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Major reactive species of ambient volatile organic compounds (VOCs) and their sources in Beijing

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Science China Earth Sciences 2005年第Z2期48卷 147-154页

作者： SHAO min FU Linlin LIU Ying LU Sihua ZHANG Yuanhang tang Xiaoyan State Joint Key Laboratory of Environmental Simulation and Pollution Control College of Environmental SciencesPeking UniversityBeijing 100871China

Volatile organic compounds(VOCs)are important precursors of atmospheric chemical *** a whole mixture,the ambient VOCs show very strong chemical *** on OH radical loss rates in the air,the chemical reactivity of VOCs in Beijing was *** results revealed that alkenes,accounting for only about 15%in the mixing ratio of VOCs,provide nearly 75%of the reactivity of ambient VOCs and the C4 to C5 alkenes were the major reactive species among the *** study of emission characteristics of various VOCs sources indicated that these alkenes are mainly from vehicle exhaust and gasoline *** reduction of alkene species in these two sources will be effective in photochemical pollution control in Beijing.

关键词： alkenes radicals vehicle exhaust gasoline evaporation.

电离辐射致小鼠海马神经细胞凋亡及p53与PUMA表达改变

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毒理学杂志 2010年第5期24卷 359-362页

作者：韩颖颖陈玉均季斌汤乐民王海健韩毓姜声扬南通大学公共卫生学院江苏南通226000 南通大学附属医院放射治疗科

目的研究电离辐射对小鼠海马神经细胞凋亡及p53、p53 up-regulated modulator of apoptosis(PUMA)蛋白表达的变化。方法 60只ICR小鼠随机分为0.4、4、10和18 Gy 4个照射剂量组及对照组。处理后在4 h时间点取小鼠全脑,原位末端标记(TUNEL... 详细信息

目的研究电离辐射对小鼠海马神经细胞凋亡及p53、p53 up-regulated modulator of apoptosis(PUMA)蛋白表达的变化。方法 60只ICR小鼠随机分为0.4、4、10和18 Gy 4个照射剂量组及对照组。处理后在4 h时间点取小鼠全脑,原位末端标记(TUNEL)法检测海马神经细胞凋亡;蛋白免疫印迹(Western blot)法检测海马组织中p53与PUMA蛋白的表达情况。结果 TUNEL结果显示细胞凋亡率随照射剂量增加而增加;Western blot结果显示X射线照射后4 h点p53、PUMA表达随剂量增高而增加,二者的表达呈平行状态。结论在本试验条件下,电离辐射致小鼠海马神经细胞出现不同程度的凋亡并呈现剂量-效应关系;小鼠海马组织中p53和PUMA蛋白表达有明显的剂量依赖性,且和细胞凋亡的改变有一定关联。

关键词：电离辐射小鼠海马细胞凋亡 p53 PUMA

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范仲淹经学核心思想探析

中州学刊 2024年第9期 108-116页

作者：姜广辉唐陈鹏湖南大学岳麓书院湖南长沙410082

范仲淹是宋代士人中集经术、事功、道德、文章于一身的“第一人”。由于范仲淹的人品、事业在当时太过辉耀,导致其在经学上的建树被道德功名掩盖,故而长期不为学界所关注。近年来,学者们对范仲淹经学的研究已经有所推进,但大多是从易学... 详细信息

范仲淹是宋代士人中集经术、事功、道德、文章于一身的“第一人”。由于范仲淹的人品、事业在当时太过辉耀,导致其在经学上的建树被道德功名掩盖,故而长期不为学界所关注。近年来,学者们对范仲淹经学的研究已经有所推进,但大多是从易学、春秋学等单一经学学科对其经学思想进行探索与阐释。若从整体的层面对范仲淹的经学进行深入分析,则可发现其经学的核心思想主要包括以下几个方面的内容:一是“政必顺民”的民本思想,包括养民、利民、爱民等具体内容;二是“穷变通久”的改革思想,将《周易》“穷则变,变则通,通则久”的理论作为主导“庆历新政”的哲学思想;三是“先忧后乐”的忧乐思想,进则忧国忧民,退则乐天乐道。

