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

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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

Exploiting demand-side heterogeneous flexible resources in risk management of power system frequency

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Science China(Technological Sciences) 2024年第5期67卷 1612-1627页

作者： YAO Yu SONG YongHua ye ChengJin DING Yi ZHAO YuMing College of Electrical Engineering Zhejiang UniversityHangzhou310027China State Key Laboratory of Internet of Things for Smart City University of MacaoMacao SAR519000China Shenzhen Power Supply Bureau Co. Ltd.Shenzhen518051China

More demand-side flexible resources(DFRs)are participating in the frequency regulation of renewable power systems,whose heterogeneous characteristics have a significant impact on the system frequency ***,selecting suitable DFRs poses a formidable challenge for independent system operators(ISO).In this paper,a reserve allocation methodology for heterogeneous DFRs is proposed to manage the risk of power system ***,a performance curve is developed to describe the cost,capacity,and response speed of ***,a clustering method for multiple distributed DFRs is conducted to calculate the aggregated performance curves and uncertainty ***,the frequency security criterion considering DFRs’performance is constructed,whose linearity makes it can be easily coupled into the system scheduling model and ***,a risk management model for DFRs considering frequency-chance-constraint is proposed to make a trade-off between cost and frequency ***,the model is transformed into mixed integer second-order cone programming(MISOCP)and solved by the commercial *** proposed model is validated by the IEEE 30 and IEEE 118 bus systems.

关键词： demand-side heterogenous flexible resources risk management of power system frequency performance curve aggregation method mixed integer second-order cone programming

Targeting tau in Alzheimer's disease:from mechanisms to clinical therapy

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Neural Regeneration Research 2024年第7期19卷 1489-1498页

作者： Jinwang ye Huali Wan Sihua Chen Gong-Ping Liu Shenzhen Key Laboratory of Marine Biotechnology and Ecology College of Life Sciences and OceanographyShenzhen UniversityShenzhenGuangdong ProvinceChina Department of Laboratory Medicine Guangdong Provincial People’s Hospital(Guangdong Academy of Medical Sciences)Southern Medical UniversityGuangzhouGuangdong ProvinceChina Co-innovation Center of Neurodegeneration Nantong UniversityNantongJiangsu ProvinceChina Department of Pathophysiology School of Basic Medicine and the Collaborative Innovation Center for Brain ScienceKey Laboratory of Ministry of Education of China and Hubei Province for Neurological DisordersTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

Alzheimer’s disease is the most prevalent neurodegenerative disease affecting older *** features of Alzheimer’s disease include extra cellular aggregation of amyloid-βplaques and the accumulation of neurofibrillary tangles,fo rmed by tau protein,in the *** there are amyloid-β-ta rgeting therapies for the treatment of Alzheimer’s disease,these therapies are costly and exhibit potential negative side *** evidence suggests significant involvement of tau protein in Alzheimer’s disease-related *** an important microtubule-associated protein,tau plays an important role in maintaining the stability of neuronal microtubules and promoting axonal *** fact,clinical studies have shown that abnormal phosphorylation of tau protein occurs before accumulation of amyloid-βin the *** therapeutic strategies targeting tau protein have begun to emerge,and are considered possible methods to prevent and treat Alzheimer’s ***,abnormalities in post-translational modifications of the tau protein,including aberrant phosphorylation,ubiquitination,small ubiquitin-like modifier(SUMO)ylation,acetylation,and truncation,contribute to its microtubule dissociation,misfolding,and subcellular *** causes mitochondrial damage,synaptic impairments,gliosis,and neuroinflammation,eventually leading to neurodegeneration and cognitive *** review summarizes the recent findings on the underlying mechanisms of tau protein in the onset and progression of Alzheimer’s disease and discusses tau-targeted treatment of Alzheimer’s disease.

关键词： acetylation Alzheimer’s disease cognitive deficits gliosis mitochondria damage neuroinflammation phosphorylation synaptic impairments tau tau immunotherapy

A multi-enzymatic cascade reaction for the synthesis of bioactive C-oligosaccharides

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Chinese Chemical Letters 2024年第6期35卷 451-455页

作者： Kebo Xie Qian Zhang Fei ye Jungui Dai State Key Laboratory of Bioactive Substance and Function of Natural Medicines CAMS Key Laboratory of Enzyme and Biocatalysis of Natural Drugs and NHC Key Laboratory of Biosynthesis of Natural ProductsInstitute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China

C-Oligosaccharides are rare in nature and possess diverse ***,their chemical synthesis faces many *** this work,enzymatic introduction of C-linked sugar chains to target aglycones was successfully achieved by multi-enzymatic cascade reactions.A C-glycosyltransferase from Aloe barbadensis was employed to introduce the first C-linked glucose and then a cyclomaltodextrin glucanotransferase from Bacillus licheniformis was used to extend the sugar chain.A total of twenty C-oligosaccharides with 2-6 sugars were synthesized from scale-up reactions and exhibited good water solubility and sodium-dependent glucose transporter 2(SGLT2)inhibitory ***,a glucoamylase was used to control the length of the sugar chain and the C-maltosides were efficiently *** findings not only expanded the structural diversity of C-oligosaccharides,but also provided a strategy for the modification of C-glycoside drugs to improve the druggability.

