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Evaluation of mental fatigue based on multipsychophysiological parameters and kernel learning algorithms

Chinese Science Bulletin 2008年第12期53卷 1835-1847页

作者： zhang Chong zheng ChongXun yu XiaoLin Key Laboratory of Biomedical Information Engineering of Education Ministry Xi'an Jiaotong University Xi'an 710049 China

Mental fatigue is an extremely sophisticated phenomenon, which is influenced by the environment, the state of health, vitality and the capability of recovery. A single parameter cannot fully describe it. In this paper, the effects of long time sustained low-workload visual display terminal (VDT) task on psychology are investigated by subjective self-reporting measures. Then power spectral indices of HRV, the P300 components based on visual oddball and wavelet packet parameters of EEG are combined to analyze the impacts of prolonged visual display terminal (VDT) activity on autonomic nervous system and cen-tral nervous system. Finally, wavelet packet parameters of EEG are extracted as the features of brain activity in different mental fatigue states. Kernel principal component analysis (KPCA) and support vector machine (SVM) are jointly applied to differentiate two states. The statistic results show that the level of both subjective sleepiness and fatigue increase significantly from pre-task to post-task, which indicate that the long time VDT task induces the mental fatigue to the subjects. The predominant activ-ity of autonomic nervous system of subjects turns to the sympathetic activity from parasympathetic activity after the task. The P300 components and wavelet packet parameters of EEG are strongly related with mental fatigue. Moreover, the joint KPCA-SVM method is able to effectively reduce the dimension-ality of the feature vectors, speed up the convergence in the training of SVM and achieve a high rec-ognition accuracy (87%) of mental fatigue state. Multipsychophysiological measures and KPCA-SVM method could be a promising tool for the evaluation of mental fatigue.

关键词：心理疲劳脑电图心率诊断方法

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Chemical Conversion of a Coumarin Derivative Containing Arylhydrazono: Crystal Structures and Fluorescence Properties

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Chinese Journal of Structural Chemistry 2019年第3期38卷 384-389页

作者： zhang zheng-yu NIU Zhi-Gang WANG En-Ju Key Laboratory of Tropical Medicinal Plant Chemistry of Ministry of Education College of Chemistry & Chemical Engineering Hainan Normal University

An arylhydrazono-containing coumarin derivative(1) can undergo chemical conversions in two modes. When in the presence of Cu^(2+), a Cu^(2+)-promoted cyclization reaction was observed in aqueous acetonitrile and gives compound 2, while a ring-opening reaction occurs to give compound 3 in the absence of Cu^(2+). Both 2 and 3 were characterized by single-crystal X-ray diffraction. Compound 2 crystallizes in monoclinic C2/c space group with a = 26.606(5), b = 5.8142(12), c = 26.906(5) ?, β = 103.41(3)°, Z = 8, F(000) = 1696, μ = 0.186 mm^(-1), R = 0.0487 and wR = 0.1129. Compound 3 crystallizes in monoclinic P21/n space group with a = 9.917(2), b = 13.644(3), c = 15.912(3) ?, β = 95.38(3)°, Z = 4, F(000) = 896, μ = 0.182 mm^(-1), R = 0.0769 and w R = 0.1617. The spectroscopic studies show that compound 2 exhibits strong fluorescence emission.

关键词： coumarin benzothiazole fluorescence crystal structure

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Effects of Enhanced UV-B Radiation on the Activity and Expression of Alternative Oxidase in Red Kidney Bean Leaves

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Journal of Integrative Plant Biology 2007年第9期49卷 1320-1326页

作者： Ming-Guang Zhao Ying-Gao Liu Li-Xin zhang Lin zheng yu-Rong Bi Key Laboratory of Add and Grassland Ecology Ministry of Education School of Life Sciences Lanzhou University Lanzhou 730000 China

