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Acta Mechanica Sinica 2011年第6期27卷 1052-1058页

作者： Qing-Yun Wang yan-hong zheng Department of Dynamics and Control Beihang University 100191 Beijing China School of Mathematics and Computer Science Fujian Normal University 350007 Fuzhou China

In this paper,we investigate the evolution of spatiotemporal patterns and synchronization transitions in dependence on the information transmission delay and ion channel blocking in scale-free neuronal *** the underlying model of neuronal dynamics,we use the Hodgkin-Huxley equations incorporating channel blocking and intrinsic *** is shown that delays play a significant yet subtle role in shaping the dynamics of neuronal *** particular,regions of irregular and regular propagating excitatory fronts related to the synchronization transitions appear intermittently as the delay ***,the fraction of working sodium and potassium ion channels can also have a significant impact on the spatiotemporal dynamics of neuronal *** the fraction of blocked sodium channels increases,the frequency of excitatory events decreases,which in turn manifests as an increase in the neuronal synchrony that,however,is dysfunctional due to the virtual absence of large-amplitude ***,we also show that larger coupling strengths improve synchronization irrespective of the information transmission delay and channel *** presented results are also robust against the variation of the network size,thus providing insights that could facilitate understanding of the joint impact of ion channel blocking and information transmission delay on the spatiotemporal dynamics of neuronal networks.

关键词： Scale-free neuronal networks - Information transmission delay Ion channel blocking Synchronization

Can increased economic complexity and reduced carbon emissions of the logistics industry go hand in hand?Evidence from countries along the Belt and Road

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Advances in Climate Change Research 2023年第5期14卷 789-797页

作者： Chong YE yan-hong zheng Xiao-Li HAN Shi-Jun CHEN School of Advanced Manufacturing Fuzhou UniversityJinjiang 362251China School of Politics and Public Administration Hainan UniveristyHaikou 570228China Chongming Carbon Neutrality Institute Tongji UniversityShanghai 200092China

At present,the main focus of research lies in examining the connection between economic complexity and carbon emissions as a whole,but there is a scarcity of quantitative investigations on the link between the above variables within specific ***,this study introduces economic complexity as a new variable to build a panel model within the traditional Environmental Kuznets Curve *** on the data of the countries along the Belt and Road from 1998 to 2018,we used the Granger causality test to examine the causal relationship between variables,and use the Fully Modified Ordinary Least Square and Dynamic Ordinary Least Square methods to estimate the coefficients of *** key factor linking economic complexity and carbon emissions in the logistics industry is technology innovation Economic complexity can explain and predict the changes in carbon emissions of logistics industry more reasonably,and the relationship between them in line with the environmental kuznets curve *** high-income countries can increase economic complexity while reducing carbon emissions of logistics *** on the empirical analysis,it is suggested that upper-middle income and lower middle-income countries can formulate relevant policies and regulations,and high-income countries can improve the relevant policies and regulations to promote the reduction of carbon emissions of the logistics *** the impact of economic complexity on carbon emissions in the logistics industry can help better predict and respond to the impact of climate change on the logistics industry.

关键词： Economic complexity Carbon emissions of logistics industry Belt and Road countries

Synthesis, Structure Characterization, and Cu^(2+) Recognition of 3-{[3-(Phenylsulfonamido)benzoyl]methylidene}-3,4-dihydroquinoxaline-2(1H)-one

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Chemical Research in Chinese Universities 2006年第6期22卷 747-752页

作者： LI Xue-mei ZENG Cheng-chu NIU Li-ting yan hong zheng Da-wei Zhong Ru-gang College of Life Science ＆ Bioengineering Beijing University of Technology Beijing 100022 P. R. China

Aryl diketo acid derivatives are one of the most promising HIV-1 integrase（IN） inhibitors. With a view to substitute the critical diketo acid pharmacophore with the diketo benzimidazole unit, the coupling reaction of compound 4 with o-phenylenediamine was carried out. However, the reaction product, compound 5, was confirmed to be 3-{ [ 3- （phenylsulfonamido） benzoyl] methylidene t -3,4-dihydroquinoxaline-2 （1H） -one rather than the 2-benzimidazole derivative by using X-ray diffraction. Owing to its low solubility in water, the evaluation of the anti-HIV IN activity of the synthesized compound 5 could not be carried out. Consequently, the ion-binding properties of compound 5 in the absence of HIV-1 IN were investigated with UV-Vis spectroscopy in organic solvents. The results show that such a compound can selectively recognize Cu^2＋.

