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基于时空融合算法的水体叶绿素a反演研究

水文 2024年第2期44卷 26-33页

作者：陈玲董晓华马耀明章程焱薄会娟三峡大学水利与环境学院湖北宜昌443002 三峡库区生态环境教育部工程研究中心湖北宜昌443002 中国科学院青藏高原研究所青藏高原地球系统与资源环境国家重点实验室地气作用与气候效应团队北京100101 中国科学院大学地球与行星科学学院北京100049 兰州大学大气科学学院甘肃兰州730000 西藏珠穆朗玛特殊大气过程与环境变化国家野外科学观测研究站西藏定日858200 中国科学院加德满都科教中心北京100101 中国科学院中国-巴基斯坦地球科学研究中心伊斯兰堡巴基斯坦45320

为了准确反演水体中叶绿素a浓度,以黄柏河东支流域为例,采用STNLFFM时空融合算法,对2017年GF-4和Sentinel-2反射率数据进行融合,以重构Sentinel-2影像的时间序列数据,并对应用算法前后获取的水质参数-光谱特征响应关系建立多元线性回归... 详细信息

为了准确反演水体中叶绿素a浓度,以黄柏河东支流域为例,采用STNLFFM时空融合算法,对2017年GF-4和Sentinel-2反射率数据进行融合,以重构Sentinel-2影像的时间序列数据,并对应用算法前后获取的水质参数-光谱特征响应关系建立多元线性回归模型,比较模型对叶绿素a的预测效果以验证时空融合算法的可行性,利用重构后影像光谱特征与水质参数的响应关系建立人工神经网络模型,反演2017年黄柏河东支流域各水库水体叶绿素a浓度。结果表明:利用时空融合算法生成的影像接近真实影像,提高了多元线性回归模型预测叶绿素a的效果,R2从融合前0.659提高至融合后0.844,且基于时空融合算法获取的水质参数-光谱关系建立的人工神经网络模型模拟精度较好,R2和MRE达到0.925和9.461%,反演的叶绿素a浓度空间差异性明显。证明了时空融合算法在水质参数反演过程中具有较好的应用前景。

关键词： STNLFFM时空融合算法黄柏河人工神经网络水质反演叶绿素a

Osthole improves synaptic plasticity in the hippocampus and cognitive function of Alzheimer's disease rats via regulating glutamate

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Neural Regeneration Research 2012年第30期7卷 2325-2332页

作者： xiaohua dong Li Zhang Wei Li Xianyong Meng Department of Pharmacology College of Pharmacy Hebei Medical University Shijiazhuang 050017 Hebei Province China Department of Pharmacology School of Medicine Hebei North University Zhangjiakou 075000 Hebei Province China Department of Orthopedics the First Attached Hospital Hebei North University Zhangjiakou 075000 Hebei Province China

Osthole, an effective monomer in Chinese medicinal herbs, can cross the blood-brain barrier and protect against brain injury, with few toxic effects. In this study, a rat model of Alzheimer＇s disease was established after intracerebroventricular injection of β-amyloid peptide （25-35）. Subsequently the rats were intraperitoneally treated with osthole （12.5 or 25.0 mg/kg） for 14 successive days. Results showed that osthole treatment significantly improved cognitive impairment and protected hippocampal neurons of AIzheimer＇s disease rats. Also, osthole treatment alleviated suppressed long-term potentiation in the hippocampus of Alzheimer＇s disease rats. In these osthole-treated Alzheimer＇s disease rats, the level of glutamate decreased, but there was no significant change in y-amino-butyric acid. These experimental findings suggest that osthole can improve learning and memory impairment, and increase synaptic plasticity in Alzheimer＇s disease rats. These effects of osthole may be because of its regulation of central glutamate and y-amino-butyric acid levels.

关键词： osthole Alzheimer's disease learning and memory long-term potentiation glutamate y-amino-butyric acid β-amyloid peptide brain hippocampus neural regeneration

Dynamic Replication Strategies in Data Grid

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Wuhan University Journal of Natural Sciences 2008年第4期13卷 440-444页

作者： dong xiaohua wu Zhongfu College of Computer Science Chongqing UniversityChongqing 400030 China School of Economics and Business Administrator Chongqing University Chongqing 400030 China

Dynamic data replication is a technique used in data grid environments that helps to reduce access latency and network bandwidth utilization. Replication also increases data availability thereby enhancing system reliability. In this paper we discuss the issues with single-location strategies in large-scale data integration applications, and examine potential multiple-location schemes. Dynamic multiple-location replication is NP-complete in nature. We therefore transform the multiple-location problem into several classical mathematical problems with different parameter settings, to which efficient approximation algorithms apply experimental results indicate that unlike single-location strategies our multiple-location schemes are efficient with respect to access latency and bandwidth consumption, especially when the requesters of a data set are distributed over a large scale of locations.