An increase in ultraviolet （UV） B radiation on the earth＇s surface is a feature of current global climate changes. It has been reported that alternative oxidase （AOX） may have a protective role against oxidative stress induced by environmental stresses, such as UV-B. To better understand the characteristic tolerance of plants to UV-B radiation, the effects of enhanced UV-B radiation on the activity and expression of AOX in red kidney bean （Phaseolus vulgaris） leaves were investigated in the present study. The results show that the total respiration rate and AOX activity in red kidney bean leaves increased significantly during treatment with enhanced UV-B. However, cytochrome oxidase （COX） activity did not change significantly. The H2O2 content was also markedly increased and reached a maximum of 4.45 mmol·L^-1·g^-1 DW （dry weight） at 24 h of UV-B treatment, before dropping rapidly. Both alternative pathway content and alternative pathway activity were increased in the presence of exogenous H2O2. Immunoblotting analysis with anti-AOX monoclonal antibody revealed that expression of the AOX protein increased in red kidney bean leaves under enhanced UV-B radiation, reaching a peak at 72 h. In addition, AOX expression in red kidney bean leaves was induced by exogenous H2O2. These data indicate that the increase in AOX activity in red kidney bean leaves under enhanced UV-B radiation was mainly due to H2O2-induced AOX expression.

关键词： alternative oxidase red kidney bean respiration UV-B radiation

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QTL Mapping for Adult-Plant Resistance to Stripe Rust in a Common Wheat RIL Population Derived from Chuanmai 32/Chuanyu 12

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Journal of Integrative Agriculture 2012年第11期11卷 1775-1782页

作者： WU Ling XIA Xian-chun zheng You-liang zhang zheng-yu ZHU Hua-zhong LIU Yong-j ian YANG En-nian LI Shi-zhao HE Zhong-hu Crop Research Institute Sichuan Academy of Agricultural Science Chengdu 610066 P.R. China Institute of Crop Sciences National Wheat Improvement Center/The National Key Facility for Crop Gene Resources and Genetic Improvement Chinese Academy of Agricultural Sciences (CAAS) Beijing 100081 P.R.China Triticeae Research Institute Sichuan Agricultural University Chengdu 611130 P..R. China International Maize and Wheat Improvement Center (CIMMYT) China Office/Chinese Academy of Agricultural Sciences Beijing 100081 P.R China Plant Protection Institute Sichuan Academy of Agricultural Science Chengdu 610066 P.R.China College of Agriculture Siehuan Agricultural University Chengdu 611130 P.R.China

Stripe rust, caused by Puccinia striiformis f. sp. tritici, is a devastating wheat disease worldwide. The Chinese wheat cultivar Chuanmai 32 has shown stable resistance to stripe rust for 10 yr in Sichuan Province, a hotspot for stripe rust epidemics. The objective of the present study was to map quantitative trait loci （QTL） for adult-plant resistance （APR） to stripe rust in a population of 140 recombinant inbred lines （RILs） derived from Chuanmai 32/Chuanyu 12. Field trials were conducted in Chengdu and Yaan, Sichuan, from 2005 to 2008, providing stripe rust reaction data for 6 environments. 797 simple sequence repeat （SSR） markers were screened for association with stripe rust reaction, initially through bulked segregant analysis （BSA）. Based on the mean disease values averaged across environments, the broad-sense heritability of maximum disease severity （MDS） was 0.75. Two QTLs for stripe rust resistance were detected by composite interval mapping （CIM）. They were designated ***-3BL and ***-3BS and explained from 6.6 to 20.1%, respectively, of the phenotypic variance across environments. ***-3BL came from Chuanmai 32; ***-3BS with lower effect was from the susceptible parent Chuanyu 12. Both QTLs appear to be new.

