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Journal of Integrative Agriculture 2014年第1期13卷 31-39页

作者： YU Ma MAO Shuang-lin CHEN Guo-yue LIU Ya-xi LI Wei WEI Yu-ming LIU Chun-ji zheng you-liang Triticeae Research Institute Sichuan Agricultural University Agronomy College Sichuan Agricultural University CSIRO Plant Industry

Waterlogging is a widespread limiting factor for wheat production throughout the world. To identify quantitative trait loci （QTLs） associated with waterlogging tolerance at early stages of growth, survival rate （SR）, germination rate index （GRI）, leaf chlorophyll content index （CCI）, root length index （RLI）, plant height index （PHI）, root dry weight index （RDWI）, shoot dry weight index （SDWI）, and total dry weight index （DWI） were assessed using the International Triticeae Mapping Initiative （ITMI） population W7984/Opata85. Significant and positive correlations were detected for all traits in this population except RLI. A total of 32 QTLs were associated with waterlogging tolerance on all chromosomes except 3A, 3D, 4B, 5A, 5D, 6A, and 6D. Some of the QTLs explained large proportions of the phenotypic variance. One of these is the QTL for GRI on 7A, which explained 23.92% of the phenotypic variation. Of them, 22 alleles from the synthetic hexaploid wheat W7984 contributed positively. These results suggested that synthetic hexaploid wheat W7984 is an important genetic resource for waterlogging tolerance in wheat. These alleles conferring waterlogging tolerance at early stages of growth in wheat could be utilized in wheat breeding for improving waterlogging tolerance.

关键词： wheat waterlogging tolerance QTL germination and seedling stages

Randomized Clinical Trials of Traditional Chinese Medicines for Treating Ulcerative Colitis:A Scoping Review

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World Journal of Traditional Chinese Medicine 2021年第3期7卷 326-331页

作者： you-you zheng Xiao Wang Jiang-Tao Si Yu-Xin Sun Wen-Bin Hou Jian-Ping Liu Yuan-Xi Li Zhao-Lan Liu Center for Evidence-Based Chinese Medicine Beijing University of Chinese Medicine Special Treatment Center Wang Jing Hospital of Chinese Academy of Traditional Chinese Medicine College of Statistics and Data Science Faculty of ScienceBeijing University of TechnologyBeijing 100124China

Objective:Traditional Chinese medicines(TCMs)are efficacious against ulcerative colitis(UC).In recent years,the number of randomized clinical trials(RCTs)of TCM has ***,it is very important to summarize the basic characteristics,quality,and types of TCM interventions in published *** scoping review was performed to systematically identify and describe the current situations about RCTs of TCMs for treating *** to express the focus and specifics of nowadays research in TCM interventions in RCTs and evaluate their common disadvantages exposed to help advance in TCM *** and Methods:A scoping review was conducted according to the PRISMA extension for scoping *** searched two English databases and four Chinese databases from the date of establishment of each database to January *** from RCTs focusing on any TCM treatment for patients with UC were extracted and *** and characterization were performed by two independent reviewers using predefined *** discrepancies were resolved by consensus discussion with a third *** Excel 2010 was used to extract the following data from the included studies:(1)basic information of the included studies including research ID,article title,publication language,journal,year of publication,and funding information;(2)patient information including gender,age,disease course,disease stage,severity,sample size;and(3)information on intervention measures,types of intervention measures,drug dosage forms,and treatment ***:The search identified 2225 RCTs published between1987 and *** studies covered 36 provinces in *** time frame of the RCTs was<28 days in approximately one-third of the RCTs(647,29.08%).Only one RCT was published in *** three-quarters of RCTs(1665,74.83%)did not report the severity of the *** types of interventions were included in the RCTs:pharmacotherapy(2028,91.15%),nonpharmacotherapy(57,2.56%),and a

关键词： Dosage forms randomized clinical trial research status scoping review Traditional Chinese medicine ulcerative colitis

Evaluation of Genetic Diversity of Sichuan Common Wheat Landraces in China by SSR Markers

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Journal of Integrative Agriculture 2013年第9期12卷 1501-1511页

作者： LI Wei BIAN Chun-mei WEI Yu-ming LIU An-jun CHEN Guo-yue PU Zhi-en LIU Ya-xi zheng you-liang Key Laboratory of Crop Genetic Resources and Improvement in Southwest China Ministry of EducationSichuan Agricultural University College of Agronomy Sichuan Agricultural University Triticeae Research Institute Sichuan Agricultural University

Genetic diversity of 62 Sichuan wheat landraces accessions of China was investigated by agronomic traits and SSR markers. The landrace population showed the characters of higher tiller capability and more kernels/spike, especially tiller no./plant of six accessions was over 40 and kernels/spike of three accessions was more than 70. A total of 547 alleles in 124 polymorphic loci were detected with an average of 4.76 alleles per locus by 114 SSR markers. Parameters analysis indicated that the genetic diversity ranked as genome A 〉 genome B 〉 genome D, and the homoeologous groups ranked as 5〉4〉3〉1〉2〉7〉6 based on genetic richness （Ri）. Furthermore, chromosomes 2A, 1B and 3D had more diversity than that of chromosomes 4A, 7A and 6B. The variation of SSR loci on chromosomes 1B, 2A, 2D, 3B, and 4B implied that, in the past, different selective pressures might have acted on different chromosome regions of these landraces. Our results suggested that Sichuan common wheat landraces is a useful genetic resource for genetic research and wheat improvement.

