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Relationship between osteocyte apoptosis and orbital bone development in rabbits

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山西医科大学学报 2004年第6期35卷 535-537,558页

作者： majian-min LIZhi-hui OphthahnologicResearchCenter ChineseAcademyofMedicalSciencesDeptofOphathahnologyPekingUnionMedicalCollegeHospitalBeijing100733China DeptofOphathalmology BeijingTongrenHospitalCapitalUniversityofMedicalSciencesBeijingChina

Objective To investigate whether the osteocyte apoptosis exists in orbital bones and to discuss its effect on the orbital development. Methods Seven young Newzealand white rabbits were selected as experimental *** two-month-old ,all rabbits were killed and then zygomas were made into paraffin and electron microscope sections after they were decalcified. Apoptosis of osteocytes was observed by light microscope and transmission electron microscopes and detected by TUNEL staining. Results The classical apoptosis of osteocytes was found under light and transmission electron microscopes. Apoptosis of osteocytes was diffused irregularly in the zygomatic tissue. Conclusion Osteocyte can apoptosis and it may participate in the development of the bony orbit.

关键词：骨细胞动物实验电镜染色

Speciation of Black-necked Crane

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Journal of Northeast Agricultural University(English Edition) 2002年第2期9卷 111-116页

作者： BAIXiu－juan majian－zhang JilingricultureUniversity Changchun130118PRC NortheastForestryUniversity HarbinHeilongjiang150040PRC

Based on the concepts of species and speciation,the speciation of Black necked Grane(Grus nigricollis) was discussed using bio geographic principles and some evidences suggest that Black necked Grane had a close relationship with Red crowned Crane(Grus japonensis).The Qinghai Tibetan Plateau uplift may be the most important factor in allopatric speciation for Black necked Crane.

关键词： Black necked Crane speciation qinghai tibetan plateau

Metastatic tumor to the iris and ciliary body as an initial sign of lung cancer: a case report

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Chinese Medical Journal 2005年第13期118卷 1131-1133页

作者： SUIRui-fang ZHAOJia-liang ZHANGShun-hua FENGRui-e CHENGGang-wei majian-min MAOJin DepartmentofOphthalmologyPekingUnionMedicalCollegeHospital ChineseAcademyofMedicalSciencesBeijing100730China DepartmentofPathologyPekingUnionMedicalCollegeHospital ChineseAcademyofMedicalSciencesBeijing100730China

The most common sites of lung cancer metastases are pleura, bone, brain,pericardium and liver. Tumor metastasis to the eye is a rare complication of lung cancer. Metastaticcancer to the ocular region most often involves the uveal tract, however, most uveal metastasesoccur in the posterior uvea, and iris metastases are relatively rare. We describe a patient withadenocarcinoma of the lung metastatic to the iris as the first clinical sign without symptoms oflung cancer.

关键词： metastatic tumor iris lung cancer

Determination of ultimate bearing capacity of uplift piles using intact and non-intact load−displacement curve

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Journal of Central South University 2022年第2期29卷 470-485页

作者： WANG Qin-ke majian-lin JI Yu-kun ZHANG Jian CHEN Wen-long School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China School of Chemistry University of NottinghamNottingham NG72RDUnited Kingdom State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou 221116China

Based on the field destructive test of six rock-socketed piles with shallow overburden,three prediction models are used to quantitatively analyze and predict the intact load−displacement *** predicted values of ultimate uplift capacity were further determined by four methods(displacement controlling method(DCM),reduction coefficient method(RCM),maximum curvature method(MCM),and critical stiffness method(CSM))and compared with the measured *** the analysis of the relationship between the change rate of pullout stiffness and displacement,a method used to determine the ultimate uplift capacity via non-intact load−displacement curve was *** results show that the predicted value determined by DCM is more conservative,while the predicted value determined by MCM is larger than the measured *** suggests that RCM and CSM in engineering applications can be preferentially ***,the development law of the change rate of pullout stiffness with displacement agrees well with the attenuation form of power *** theoretical predicted results of ultimate uplift capacity based on the change rate of pullout stiffness will not be affected by the integrity of the *** method is simple and applicable for the piles that are not loaded to failure state,and thus provides new insights into ultimate uplift capacity determination of test piles.

