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Spatially explicit reconstruction of cropland cover in Europe from AD 1800 to 2000

Science china Earth Sciences 2024年第9期67卷 2953-2971页

作者： jun LI Yu YE Xiuqi FANG Diyang ZHANG Zhilei wu Faculty of Geographical Science Beijing Normal UniversityBeijing 100875China Key Laboratory of Environmental Change and Natural Disaster Ministry of EducationBeijing Normal UniversityBeijing 100875China College of Geographical Science Qinghai Normal UniversityXining 810016China

One of the challenges in global change research is the significant uncertainty in global historical land use and land cover(LUCC)datasets,which are widely used as foundational *** addition to the regional cropland area reconstructions,improving the grid allocation method is another feasible way to raise the reliability of historical LUCC *** this study,an integrated reconstruction of the national cropland areas over the past 200 years was developed for 36 European *** that,the allocation algorithm was built using physiogeographic variables and historical city sites for accounting for land suitability and cultivation preferences,***,cropland data in Europe with a spatial resolution of 5′×5′at five time sections from AD 1800 to 2000 were generated using the optimal allocation algorithm in accordance with the stages of the regional *** results were as follows:(1)The dominant factors governing the distribution of croplands in Europe vary at different agricultural stages,but the results can be merged *** suitability was more optimal for allocation during the modern agricultural stage(AD 1950 and 2000);the priority index combined with land suitability and cultivation preference was more reasonable for allocation during the traditional agricultural stage(AD 1800).The average of the allocations by priority index and the land suitability could be adopted as the allocation results during the transitional stage(AD 1850 and 1900)because the grids for absolute differences within±10 and±20 percentage points between the results obtained from the above two allocations were above 80% and 95%,respectively,which means the two allocation results could be merged.(2)Over the past 200 years,the total cropland area in Europe first increased to a peak in AD 1900 and then ***,the centre of the higher cropland fraction shifted from the western part of Europe in AD 1800 to the eastern part of the continent after AD 1950.(3)

关键词： Land use and land cover change Historical cropland Gridding allocation Europe Past 200 years

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Occurrence and possible sources of antibiotic resistance genes in seawater of the South china Sea

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Frontiers of Environmental Science & Engineering 2024年第9期18卷 27-38页

作者： Jian Lu jun wu Cui Zhang Jianhua Wang Xia He CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone Research(YIC)Chinese Academy of Sciences(CAS)Shandong Key Laboratory of Coastal Environmental ProcessesYICCASYantai 264003China Yantai Research Institute Harbin Engineering UniversityYantai 264006China College of Environmental Science and Engineering Guilin University of TechnologyGuilin 541006China

Antibiotic resistance genes(ARGs)might have great effect on ecological security and human *** are important reservoirs that receive tremendous amounts of pollutants ***,information on the proliferation of ARGs in seawater is still *** study performed field sampling to investigate the occurrence and distribution of ARGs in seawater of the South china Sea,which is the deepest and largest sea in *** results showed that the total absolute abundances of ARGs in seawater samples ranged from 2.1×10^(3)to 2.3×10^(4)copies/mL,with an of 5.0×10^(3)copies/mL and a range of 2.2×10^(3)–1.8×10^(4)copies/mL for those with mobile genetic elements(MGEs).Genes resistant to multidrug,aminoglycoside,tetracycline,and fluoroquinolone antibiotics accounted for 77.3%–88.6%of total ARGs in *** and Cyanobacteria represented 32.1%–56.2%and 30.4%–49.5%of microbial community,***_MIT9313 and Clade_la were the prevalent genera in seawater of the South china *** co-occurrence relationship existed among ARGs,MGEs,and *** activities had critical influence on ARGs and *** wastewater,wastewater treatment plant effluent,sewage,aquaculture tailwater,and runoff were determined as the important sources of ARGs in seawater of the South china Sea based on positive matrix factorization analysis.

关键词： The South china Sea Antibiotic resistance genes Mobile genetic element Source apportionment

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Weakly Approximate Diagonalization of Homomorphisms into Finite von Neumann Algebras

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2187-2194页

作者： Wen Hua QIAN jun Hao SHEN Wen Ming wu School of Mathematical Sciences Chongqing Normal UniversityChongqing 401331P.R.China Department of Mathematics and Statistics University of New HampshireDurhamNH 03824USA

Let A be a unital C^(∗)-algebra and B a unital C^(∗)-algebra with a faithful traceτ.Let n be a positive *** give the definition of weakly approximate diagonalization(with respect toτ)of a unital homomorphismφ:A→Mn(B).We give an equivalent characterization of McDuff Ⅱ_(1) *** show that,if A is a unital nuclear C^(∗)-algebra and B is a type Ⅱ_(1) factor with faithful traceτ,then every unital^(∗)-homomorphism φ:A→M_(n)(B)is weakly approximately *** B is a unital simple infinite dimensional separable nuclear C^(∗)-algebra,then any finitely many elements in Mn(B)can be simultaneously weakly approximately diagonalized while the elements in the diagonals can be required to be the same.