关键词： genetic diversity SSR marker landraces wheat

Design and fabrication of an surface acoustic wave resonator based on AlN/4H-SiC material for harsh environments

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2017年第1期18卷 67-74页

作者： Wei-zhong WANG Ji LIANG Yong RUAN Wei PANG zheng you Collaborative Innovation Center for Micro/Nano Fabrication Device and System State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision Instrument Tsinghua University Beijing 100084 China State Key Laboratory of Precision Measurement Technology and lnstruments Tianjin University Tianjin 300072 China

Surface acoustic wave （SAW） sensors and micro-electromechanical system （MEMS） technology provide a promising solution for measurement in harsh environments such as gas turbines. In this paper, a SAW resonator （size： 1107μm× 721 μm） based on the AlN/4H-SiC multilayer structure is designed and simulated. A MEMS-compatible fabrication process is employed to fabricate the resonator. The results show that highly c-axis-oriented AlN thin films deposited on the 4H-SiC substrate are obtained, with that the diffraction peak of AlN is 36.10° and the lowest full width at half maximum （FWHM） value is only 1.19°. The test results of the network analyzer are consistent with the simulation curve, which is very encouraging and indicates that our work is a significant attempt to solve the measurement problems mainly including high temperature stability of sensitive structures and the heat transmission of leads in harsh environments. It is essential to get the best performance of SAW resonator, optimize and characterize the behaviors in high temperatures in future research.

关键词： Surface acoustic wave (SAW) resonator AlN/4H-SiC Harsh environment Micro-electromechanical system(MEMS) technology Gas turbine

Tetramethylpyrazine nitrone improved mitochondrial dysfunction, downregulated α-synuclein, and reduced neurodegeneration in Parkinson disease models

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中国药理学与毒理学杂志 2019年第10期 843-844页

作者： GUO Bao-jian zheng Cheng-you QIU Xiao-ling ZHANG Zai-jun Institute of New Drug Research and Guangzhou Key Laboratory of Innovative Chemical Drug Research in Cardiocerebrovascular Diseases Jinan University College of Pharmacy

OBJECTIVE The peroxisome proliferatoractivated receptor γ co-activator 1α(PGC-1α) and nuclear factor(erythroid-derived 2)-like 2(Nrf2) are key regulators controlling antioxidant defense, mitochondrial biogenesis and cellular proteostasis. Dysfunction of any of these processes has been implicated in the pathogenesis of Parkinson disease(PD). Activation of PGC-1α/Nrf2 might improve mitochondrial dysfunction, promote α-synuclein(α-syn) clearance, and attenuate degeneration of nigral dopaminergic neurons in PD. To test this, we used tetramethylpyrazine nitrone(TBN), a potent free radical scavenger, to activate PGC-1α/Nrf2 pathway. METHODS 1-Methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine(MPTP)-induced mouse model, unilateral intrastriatal injection of 6-hydroxydopamine(6-OHDA)-induced rat model, and transgenic mice overexpression of human A53 T mutant α-synuclein were used to evaluate TBN's therapeutic efficacy and to explore its mechanisms of action. RESULTS TBN protected against 1-methyl-4-phenylpyridinium(MPP+) and 6-OHDA insult in cultured primary midbrain neurons. TBN promoted α-syn clearance by autophagy and proteasomal pathways in the cell models overexpressed human A53 T mutant α-syn. In MPTP-treated mouse and unilateral 6-OHDA-lesioned rat, as well as in α-syn transgenic mouse model, TBN improved motor impairment, increased survive of nigra dopaminergic neurons, and elevated striatal dopamine level, while decreased the products of oxidative ***, TBN down-regulated α-syn level in the brain and serum of α-syn transgenic mice. These improvements in vitro and in vivo were associated with activation of PGC-1α/Nrf2 signal pathway, resulting in reduced oxidative stress, enhanced mitochondrial function, and increased protein clearance. CONCLUSION Our work demonstrates that activation of PGC-1α/Nrf2 by TBN can maintain the survival of nigral dopaminergic neurons, and might be disease-modifying in PD models, providing the critical rationale for further devel

关键词： tetramethylpyrazine nitrone Parkinson disease peroxisome proliferator-activated receptor γ co-activator 1α nuclear factor(erythroid-derived 2)-like 2 α-synuclein

基于AlN/α-SiC的声表面波谐振器应变响应特性

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清华大学学报（自然科学版） 2016年第10期56卷 1061-1065页

作者：陈硕尤政清华大学精密仪器系精密测试技术及仪器国家重点实验室北京100084

面向高温环境应用的微纳传感器在燃气轮机健康监控、地热井环境监控等领域具有广泛的应用前景。该文主要介绍了一种基于AlN薄膜和α-SiC衬底的声表面波谐振器,讨论了谐振器的应变敏感性来源,提出了一种基于应变场-波速关系计算谐振器应... 详细信息

