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协作分集技术AF模式下反馈延迟随机性分析

电子与信息学报 2011年第12期33卷 2978-2983页

作者：汪三骏黄生叶湖南大学信息科学与工程学院长沙410082

该文采用一个三节点协作分集放大中继网络为研究模型。在Nakagami-m衰落信道条件下,对源节点发送一帧数据的反馈延迟的随机性进行了研究。数据帧在三节点协作网络中可以通过直接链路和中继链路到达目的节点,在物理层源节点根据信道条件... 详细信息

该文采用一个三节点协作分集放大中继网络为研究模型。在Nakagami-m衰落信道条件下,对源节点发送一帧数据的反馈延迟的随机性进行了研究。数据帧在三节点协作网络中可以通过直接链路和中继链路到达目的节点,在物理层源节点根据信道条件不同,采用自适应调制编码技术,选择不同调制编码模式发送数据帧。结合以上原因,对数据帧的反馈延迟稳态分布进行研究。构造有限状态马尔科夫模型分析Nakagami-m信道的相关性,得到信道状态转移关系矩阵。推导出在研究模型中数据帧发送一次的反馈延迟的转移概率关系,经过仿真实验结果与数值分析结果的对比,验证了推导分析方法的准确性。最后分析信道衰落系数m和物理层最大误帧率Pm ax对于反馈延迟概率分布的影响。

关键词：无线通信协作分集自适应调制与编码有限状态马尔科夫模型反馈延迟转移概率

黄河中下游冲积平原深长桩桩侧极限摩阻力研究

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西安建筑科技大学学报（自然科学版） 2011年第4期43卷 507-512,575页

作者：董三升赵均海雷自学长安大学建筑工程学院陕西西安710061

对于黄河中下游冲积平原砂性土层深长桩桩侧极限摩阻力问题,根据该地区的地质特性、采用有限元软件ABAQUS对大量不同参数的深长桩进行了建模分析,结果表明:桩顶荷载与桩侧摩阻力近似呈线性关系,桩长、桩径、桩-土界面条件、桩周土的力... 详细信息

对于黄河中下游冲积平原砂性土层深长桩桩侧极限摩阻力问题,根据该地区的地质特性、采用有限元软件ABAQUS对大量不同参数的深长桩进行了建模分析,结果表明:桩顶荷载与桩侧摩阻力近似呈线性关系,桩长、桩径、桩-土界面条件、桩周土的力学性质等对桩侧摩阻力影响程度不同.根据有限元计算结果推导出了砂性土层深长桩桩侧极限摩阻力的计算公式,用其对工程实例进行验算,并将计算结果与静载试验实测结果进行了对比,二者吻合较好,说明有限元建模方法、参数设置及结论可靠,计算公式较准确.该研究可为该地区深长桩的优化设计提供参考.

关键词：深长桩极限摩阻力砂性土有限元

Influence of aging treatment on corrosion behavior and mechanism of Mg–Y alloys

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Journal of Central South University 2018年第5期25卷 987-1002页

作者：徐宏张新蒋三生任霁萍高翔宇 School of Materials Science and Engineering North University of China Institute of Thermal Power Generation Technology China Datang Corporation Science and Technology Research Institute State Key Lab for Fabrication & Processing of Non-ferrous Metals Beijing General Research Institute for Non-ferrous Metals School of Mechanical and Electronic Engineering Beijing Agricultural Vocation College Department of Automotive Engineering Tsinghua University

This paper studied the influence of aging treatment on the corrosion behavior and mechanism of Mg-Y alloys with different Y content through corrosion mass loss test, electrochemical test and corrosion morphologies observation. Results show that the peak-aging times of Mg-（0.25, 2.5, 5, 8 and 15） Y alloys at 250 ℃ were 4, 6, 10, 12 and 16 h. The aging treatment reduced the corrosion resistance of Mg-Y alloys, and the corrosion resistance of Mg-Y alloys became worse with increasing of the aging time. The change magnitude of the open circuit potentials for Mg-（0.25, 2.5）Y alloys was greater than that of Mg-（5, 8 and 15）-Y alloys. The polarization curves of Mg （0.25, 2.5, 5, 8 and 15） Y alloys had the similar shape after aging treatment, and the slopes of the anodic branch were greater than those of the cathodic branches. After aging treatment, the corrosion modes of Mg-0.25Y and Mg-（2.5, 5, 8 and 15） Y alloys were uniform corrosion and pitting corrosion with small local deep corrosion.

