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西藏东部主要建群树种径向生长对极端干旱的响应差异

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生态学报 2024年第3期44卷 1221-1230页

作者：钟元郑嘉诚邱红岩吕利新中国科学院植物研究所植被与环境变化国家重点实验室北京100093 中国科学院大学北京100049

不同坡向、不同海拔树木生长对极端干旱事件的响应可能不同,然而这方面的认识不足。为此,选取西藏东部珠角拉山阴、阳坡的建群树种川西云杉(Picea likiangensis ***)和大果圆柏(Juniperus tibetica),在不同海拔高度建立了树轮宽度年表,... 详细信息

不同坡向、不同海拔树木生长对极端干旱事件的响应可能不同,然而这方面的认识不足。为此,选取西藏东部珠角拉山阴、阳坡的建群树种川西云杉(Picea likiangensis ***)和大果圆柏(Juniperus tibetica),在不同海拔高度建立了树轮宽度年表,分析了径向生长的气候响应,以及对极端干旱事件的抵抗力和恢复力。结果表明:阳坡大果圆柏和阴坡川西云杉的树木生长对气候的响应存在相似性,均与前一年3—6月、11—12月气温显著正相关,与当年4—5月气温显著负相关,与当年4—5月降水和帕尔默干旱指数(PDSI,Palmer Drought Severity Index)显著正相关(P<0.05)。阳坡大果圆柏的抵抗力显著低于阴坡川西云杉。随着海拔升高,阴坡川西云杉树木个体的抵抗力和恢复力均显著提高,而阳坡大果圆柏树木个体抵抗力、恢复力在不同海拔无显著区别。结合混合效应模型表明树木抵抗力主要受当年4—5月平均最高气温限制,树木恢复力主要受干旱事件后四年4-5月平均最高气温限制(P<0.01),说明生长季高温引起的极端干旱是树木径向生长下降的主要原因。

关键词：大果圆柏川西云杉径向生长气候响应极端干旱抵抗力恢复力

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基于多策略改进北方苍鹰算法的无人机路径规划

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保定学院学报 2024年第5期37卷 102-111页

作者：杨帆吕立新安徽商贸职业技术学院信息与人工智能学院安徽芜湖241002 菲律宾科技大学工业教育学院菲律宾马尼拉1000

为实现在复杂地域和障碍环境下无人机高效、安全飞行路径规划问题,以飞行距离、转向角度、飞行高度为性能指标,以地形、空域中的障碍为约束建立了无人机三维路径规划模型.智能算法在解决高维多约束情况下无人机路径规划问题时,存在初始... 详细信息

为实现在复杂地域和障碍环境下无人机高效、安全飞行路径规划问题,以飞行距离、转向角度、飞行高度为性能指标,以地形、空域中的障碍为约束建立了无人机三维路径规划模型.智能算法在解决高维多约束情况下无人机路径规划问题时,存在初始种群多样性差且分布不均、容易陷入局部最优解等局限性,对此提出了一种多策略改进的北方苍鹰算法(MINGO).该算法在初始化时借助Piecewise混沌映射有效地增强了初始种群的分布均匀性,借助Levy游走和随机扰动策略增强了种群的多样性和个体的质量,使算法快速且高精度的收敛,使用非线性收敛因子策略来有效平衡算法的全局和局部搜索能力,通过精英个体引导策略有效提升了算法的寻优效率.比较性的数值实验和仿真实验表明,MINGO具有更快的收敛速度和更高的寻优精度,处理复杂障碍环境下无人机三维路径规划问题具有非常明显的优势.

