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Isotopic characteristics and source analysis of atmospheric ammonia during agricultural periods in the Xichuan area of the Danjiangkou Reservoir

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Journal of Environmental Sciences 2024年第2期136卷 460-469页

作者： xiaoshu chen Tongqian Zhao Chunyan Xiao Xiaoming Guo Feihong chen Institute of Resources and Environment Henan Polytechnic UniversityJiaozuo 454000China

Nitrogen deposition is an important means of exogenous nitrogen input in reservoir *** activities around the reservoir lead to a sharp increase in the concentration of ammonia in the atmosphere,which poses a threat to the reservoir water *** the contribution of agricultural ammonia release to atmospheric NH_(x)(gaseous NH_(3)and particulate NH_(4)^(+)),in the reservoir area can provide a theoretical foundation for local reactive nitrogen *** collected atmospheric NH_(3)and NH_(4)^(+)samples during the agricultural periods and analyzed the isotopic characteristics of atmospheric NH_(x)and the contribution rates of different ammonia sources in the Xichuan area of the Danjiangkou *** results showed that the initialδ~(15)N values of NH_(3)(-30.0‰to–7.2‰)and particulate NH_(4)^(+)(–33‰to+4.9‰for finer and coarser particles,respectively)are different,and their contribution ratios from dissimilar ammonia sources are also different,among which NH_(4)^(+)is more susceptible to meteorological ***,since the atmospheric NH_(x)in the Xichuan area is mainly gaseous NH_(3),the final sources of atmospheric ammonia nitrogen source depend on gaseous NH_(3).Agricultural sources(59%-74%)were the main NH_(3)sources in this *** them,the fertilizer use emission was dominant;it had the highest contribution rate in summer during the agricultural period and a more prominent impact in areas with less human *** regulation of the application of high-ammonia releasing fertilizer,especially during the agricultural period in summer,is an effective way to reduce the threat of atmospheric ammonia to water health.

关键词： Danjiangkou reservoir Atmospheric ammonia nitrogen Isotope Ammonia source analysis Agricultural sources

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Robust Fingerprint Localization Based on Massive MIMO Systems

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China Communications 2022年第11期19卷 148-159页

作者： Xiaojun Wang Yijie Ren Weiguang Sun xiaoshu chen National Mobile Communications Research Laboratory Southeast UniversityNanjing 210000China Purple Mountain Laboratories Nanjing 210000China Frontiers Science Center for Mobile Information Communication and Security Southeast UniversityNanjing 210000China

Location-based services have become an important part of the daily *** localization has been put forward to overcome the shortcomings of the traditional positioning algorithms in indoor scenario and rich scattering *** this paper,a single-site multiple-input multiple-output(MIMO)orthogonal frequency division multiplexing(OFDM)system is modeled,from which an angle delay channel power matrix(ADCPM)is *** the changing environment,auto encoders are used to generate new fingerprints based on ADCPM fingerprints to improve the robustness of the *** the scattering environment has changed beyond a certain extent,the robustness will not be able to make up for the positioning *** this circumstance,an updating of the fingerprint database is imperative.A new fingerprint database updating algorithm which combines a new clustering method and an updating rule based on probability is *** results show the desirable performance of the proposed methods.

关键词： massive multiple-input multiple-output fingerprint extraction robustness database updating

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铁死亡的调控机制及其在蒽环类药物心脏毒性中的研究进展

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心血管病学进展 2024年第3期45卷 261-265页

作者：赵珂陈晓姝魏希进张娟刘杨卞雨敬袁杰山东中医药大学第一临床医学院山东济南250000 东明县卫生健康局山东菏泽274000 山东中医药大学附属医院山东济南250000

铁死亡是由铁介导的脂质过氧化累积引起的一种新的细胞死亡模式,在心血管疾病中发挥重要作用。蒽环类药物是最常用的化疗药物之一,用于治疗多种癌症。虽然药物有效,但其益处有时会受到急性和/或迟发性心脏毒性副作用(尤其是心力衰竭)的... 详细信息

