quantify the cropland intensification and agroecosystem service in this *** analysis and the coupling coordination degree model were used to evaluate the interactive relationship between cropland intensification and agroecosystem service,and statistical analysis and spatial autocorrelation were used to analyze the spatial characteristics and potential mechanism of the coupling *** show that both the cropland intensification and agroecosystem service in the study area were relatively low yet gradually increased from 2000 to *** service lag was identified as the dominant unbalanced development *** the supply capacity of agroecosystem services plays a key role in the balanced development of cropland in the Loess *** coupling coordination degree between cropland intensification and agroecosystem service ranges from basic coordination to serious ***,cropland intensification practices in the area should be optimized to enhance this coordination *** upward trend was also observed in the coupling coordination degree from2000 to *** withdrawal of marginal cropland in the Grain for Green program is one of the most important reasons for this trend,especially for the northern *** 83.6%of the high-high clusters are concentrated in the southern region of the Loess Plateau,whereas 70.5%of the low-low clusters are distributed in the northern *** clustering characteristics are mainly attributed to the environmental

关键词： cropland intensification agroecosystem services balance analysis coupling coordination degree Loess Plateau,China

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Nonlinear relationship between urban form and transport CO_(2)emissions:Evidence from Chinese cities based on machine learning

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Journal of Geographical Sciences 2024年第8期34卷 1558-1588页

作者： LI Linna DENG Zilin HUANG Xiaoyan Faculty of Geographical Science Beijing Normal UniversityBeijing 100875China Northwest Land and Resources research center Global Regional and Urban Research InstituteShaanxi Normal UniversityXi'an 710119China

Reducing carbon emissions from the transport sector is essential for realizing the carbon neutrality goal in *** substantial studies on the influence of urban form on transport cO_(2)emissions,most of them have treated the effects as a linear process,and few have studied their nonlinear *** research focused on 274 Chinese cities in 2019 and applied the gradient-boosting decision tree(GBDT)model to investigate the nonlinear effects of four aspects of urban form,including compactness,complexity,scale,and fragmentation,on urban transport CO_(2)*** was found that urban form contributed 20.48%to per capita transport CO_(2)emissions(PTCEs),which is less than the contribution of socioeconomic development but more than that of transport *** contribution of urban form to total transport CO_(2)emissions(TCEs)was the lowest,at 14.3%.In particular,the effect of compactness on TCEs was negative within a threshold,while its effect on PTCEs showed an inverted U-shaped *** effect of complexity on PTCEs was positive,and its effect on TCEs was *** effect of scale on TCEs and PTCEs was positive within a threshold and negative beyond that *** effect of fragmentation on TCEs was also nonlinear,while its effect on PTCEs was positively *** results show the complex effects of the urban form on transport CO_(2)***,strategies for optimizing urban form and reducing urban transport carbon emissions are recommended for the future.

关键词： urban form transport CO,emissions nonlinear effect sustainable transport gradient-boosting decision treemodel

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Livelihood Vulnerability and Adaptation for Households Engaged in Forestry in Ecological Restoration Areas of the Chinese Loess Plateau

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Chinese Geographical Science 2024年第5期34卷 849-868页

作者： YANG Qingqing CHEN Yang LI Xiaomin YANG Jie GAO Yanhui Northwest Land and Resources research center Global Regional and Urban Research InstituteShaanxi Normal UniversityXi’an 710119China School of Geographical Science and Tourism Shaanxi Normal UniversityXi’an 710119China School of Tour-ism and research Institute of Human Geography Xi’an International Studies UniversityXi’an 710128China