关键词： APR Triticum aestivum microsatellites quanitative trait locus yellow rust

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Genomic Sequence Determination of Classical Swine Fever Virus Persistent Infection Strain

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Wuhan University Journal of Natural Sciences 2001年第4期6卷 864-866页

作者： Wu Hai\|xiang, zhang Chu\|yu , zheng Cong yi, Guo Jun qing Institute of Virology, Wuhan University, Wuhan, 430072 Institute of Virology Wuhan University Wuhan

Full genomic sequence of a newly isolated persistent infection strain of classical swine fever virus was firstly determined. It was demonstrated by sequence analyses that nucleotides homologies of this strain compared with virulent Shimen and vaccine HCLV were 89.7%and 87.7%, and homologies of amino acids were 94.8%and 93.3%, respectively. The sequencing results primarily suggest a tighter relationship between this persistent infection strain and virulent Shimen strain than vaccine HCLV strain.

关键词： Classical Swine Fever Virus(CSFV) genomic sequence sequence analysis

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PpMAPK6 regulates peach bud endodormancy release through interactions with PpDAM6

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Journal of Integrative Agriculture 2023年第1期22卷 139-148页

作者： zhang yu-zheng XU Chen LU Wen-li WANG Xiao-zhe WANG Ning MENG Xiang-guang FANG yu-hui TAN Qiu-ping CHEN Xiu-de FU Xi-ling LI Ling College of Horticultural Science and Engineering Shandong Agricultural UniversityTai’an 271018P.R.China State Key Laboratory of Crop Biology Shandong Agricultural UniversityTai’an 271018P.R.China Shandong Collaborative Innovation Center for Fruit&Vegetable Production with High Quality and Efficiency Tai’an 271018P.R.China

The MADS-box(DAM)gene PpDAM6,which is related to dormancy,plays a key role in bud endodormancy release,and the expression of PpDAM6 decreases during endodormancy ***,the interaction network that governs its regulation of the endodormancy release of flower buds in peach remains *** this study,we used yeast two-hybrid(Y2H)assays to identify a mitogen-activated protein kinase,PpMAPK6,that interacts with PpDAM6 in a peach dormancy-associated SSHcDNA ***6 is primarily located in the nucleus,and Y2H and bimolecular fluorescence complementation(BiFC)assays verified that PpMAPK6 interacts with PpDAM6 by binding to the MADS-box domain of *** real-time PCR(qRT-PCR)analysis showed that the expression of PpMAPK6 was opposite that of PpDAM6 in the endodormancy release of three cultivars with different chilling requirements(Prunus persica‘Chunjie’,Prunus persica ***‘Zhongyou 5’,Prunus persica‘Qingzhou peach’).In addition,abscisic acid(ABA)inhibited the expression of PpMAPK6 and promoted the expression of PpDAM6 in flower *** results indicated that PpMAPK6 might phosphorylate PpDAM6 to accelerate its degradation by interacting with *** expression of PpMAPK6 increased with decreasing ABA content during endodormancy release in peach flower buds,which in turn decreased the expression of PpDAM6 and promoted endodormancy release.

关键词： peach endodormancy release PpDAM6 PpMAPK6 ABA

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Influence of introducing Zr,Ti,Nb and Ce elements on externally solidified crystals and mechanical properties of high-pressure die-casting Al–Si alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 147-153页

作者： Junjie Li Wenbo yu Zhenyu Sun Weichen zheng Liangwei zhang Yanling Xue Wenning Liu Shoumei Xiong Center of Materials Science and Engineering School of Mechanical and Electronic Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Traffic&Transportation Engineering Central South UniversityChangsha 410075China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

High pressure die casting(HPDC)AlSi10Mn Mg alloy castings are widely used in the automobile *** can optimize the mechanical properties of castings through heat treatment,while the release of thermal stress arouses the deformation of large integrated ***,the development of non-heat treatment Al alloys is becoming the hot *** addition,HPDC contains externally solidified crystals(ESCs),which are detrimental to the mechanical properties of *** achieve high strength and toughness of non-heat treatment die-casting Al-Si alloy,we used AlSi9Mn alloy as matrix with the introduction of Zr,Ti,Nb,and *** influences on ESCs and mechanical properties were systematically investigated through three-dimensional reconstruction and thermodynamic *** results reveal that the addition of Ti increased ESCs'size and porosity,while the introduction of Nb refined ESCs and decreased ***,large-sized Al_3(Zr,Ti)phases formed and degraded the mechanical *** introduction of Ce resulted in the poisoning effect and reduced mechanical properties.