铁死亡是由铁介导的脂质过氧化累积引起的一种新的细胞死亡模式,在心血管疾病中发挥重要作用。蒽环类药物是最常用的化疗药物之一,用于治疗多种癌症。虽然药物有效,但其益处有时会受到急性和/或迟发性心脏毒性副作用(尤其是心力衰竭)的影响。证据表明蒽环类药物心脏毒性与心肌细胞铁死亡密切相关,现就铁死亡在蒽环类药物心脏毒性发生过程中的机制及潜在的治疗靶点进行综述,以期为减弱蒽环类化疗药物所致心肌损伤提供新的治疗靶点与研究方向。

关键词：铁死亡蒽环类药物心脏毒性脂质过氧化铁积累

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The evolution of sex chromosome dosage compensation in animals

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Journal of Genetics and Genomics 2020年第11期47卷 681-693页

作者： Jiabi chen Menghan Wang Xionglei He Jian-Rong Yang xiaoshu chen Department of Biology and Medical Genetics Zhongshan School of MedicineSun Yat-sen UniversityGuangzhouChina State Key Laboratory of Biocontrol College of Life SciencesSun Yat-sen UniversityGuangzhouChina Department of Biomedical Informatics Zhongshan School of MedicineSun Yat-sen UniversityGuangzhouChina RNA Biomedical Institute Sun Yat-sen Memorial HospitalSun Yat-sen UniversityGuangzhouChina Program in Cancer Research Zhongshan School of MedicineThe Fifth Affiliated HospitalSun Yat-sen UniversityGuangzhouChina

The evolution of heteromorphic sex chromosomes shall lead to gene expression dosage problems,as in at least one of the sexes,the sex-linked gene dose has been reduced by *** has been proposed that the transcriptional output of the whole X or Z chromosome should be doubled for complete dosage compensation in heterogametic ***,owing to the variability of the existing methods to determine the transcriptional differences between sex chromosomes and autosomes(S:A ratios)in different studies,we collected more than 500 public RNA-Seq data set from multiple tissues and species in major clades and proposed a unified computational framework for unbiased and comparable measurement of the S:A ratios of multiple *** also tested the evolution of dosage compensation more directly by assessing changes in the expression levels of the current sex-linked genes relative to those of the ancestral sex-linked *** found that in mammals and birds,the S:A ratio is approximately 0.5,whereas in insects,fishes,and flatworms,the S:A ratio is approximately *** analysis showed that the fraction of dosage-sensitive housekeeping genes on the X/Z chromosome is significantly correlated with the S:A *** addition,the degree of degeneration of the Y chromosome may be responsible for the change in the S:A ratio in mammals without a dosage compensation *** observations offer unequivocal support for the sex chromosome insensitivity hypothesis in animals and suggest that dosage sensitivity states of sex chromosomes are a major factor underlying different evolutionary strategies of dosage compensation.

关键词： Dosage compensation Sex chromosome Genomic evolution

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Specificity of mRNA Folding and Its Association with Evolutionarily Adaptive mRNA Secondary Structures

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Genomics, Proteomics & Bioinformatics 2021年第6期19卷 882-900页

作者： Gongwang Yu Hanbing Zhu xiaoshu chen Jian-Rong Yang Program in Cancer Research Zhongshan School of MedicineThe Fifth Affiliated HospitalSun Yat-sen UniversityGuangzhou 510080China Department of Medical Informatics Zhongshan School of MedicineSun Yat-sen UniversityGuangzhou 510080China Zhongshan School of Medicine Sun Yat-sen UniversityGuangzhou 510080China Department of Genetics and Cell Biology Zhongshan School of MedicineSun Yat-sen UniversityGuangzhou 510080China RNA Biomedical Institute Sun Yat-Sen Memorial HospitalSun Yat-sen UniversityGuangzhou 510120China

The secondary structure is a fundamental feature of both non-coding RNAs(ncRNAs)and messenger RNAs(mRNAs).However,our understanding of the secondary structures of mRNAs,especially those of the coding regions,remains elusive,likely due to translation and the lack of RNA-binding proteins that sustain the consensus structure like those binding to ***,mRNAs have recently been found to adopt diverse alternative structures,but the overall functional significance remains *** hereby approach this problem by estimating the folding specificity,i.e.,the probability that a fragment of an mRNA folds back to the same partner once *** show that the folding specificity of mRNAs is lower than that of ncRNAs and exhibits moderate evolutionary ***,we find that specific rather than alternative folding is likely evolutionarily adaptive since specific folding is frequently associated with functionally important genes or sites within a *** analysis in combination with ribosome density suggests the ability to modulate ribosome movement as one potential functional advantage provided by specific *** findings reveal a novel facet of the RNA structurome with important functional and evolutionary implications and indicate a potential method for distinguishing the mRNA secondary structures maintained by natural selection from molecular noise.