面向高温环境应用的微纳传感器在燃气轮机健康监控、地热井环境监控等领域具有广泛的应用前景。该文主要介绍了一种基于AlN薄膜和α-SiC衬底的声表面波谐振器,讨论了谐振器的应变敏感性来源,提出了一种基于应变场-波速关系计算谐振器应变敏感系数的方法。采用微纳米加工工艺加工了谐振器,并进行了材料表征。测量了谐振器的应变敏系数:具有1.5μm厚AlN压电薄膜的AlN/α-SiC基声表面波谐振器在298K下应变敏感系数为0.515×10-6/με,与计算结果具有较好一致性。

关键词：声表面波谐振器氮化铝碳化硅应变响应

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基于多层前馈网络的卫星姿态控制器

清华大学学报（自然科学版） 2005年第2期45卷 166-169页

作者：董哲尤政清华大学精密仪器与机械学系北京100084

卫星姿态动力学系统与其线性化模型之间的误差会影响姿态控制的精度。应用多层前馈网络对该误差进行建模,并基于此模型和线性系统理论设计了一种新型的卫星姿态控制器,该控制器实现了卫星三轴解耦控制,并使卫星姿态动力系统与其线性化... 详细信息

卫星姿态动力学系统与其线性化模型之间的误差会影响姿态控制的精度。应用多层前馈网络对该误差进行建模,并基于此模型和线性系统理论设计了一种新型的卫星姿态控制器,该控制器实现了卫星三轴解耦控制,并使卫星姿态动力系统与其线性化模型的响应误差在最小二乘准则意义下最小。仿真结果表明在俯仰角、滚动角和偏航角机动量均为0.01rad情况下,控制器能够提供较高的控制精度。

关键词：姿态控制神经网络解耦控制

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超时策略动态阈值的阈值选择影响因素

哈尔滨工业大学学报 2013年第6期45卷 119-123页

作者：曹哲尤政清华大学精密测试技术及仪器国家重点实验室北京100084

为在能源有限的情况下增加系统运行时间,从动态电源管理的超时策略角度出发,探讨了超时策略中阈值选择的影响因素.在国内外动态电源管理策略的研究基础上,分析了超时策略中动态阈值策略与固定阈值策略的原理,完成了对现有的动态阈值策... 详细信息

为在能源有限的情况下增加系统运行时间,从动态电源管理的超时策略角度出发,探讨了超时策略中阈值选择的影响因素.在国内外动态电源管理策略的研究基础上,分析了超时策略中动态阈值策略与固定阈值策略的原理,完成了对现有的动态阈值策略的阈值选择影响因素的分析,得出了系统进入休眠与唤醒的能量消耗、电池放电电压大小、系统具体的应用环境三方面对阈值选择产生影响.证实了综合考虑阈值的三方面影响因素是找到最优阈值的捷径.

关键词：动态电源管理超时策略动态阈值影响因素阈值选择

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一类非线性不确定系统的鲁棒镇定

清华大学学报（自然科学版） 2006年第5期46卷 637-640页

作者：尤政董哲清华大学精密仪器与机械学系北京100084

由于实际中的一类非线性不确定系统可以建模为具有状态矩阵和输入矩阵不确定性并受非线性摄动的线性系统,将这类系统的鲁棒镇定问题转化为求解一个线性系统的H∞状态反馈控制问题。结果表明:若该H∞状态反馈控制问题有解,则原系统可以... 详细信息

由于实际中的一类非线性不确定系统可以建模为具有状态矩阵和输入矩阵不确定性并受非线性摄动的线性系统,将这类系统的鲁棒镇定问题转化为求解一个线性系统的H∞状态反馈控制问题。结果表明:若该H∞状态反馈控制问题有解,则原系统可以通过状态反馈实现鲁棒镇定。给出了状态反馈矩阵,还进一步给出了具体的仿真实例。仿真结果表明:该理论是可行的,且控制器实现了对这类非线性不确定系统的鲁棒镇定。

关键词：非线性系统不确定系统 H∞控制鲁棒镇定

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水平式隧穿磁强计的性能实验

清华大学学报（自然科学版） 2006年第2期46卷 203-205页

作者：汤学华尤政清华大学精密仪器与机械学系北京100084

水平式隧穿磁强计是一种新型隧穿磁强计,其特点是:反映磁场变化的Loren tz力与敏感元件在同一水平面内。对已加工的这种磁强计表头进行了性能实验。实验内容包括:通过隧道电流和驱动电压的测试实验来验证该表头是一种符合隧道效应的传感... 详细信息

水平式隧穿磁强计是一种新型隧穿磁强计,其特点是:反映磁场变化的Loren tz力与敏感元件在同一水平面内。对已加工的这种磁强计表头进行了性能实验。实验内容包括:通过隧道电流和驱动电压的测试实验来验证该表头是一种符合隧道效应的传感器;通过隧道电流和线圈电流的测试实验来验证该表头具有磁强计的基本功能。测试结果表明:这种磁强计符合隧道效应并能够敏感磁场信号。

关键词：传感器隧穿效应磁强计微机电系统