关键词： aluminium alloy high-pressure die-casting externally solidified crystals non-heat treatment

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A framework of the suggested Meta-cognitive Strategy Training model

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Sino-US English Teaching 2010年第7期7卷 31-34页

作者： zhang Xiao-hui zheng yu-rong Foreign Languages Department Harbin Engineering University Heilongjiang 1500001 China

It is of great significance to carry out Meta-cognitive Strategy Training （MST） in current college English teaching context. After analyzing the advantages and disadvantages of some sequences and models for strategy training, the authors suggest the Meta-cognitive Strategy Training model which consists of 6 steps with Strategies-Based Instruction （SBI） employed to conduct the concrete strategy training.

关键词： meta-cognitive strategies strategy training college English teaching

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Intestinal Microbial Community Differs between Acute Pancreatitis Patients and Healthy Volunteers

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Biomedical and Environmental Sciences 2018年第1期31卷 81-86页

作者： zhang Xi Mei zhang zheng yu zhang Chen Huan WU Jing WANG You Xin zhang Guo Xin Department of Gastroenterology Nanjing First Hospital Nanjing Medical University Nanjing 210006 Jiangsu China School of Public Health Medical College of Soochow University Suzhou 215000 Jiangsu China Ruike-donghua Translational Medicine Research Center Co. Beijing 100176 China Beijing Municipal Key Laboratory of Clinical Epidemiology School of Public Health Capital Medical University Beijing 100069 China Department of Gastroenterology The First Affliated Hospital of Nanjing Medical University Nanjing 210029 Jiangsu China

A case control study including 45 acute pancreatitis and 44 healthy volunteers was performed to investigate the association between intestinal microbial community and acute pancreatitis. High-throughput 16S r RNA gene amplicon sequencing was used to profile the microbiological composition of the samples. In total, 27 microbial phyla were detected and the samples of pancreatitis patients contained fewer phyla. Samples from acute pancreatitis patients contained more Bacteroidetes and Proteobacteria and fewer Firmicutes and Actinobacteria than those from healthy volunteers. PCo A analyses distinguished the fecal microbial communities of acute pancreatitis patients from those of healthy volunteers. The intestinal microbes of acute pancreatitis patients are different from those of healthy volunteers. Modulation of the intestinal microbiome may serve as an alternative strategy for treating acute pancreatitis.

关键词： Intestinal Microbial Community Differs Acute Pancreatitis Patients

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用于TD-LTE系统的排序串行干扰消除迭代检测译码

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应用科学学报 2012年第1期30卷 19-24页

作者：张正宇邱玲中国科学技术大学个人通信与扩频实验室合肥230027

针对时分长期演进多输入多输出系统中的多码字传输模式,分析自适应调制编码和混合自动请求重传对排序串行干扰消除检测顺序的影响,提出一种新型的排序串行干扰消除迭代检测译码算法,并分析该算法的复杂度.仿真结果表明该算法能够有效提... 详细信息

针对时分长期演进多输入多输出系统中的多码字传输模式,分析自适应调制编码和混合自动请求重传对排序串行干扰消除检测顺序的影响,提出一种新型的排序串行干扰消除迭代检测译码算法,并分析该算法的复杂度.仿真结果表明该算法能够有效提高系统吞吐量,且码字调制编码等级差异越大,MIMO阶数越高,该算法的性能增益越明显.

关键词：多输入多输出自适应调制编码混合自动请求重传干扰消除迭代检测译码

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