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Distribution and mapping of temperate savanna in the sandy lands of eastern China

Science China Earth Sciences 2025年第1期68卷 128-141页

作者： Xiaoya LI Feng WANG Tao DUAN Kaijie YANG Bin YANG Chunmei WANG Xin TIAN Qi lu Institute of Ecological Conservation and Restoration Institute of Desertification StudiesChinese Academy of ForestryBeijing100091China Institute of Desertification Institute of Desertification StudiesChinese Academy of ForestryBeijing100091China Institute of Great Green Wall Bayan Nur015200China Satellite Application Centre for Ecology and Environment MEEBeijing100094China Institute of Microelectronics Chinese Academy of SciencesBeijing100029China Aerospace Information Research Institute Chinese Academy of SciencesBeijing100094China Institute of Forest Resource Information Techniques Chinese Academy of ForestryBeijing100091China

Savannas are distributed globally across various *** perform a significant socioeconomic role in regulating net primary productivity and the terrestrial carbon *** to the high spatial heterogeneity induced by the mixed distribution of trees and grasses,current global land-cover classification maps often classify savannas as forests or grasslands Temperate savannas in China cover a vast area,yet their spatial patterns and extent remain poorly *** study developed a novel remote sensing temperate savannas mapping method by integrating very high-resolution(VHR)unmanned aerial vehicle(UAV)and GF-6 satellite imagery based on the vegetation structure characteristics of temperate savannas using the FAO definition of *** and validation datasets were collected from VHR UAV imagery covering the main temperate savannah types with a ground area of 1818 *** fractional woody vegetation cover(FWVC)and fractional herbaceous vegetation cover(FHVC)in temperate savannas were estimated by integrating Classification and Regression Tree and Random Forest *** current distribution of temperate savannas in the Horqin and Otindag Sandy Lands of Eastern China was mapped to a unit area of 0.5 *** root-mean-square error(RMSE)values for the FWVC and FHVC models were 10.69%and 11.67%,and the R^(2)values were 0.66 and 0.63,*** assessment indicated that the new temperate savanna map had high identification accuracy,with a Kappa coefficient of 0.70,overall accuracy of 0.88,and average accuracy of *** savannas in the sandy lands of eastern China were primarily distributed in the northern Horqin Sandy Land the central and eastern regions of the Otindag Sandy Land,and the transition zone from the southern slopes of the Greater Khingan Mountains to the plains,covering a total area of 3.27×10^(6)*** main savannah types were elm,oak/maple,and shrub *** savannas were widely distributed in the Otindag Sandy Land a

关键词： Temperate savanna UAV imagery GF-6 Fractional woody vegetation cover Fractional herbaceous vegetation cover Machine learning

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NIR driven catalytic enhanced acute lung injury therapy by using polydopamine@Co nanozyme via scavenging ROS

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Chinese Chemical Letters 2025年第2期36卷 337-343页

作者： Xiaoshuai Wu Bailei Wang Yichen Li Xiaoxuan Guan Mingjing Yin Wenquan Lv Yin Chen Fei lu Tao Qin Huyang Gao Weiqian Jin Yifu Huang Cuiping Li Ming Gao Junyu lu Intensive Care Unit The Second Affiliated Hospital of Guangxi Medical University Department of Critical Care Medicine The Ninth Affiliated Hospital of Guangxi Medical University Life Sciences Institute Guangxi Medical University Department of Emergency The First Affiliated Hospital of Guangxi Medical University College & Hospital of Stomatology Guangxi Medical University Guangxi Key Laboratory of Oral and Maxillofacial Rehabilitation and Reconstruction Guangxi Medical University