关键词： Weakly approximately diagonalizable McDuff factors nuclear hyperfinite

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A Novel Disturbance Observer Based Fixed-Time Sliding Mode Control for Robotic Manipulators With Global Fast Convergence

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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 661-672页

作者： Dan Zhang Jiabin Hu jun Cheng Zheng-Guang wu Huaicheng Yan IEEE Zhejiang University of Technology Guangxi Normal University Zhejiang University the East china University of Science and Technology

This paper proposes a new global fixed-time sliding mode control strategy for the trajectory tracking control of uncertain robotic ***,a fixed-time disturbance observer(FTDO) is designed to deal with the adverse effects of model uncertainties and external disturbances in the manipulator *** an adaptive scheme is used and the adaptive FTDO(AFTDO) is developed,so that the priori knowledge of the lumped disturbance is not ***,a new non-singular fast terminal sliding mode(NFTSM) surface is designed by using an arctan function,which helps to overcome the singularity problem and enhance the robustness of the *** on the estimation of the lumped disturbance by the AFTDO,a fixed-time non-singular fast terminal sliding mode controller(FTNFTSMC)is developed to guarantee the trajectory tracking errors converge to zero within a fixed *** settling time is independent of the initial state of the *** addition,the stability of the AFTDO and FTNFTSMC is strictly proved by using Lyapunov ***,the fixed-time NFESM(FTNFTSM) algorithm is validated on a 2-link manipulator and comparisons with other existing sliding mode controllers(SMCs) are *** comparative results confirm that the FTNFTSMC has superior control performance.

关键词： Disturbance observer(DO) fixed-time non-singular sliding mode control robotic manipulator trajectory tracking

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The modulatory effect of oolong tea polyphenols on intestinal flora and hypothalamus gene expression in a circadian rhythm disturbance mouse model

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Food Science and Human Wellness 2024年第2期13卷 748-764页

作者： Ruonan Yan chi-Tang Ho Yanan Liu Shengnan Zhan Zufang wu Xin Zhang Department of Food Science and Engineering Ningbo UniversityNingbo 315211China Department of Food Science Rutgers UniversityNew BrunswickNew Jersey 08901USA

The interaction between host circadian rhythm and gut microbes through the gut-brain axis provides new clues for tea polyphenols to improve host *** present research showed that oolong tea polyphenols(OTP)improved the structural disorder of the intestinal flora caused by continuous darkness,thereby modulating the production of metabolites related to pyruvate metabolism,glycolysis/gluconeogenesis,and tryptophan metabolism to alleviate the steady-state *** fecal microbiota transplantation from the OTP group,the single-cell transcriptomic analysis revealed that OTP significantly increased the number of hypothalamus cell clusters,up-regulated the number of astrocytes and fibroblasts,and enhanced the expression of circadian rhythm genes Cry2,Per3,Bhlhe41,Nr1d1,Nr1d2,Dbp and Rorb in hypothalamic *** results confirmed that OTP can actively improve the intestinal environmental state as well as internal/peripheral circadian rhythm disorders and cognitive impairment,with potential prebiotic functional characteristics to notably contribute to host health.

关键词： Gut microbiota Circadian rhythm Oolong tea polyphenols Single-cell sequencing Metabolism

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Effects of arbuscular mycorrhizal fungi on zinc uptake,translocation and accumulation in winter wheat during whole plant growth stages

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Pedosphere 2024年第2期34卷 374-384页

作者： Jing YANG Chuangye ZHANG Yifan LIU Yuanzhe MA Xiangyao wu jun CAI Fuyong wu College of Natural Resources and Environment Northwest A&F UniversityYangling 712100China Key Laboratory of Plant Nutrition and Agricultural Environment of Northwest of Ministry of Agriculture Yangling 712100China