Chinese Loess Plateau has achieved a win-win situation concerning ecological restoration and socio-economic ***,synergistic development may not be realized at the local *** areas undergoing ecological restoration,livelihood vulner-ability may be more pronounced due to the inflexibility,policy protection,and susceptibility to climate and market changes in forestry *** this issue has attracted academic interest,empirical studies are relatively *** study,centered on Jiaxian County,shaanxi Province of China explored the households’livelihood vulnerability and coping strategies and group heterogeneity con-cerned with livelihood structures or forestry resources through field investigation,comprehensive index assessment,and nonparametric *** showed that:1)the percentage of households with high livelihood vulnerability indicator(LVI)(>0.491)reached 46.34%.2)Eight groups in livelihood structures formed by forestry,traditional agriculture,and non-farm activities were significantly different in LVI,land resources(LR),social networks(SN),livelihood strategies(LS),housing characteristics(HC),and socio-demo-graphic profile(SDP).3)The livelihood vulnerability of the groups with highly engaged/reliance on jujube(Ziziphus jujuba)forest demonstrated more prominent livelihood vulnerability due to the increased precipitation and cold market,where the low-engaged with reliance type were significantly more vulnerable in LVI,SDP,LR,and HC.4)The threshold of behavioral triggers widely varied,and farmers dependent on forestry livelihoods showed negative coping ***,the cutting behavior was strongly associated with lagged years and government subsidies,guidance,and high returns of ***,the findings can provide guidance on the dir-ection of livelihood vulnerability mitigation and adaptive government management in ecologically restored *** issue of farmers’livelihood sustainability in the context of ecologi

关键词： livelihood vulnerability forestry coping behaviors climate change market change Jiaxian County

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Elevated nitrogen and co-evolution history with competitors shape the invasion process of Galinsoga quadriradiata

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Journal of Plant Ecology 2024年第4期17卷 9-22页

作者： Wen-Gang Zhang Xing-Jiang Song Laís Petri Gang Liu Xiao-Yan Chen Rui-Ling Liu Fang-Fang Huang Jia-Bin Zou Zhi-Hong Zhu College of Life Sciences Shaanxi Normal UniversityXi’an 710119China School for Environment and Sustainability University of MichiganAnn ArborMI 48109USA research center for UAV Remote Sensing Shaanxi Normal UniversityXi’an 710119China Changqing Teaching&research Base of Ecology Shaanxi Normal UniversityXi’an 710119China Guangdong Provincial Key Laboratory of Silviculture Protection and UtilizationGuangdong Academy of ForestryGuangzhou 510520China

Invasive plants usually experience population differentiation as they expand from their initial invasive range to the ***,invasive plants usually encounter competitors which shared different co-evolutionary histories with *** factors may lead to varying responses of invasive plant populations to elevated nitrogen deposition during ***,this issue has received limited attention in prior *** address these challenges,we conducted a greenhouse experiment to investigate how population differentiation of Galinsoga quadriradiata interacts with the presence of various competitors in response to increased nitrogen *** types(new or old that shared short or long co-evolutionary history with the invader,respectively)were set to compete with the invasive central and edge populations under different nitrogen addition *** from the central population of ***,originating from the initial invasion range,showed greater total mass,reproduction and interspecific competitiveness compared with the edge *** addition improved growth and reproductive performance in both populations,and the central population had a stronger response compared with the edge *** performance of *** was inhibited more effectively by old competitors than new *** results indicate that population differentiation occurs in terms of growth and competitiveness during the range expansion of ***,with the central population exhibiting superior ***-evolutionary history with competitors is considered unfavorable for invasive plants in this *** results highlight the combined effects of population differentiation in invasive species and their co-evolution history with competitors in the context of global change factors.

关键词： Galinsoga quadriradiata central population edge population interspecific competition population differentiation elevated nitrogen

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Response of Bacterial Community and Enzyme Activity of Greenhouse Tomato under Different Irrigation Systems

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Phyton-International Journal of Experimental Botany 2024年第7期93卷 1543-1568页

作者： Haijian Yang Mingzhi Zhang Na Xiao Yuan Li Faculty of Engineering Huanghe Science and Technology UniversityZhengzhou450063China Northwest Land and Resources research center Shaanxi Normal UniversityXi’an710119China