关键词： load−displacement curve prediction model determination method of bearing capacity change rate of pullout stiffness

信息资源质量评价框架下价值感知的作用机理实证研究

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现代情报 2017年第7期37卷 20-24页

作者：王剑高峰马健中国农业科学院农业信息研究所北京100081 天津社会科学院经济社会预测研究所天津300191

在信息资源利用过程中,用户的质量评价行为和价值感知行为一直是学术界关注的重点内容。在借鉴前期研究成果的基础上,通过调查问卷所搜集的数据,实证分析了在信息资源利用情境下,用户价值感知行为和质量评价判定的关联关系及其作用机理... 详细信息

在信息资源利用过程中,用户的质量评价行为和价值感知行为一直是学术界关注的重点内容。在借鉴前期研究成果的基础上,通过调查问卷所搜集的数据,实证分析了在信息资源利用情境下,用户价值感知行为和质量评价判定的关联关系及其作用机理。相关研究结果表明,用户在信息资源利用中,价值感知行为对质量评价的中介效应显著,能够直接地影响质量评价的效果,且二者之间在功能上有着显著的关联。并以此结论为基础为未来信息资源服务的相关研究提出了建议,以期能够为其他类似的研究提供理论支撑和启示。

关键词：信息资源质量评价价值感知作用机理实证研究

Restriction endonucleases digesting DNA in PCR buffer

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Journal of Forestry Research 2005年第1期16卷 58-60,i003-i004页

作者： LIUXue-dong ZHENGDong ZHOUYan-na MAOWei-wei majian-zhang CollegeofWildlifeResources NortheastForestryUniversity26HexingRoadHarbin150040P.RChina CollegeofLifeScience NortheastForestryUniversity26HexingRoadHarbin150040P.R.China CollegeofWildlifeResources NortheastForestryUniversity26HexingRoadHarbin150040P.RChina

Six commonly used restriction endonucleases (REs) (Acc I, Ban II, EcoR I, Hind III, Sac I, Sca I) were tested for their ability to directly digest DNA completely in the Polymerase Chain Reaction (PCR) buffers. The results showed that: with the requirement for addi- tional magnesium supplemented as activator, REs, except EcoR I appeared star activity, completely digested unmethylated lambda DNA af- ter overnight incubation in PCR buffer and functioned as equally well as in recommended Restriction Enzyme Buffer provided with each enzyme; all REs tested completely digested PCR products in PCR buffer, it implied digestion of PCR products may often be performed di- rectly in the PCR tube without the requirement for any precipitation or purification steps; and the concentration of MgCl2 from 2.5 mmol·L-1 to 10 mmol·L-1 did not significantly affect activity of REs in PCR buffer. This simplified method for RE digestion of PCR prod- ucts could have applications in restriction fragment length polymorphism (RFLP) analysis and single-stranded conformational polymor- phism (SSCP) analysis of large PCR products. However, usage of this procedure for cloning applications needs further data.

关键词： Restriction endonucleases: Digestion: PCR Buffer

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考虑行人保护策略的交叉口信号配时优化模型

交通运输系统工程与信息 2021年第3期21卷 71-77,85页

作者：杨震马健霄王宝杰李根南京林业大学汽车与交通工程学院南京210037 长安大学运输工程学院西安710064

为促进平面交叉口的行人交通安全,本文基于美国国家电气制造商协会(NEMA)的双环相位标准,将行人专用相位(EPP)、行人同步保护相位(CYPP)以及行人前置相位(LPI)这3种行人保护策略整合到一起,以信号周期和行人-右转车的冲突点数量最小化... 详细信息