关键词： C-Oligosaccharides C-Glycosyltransferase Cyclomaltodextrin glucanotransferase Glucoamylase Enzymatic synthesis SGLT2 inhibitory activity

Clinical prediction of insufficient vaults after implantable collamer lens implantation

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International Journal of Ophthalmology(English edition) 2024年第7期17卷 1300-1306页

作者： Jun Zhu Dan Cheng Xue-Ying Zhu Fen-Fen Li ye Yang Yu-Feng ye National Clinical Research Center for Ocular Diseases Eye HospitalWenzhou Medical UniversityWenzhou 325027Zhejiang ProvinceChina

AIM:To determine the factors related to preoperative ocular characters that are predictive of insufficient vault(<250μm)after implantable collamer lens(ICL V4c;STAAR Surgical)***:The participants underwent ICL surger... 详细信息

AIM:To determine the factors related to preoperative ocular characters that are predictive of insufficient vault(yes)and 36 patients(63 eyes)were in the low and normal vault groups,*** implantation procedures were uneventful with no cataract formation in the early postoperative *** sulcusto-sulcus lens rise(STSL)and iris ciliary angle(ICA)were correlated with vault at 3mo after *** 0.1 mm increase in STSL was associated with 38.9μm decrease in the postoperative 3-month vault.A rise of 1 degree in ICA is associated with a reduction of 4μm in ***:Eyes with a narrow ciliary sulcus are associated with a higher rate of low vault after ICL implantation,suggesting a need for adjustments to the ICL size in these *** the characteristics of the ciliary sulcus contributes valuable information to predict low vault after surgery.

关键词： insufficient vault implantable collamer lens ciliary body posterior chamber

Design and experimental research on the sweet potato seedling transplanting mechanism of the planetary gear train with deformed elliptical gear transmission

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International Journal of Agricultural and Biological Engineering 2024年第3期17卷 91-99页

作者： Bingliang ye Yuxuan ye Haili Zhou Gaohong Yu Xiong Zhao Bin Deng Faculty of Mechanical Engineering Zhejiang Sci-Tech UniversityHangzhou 310018China Zhejiang Province Key Laboratory of Transplanting Equipment and Technology Hangzhou 310018China Key Laboratory of Agricultural Equipment for Hilly and Mountainous Areas in Southeastern China(Co-construction by Ministry and Province) Ministry of Agriculture and Rural AffairsHangzhou 310018China

Aiming at the lack of suitable machines for sweet potato seedling transplanting in China,and according to the agronomic requirements for the horizontal insertion method of sweet potato seedling,a new sweet potato seedling transplanting mechanism of planetary gear train was proposed based on the non-uniform transmission of deformed elliptical *** working principle of the transplanting mechanism was analyzed,and the kinematics modeling and analysis of the mechanism were carried *** study established the numerical objectives of the transplanting mechanism and applied the theory of membership function to establish a mathematical model for the parameter-guided optimization design of the transplanting *** parameter-guided optimization design software was developed to obtain a set of optimal mechanism parameters that satisfied the motion trajectory of sweet potato transplanting and the posture of the transplanting *** on the optimized parameters,the structure of the transplanting mechanism was designed,and a virtual prototype of the mechanism was created,whereby a virtual motion simulation of the transplanting mechanism was conducted to verify the correctness of the kinematics model and design of the *** high-speed photographic kinematics test of the mechanism prototype and sweet potato seedling transplanting tests were conducted to test the mechanism’s kinematic characteristics and transplanting *** test results show that the test trajectory of the mechanism and test posture of the transplanting arm are almost consistent with the theoretical and simulation trajectory,meeting the agronomic requirements of the horizontal insertion method of sweet potato seedling;And when the rotary speed of the mechanism are 20 r/min and 30 r/min,the average success ratios of sweet potato seedlings transplanting are 90%and 82%,respectively,which prove the application feasibility of the mechanism in the practical machines.