关键词：范仲淹经学民本改革忧乐

Impact Fretting Wear Behavior of Alloy 690 Tubes in Dry and Deionized Water Conditions

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Chinese Journal of Mechanical Engineering 2017年第4期30卷 819-828页

作者： Zhen-Bing Cai Jin-Fang Peng Hao Qian Li-Chen tang min-Hao Zhu Traction Power State Laboratory Southwest Jiaotong University Chengdu 610031 China Shanghai Nuclear Engineering Research and Design Institute Shanghai 200233 China

The impact fretting wear has largely occurred at nuclear power device induced by the flow-induced vibra- tion, and it will take potential hazards to the service of the equipment. However, the present study focuses on the tangential fretting wear of alloy 690 tubes. Research on impact fretting wear of alloy 690 tubes is limited and the related research is imminent. Therefore, impact fretting wear behavior of alloy 690 tubes against 304 stainless steels is investigated. Deionized water is used to simulate the flow environment of the equipment, and the dry envi- ronment is used for comparison. Varied analytical tech- niques are employed to characterize the wear and tribochemical behavior during impact fretting wear. Char- acterization results indicate that cracks occur at high impact load in both water and dry equipment; however, the water as a medium can significantly delay the cracking time. The crack propagation behavior shows a jagged shape in the water, but crack extended disorderly in dry equip- ment because the water changed the stress distribution and retarded the friction heat during the wear process. The SEM and XPS analysis shows that the main failure mechanisms of the tube under impact fretting are fatiguewear and friction oxidation. The effect of medium（water） on fretting wear is revealed, which plays a potential and promising role in the service of nuclear power device and other flow equipments.

关键词： Impact fretting wear Alloy 690 Oxidativewear Crack Fracture appearance

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眼科学临床教学的新思路

实用预防医学 2004年第6期11卷 1295-1296页

作者：于惠敏唐仁泓陈国平中南大学湘雅三医院眼科湖南长沙410013

为了提高眼科学临床教学效果 ,通过对教学课时及内容的合理安排、优化教学多媒体、加强实践环节、培养学生自我挑战意识、启发和锻炼临床逻辑思维、及正视和处理反移情现象 ,总结出眼科学临床教学应建立的教学新思路 -加强实践 ,重视临... 详细信息

为了提高眼科学临床教学效果 ,通过对教学课时及内容的合理安排、优化教学多媒体、加强实践环节、培养学生自我挑战意识、启发和锻炼临床逻辑思维、及正视和处理反移情现象 ,总结出眼科学临床教学应建立的教学新思路 -加强实践 ,重视临床思维启发和培养 ,防范反移情促进师生之间的互动情感。

关键词：眼科学实践自我挑战反移情

借用动态仿真演示辅助分析复杂电力信号回路的应用

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电工技术 2019年第20期 140-141,143页

作者：龙真生李琰唐敏覃健翔农红丽段梦静广西大学行健文理学院

为了让学生能快速、直观地掌握复杂的电气工作原理,文章借用动态仿真演示辅助分析复杂电力信号回路,并详细阐述了分析过程。

关键词：中央信号动态仿真工作原理

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猕猴大脑中动脉中膜平滑肌的定量分析

新乡医学院学报 1994年第4期11卷 333-35页

作者：张红旗唐建民冯艳玲大庆职工医学院

目的为探讨脑血管病伴随增龄而去生的原因，我们研究了猕猴大脑中动脉中膜平滑肌细胞与间质的增龄变化。方法9只健康雄性猕猴，麻醉后开胸，以37℃生理盐水冲洗心脏和血管，再在生理压下灌注固定，取出大脑中动脉，按TEM常规处理标本，H... 详细信息