为促进平面交叉口的行人交通安全,本文基于美国国家电气制造商协会(NEMA)的双环相位标准,将行人专用相位(EPP)、行人同步保护相位(CYPP)以及行人前置相位(LPI)这3种行人保护策略整合到一起,以信号周期和行人-右转车的冲突点数量最小化为目标,构建交叉口信号配时优化模型。在假定交通参与者遵守信号规则的前提下,除LPI策略中远端行人与右转车冲突外,其余冲突点经模型优化后皆可消除,并且机动车的通行效率能够得到维持。该模型属于0-1混合整数线性规划问题(BMILP),可用分支定界法求解。选取南京市两个交叉口进行实例研究。结果表明:在交叉口几何尺寸及交通流量较小时,模型倾向于得到EPP方案,否则倾向于得到CYPP和LPI方案;在进口道设有直右共享车道或右转相位不易满足最大饱和度限制时,模型倾向于得到LPI方案。

关键词：交通工程信号配时优化 0-1混合整数线性规划交叉口行人保护策略

基于多准则分区和WLS-PDIPM算法的有源配电网状态估计

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电力系统自动化 2016年第12期40卷 28-36页

作者：马健唐巍徐升张璐刘科研杨德昌中国农业大学信息与电气工程学院北京市100083 中国电力科学研究院北京市100192

针对复杂有源配电网三相不平衡状态估计计算速度较慢与计算精度较低的问题,提出了一种基于多准则分区和基本加权最小二乘法—原对偶内点法(WLS-PDIPM)混合算法的状态估计方法。基于对有源配电网中实时量测、虚拟量测和伪量测的配置分析... 详细信息

针对复杂有源配电网三相不平衡状态估计计算速度较慢与计算精度较低的问题,提出了一种基于多准则分区和基本加权最小二乘法—原对偶内点法(WLS-PDIPM)混合算法的状态估计方法。基于对有源配电网中实时量测、虚拟量测和伪量测的配置分析,建立了适用于复杂有源配电网状态估计的多准则分区优化模型,该模型综合考虑了分区后各子区域规模均衡、量测冗余度均衡及伪量测平均误差均衡。通过高级量测体系(AMI)全量测点实现各子区域完全解耦,有效减小了系统规模和雅可比矩阵阶数。所提方法将WLS与PDIPM的优点相结合,在提高算法精度的同时减少了计算时间。仿真算例结果表明所提方法可实现对复杂有源配电网的合理分区,有效提高了状态估计的计算速度与求解精度。

关键词：有源配电网状态估计多准则分区 WLS-PDIPM混合算法三相不平衡

非连续级配再生粗骨料自密实混凝土的工作性能试验研究

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混凝土 2014年第10期 109-113页

作者：吴春杨马剑潘志宏江苏科技大学土木工程与建筑学院江苏镇江212000

为了研究非连续级配再生粗骨料自密实混凝土的工作性能,采用控制变量法,研究了再生粗骨料取代率、砂率和经时损失对其工作性能的影响。试验结果表明:非连续级配的再生粗骨料可以配制出满足工作性能要求的自密实混凝土。当再生粗骨料取... 详细信息

为了研究非连续级配再生粗骨料自密实混凝土的工作性能,采用控制变量法,研究了再生粗骨料取代率、砂率和经时损失对其工作性能的影响。试验结果表明:非连续级配的再生粗骨料可以配制出满足工作性能要求的自密实混凝土。当再生粗骨料取代率为50%时工作性能最好;当砂率为45%时,新拌混凝土的工作性能最好;随着时间的延长,新拌混凝土工作性能下降,添加适量的聚羧酸高性能减水剂可以恢复其坍落扩展度;给出的坍落扩展度经时损失公式计算简单,计算结果准确,可以作为新拌混凝土经时损失评价的参考。

关键词：自密实混凝土再生混凝土工作性能非连续级配骨料