The micro-sprinkler irrigation mulched(MSM)has been suggested as a novel water-saving approach in con-trolled environment ***,the effects of microbial community structure and enzyme activity in the rhizosphere soil on crop growth under MSM remain *** study conducted a randomized experimen-tal design using greenhouse tomatoes to investigate changes in bacterial community structure and enzyme activity in rhizosphere soil under different irrigation frequencies(F)and amounts(I)of ***ﬁndings revealed that with the increase of F or I,The total count of soil bacteria in tomatoesﬁrst rose and then fell in terms of Opera-tional Taxonomic Units(OTUs)classiﬁ*** to other F,the most abundance of nitrogen and phos-phorus metabolism genes and enzyme activities were observed with a 5-day ***,the diversity of soil bacterial community structure initially rose before eventually declining with the increase of the *** 1.00 Epan(cumulative evaporation of a 20 cm standard pan)under MSM helped boost the abundance of nitrogen and phosphorus metabolism functional genes in soil bacteria,ensuring higher enzyme activities related to nitro-gen,carbon,and phosphorus metabolism in the rhizosphere soil of ***’yield initially rose before eventually declining with the increase in F or I,whereas I had a more signiﬁcant effect on yield.A 1.00%increase in I yielded a minimum of 39.24%increase in tomato *** study showed a positive correlation between soil bacterial community,soil enzyme activity,and greenhouse tomato yield under *** the results comprehensively,the combined irrigation mode of F of 5 d and I of 1.00 Epan was recommended for greenhouse tomatoes under *** conclusion provides theoretical support for water-saving practices and yield improve-ment in facility agriculture,especially tomato cultivation.

关键词： Greenhouse tomato yield bacterial community enzyme activity model

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Rainbow Pancyclicity in a Collection of Graphs Under the Dirac-type Condition

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 269-274页

作者： Lu-yi LI Ping LI Xue-liang LI center for Combinatorics and LPMC Nankai UniversityTianjin 300071China School of Mathematics and Statistics Shaanxi Normal UniversityXi’an 710062China

Let G={Gi:i∈[n]} be a collection of not necessarily distinct n-vertex graphs with the same vertex set V,where G can be seen as an edge-colored(multi)graph and each Gi is the set of edges with color i.A graph F on V is called rainbow if any two edges of F come from different Gis’.We say that G is rainbow pancyclic if there is a rainbow cycle Cℓof lengthℓin G for each integerℓ2[3,n].In 2020,Joos and Kim proved a rainbow version of Dirac’s theorem:Ifδ(Gi)≥2/n for each i∈[n],then there is a rainbow Hamiltonian cycle in *** this paper,under the same condition,we show that G is rainbow pancyclic except that n is even and G consists of n copies of Kn/2,n/*** result supports the famous meta-conjecture posed by Bondy.

关键词： rainbow Hamiltonian cycle rainbow pancyclic meta-conjecture

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Signifying quantum uncertainty relations by optimal observable sets and the tightest uncertainty constants

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Science China(Physics,Mechanics & Astronomy) 2024年第9期67卷 43-50页

作者： Xiao-Bin Liang Bo Li Shao-Ming Fei School of Mathematics and Computer Science Shangrao Normal UniversityShangrao 334001China Quantum Information research center Shangrao Normal UniversityShangrao 334001China School of Mathematical Sciences Capital Normal UniversityBeijing 100048China

Quantum uncertainty relations constrain the precision of measurements across multiple non-commuting quantum mechanical ***,we introduce the concept of optimal observable sets and define the tightest uncertainty constants to accurately describe these measurement *** any quantum state,we establish optimal sets of three observables for both product and summation forms of uncertainty relations,and analytically derive the corresponding tightest uncertainty *** demonstrate that the optimality of these sets remains consistent regardless of the uncertainty relation ***,the existence of the tightest constants excludes the validity of standard real quantum mechanics,underscoring the essential role of complex numbers in this ***,our findings resolve the conjecture posed in[***.118,180402(2017)],offering novel insights and potential applications in understanding preparation uncertainties.