关键词：北方苍鹰算法自适应游走策略随机扰动策略精英个体引导策略无人机路径规划

菲律宾海夏季仔稚鱼表层分布及其与环境因子的关系

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上海海洋大学学报 2024年第4期33卷 946-959页

作者：吕莉欣赵恒权钟俊生王晓东叶旭昌刘志良上海海洋大学海洋动物系统分类与进化上海高校重点实验室上海201306 上海海洋大学海洋生物资源与管理学院上海201306 上海海洋大学船舶管理中心上海201306

为了探究菲律宾海夏季仔稚鱼表层分布及其与环境因子的关系,于2022年夏季在菲律宾海(11°N~19°N、129°E~138°E)设置了50个采样站位,用大型仔稚鱼网(口径1.3 m,网目0.5 mm)进行表层水平拖网调查。共采集到仔稚鱼38159尾,隶属14目21科5... 详细信息

为了探究菲律宾海夏季仔稚鱼表层分布及其与环境因子的关系,于2022年夏季在菲律宾海(11°N~19°N、129°E~138°E)设置了50个采样站位,用大型仔稚鱼网(口径1.3 m,网目0.5 mm)进行表层水平拖网调查。共采集到仔稚鱼38159尾,隶属14目21科56种。日间采集优势种为黄鳍金枪鱼和银灰半棱鳀,夜间采集优势种为银灰半棱鳀,昼夜共同优势种为银灰半棱鳀,占采集样本总数的97.05%。各站位仔稚鱼的总平均密度为292.43 ind./1000 m^(3),日间采集的平均密度为17.61 ind./1000 m^(3),夜间采集的平均密度为526.54 ind./1000 m^(3),昼夜密度分布存在显著差异,密度较高的站位主要分布在15°N附近海域,且均为夜间采集。典型相关分析(Canonical correlation analysis,CCA)表明,影响仔稚鱼分布的环境因子从强到弱依次为海表面盐度(Sea surface salinity,SSS)、海表面温度(Sea surface temperature,SST)和溶解氧(Dissolved oxygen,DO),优势种银灰半棱鳀的分布主要受SSS和DO的影响。研究表明,菲律宾海夏季仔稚鱼的种类组成丰富,表层分布不均匀,昼夜分布差异显著。本研究可为菲律宾海渔业资源评估、保护与利用提供科学依据。

关键词：仔稚鱼种类组成昼夜分布菲律宾海

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Changes of growth-climate relationships of Smith fir forests along an altitudinal gradient

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Jackknife Model Averaging for Quantile Single-Index Coefficient Model

林业研究（英文版） 2024年第5期 41页

作者： Jiacheng Zheng Jing Yang Hengfeng Jia lixin lyu Jiayang Langzhen Qi-Bin Zhang

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Journal of Systems Science & Complexity 2024年第4期37卷 1685-1713页

作者： SUN Xianwen ZHANG lixin School of Mathematical Sciences Zhejiang UniversityHangzhou 310058China School of Statistics and Mathematics Zhejiang Gongshang UniversityHangzhou 310018China

In the past two decades,model averaging,as a way to solve model uncertainty,has attracted more and more *** this paper,the authors propose a jackknife model averaging(JMA) method for the quantile single-index coefficient model,which is widely used in *** model misspecification,the model averaging estimator is proved to be asymptotically optimal in terms of minimizing out-of-sample quantile *** experiments are conducted to compare the JMA method with several model selections and model averaging methods,and the results show that the proposed method has a satisfactory *** method is also applied to a real dataset.

关键词： Final prediction error JMA criterion model averaging quantile loss single-index coefficient model

滑液支原体烯醇化酶在感染宿主中的反应原性和细胞黏附性

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中国兽医学报 2024年第1期44卷 88-96页

作者：徐彬孙玉王树于岩飞王晓丽马孙婷孙华伟张敬峰刘传敏吕立新冯志新熊祺琰邵国青张小飞欧阳伟江苏省农业科学院兽医研究所国家兽用生物制品工程技术研究中心/农业农村部兽用生物制品工程技术重点实验室/江苏省食品质量安全重点实验室-省部共建国家重点实验室培育基地江苏南京210014 兽用生物制品(泰州)国泰技术创新中心江苏泰州225300 江苏大学生命科学学院江苏镇江212013 江苏大学医学院江苏镇江212013 南京农业大学动物医学院江苏南京210095 江苏大学食品与生物工程学院江苏镇江212013