目的为探讨脑血管病伴随增龄而去生的原因，我们研究了猕猴大脑中动脉中膜平滑肌细胞与间质的增龄变化。方法9只健康雄性猕猴，麻醉后开胸，以37℃生理盐水冲洗心脏和血管，再在生理压下灌注固定，取出大脑中动脉，按TEM常规处理标本，H—600电镜观察，用Walmsley等的方法对中膜平滑肌进行定量分析。结果大脑中动脉的增龄变化以中膜平滑肌细胞和间质变化最明显、幼年组、成年组与老年组中膜平滑肌细胞占中膜面积的百分比分别是71.8％、64.8％与63.1％，三组均数差异具有显著性（P＜0.01）。结论随着增龄中膜平滑肌占中膜面积的百分比逐渐下降，间质逐渐增多。此种定量方法能客观的反映平滑肌细胞和间质的变化。

关键词：解剖学猴脑动脉平滑肌定量分析

mining item-item and between-set correlated association rules

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第2期12卷 96-109页

作者： Bin SHEN min YAO Li-jun XIE Rong ZHU Yun-ting tang Ningbo Institute of Technology Zhejiang University Ningbo 315100 China School of Computer Science and Technology Zhejiang University Hangzhou 310027 China Center for Engineering & Scientific Computation School of Aeronautics and Astronautics Zhejiang University Hangzhou 310027 China

To overcome the failure in eliminating suspicious patterns or association rules existing in traditional association rules mining, we propose a novel method to mine item-item and between-set correlated association rules. First, we present three measurements: the association, correlation, and item-set correlation measurements. In the association measurement, the all-confidence measure is used to filter suspicious cross-support patterns, while the all-item-confidence measure is applied in the correlation measurement to eliminate spurious association rules that contain negatively correlated items. Then, we define the item-set correlation measurement and show its corresponding properties. By using this measurement, spurious association rules in which the antecedent and consequent item-sets are negatively correlated can be eliminated. Finally, we propose item-item and between-set correlated association rules and two mining algorithms, I&ISComine_AP and I&ISComine_CT. Experimental results with synthetic and real retail datasets show that the proposed method is effective and valid.

关键词： Item-item and between-set correlated association rules All-confidence All-item-confidence Item-set correlation mining algorithms Pruning effect

microRNAs, an active and versatile group in cancers

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International Journal of Oral Science 2011年第4期3卷 165-175页

作者： Jeffrey Liu min Zheng Ya-ling tang Xin-hua Liang Qin Yang Department of Biological Sciences University of Delaware Nowak DE 19716 USA State Key Laboratory of Oral Diseases Sichuan University Chengdu 610041 China Department of Oral and Maxillofacial Surgery West China School of Stomatology Sichuan University Chengdu 610041 China Cancer Biology Division School of Medicine Washington University St. Louis MO 63108 USA

microRNAs （miRNAs） are a class of non-coding RNAs that function as endogenous triggers of the RNA interference pathway. Studies have shown that thousands of human protein-coding genes are regulated by miRNAs, indicating that miRNAs are master regulators of many important biological processes, such as cancer development, miRNAs frequently have deregulated expression in many types of human cancers, and play critical roles in tumorigenesis, which functions either as tumor suppressors or as oncogenes. Recent studies have shown that miRNAs are highly related with cancer progression, including initiating, growth, apoptosis, invasion, and metastasis. Furthermore, miRNAs are shown to be responsible for the cancer-related inflam- mation, anti-cancer drug resistance, and regulation of cancer stem ceils. Therefore, miRNAs have generated great interest as a novel strategy in cancer diagnosis and therapy. Here we review the versatile roles of miRNAs in cancers and their potential applications for diagnosis, prognosis, and treatment as biomarkers.

关键词： microRNAs cancer epithelial-mesenchymal transition inflammation cancer stem cells drug resistance