Acute lung injury(ALI) was characterized by excessive reactive oxygen species(ROS) levels and inflammatory response in the lung. Scavenging ROS could inhibit the excessive inflammatory response, further treating ALI. Herein, we designed a novel nanozyme(P@Co) comprised of polydopamine(PDA) nanoparticles(NPs) loading with ultra-small Co, combining with near infrared(NIR) irradiation, which could efficiently scavenge intracellular ROS and suppress inflammatory responses against ALI. For lipopolysaccharide(LPS) induced macrophages, P@Co + NIR presented excellent antioxidant and anti-inflammatory capacities through lowering intracellular ROS levels, decreasing the expression levels of interleukin-6(IL-6)and tumor necrosis factor-α(TNF-α) as well as inducing macrophage M2 directional polarization. Significantly, it displayed the outstanding activities of lowering acute lung inflammation, relieving diffuse alveolar damage, and up-regulating heat shock protein 70(HSP70) expression, resulting in synergistic enhanced ALI therapy effect. It offers a novel strategy for the clinical treatment of ROS related diseases.

关键词： Acute lung injury M2 directional polarization Nanozyme NIR driven ROS scavenging

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Phase-transfer-shuttle generated in situ enables novel SN1-type fluorination of sulfonium ylide with hydrofluoric acid

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Science China Chemistry 2025年第2期68卷 641-648页

作者： Yisa Xiao Rui Wang Zhaoxuan Xu Qunchao Zhao Renyi Pang Tao Dong Long lu Qilong Shen Key Laboratory of Fluorine and Nitrogen Chemistry and Advanced Materials Shanghai Institute of Organic ChemistryUniversity of Chinese Academy SciencesChinese Academy of SciencesShanghai 200032China

The development of a nucleophilic fluorination protocol using hydrofluoric acid as the fluoride source represents a long-sought goal in the field of organofluorine *** report herein the realization of such a reaction that employed alkyl-substituted sulfonium ylides as the *** key to the success of the protocol was attributed to two factors:First,as a Brϕnsted base,the ylide was able to be protonated by HFaq,thus serving as a phase-transfer shuttle generated in situ to bring F−from aqueous phase to the organic phase promoting desolvation of fluoride ***,after protonation,a sulfonium salt,a good leaving group,was generated and subsequent attacked by the fluoride to afford the alkyl *** investigation indicates that the reaction occurs via an SN1 *** of the nature of the cationic intermediate in the reaction,two attractive rearrangement-fluorination approaches including 1,2-aryl migration fluorination and ring-expansion fluorination were disclosed.

关键词： SN1 fluorination hydrofluoric acid sulfonium ylide cation rearrangement

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Long non-coding RNAs as promising targets for controlling disease vector mosquitoes

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Insect Science 2025年第1期32卷 24-41页

作者： Yujiao Han Qian Pu Ting Fan Tianqi Wei Yankun Xu lu Zhao Shiping Liu State Key Laboratory of Resource Insects Southwest UniversityChongqing400716 China

Hematophagous female mosquitoes are important vectors of numerous devastating human diseases,posing a major public health *** prevention and control of mosquito-borne diseases rely considerably on progress in understanding the molecular mechanisms of various life activities,and accordingly,the molecules that regulate the various life activities of mosquitoes are potential targets for implementing future vector control *** long non-coding RNAs(lncRNAs)have been identified in mosquitoes and significant progress has been made in determining their ***,we present a comprehensive overview of the research advances on mosquito lncRNAs,including their molecular identification,function,and interaction with other non-coding RNAs,as well as their synergistic regulatory roles in mosquito life *** also highlight the potential roles of competitive endogenous RNAs in mosquito growth and development,as well as in insecticide resistance and virus–host *** into the biological functions and mechanisms of lncRNAs in mosquito life activities,viral replication,pathogenesis,and transmission will contribute to the development of novel drugs and safe vaccines.