关键词： data grid approximation algorithms dynamic datareplication multiple-location replication

Focalizations and Their Functions in Heart of Darkness

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兰州大学学报（社会科学版） 2000年第S1期28卷 109-113页

作者： dong xiaohua (Foreign Languages Department, Northwest Normal University, Lanzhou, 730070, China)

As an important technique involved in the novel writing,the focalization is studied in detail in *** paper is an attempt to analyze the arrangement of focalizations and their functions in Heart of Dartness according t... 详细信息

关键词： focalizations narratology functions

Distributed Platooning Control of Automated Vehicles Subject to Replay Attacks Based on Proportional Integral Observers

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IEEE/CAA Journal of Automatica Sinica 2024年第9期11卷 1954-1966页

作者： Meiling Xie Derui Ding xiaohua Ge Qing-Long Han Hongli dong Yan Song Department of Control Science and Engineering University of Shanghai for Science and TechnologyShanghai 200093China School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyMelbourne VIC 3122Australia Artificial Intelligence Energy Research Institute Northeast Petroleum UniversityDaqing 163318the Heilongjiang Provincial Key Laboratory of Networking and Intelligent ControlNortheast Petroleum UniversityDaqing 163318 Sanya Offshore Oil&Gas Research Institute Northeast Petroleum UniversitySanya 572024China

Secure platooning control plays an important role in enhancing the cooperative driving safety of automated vehicles subject to various security *** paper focuses on the distributed secure control issue of automated vehicles affected by replay attacks.A proportional-integral-observer(PIO)with predetermined forgetting parameters is first constructed to acquire the dynamical information of ***,a time-varying parameter and two positive scalars are employed to describe the temporal behavior of replay *** light of such a scheme and the common properties of Laplace matrices,the closed-loop system with PIO-based controllers is transformed into a switched and time-delayed ***,some sufficient conditions are derived to achieve the desired platooning performance by the view of the Lyapunov stability *** controller gains are analytically determined by resorting to the solution of certain matrix inequalities only dependent on maximum and minimum eigenvalues of communication ***,a simulation example is provided to illustrate the effectiveness of the proposed control strategy.

关键词： Automated vehicles platooning control proportional-integral-observers(PIOs) replay attacks time-delays

基于模态结构应力法的焊接构架振动疲劳寿命研究

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机车车辆工艺 2024年第3期60卷 1-7页

作者：吕晓鹏邹洪伟董晓华李世杰吴兴文中车青岛四方机车车辆股份有限公司山东青岛266111 成都地铁运营有限公司四川成都610031 轨道交通运载系统全国重点实验室四川成都610031 西南交通大学机械工程学院四川成都610031

文章结合模态叠加法,提出了一种基于模态法的结构应力计算方法;然后基于刚柔耦合理论,建立了考虑构架柔性的刚柔耦合动力学模型,并利用虚拟激励法再现了转向架构架的真实服役环境,对服役条件下焊接构架的动态薄弱位置进行了识别,确定了... 详细信息

文章结合模态叠加法,提出了一种基于模态法的结构应力计算方法;然后基于刚柔耦合理论,建立了考虑构架柔性的刚柔耦合动力学模型,并利用虚拟激励法再现了转向架构架的真实服役环境,对服役条件下焊接构架的动态薄弱位置进行了识别,确定了焊接车架上的10个动态薄弱点,在连接侧梁外垂直板和下盖板的焊缝处观察到了最高的结构应力(均方根值为65 MPa)。最后,基于主S-N曲线法对焊接构架薄弱位置的服役寿命进行了预测。结果表明:随着曲线半径的增大,构架薄弱位置的损伤呈现出逐渐减小的规律;其损伤最大位置出现在侧梁外立板与抗侧滚扭杆座焊缝处,在1200万km的寿命要求下,其损伤为2.74,安全裕量较低。

关键词：焊接构架刚柔耦合动力学结构应力模态叠加法疲劳寿命预测

小核仁RNA宿主基因8在人类癌症中的研究进展

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宁夏医科大学学报 2024年第7期46卷 716-721页