关键词： uncertainty relation the tightest uncertainty constants optimal observable sets

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Meta-path reasoning of knowledge graph for commonsense question answering

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Frontiers of Computer Science 2024年第1期18卷 49-59页

作者： Miao ZHANG Tingting HE Ming DONG National Engineering research center for E-Learning Central China Normal UniversityWuhan 430079China Hubei Provincial Key Laboratory of Artificial Intelligence and Smart Learning Central China Normal UniversityWuhan 430079China National Language Resources Monitoring&research center for Network Media Central China Normal UniversityWuhan 430079China School of Computer Central China Normal UniversityWuhan 430079China

Commonsense question answering(CQA)requires understanding and reasoning over QA context and related commonsense knowledge,such as a structured Knowledge Graph(KG).Existing studies combine language models and graph neural networks to model ***,traditional knowledge graph are mostly concept-based,ignoring direct path evidence necessary for accurate *** this paper,we propose MRGNN(Meta-path Reasoning Graph Neural Network),a novel model that comprehensively captures sequential semantic information from concepts and *** MRGNN,meta-paths are introduced as direct inference evidence and an original graph neural network is adopted to aggregate features from both concepts and paths *** conduct sufficient experiments on the CommonsenceQA and OpenBookQA datasets,showing the effectiveness of ***,we conduct further ablation experiments and explain the reasoning behavior through the case study.

关键词： question answering knowledge graph graph neural network meta-path reasoning

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Surfactant-metal-organic framework complexes and their derivatives: advances in electrocatalysis

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Science China Chemistry 2024年第10期67卷 3209-3222页

作者： Yining Liu Mengying Wang Zuozhong Liang Haoquan Zheng Key Laboratory of Applied Surface and Colloid Chemistry Ministry of EducationSchool of Chemistry and Chemical EngineeringShaanxi Normal University

Metal-organic frameworks(MOFs) and their derivatives received more and more attention due to the diverse morphologies, rich porous structures, and tunable metal active sites, which have been widely used in energy-related electrocatalytic ***, a class of compounds with hydrophilic and hydrophobic portions in the molecular structure, are able to modulate the properties of liquid and solid surfaces. Surfactants play a crucial role in controlling the shape and size of MOFs, which helps optimize electrocatalytic performance, especially in improving the exposure and accessibility of catalytic active sites. In this review, we first outline the types and applications of surfactants. Second, we describe the interface modulation and reaction mechanism of different surfactants during the forming of MOFs and their derivatives. Finally, we discuss the current applications of surfactant-modified MOFs and their derivatives in electrocatalysis. This review provides a better understanding of surfactantassistant structure regulation and electrocatalytic activity study of MOFs and their derivatives.

关键词： metal-organic frameworks surfactants interface modulation electrocatalysis

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Blockchain Meets Generative Behavior Steganography:A Novel Covert Communication Framework for Secure IoT Edge Computing

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Chinese Journal of Electronics 2024年第4期33卷 886-898页

作者： Yuanlong CAO Junjie LI Kailin CHAO Jianmao XIAO Gang LEI School of Computer Information Engineering Jiangxi Normal University Jiangxi Blockchain Data Security and Governance Engineering research center Jiangxi Normal University School of Software Jiangxi Normal University

The rapid development of Internet of things(Io T) and edge computing technologies has brought forth numerous possibilities for the intelligent and digital future. The frequent communication and interaction between devices inevitably generate a large amount of sensitive information. Deploying a blockchain network to store sensitive data is crucial for ensuring privacy and security. The openness and synchronicity of blockchain networks give rise to challenges such as transaction privacy and storage capacity issues, significantly impeding their development in the context of edge computing and Io T. This paper proposes a reliable fog computing service solution based on a blockchain fog architecture. This paper stores data files in the inter planetary file system(IPFS) and encrypts the file hash values used for retrieving data files with stream cipher encryption. It employs a steganographic transmission technique leveraging Alpha Zero's Gomoku algorithm to discretely transmit the stream cipher key across the blockchain network without a carrier, thus achieving dual encryption. This approach aims to mitigate the storage burden on the blockchain network while ensuring the security of transaction data. Experimental results demonstrate that the model enhances the transmission capacity of confidential information from kilobytes(KB) to megabytes(MB) and exhibits high levels of covert and security features.

关键词： Steganography Ciphers Privacy Data privacy Blockchains Encryption Internet of Things

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