关键词： competitive endogenous RNAs(ceRNAs) insecticide resistance long noncoding RNA(lncRNA) mosquito mosquito-borne diseases pathogen-host interaction

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Hymenopteran-specific TRPA channel from the Texas leaf cutter ant(Atta texana)is heat and cold activated and expression correlates with environmental temperature

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Insect Science 2025年第1期32卷 301-320页

作者： Julia M.York Timothy N.Taylor Sarah LaPotin Ying lu Ulrich Mueller Department of Evolution Ecologyand BehaviorUniversity of Illinois Urbana-ChampaignUrbanaUSA Department of Integrative Biology University of Texas at AustinAustinUSA Institute for Neuroscience University of Texas at AustinAustinUSA Department of Human Genetics University of UtahSalt Lake CityUSA

Leaf cutting ants of the genus Atta cultivate fungal gardens,carefully modifying environmental conditions to maintain optimal temperature for fungal *** nerves from Atta are highly temperature sensitive,but the underlying molecular sensor is ***,we utilize Atta texana(Texas leaf cutter ant)to investigate the molecular basis of ant temperature sensation and how it might have evolved as the range expanded northeast across Texas from ancestral populations in *** focus on transient receptor potential(TRP)channel genes,the best characterized temperature sensor proteins in *** texana antennae express 6 of 13 Hymenopteran TRP channel genes and sequences are under a mix of relaxed and intensified *** a behavioral assay,we find *** workers prefer 24℃(range 21−26℃)for fungal *** was no evidence of regulatory evolution across a temperature transect in Texas,but instead Hymenoptera-specific TRPA(HsTRPA)expression highly correlated with ambient *** expressed in vitro,HsTRPA from *** is temperature activated with Q10 values exceeding 100 on initial exposure to temperatures above 33℃.Surprisingly,HsTRPA also appears to be activated by cooling,and therefore to our knowledge,the first non-TRPA1 ortholog to be described with dual heat/cold activation and the first in any invertebrate.

关键词： electrophysiology evolution invertebrate leaf cutter ants temperature TRPchannels

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水轮机主轴断裂原因分析

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大电机技术 2015年第3期 50-53页

作者：卢从义王治国高秀玲丁军锋水力发电设备国家重点实验室哈尔滨150040

本文采用金相分析、光谱分析、SEM分析和ANSYS有限元分析等手段对水轮机主轴的裂纹产生原因进行了分析。分析结果表明,水轮机主轴上安装的抗磨环止口底端恰好处在熔合线上,该位置应力集中,且存在导致材料综合性能恶化的魏氏组织,运行时... 详细信息

本文采用金相分析、光谱分析、SEM分析和ANSYS有限元分析等手段对水轮机主轴的裂纹产生原因进行了分析。分析结果表明,水轮机主轴上安装的抗磨环止口底端恰好处在熔合线上,该位置应力集中,且存在导致材料综合性能恶化的魏氏组织,运行时在交变载荷作用下萌生裂纹并不断扩展,导致疲劳开裂。

关键词： 20Si Mn 主轴水轮机疲劳裂纹

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Random Coefficient-Moving Product Based Wireless Key Generation

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China Communications 2025年第2期22卷 199-212页

作者： lu Xinjin Lei Jing Li Wei College of Electronic Science and Technology National University of Defense TechnologyChangsha 410073China State Key Laboratory of Complex Electromagnetic Environment Effects on Electronics and Information System Luoyang 471003China China South Industries Group Corporation Zhi Yuan Institute310012China

The physical layer key generation technique provides an efficient method,which utilizes the natural dynamics of wireless ***,there are some extremely challenging security scenarios such as static or quasi-static environment,which lead to the low randomness of generated ***,the coefficients of the static channel may be dropped into the guard space and discarded by the quantization approach,which causes low key generation *** tackle these issues,we propose a random coefficient-moving product based wireless key generation scheme(RCMP-WKG),where new random resources with remarkable fluctuations can be obtained by applying random coefficient and by moving product on the legitimate ***,appropriate quantization approaches are used to increase the key generation ***,the security of our proposed scheme is evaluated by analyzing different attacks and the eavesdropper’s mean square error(MSE).The simulation results reveal that the proposed scheme can achieve better performances in key capacity,key inconsistency rate(KIR)and key generation rate(KGR)compared with the prior works in static ***,the proposed scheme can deteriorate the MSE performance of the eavesdropper and improve the key generation performance of legitimate nodes by controlling the length of the moving product.