关键词： Mg-Y alloy aging treatment electrochemical corrosion resistance corrosion morphology

LiNbO_3电光调制器的小信号功率测试法研究

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光电子．激光 2006年第1期17卷 37-40页

作者：黄亨沛伞海生张家宝祝宁华中国科学院半导体研究所集成光电子学国家重点实验室北京100083

阐述了小信号功率测试法测量LiNbO3电光调制器频率响应的原理,对传统的小信号功率测试法加以改进,在以网络分析仪(VNA)为主的常用扫频测试系统基础上建立起一套简单可靠的新型测试系统,实现了计算机控制自动测量。改进的测试方法考虑了... 详细信息

阐述了小信号功率测试法测量LiNbO3电光调制器频率响应的原理,对传统的小信号功率测试法加以改进,在以网络分析仪(VNA)为主的常用扫频测试系统基础上建立起一套简单可靠的新型测试系统,实现了计算机控制自动测量。改进的测试方法考虑了测试系统中微波器件固有频响对测试结果的影响,并通过对器件进行校准加以消除。通过实验表明该方法的准确性。

关键词： LiNbO3电光调制器频率响应小信号功率测试

Effect of laser shock processing on fatigue life of fastener hole

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Transactions of Nonferrous Metals Society of China 2014年第4期24卷 969-974页

作者：张兴权陈六三余晓流左立生周煜安徽工业大学机械工程学院马鞍山243002

The fatigue properties of laser shock processing （LSP） on both side surfaces of fastener hole with diameter of 3 mm in the LY12CZ aluminum alloy specimens were investigated. The superficial residual stress was measured by X-ray diffraction method. Fatigue experiments of specimens with and without LSP were performed, and the microstructural features of fracture of specimens were characterized by scanning electron microscopy （SEM）. The results indicate that the compressive residual stress can be induced into the surface of specimen, and the fatigue life of the specimen with LSP is 3.5 times as long as that of specimen without LSP. The location of fatigue crack initiation is transferred from the top surface to the sub-surface after LSP, and the fatigue striation spacing of the treated specimen during the expanding fatigue crack is narrower than that of the untreated specimen. Furthermore, the diameters of the dimples on the fatigue crack rupture zone of the specimen with LSP are relatively bigger, which is related to the serious plastic deformation in the material with LSP.

关键词： laser shock processing fastener hole fatigue life LY12CZ

Acupuncture on back-shu points of five zang for chronic fatigue syndrome:A randomized control trial

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World Journal of Acupuncture-Moxibustion 2018年第4期28卷 237-241,309-310页

作者： san-san CHEN Ran LIU Bin WU sheng CHEN Fang GUO Xiao-lin XUE Jun WANG Acupuncture Department Dongzhimen HospitalBeijing University of Chinese MedicineBeijing 100700China Chinese Medicine Department People’s HospitalBeijing UniversityBeijing 100044China Beijing University of Chinese Medicine Beijing 100029China

Objective: To observe the clinical efficacy of acupuncture on back-shu points of five zang in treating chronic fatigue syndrome(CFS).Methods: Sixty patients were randomized into treatment group and control group. In treatment group,the back-shu points of five zang organs were adopted for acupuncture. Shènshū(肾俞 BL23) was perpendicularly needled 15-30 mm in depth. The rest of the selected points were inserted obliquely 15-30 mm in the direction of the spine with even method of lifting-thrusting and twisting-twirling, 10 s for each acupoint. In control group, the acupoints were approximately 1.5-2 cm away outward from the back-shu points of five zang organs(about on the middle of the two sidelines of the bladder meridian of foottaiyang) and the points from the bladder meridian of foot-taiyang were excluded. Acupoints were needled6-9 mm in depth, and deqi was not required, without any manipulation. The treatments were carried out twice a week for twenty minutes each time, a total of eight treatments were given. The clinical efficacy of acupuncture treatment for CFS was evaluated through the Fatigue Scale-14(FS-14) and the Symptom Check-List 90(SCL-90) after ***: The total effective rate was 86.67% in the treatment group and 53.33% in the control group(P<0.01). In treatment group, FS-14 total scores, somatic fatigue scores, and mental fatigue scores were significantly reduced than before treatment(all P<0.01). In control group, FS-14 total scores and somatic fatigue scores were significantly reduced(both P<0.01). The improvement of FS-14 total scores, somatic fatigue scores, and mental fatigue scores in the treatment group were better than those in the control group(P<0.01, P<0.05). After treatment, SCL-90 total scores and somatization, compulsion, interpersonal sensitivity, depression, anxiety, hostility, psychoticism, and other factors scores were significantly reduced in the treatment group compared with before treatment(P<0.01). In control group, the S

关键词： Chronic fatigue syndrome Back-shu points of five zang Acupuncture thrapy Randomized control trial

替加氟衍生物M1的合成及其体内外抗肿瘤活性研究

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中国药理学通报 2013年第1期29卷 145-146页

作者：秦三海刘爱芹于胜海王风玲山东省医学科学院药物研究所山东省罕少见病重点实验室山东济南250062

化疗是治疗癌症的重要手段之一，替加氟为常用的一线化疗药物，但其不良反应严重，如何使其在发挥抗肿瘤作用的同时，减少毒副作用成为众多学者关注的焦点。本研究以替加氟为母体，分子中引入1，3，4-噻二唑类杂环和酰氨基团，设计合成... 详细信息