关键词： sweet potato seedling transplanter transplanting mechanism deformed elliptical gear transmission kinematics analysis membership function optimization design

UAV-assisted cooperative offloading energy efficiency system for mobile edge computing

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Digital Communications and Networks 2024年第1期10卷 16-24页

作者： Xue-Yong Yu Wen-Jin Niu ye Zhu Hong-Bo Zhu Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and Telecommunications Nanjing210003China Engineering Research Centerof Health Service System Based on Ubiquitous Wireless Networks Ministry of EducationNanjng Universityof Posts and Telecommunications Nanjing210003China

Reliable communication and intensive computing power cannot be provided effectively by temporary hot spots in disaster areas and complex terrain ground *** this has greatly developed the application and integration of UAV and Mobile Edge Computing(MEC)to the Internet of Things(loT).However,problems such as multi-user and huge data flow in large areas,which contradict the reality that a single UAV is constrained by limited computing power,still *** to allowing UAV collaboration to accomplish complex tasks,cooperative task offloading between multiple UAVs must meet the interdependence of tasks and realize parallel processing,which reduces the computing power consumption and endurance pressure of *** the computing requirements of the user terminal,delay constraint of a computing task,energy constraint,and safe distance of UAV,we constructed a UAV-Assisted cooperative offloading energy efficiency system for mobile edge computing to minimize user terminal energy ***,the resulting optimization problem is originally nonconvex and thus,difficult to solve *** tackle this problem,we developed an energy efficiency optimization algorithm using Block Coordinate Descent(BCD)that decomposes the problem into three convex ***,we jointly optimized the number of local computing tasks,number of computing offloaded tasks,trajectories of UAV,and offloading matching relationship between multi-UAVs and multiuser *** results show that the proposed approach is suitable for different channel conditions and significantly saves the user terminal energy consumption compared with other benchmark schemes.

关键词： Computation offloading Internet of things(IoT) Mobile edge computing(MEC) Block coordinate descent(BCD)

Distributed Nash Equilibrium Seeking Strategies Under Quantized Communication

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 103-112页

作者： Maojiao ye Qing-Long Han Lei Ding Shengyuan Xu Guobiao Jia IEEE the School of Automation Nanjing University of Science and TechnologyNanjing 210094China the School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyMelbourne VIC 3122Australia the Institute of Advanced Technology Nanjing University of Posts and TelecommunicationsNanjing 210023China

This paper is concerned with distributed Nash equi librium seeking strategies under quantized communication. In the proposed seeking strategy, a projection operator is synthesized with a gradient search method to achieve the optimization o players' objective functions while restricting their actions within required non-empty, convex and compact domains. In addition, a leader-following consensus protocol, in which quantized informa tion flows are utilized, is employed for information sharing among players. More specifically, logarithmic quantizers and uniform quantizers are investigated under both undirected and connected communication graphs and strongly connected digraphs, respec tively. Through Lyapunov stability analysis, it is shown that play ers' actions can be steered to a neighborhood of the Nash equilib rium with logarithmic and uniform quantizers, and the quanti fied convergence error depends on the parameter of the quan tizer for both undirected and directed cases. A numerical exam ple is given to verify the theoretical results.

关键词： Consensus distributed Nash equilibrium seeking projected gradient play quantized communication

A new database of building-space-specific internal loads and load schedules for performance based code compliance modeling of commercial buildings

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Building Simulation 2024年第6期17卷 877-892页

作者： Yunyang ye Cary A.Faulkner Wooyoung Jung Jian Zhang Eli Brock Pacific Northwest National Laboratory RichlandWA99354USA University of Pittsburgh PittsburghPA15260USA

Building-level loads and load schedules prescribed by current modeling rules save modelers time and provide standards during whole building performance ***,recent studies show that they sometimes insufficiently capture the entire building performance due to the varied loads and load schedules for different space *** a solution to this issue,this paper presents a database of default building-space-specific loads and load schedules for use in energy modeling,and in particular code compliance modeling for commercial *** existing sets of default loads and load schedules are reviewed and the challenges behind using them for specific research topics are ***,the proposed method to develop the building-space-specific loads and load schedules is *** that,the database for these building-space-specific loads and load schedules is *** addition,one case is studied to demonstrate the applications of these loads and load *** this case study,three methods are used to develop building energy models:space-specific(using knowledge of the distribution and location of space types and applying the space-specific data in the developed database),building-level(assuming a lack of knowledge of the space types and using the building-level data in the developed database),and calculated-ratio(assuming knowledge of the distribution of space types but not their locations and calculating weighted average values based on the space-specific data in the developed database).The energy results simulated by using these three methods are compared,which shows building-level methods can produce significantly different absolute energy and energy savings results than the results using space-specific ***,this paper discusses the application scope and maintenance of this new database.

关键词： load load schedule space specific building energy modeling code compliance