作者：赵琪琪李渊于淼杜雪芹董晓骅孟云杨晓军宁夏医科大学银川750004 甘肃省人民医院普外科兰州730000 甘肃省外科肿瘤分子诊断与精准治疗重点实验室兰州730000 兰州大学第一临床医学院兰州730000 甘肃省消化道恶性肿瘤防控工程研究中心兰州730000

长链非编码RNA(long non-coding RNA,lncRNA)在人类癌症中具有重要作用。小核仁RNA宿主基因8(small nucleolar RNA host gene 8,SNHG8)被发现与多种人类疾病有关,如食管癌、肝癌、胃癌、心肌梗死等。基于以往对于SNHG8表达的研究,SNHG8... 详细信息

长链非编码RNA(long non-coding RNA,lncRNA)在人类癌症中具有重要作用。小核仁RNA宿主基因8(small nucleolar RNA host gene 8,SNHG8)被发现与多种人类疾病有关,如食管癌、肝癌、胃癌、心肌梗死等。基于以往对于SNHG8表达的研究,SNHG8可作为竞争性内源性RNA(competitive endogenous RNA,ceRNA)调节疾病的发生和进展,通过作用于相关miRNA及miRNA靶基因调节下游信号通路。此外,SNHG8的过表达与患者的临床特征密切相关,并通过不同作用机制调节肿瘤细胞的增殖、侵袭、转移以及抗凋亡。SNHG8在疾病发生和进展中的作用表明,SNHG8可作为疾病治疗、检测的新靶点或生物标志物。

关键词：癌症长链非编码RNA 小核仁RNA宿主基因8 生物标志物

A Pair of NLRs Coordinately Modulates NRC3-mediated ETI Responses to Facilitate Age-dependent Immunity

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A Pair of NLRs Coordinately Modulates NRC3-mediated ETI Resp...

中国植物病理学会2023年学术年会

作者： dong xiaohua AI Gan DOU Daolong Department of Plant Pathology Nanjing Agricultural University

Two NLRs adjacent to each other on a locus, termed as paired NLRs, may act separately for effector recognition and subsequent signaling activation to mediate effector-triggered immunity( ETI) in many ***, it is largely unknown about their distribution and functions in Solanaceae species, in which helper NLRs have been extensively ***, we identified paired NLRs in Solanaceae species and f ound they harbor paired NLRs ranging from 6 to 100, which are significantly negatively correlated with the numbers of *** has six paired NLRs, among which silencing of NRCX exhibits phenotypes of dwarfism and accelerated ***, NRCX-silencing phenotypes could be restored by simultaneously silencing its head-to-head NLR pair, thus we named it as NAR1(NRCX adjacent resistance protein 1).NRCX/NAR1 pair is specific in Solanaceae ***1 contains non-canonical walker B and MHD motifs, but could not induce autoactive cell death in *** of that, silencing NAR1 impaired cell death triggered by Sw5 b-Nsm and NRC3, indicating NAR1 is also an NLR modulator like ***, NRCX suppression of Sw5 b-Nsm and NRC3-mediated cell death is dependent on ***, we found that NRCX and NAR1 expressions were induced during plant maturation, while NAR1 was induced more than ***, the plant resistance was stronger during maturation, indicated NRCX/NAR1 might be involved in age-dependent *** study reveals one of the paired NLRs coordinately regulates ETI to facilitate age-dependent immunity.

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首都人才市场发展的回顾与展望

中国人力资源开发 2008年第11期25卷 101-103页

作者：董小华中国科学院研究生院

一、改革开放为首都人才市场发展注入了强大动力和支撑在改革开放初期，邓小平同志就强调，事情是由人去做的，没有人才是建不成四个现代化的：强调科学技术是第一生产力，要把科研和教育工作搞上去；强调人才难得，要尊重知识、尊重人... 详细信息

一、改革开放为首都人才市场发展注入了强大动力和支撑在改革开放初期，邓小平同志就强调，事情是由人去做的，没有人才是建不成四个现代化的：强调科学技术是第一生产力，要把科研和教育工作搞上去；强调人才难得，要尊重知识、尊重人才；强调我们现在的组织制度、人事制度阻碍人才的成长，要改革不合时宜的组织制度和人事制度。伴随着我们经济体制改革的逐步深入，

关键词：市场发展人才首都科学技术是第一生产力改革开放初期展望经济体制改革人事制度