化疗是治疗癌症的重要手段之一，替加氟为常用的一线化疗药物，但其不良反应严重，如何使其在发挥抗肿瘤作用的同时，减少毒副作用成为众多学者关注的焦点。本研究以替加氟为母体，分子中引入1，3，4-噻二唑类杂环和酰氨基团，设计合成新型化合物M1，使其抗肿瘤活性叠加，毒性降低，并对其体内外抗肿瘤活性进行了研究，以期为合成高效低毒的抗肿瘤药物提供实验依据。

关键词：替加氟衍生物化学合成 MTT 抗肿瘤毒性

Molecular cloning and characterization of three phenylalanine ammonia-lyase genes from Schisandra chinensis

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Chinese Journal of Natural Medicines 2022年第07期 527-536页

作者： FAN san-Peng CHEN Wei WEI Jiang-Chun GAO Xiao-Xu YANG Yong-Cheng WANG An-Hua HU Gao-sheng JIA Jing-Ming School of Traditional Chinese Materia Medica Shenyang Pharmaceutical University

Phenylalanine ammonia-lyase（PAL）, which catalyzes the conversion from L-phenylalanine to trans-cinnamic acid, is a well-known key enzyme and a connecting step between primary and secondary metabolisms in the phenylpropanoid biosynthetic pathway of plants and microbes. Schisandra chinensis, a woody vine plant belonging to the family of Magnoliaceae, is a rich source of dibenzocyclooctadiene lignans exhibiting potent activity. However, the functional role of PAL in the biosynthesis of lignan is relatively limited, compared with those in lignin and flavonoids biosynthesis. Therefore, it is essential to clone and characterize the PAL genes from this valuable medicinal plant. In this study, molecular cloning and characterization of three PAL genes（ScPAL1-3） from *** was carried out. ScPALs were cloned using RACE PCR. The sequence analysis of the three ScPALs was carried out to give basic characteristics followed by docking analysis. In order to determine their catalytic activity, recombinant protein was obtained by heterologous expression in pCold-TF vector in Escherichia coli（BL21-DE3）, followed by Ni-affinity purification. The catalytic product of the purified recombinant proteins was verified using RP-HPLC through comparing with standard compounds. The optimal temperature, pH value and effects of different metal ions were determined. Vmax, Kcatand Kmvalues were determined under the optimal conditions. The expression of three ScPALs in different tissues was also determined. Our work provided essential information for the function of ScPALs.

关键词：

Deficiency of mitochondrial aldehyde dehydrogenase increases type 2 diabetes risk in males via autophagy dysregulation

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Chinese Medical Journal 2021年第18期134卷 2246-2248页

作者： Xiang-Wei Liu Lin Jiang Peng Wang Xiao-Lei Sun Xin Ma Hong Zhu Zhen Dong Cheng Shen san-Li Qian Bing-Yu Li Zhen-sheng Xu Ai-Jun Sun Jun-Bo Ge Shanghai Institute of Cardiovascular Diseases Zhongshan HospitalFudan UniversityShanghai 200032China Xiangya Hospital Central South UniversityChangshaHunan 410008China Huashan Hospital Fudan UniversityShanghai 200040China Institute of Biomedical Science Fudan UniversityShanghai 200032China

Metrics To the editor:The diabetes epidemic has increasingly become a major public health concern *** 2014,there were 102.9 million diabetic adults in China,representing 24.4%of the world's diabetic population,even though China only comprised 18.7%of the global population at the time.[1]Furthermore,the estimated overall prevalence of diabetes and prediabetes was 10.9%and 35.7%,respectively,indicating China as one of the countries with the highest prevalence of diabetes in the world.[2]Although factors,including sedentary lifestyles and energy-dense diets,drive the diabetes epidemic,genetic architecture may also contribute to the susceptibility of an individual's response to environmental *** dehydrogenase(ALDH)2 is a key enzyme that eliminates toxic aldehydes by catalyzing their oxidation to non-reactive *** evidence has suggested that individuals with ALDH2 deficiency have an increased risk of cardiovascular and metabolic diseases,in addition to alcohol intolerance,nitroglycerin tolerance,and carcinoma.[3]Notably,a unique ALDH2 loss-of-function allele,ALDH2∗2,is found in approximately 50%of the East Asian and 8%of the global *** has been reported that this ALDH2 mutation is associated with a higher prevalence of diabetes in coronary artery disease(CAD)patients,accompanied with increased C-reactive protein(CRP)levels.[4]ALDH2 mutation is also related to various diabetes risk factors,but the direct correlation remains ***,we have explored the potential pathogenicity and mechanisms of ALDH2 deficiency in the development of type 2 diabetes in both laboratory and clinical settings.

关键词： diabetes prevalence eliminate