滑液支原体(Mycoplasma synoviae,MS)是一种重要的禽病病原,严重危害我国养禽业。本研究旨在分析MS烯醇化酶(enolase,Eno)参与病原致病和诱导感染宿主免疫相关的功能。对MS的Eno蛋白进行种内和种间同源性和进化树分析,并预测Eno的蛋白... 详细信息

滑液支原体(Mycoplasma synoviae,MS)是一种重要的禽病病原,严重危害我国养禽业。本研究旨在分析MS烯醇化酶(enolase,Eno)参与病原致病和诱导感染宿主免疫相关的功能。对MS的Eno蛋白进行种内和种间同源性和进化树分析,并预测Eno的蛋白结合位点和B细胞表位。MS Eno在不同MS菌株间同源性较高,且有别于其他物种。B细胞表位广泛分布在Eno蛋白的各个部分,且大都与预测的蛋白结合位点有重合。进行Eno原核表达和纯化,制备兔抗Eno多克隆抗血清。利用Western blot分析Eno在MS感染鸡或灭活苗免疫鸡中的反应原性。结果显示,MS Eno与兔抗Eno多克隆抗血清、兔抗MS多克隆抗血清、灭活疫苗(HN01株或YBF-MS1株)高免鸡血清、HN01强毒攻毒后阳性鸡血清、3个不同地方来源的临床阳性鸡血清均能发生反应,说明其在疫苗免疫和病原感染鸡中均表现有反应原性。利用菌落印迹和双荧光检测分析并证实Eno为外膜蛋白。利用间接免疫荧光和ELISA板结合试验分析Eno对鸡滑膜鞘细胞(synovial sheath cells,SSCs)是否具有黏附素作用。试验证实Eno对SSCs具有黏附作用,且此黏附作用具有Eno浓度依赖性。以上证明MS Eno在病原感染和灭活苗免疫鸡中具有反应原性,并作为外膜锚定的细胞黏附素参与对关键宿主细胞SSCs的黏附,为后续深入研究Eno的致病和免疫相关功能提供了重要参考。

关键词：滑液支原体烯醇化酶反应原性细胞黏附

Metal-organic-framework-derived copper-based catalyst for multicomponent C-S coupling reaction

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Chinese Journal of Chemical Engineering 2024年第6期70卷 1-8页

作者： lixin Chen Hui Zhang Linxi Hou Xin Ge Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan UniversityWuxi 214122China Department of Materials-Oriented Chemical Engineering School of Chemical EngineeringFuzhou UniversityFuzhou 350116China Qingyuan Innovation Laboratory Quanzhou 362801China

Copper-based metal-organic frameworks(Cu-MOFs)are a promising multiphase catalyst for catalyzing C-S coupling reactions by virtue of their diverse structures and ***,the unpleasant odor and instability of the organosulfur,as well as the mass-transfer resistance that exists in multiphase catalysis,have often limited the catalytic application of Cu-MOFs in C-S coupling *** this paper,a Cu-MOFs catalyst modified by cetyltrimethylammonium bromide(CTAB)was designed to enhance mass transfer by increasing the adsorption of organic substrates using the long alkanes of ***,elemental sulfur was used to replace organosulfur to achieve a highly efficient and atom-economical multicomponent C-S coupling reaction.