关键词： moving product random coefficient static environment wireless key generation

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Tail Dependence Matrices and Tests Based on Spearman's ρ and Kendall's τ

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Acta Mathematica Sinica,English Series 2025年第2期41卷 522-546页

作者： Lingyue Zhang Dawei lu Hengjian Cui School of Mathematical Sciences Capital Normal UniversityBeijing 100048P.R.China School of Mathematical Sciences Dalian University of TechnologyDalian 116024P.R.China

Measuring and testing tail dependence is important in finance, insurance, and risk management. This paper proposes two tail dependence matrices based on classic rank correlation coefficients,which possess the desired population properties and interpretability. Their nonparametric estimators with strong consistency and asymptotic distributions are derived using the limit theory of *** simulation and application studies show that, compared to the tail dependence matrix based on Spearman's ρ with large deviation, the Kendall-based tail dependence measure has stable variances under different tail conditions;thus, it is an effective approach to testing and quantifying tail dependence between random variables.

关键词： Tail dependence Spearman's Kendall's -statistic Copula

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GFRF R-CNN:Object Detection Algorithm for Transmission Lines

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Computers, Materials & Continua 2025年第1期82卷 1439-1458页

作者： Xunguang Yan Wenrui Wang Fanglin lu Hongyong Fan Bo Wu Jianfeng Yu Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai201210China University of Chinese Academy of Sciences Beijing100049China Jingwei Textile Machinery Co. Ltd.Beijing100176China

To maintain the reliability of power systems,routine inspections using drones equipped with advanced object detection algorithms are essential for preempting power-related *** increasing resolution of drone-captured images has posed a challenge for traditional target detection methods,especially in identifying small objects in high-resolution *** study presents an enhanced object detection algorithm based on the Faster Regionbased Convolutional Neural Network(Faster R-CNN)framework,specifically tailored for detecting small-scale electrical components like insulators,shock hammers,and screws in transmission *** algorithm features an improved backbone network for Faster R-CNN,which significantly boosts the feature extraction network’s ability to detect fine *** Region Proposal Network is optimized using a method of guided feature refinement(GFR),which achieves a balance between accuracy and *** incorporation of Generalized Intersection over Union(GIOU)and Region of Interest(ROI)Align further refines themodel’s *** results demonstrate a notable improvement in mean Average Precision,reaching 89.3%,an 11.1%increase compared to the standard Faster *** highlights the effectiveness of the proposed algorithm in identifying electrical components in high-resolution aerial images.

关键词： Faster R-CNN transmission line object detection GIOU GFR

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Parameterized Littlewood-Paley Operators and Their Commutators on Two-Weight Grand Homogeneous Variable Herz-Morrey Spaces

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Journal of Mathematical Research with Applications 2025年第2期 231-242页

作者： Xijuan CHEN Wenwen TAO Guanghui lu College of Mathematics and Statistics Northwest Normal University

In this paper,the authors prove that the parameterized area integral μΩ,Sρand the parameterized Littlewood-Paley gδ*-function μΩ,δ*,ρare bounded on two-weight grand homogeneous variable Herz-Morrey spaces MKp,θ,q（·）)α（·）,λ（ω1,ω2）,where θ>0,λ∈（2,∞）,q（·）∈B（R~n）,α（·）∈L∞（R~n）,ω1∈Apω1for pω1∈[1,∞] and ω2is a ***,the authors prove that the commutators [b,μΩ,Sρ] which is formed by b∈BMO（R~n） and the μΩ,Sρ,and the [b,μΩ,δ*,ρ] generated by b∈BMO（R~n） and the μΩ,δ*,ρare bounded on MKp,θ,q（·）)α（·）,λ（ω1,ω2）,respectively.

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