Although arbuscular mycorrhizal fungi(AMF)could play important roles in zinc(Zn)uptake in host plants,the effects of AMF on Zn uptake and transport in winter wheat during the whole growth stages remain unclear.A pot experiment was conducted to investigate the effects of Funneliformis mosseae(Fm)and Claroideoglomus etunicatum(Ce)on Zn absorption,transport,and accumulation in winter wheat growing in soils spiked with different Zn levels(0,2.5,and 25 mg kg^(-1)).The results showed that there was a significant correlation between mycorrhizal colonization rate and Zn absorption efficiency in winter wheat roots during the post-anthesis period,but there was no significant correlation during the pre-anthesis *** mycorrhizal fungi significantly increased Zn concentrations(0.56–1.58 times)in wheat grains under 0 mg kg^(-1)Zn level,but decreased Zn concentrations in wheat grains under 25 mg kg^(-1)Zn ***,at the filling and maturity stages,AMF increased Zn absorption rate and the contribution of root Zn uptake to grain Zn by 3–14 and 0.36–0.64 times,respectively,under 0 mg kg^(-1)Zn level and 0.21–1.02 and 0.27–0.37 times,respectively,under 2.5 mg kg^(-1)Zn ***,AMF decreased root Zn absorption rate(0.32–0.61 times)and increased the contribution of Zn remobilization in vegetative tissues to grain Zn(1.69–2.01 times)under 25 mg kg^(-1)Zn *** study would complement the mechanisms and effects of AMF on Zn absorption and transport in winter wheat and provide a potential method for the application of AMF to enrich wheat grain Zn.

关键词： grain Zn source mycorrhizal response post-anthesis period Zn absorption rate Zn remobilization

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Leaching kinetics and permeability of polyethyleneimine added ammonium sulfate on weathered crust elution-deposited rare earth ores

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Journal of Rare Earths 2024年第8期42卷 1610-1619,I0008页

作者： Huifang Yang Aoyang Sha Zhengyan He Chenjie wu Yuanlai Xu Jingjing Hu Zhigao Xu Ru'an chi Key Laboratory for Green Chemical Process of Ministry of Education School of Resources&Safety EngineeringWuhan Institute of TechnologyWuhan 430073China Key Laboratory of Resources Conversion and Pollution Control of the State Ethnic Affairs Commission College of Resources and Environmental ScienceSouth-Central MinzuUniversityWuhan430074China

At present,in-situ leaching of weathered crust elution-deposited rare earth ores(WCE-DREOs) encounter with problems such as long leaching cycles,slow infiltration rate and low product *** order to solve the above problems,the conventional leaching agent ammonium sulfate((NH_(4))_(2)SO_(4)) was compounded with polymeric surfactant polyethyleneimine(PEI) to form a composite leaching *** effects of leaching temperature,PEI *** rate and pH on leaching kinetics and permeability of rare earths(RE) and aluminum(AI) in orebody were *** is found that with temperature increasing,the time required to reach leaching equilibrium for both RE and Al is shortened,the apparent activation energies of RE and AI are 14.79 and 13.45 kJ/mol,respectively,and the leaching processes are in accordance with the outer diffusion control,When the concentrations of(NH_(4))_(2)SO_(4) and PEI in the composite leaching agent are 2.0 wt% and 0.4 wt%;the time required to reach leaching equilibrium for RE and AI is about 50% shorter than that using(NH_(4))_(2)SO_(4) alone,and the leaching efficiencies of RE are slightly higher than that of *** increasing the temperature and flow rate of the composite leaching agent can improve the leaching efficiencies of RE and Al,but pH has neglected effects on the leaching efficiencies of *** PEI concentrations below 0,4 wt%, the addition of PEI promotes the leaching of RE and *** column leaching studies of the WCE-DREO,the addition of 0.4 wt% PEI to the traditional leaching agent(NH_(4))_(2)SO_(4) has no impact on the leaching efficiencies of ***,it can significantly increase the infiltration rate of WCE-DREO,shortening the leaching time per 10 mL effluent from about 30 min for(NH_(4))_(2)SO_(4) leaching system to 20 min for the composite leaching *** leaching time is shortened by one-third,and the leaching cost is reduced,which can provide theoretical guidance for the development and commercial implementa

关键词： Polyethyleneimine Kinetics Rare earths Permeability Activation energy

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Unraveling the complex roles of macrophages in obese adipose tissue:an overview

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Frontiers of Medicine 2024年第2期18卷 205-236页

作者： Chang Peng jun Chen Rui wu Haowen Jiang Jia Li Hangzhou Institute for Advanced Study University of Chinese Academy of SciencesHangzhou310000China State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai201203China University of chinese Academy of Sciences Beijing100049China Department of Prosthodontics Shanghai Engineering Research Center of Advanced Dental Technology and MaterialsShanghai Key Laboratory of Stomatology&Shanghai Research Institute of StomatologyNational Clinical Research Center for Oral DiseasesShanghai Ninth People’s HospitalCollege of StomatologyShanghai Jiao Tong University School of MedicineShanghai200011China