关键词： Diketo acid Quinoxalone derivative X-ray crystal structure Cu^2+ recognition

Study on the modification of inclusions by Ca treatment in GCr18Mo bearing steel

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Advances in Manufacturing 2019年第4期7卷 438-447页

作者： hong-yan zheng Shu-Qiang Guo Meng-Ran Qiao Li-Bin Qin Xiu-Jing Zou Zhong-Ming Ren State Key Laboratory of Advanced Special Steel and Shanghai Key Laboratory of Advanced Ferrometallurgy and School of Materials Science and Engineering Shanghai UniversityShanghai 200444People's Republic of China

The effect of Ca treatment on the modification of inclusions in Al-killed GCr18Mo bearing steel was studied and a thermodynamic and kinetic model was *** experimental results showed that oxygen content in the steel could be reduced from 120ug/g to the range 5.5-21.6ug/g by Al-Ca complex deoxidization at 1873 *** appropriate increase in Ca/Al mass ratio is beneficial to reduce the total oxygen content in *** the content of dissolved aluminum was in the range of 0.03%-0.3%,w让h the increase of Ca/Al mass ratio from 0.8-1.6 to 2.4-3.2,the number of inclusions per unit area significantly *** addition,the main types of inclusions were modified from large-sized Al2O3 clusters to plastic or semiplastic liquid phase calcium *** experimental results matched well with the thermodynamic analysis.

关键词： GCr18Mo bearing steel-Ca treatment Inclusion modification Deoxidization Thermodynamics

Analysis of Synonymous Codon Usage Bias in Chlamydia

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Acta Biochimica et Biophysica Sinica 2005年第1期37卷 1-10页

作者： Hui L(?) Wei-Ming ZHAO~* yan zheng hong WANG Mei QI Xiu-Ping YU Department of Medical Microbiology,School of Medicine,Shangdong University,Jinan 250012,China Department of Medical Microbiology School of Medicine Shandong University Jinan 250012 China.

Chlamydiae are obligate intracellular bacterial pathogens that cause ocular and sexuallytransmitted diseases,and are associated with cardiovascular *** analysis of codon usage mayimprove our understanding of the evolution and pathogenesis of Chlamydia and allow reengineering of targetgenes to improve their expression for gene ***,we analyzed the codon usage of ***,***(here indicating biovar trachoma and LGV),***,and *** using the codonusage database and the CUSP(Create a codon usage table)program of EMBOSS(The European MolecularBiology Open Software Suite).The results show that the four genomes have similar codon usage patterns,with a strong bias towards the codons with A and T at the third codon *** with Homosapiens,the four chlamydial species show discordant seven or eight preferred *** ENC(effectivenumber of codons used in a gene)-plot reveals that the genetic heterogeneity in Chlamydia is constrained bythe G+C content,while translational selection and gene length exert relatively weaker ***,mutational pressure appears to be the major determinant of the codon usage variation among the *** addition,we compared the codon preferences of *** with those of ***,yeast,adenovirus and Homo *** are 23 codons showing distinct usage differences between *** ***,24 between *** and adenovirus,21 between *** and Homo sapiens,butonly six codons between *** and ***,the yeast system may be more suitable for theexpression of chlamydial ***,we compared the codon preferences of *** with those ofsix eukaryotes,eight prokaryotes and 23 *** is a strong positive correlation between the differ-ences in coding GC content and the variations in codon bias(r=0.905,P<0,001).We conclude that thevariation of codon bias between *** and other organisms is much less influenced b

关键词： Chlamydia codon usage bias GC content gene expression

The effect of the estradiol/testosterone ratio on CHD patients in postmenopausal women

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The effect of the estradiol/testosterone ratio on CHD patien...

基于粘-滑摩擦力模型的微型压电驱动器动力学分析

中华医学会第九次全国检验医学学术会议暨中国医院协会临床检验管理专业委员会第六届全国临床检验实验室管理学术会议

作者： Wen Dai,yan Li,hong Yun zheng Renmin Hospital of Wuhan University

Background Recently,coronary heart disease, ERT has been forced to *** supplement with testosterone can effectively decrease the adverse *** indicates that combine estrogen with testosterone may play important role in the therapy of CHD.(CHD) has been the increasing important public healthy *** replacement therapy has put into practice for a long time,however,because of its serious adverse reactions.

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上海交通大学学报 2004年第8期38卷 1328-1330页

作者：卢秋红颜国正上海交通大学电子信息与电气工程学院上海200030

提出了一种新型的靠摩擦力驱动的微型压电驱动器,采用粘-滑摩擦力模型对其进行了动力学分析.通过对比仿真结果和实验结果,得出了不同驱动信号下的驱动器动力学特性;改变驱动信号的频率和幅值,能够控制驱动器的运动方向和速度.仿真结果... 详细信息

提出了一种新型的靠摩擦力驱动的微型压电驱动器,采用粘-滑摩擦力模型对其进行了动力学分析.通过对比仿真结果和实验结果,得出了不同驱动信号下的驱动器动力学特性;改变驱动信号的频率和幅值,能够控制驱动器的运动方向和速度.仿真结果与试验结果吻合较好,证明该摩擦力模型能够对驱动器进行较为精确的理论分析.