关键词： Design Copper-based metal-organic frameworks (Cu-MOFs) Adsorption C-S coupling reaction Multiphase reaction

Distributed user pairing and effective computation offloading in aerial edge networks

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Chinese Journal of Aeronautics 2024年第4期37卷 378-390页

作者： Wei LIANG Shuhui WEN lixin LI Jingjing CUI School of Electronics and Information Northwestern Polytechnical UniversityXi’an CN710072China The State Key Laboratory of Integrated Services Networks Xidian UniversityXi’an CN710126China School of Electronics and Computer Science University of SouthamptonSouthampton SO167NSUK

Future Sixth-Generation (6G) mobile communication networks extremely require the global connectivity and the ground Base Stations (BSs) are difficult to develop in some specific areas,such as mountainous ***,the aerial networks are the key framework for the future communications,in which the aerial vehicle could act as the access ***,Mobile Edge Computing (MEC) is also essential to enhance the data processing capabilities of aerial *** this paper,we study a comprehensive communication-computation resource management problem for jointly optimizing user pairing,power and time allocation in the MEC aided Cognitive Radio (CR) aerial networks,namely CR-MEC aerial ***,this multilevel optimization problem could be decomposed into the user pairing and power allocation as well as time allocation *** the conceived CR-MEC aerial networks,we propose a User Pairing and Computation Offloading Management Algorithm (UPCOMA) based on three-sided matching theory,aiming to minimize the system’s energy *** the first step of UPCOMA,multiple Primary Users (PUs) and Cognitive Users (CUs) on the ground negotiate to each other with the suitable power allocation coefficients and construct the stable user ***,the stable user pairs would match to a high altitude platform who act as the base station,which is for appropriately allocating Transmission Time Slots (TSs) at the second step of ***,a hybrid offloading mode is proposed in our conceived networks in order to support ground users to offload their tasks adaptively according to their individual ***,the simulation results reveal that the relative performance of UPCOMA is close to that of the Brute-Force Search Algorithm (BFSA) with low ***,the hybrid offloading mode with less energy consumption supports much more ground user pairs to offload tasks compared to the binary mode.

关键词： Aerial edge computing Binary offloading Cognitive radio Hybrid offloading Resource management

Diversity and ecological assembly process of aerobic anoxygenic phototrophic bacteria in a low irradiation area,Three Gorges Reservoir

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Journal of Environmental Sciences 2024年第9期143卷 116-125页

作者： lixin Huo Anran Ma Hong Liu Xingzu Wang Cheng Song Chongqing Institute of Green and Intelligent Technology Chinese Academy of SciencesChongqing 400714China Chongqing School University of Chinese Academy of SciencesCollege of Resources and EnvironmentChongqing 400714China Key Laboratory of Reservoir Aquatic Environment Chinese Academy of SciencesChongqing 400714China University of Chinese Academy of Sciences Beijing 100049China

Aerobic anoxygenic phototrophic bacteria(AAPB)are significant bacterial groups in aquatic ecosystems,known for their rapid growth and photoheterotrophic ***,the distribution and ecological assembly process of AAPB in low irradiation freshwater basins remain unclear,warranting further *** this study,we present the diversity,abundance,spatial variations,ecological process,and community interaction of AAPB in sediment of Three Gorges Reservoir(TGR)under low *** findings demonstrate the dominant genera of AAPB community that exist in the TGR area also are appeared in different waters,with some regional ***,the concentration of pufM gene,an indicator for AAPB,maintains a consistently high numerical level ranging from(2.21±0.44)×10^(4)to(9.98±0.30)×10^(7)gene copies/*** solar irradiation is suggested as the major factor affecting AAPB,it remains unclear whether and how AAPB differ between regions due to varying solar irradiation *** results show spatial differences between total bacteria and AAPB communities,with significant differences observed only in *** and environmental factor contributed less than 10%to the spatial difference of community,with sediment type and environmental factors being the key factors influencing microbial community *** stochastic process plays a dominant role in the aggregation and replacement of AAPB communities,among which the most contribution is dispersal *** AAPB network,Yoonia and Gemmobacter are the hubs for *** results valuable insights into the AAPB communities in TGR with low irradiation.

关键词： Three Gorges Reservoir(TGR) Aerobic anoxygenic phototrophic bacteria(AAPB) Bacterial community Null model Community assembly