Macrophages,a heterogeneous population of innate immune cells,exhibit remarkable plasticity and play pivotal roles in coordinating immune responses and maintaining tissue homeostasis within the context of metabolic *** activation of inflammatory macrophages in obese adipose tissue leads to detrimental effects,inducing insulin resistance through increased inflammation,impaired thermogenesis,and adipose tissue ***,adipose tissue macrophages also play a beneficial role in maintaining adipose tissue homeostasis by regulating angiogenesis,facilitating the clearance of dead adipocytes,and promoting mitochondrial *** the heterogeneity of macrophages in obese adipose tissue is crucial for unraveling the pathogenesis of obesity and holds significant potential for targeted therapeutic ***,the dual effects and some potential regulatory mechanisms of macrophages in adipose tissue have been elucidated using single-cell *** this review,we present a comprehensive overview of the intricate activation mechanisms and diverse functions of macrophages in adipose tissue during obesity,as well as explore the potential of drug delivery systems targeting macrophages,aiming to enhance the understanding of current regulatory mechanisms that may be potentially targeted for treating obesity or metabolic diseases.

关键词： obesity inflammation adipose tissue macrophages adipose tissue homeostasis

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Experimental study of the damage characteristics of rocks containing non-penetrating cracks under cyclic loading

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International Journal of Mining Science and Technology 2024年第2期34卷 197-210页

作者： jun Xu Xiaochun Xiao Lu Ma Sen Luo Jiaxu Jin Baijian wu School of Mechanics and Engineering Liaoning Technical UniversityFuxin 123000China School of Civil Engineering Liaoning Technical UniversityFuxin 123000China Department of Engineering Mechanics Southeast UniversityNanjing 211189China

The damage evolution process of non-penetrating cracks often causes some unexpected engineering *** specimens containing non-penetrating crack(s)are used to study the damage evolution and characteristics under cyclic *** results show that under cyclic loading,the relationship between the number of non-penetrating crack(s)and the characteristic parameters(cyclic number,peak stress,peak strain,failure stress,and failure strain)of the pre-cracked specimens can be represented by a decreasing linear *** damage evolution equation is fitted by calibrating the accumulative plastic strain for each cycle,and the damage constitutive equation is proposed by the concept of effective ***,non-penetrating cracks are more likely to cause uneven stress distribution,damage accumulation,and local failure of *** local failure can change the stress distribution and relieve the inhibition of non-penetrating crack extension and eventually cause a dramatic destruction of the ***,the evolution process caused by non-penetrating cracks can be regarded as one of the important reasons for inducing *** results are expected to improve the understanding of the process of spalling formation and rockburst and can be used to analyze the stability of rocks or rock structures.

关键词： Damage characteristics Constitutive model Fissured rocks Non-penetrating crack Cyclic loading

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Mesoporous molecular sieve confined phase change materials with high absorption,enhanced thermal conductivity,and cooling energy charging/discharging capacity

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Frontiers of Materials Science 2024年第1期18卷 1-14页

作者： Qi Zhang Chongyang Liu Xuehong wu Xueling Zhang jun Song School of Energy and Power Engineering Zhengzhou University of Light IndustryZhengzhou 450007China

The biggest challenge for organic phase change materials(PCMs)used in cold energy storage is to maintain high heat storage capacity while reducing the leakage risk of PCMs during the phase transition *** is crucial for expanding their applications in the more demanding cold storage *** this study,novel formstable low-temperature composite PCMs are prepared with mesoporous materials,namely SBA-15 and CMK-3(which are prepared using the template method),as supporting matrices and dodecane as the *** to the combined effects of capillary forces within mesoporous materials and interactions among dodecane molecules,both dodecane/SBA-15 and dodecane/CMK-3 exhibit outstanding shape stability and thermal cycling stability even after 200 heating/cooling *** comparison to those of dodecane/SBA-15,dodecane/CMK-3 exhibits superior cold storage performance and higher thermal ***,the phase transition temperature of dodecane/CMK-3 is-8.81℃ with a latent heat of 122.4 J·g^(-1).Additionally,it has a thermal conductivity of 1.21 W·m^(-1)·K^(-1),which is 9.45 times that of dodecane *** these highlight its significant potential for applications in the area of cold energy storage.

关键词： cold energy storage phase change material mesoporous molecular sieve CMK-3 SBA-15 cooling energy charging/discharging capacity

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