关键词： Evolutionary genomics RNA secondary structure RNA folding specificity RNA alternative folding Ribosome density

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Relationships Between River Water Quality and Landscape Factors in Haihe River Basin, China: Implications for Environmental Management

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Chinese Geographical Science 2016年第2期26卷 197-207页

作者： XU Huashan ZHENG Hua chen xiaoshu REN Yufen OUYANG Zhiyun State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Institute of Resources and Environment Henan Polytechnic University

River water plays a key role in human health, and in social and economic development, and is often affected by both natural factors and human activities. An in-depth understanding of the role of these factors can help in developing an effective catchment management strategy to protect precious water resources. This study analyzed river water quality, patterns of terrestrial and riparian ecosystems, intensity of agricultural activities, industrial structure, and spatial distribution of pollutant emissions in the Haihe River Basin in China for the year of 2010, identifying the variables that have the greatest impact on river water quality. The area percentage of farmland in study area, the percentage of natural vegetation cover in the 1000-m riparian zone, rural population density, industrial Gross Domestic Product(GDP)/km^2, and industrial amino nitrogen emissions were all significantly correlated with river water quality(P < 0.05). Farming had the largest impact on river water quality, explaining 43.0% of the water quality variance, followed by the coverage of natural vegetation in the 1000-m riparian zone, which explained 36.2% of the water quality variance. Industrial amino nitrogen emissions intensity and rural population density explained 31.6% and 31.4% of the water quality variance, respectively, while industrial GDP/km^2 explained 26.6%. Together, these five indicators explained 67.3% of the total variance in water quality. Consequently, water environmental management of the Haihe River Basin should focus on adjusting agricultural activities, conserving riparian vegetation, and reducing industrial pollutant emissions by optimizing industrial structure. The results demonstrate how human activities drive the spatial pattern changes of river water quality, and they can provide reference for developing land use guidelines and for prioritizing management practices to maintain stream water quality in a large river basin.

关键词：水环境管理水环境质量海河流域景观因子污染物排放量国内生产总值植被覆盖率河流水质

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Development of Wheel-Legged Biped Robots:A Review

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Journal of Bionic Engineering 2024年第2期21卷 607-634页

作者： Xuefei Liu Yi Sun Shikun Wen Kai Cao Qian Qi xiaoshu Zhang Huan Shen Guangming chen Jiajun Xu Aihong Ji Lab of Locomotion Bioinspiration and Intelligent Robots College of Mechanical and Electrical EngineeringNanjing University of Aeronautics and Astronautics29 Yudao StreetNanjing210016China State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing210016China

The wheel-legged biped robot is a typical ground-based mobile robot that can combine the high velocity and high efficiency pertaining to wheeled motion and the strong,obstacle-crossing performance associated with legged *** robots have gradually exhibited satisfactory application potential in various harsh scenarios such as rubble rescue,military operations,and wilderness ***-legged biped robots are divided into four categories according to the open–close chain structure forms and operation task modes,and the latest technology research status is summarized in this *** hardware control system,control method,and application are analyzed,and the dynamic balance control for the two-wheel,biomimetic jumping control for the legs and whole-body control for integrating the wheels and legs are *** summary,it is observed that the current research exhibits problems,such as the insufficient application of novel materials and a rigid–flexible coupling design;the limited application of the advanced,intelligent control methods;the inadequate understanding of the bionic jumping mechanisms in robot legs;and the insufficient coordination ability of the multi-modal motion,which do not exhibit practical application for the wheel-legged biped ***,this study discusses the key research directions and development trends for the wheel-legged biped robots.