关键词：压电驱动器摩擦粘-滑模型动力学分析

折半聚类算法在基于社会力的人群疏散仿真中的应用

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计算机应用 2017年第5期37卷 1491-1495,1511页

作者：李焱刘弘郑向伟山东师范大学信息科学与工程学院济南250014 山东省分布式计算机软件新技术重点实验室济南250014

运用社会力模型(SFM)模拟人群疏散之前,需要先对人群进行聚类分组;然而,k中心聚类(k-medoids)和统计信息网格聚类(STING)这两大传统聚类算法,在聚类效率和准确率上都不能满足要求。针对这个问题,提出了折半聚类算法(BCA)。该算法结合了... 详细信息

运用社会力模型(SFM)模拟人群疏散之前,需要先对人群进行聚类分组;然而,k中心聚类(k-medoids)和统计信息网格聚类(STING)这两大传统聚类算法,在聚类效率和准确率上都不能满足要求。针对这个问题,提出了折半聚类算法(BCA)。该算法结合了围绕中心点聚类和基于网格聚类两类方式,并利用二分法查找思想划分网格,不需要反复聚类。先将数据用二分法划分成网格,再根据网格内数据密度选出核心网格,接着以核心网格为中心将邻居网格聚类,最后按就近原则归并剩余网格。实验结果表明,在聚类时间上,BCA平均仅是STING算法的48.3%,不到k-medoids算法的14%;而在聚类准确率上,k-medoids算法平均仅是BCA的50%,STING算法平均也只是BCA的88%。因此,BCA无论在效率还是准确率上都明显优于STING和k-medoids算法。

关键词：聚类算法统计信息网格 k中心聚类人群疏散仿真社会力模型

CAESAR Ⅱ在压力管道安全评定中的应用

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石油化工设备 2017年第1期46卷 70-73页

作者：林远龙严正宏宁波市特种设备检验研究院浙江宁波315048

采用管道应力分析软件CAESAR Ⅱ对某条按《在用工业管道定期检验规程》评定为4级的原油压力管道进行了受力分析,并将分析结果用于GB/T 19624—2004《在用含缺陷压力容器安全评定》附录G的U因子评定法之中。

关键词：压力管道原油安全评定 CAESARⅡ

Endoplasmic reticulum stress and autophagy in cerebral ischemia/reperfusion injury:PERK as a potential target for intervention

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Neural Regeneration Research 2025年第5期20卷 1455-1466页

作者： Ju zheng Yixin Li Ting Zhang yanlin Fu Peiyan Long Xiao Gao zhengwei Wang Zhizhong Guan Xiaolan Qi Wei hong yan Xiao Key Laboratory of Endemic and Ethnic Diseases Ministry of Education&Key Laboratory of Medical Molecular Biology of Guizhou ProvinceGuizhou Medical UniversityGuiyangGuizhou ProvinceChina Guizhou Center for Disease Control and Prevention GuiyangGuizhou ProvinceChina Department of Histology and Embryology Guizhou Medical UniversityGuiyangGuizhou ProvinceChina Collaborative Innovation Center for Prevention and Control of Endemic and Ethnic Regional Diseases Co-constructed by the Province and Ministry GuiyangGuizhou ProvinceChina

Several studies have shown that activation of unfolded protein response and endoplasmic reticulum(ER)stress plays a crucial role in severe cerebral ischemia/reperfusion *** occurs within hours after cerebral ischemia,but the relationship between ER stress and autophagy remains *** this study,we established experimental models using oxygen-glucose deprivation/reoxygenation in PC12 cells and primary neurons to simulate cerebral ischemia/reperfusion *** found that prolongation of oxygen-glucose deprivation activated the ER stress pathway protein kinase-like endoplasmic reticulum kinase(PERK)/eukaryotic translation initiation factor 2 subunit alpha(e IF2α)-activating transcription factor 4(ATF4)-C/EBP homologous protein(CHOP),increased neuronal apoptosis,and induced ***,inhibition of ER stress using inhibitors or by si RNA knockdown of the PERK gene significantly attenuated excessive autophagy and neuronal apoptosis,indicating an interaction between autophagy and ER stress and suggesting PERK as an essential target for regulating *** autophagy with chloroquine exacerbated ER stress-induced apoptosis,indicating that normal levels of autophagy play a protective role in neuronal injury following cerebral ischemia/reperfusion *** from this study indicate that cerebral ischemia/reperfusion injury can trigger neuronal ER stress and promote autophagy,and suggest that PERK is a possible target for inhibiting excessive autophagy in cerebral ischemia/reperfusion injury.

关键词： apoptosis ATF4 autophagy C/EBP homologous protein cerebral ischemia/reperfusion injury eIF2α endoplasmic reticulum stress PERK