关键词： Wheel-legged biped robot Wheeled motion Legged motion Control strategy

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Secrecy energy efficiency optimization for AN-aided SWIPT system with power splitting receiver

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Science China(Information Sciences) 2019年第2期62卷 211-213页

作者： Gang WANG Yan LIN Chao MENG Wei HENG xiaoshu chen National Mobile Communications Research Laboratory Southeast University School of Communication Engineering Jinling Institute of Technology

Dear editor,Two emerging technologies of fifth generation wireless systems (5G), i.e., simultaneous wireless information and power transmission (SWIPT) and physical layer (PHY) security, are attracting considerable attention because they can reduce system energy consumption and can enhance network communication security, respectively [1–3]. These technologies have been jointly studied as secure SWIPT, and recent literatures have investigated the problems of secrecy rate maximization (SRM),

关键词： Secrecy energy efficiency optimization for AN-aided SWIPT system with power splitting receiver

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无线传感器网络补偿性代价生成树路由算法

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东南大学学报（自然科学版） 2009年第4期39卷 690-694页

作者：王霄峻陈晓曙东南大学移动通信国家重点实验室南京210096

针对无线传感器网络中的"热点"问题,采用分簇的拓扑控制方法,并就簇头多跳方式提出了一种贪婪算法,以此在簇头间形成一种基于传输代价的生成树.算法前提是不同簇的传感数据相关性较小,不能进行数据融合.生成过程中每一步都以最小化当前... 详细信息

针对无线传感器网络中的"热点"问题,采用分簇的拓扑控制方法,并就簇头多跳方式提出了一种贪婪算法,以此在簇头间形成一种基于传输代价的生成树.算法前提是不同簇的传感数据相关性较小,不能进行数据融合.生成过程中每一步都以最小化当前最大节点代价为原则加入新的节点,从而达到均衡簇头节点能量消耗,延长网络生存时间的目的.并且在代价计算中引入相对剩余能量因子,以进一步均衡节点能量异构情况下的能量消耗.仿真结果表明,与现有典型算法相比较,在大规模无线传感器的应用环境下,网络生存时间得到有效的延长,节点剩余能量的分布也更加合理.

关键词：无线传感器网络多跳分簇生成树代价

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替代面法和推算法在淅川库区氨氮干沉降评估中的适用性分析

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环境科学学报 2022年第12期42卷 423-431页

作者：陈晓舒赵同谦任玉芬肖春艳贺玉晓陈飞宏张清淼河南理工大学资源环境学院焦作454000 北京京津冀区域生态环境变化与综合治理国家野外科学观测研究站北京100085

农业源氨氮沉降是水库型水源地水体收到的重要的外源氮之一,其沉降量评估与来源识别是水体氮污染防控的重要依据.替代面法和推算法是大气氮素干沉降监测的两种常用方法.采用替代面法和推算法,于2019年9月—2020年8月对淅川库区周边设置... 详细信息

农业源氨氮沉降是水库型水源地水体收到的重要的外源氮之一,其沉降量评估与来源识别是水体氮污染防控的重要依据.替代面法和推算法是大气氮素干沉降监测的两种常用方法.采用替代面法和推算法,于2019年9月—2020年8月对淅川库区周边设置的5个大气监测点进行干沉降样品采集,测定了样品中氨氮浓度及其氮同位素,探讨了2种监测方法在氨氮干沉降通量估算及氨氮来源解析中的适用性.结果表明:替代面法获得的氨氮干沉降通量为推算法的1.4~2.1倍,2种监测方法获得的氨氮干沉降通量在时空变化趋势上具有一致性;推算法获得的δ^(15)N-NH_(4)^(+)较替代面法偏负,季均相差为11.1‰,时空差异显著.替代面法在获得淅川库区氨氮干沉降通量方面具有优势,受氨氮分馏影响,直接获得的δ^(15)N-NH_(4)^(+)值较初始源δ^(15)N-NH_(3)值存在较大偏差,影响溯源结果的准确性;推算法能够分别获得不同氨氮形态干沉降中的δ^(15)N-NH_(4)^(+)值,适用于氨氮干沉降来源分析,但易造成氨氮干沉降通量偏低;综合利用2种监测方法能够提高同位素溯源结果的准确性.

关键词：干沉降氨氮推算法替代面法水库型水源地农业

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