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Reverse Peeling of Brittle Coating Overlaying on Ductile Substrate

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Reverse Peeling of Brittle Coating Overlaying on Ductile Sub...

Developmental expression of Cyclin H and Cdk7 in zebrafish: the essential role of Cyclin H during early embryo development

Fifth International Conference on Surface Engineering

作者： K.Zhang1 C.W.Wu1 2.Q.Peng1 2.K.Zhang1 2.H.X.Li1 2.B.Q.Yang1 2.Y.Hu1 2.G.N.Chen1 1 Materials Processing Center Institute of Mechanics chinese Academy of sciences {2.100080 china 2.graduate School of the chinese Academy of sciences {2. 100080 china

It is widely known that the characterization of interfacial adhesion of coatings（films） is a great challenge for the researchers due to the unclearness of the loading and material conditions of interface cracking and coating *** brittle coating overlaying ductile substrate,multiple cracking occurs normally during global loading conditions such as tensile strain or bending *** this case,the complexity of interface stress leads to the difficulty to evaluate interfacial *** order to overcome this problem,a special testing method named as "reverse peeling" is proposed in this *** is based on our previous work on cross-sectional indentation and further interface mechanics analysis,and its principle can be described as the suppression of segmentation of the brittle coating and the promotion of deformation of the ductile *** in-house experimental set is established to test several plasma sprayed coatings which are prepared by different *** defined conditions including specimen size and loading parameter,coating cracks localized rather than sparsely,which is followed by interface *** adjusting loading condition,coating can be induced to peel from the underlying ***,through analyzing the chemical elements and microstructure of naked substrate surface and coating strip by SEM with EDS,coating spalling is affirmed to occur in "real" ***,due to the difference in the adhesion level of specimens used in this paper,different cracking behaviors can be observed for weak interface and relatively strong *** on experimental results,a simple spalling model considering the deformation mismatch between coating and substrate is *** FEM software ANSYS,stress of the interface can be *** has shown that interfacial normal stress plays a dominant role on the coating spalling,and it can be used to evaluate interfacial strength.

关键词： Coating Interfacial Adhesion Reverse Peeling FEM

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Cell Research 2007年第2期17卷 163-173页

作者： Qing Yun Liu~1 Zhi Li Wu~1 Wen Jian Lv~1 Yuan Chang Yan~(1,2. Yi Ping Li~1 ~1Lab of Molecular Cell Biology,Institute of Biochemistry and Cell Biology,Shanghai Institutes for Biological Science,chinese Academy of sciences,{2. School of the chinese Academy of sciences,3.0} Yue Yang Road,Shanghai 2.003.,china ~2.odel Organism Division,E-institutes of Shanghai University,Shanghai 2.002.,china LabofMolecularCellBiology InstituteofBiochemistryandCellBiologyShanghaiInstitutesforBiologicalScienceChineseAcademyofSciencesGraduateSchooloftheChineseAcademyofSciences320YueYangRoadShanghai200031China

Cyclin-dependent kinase 7(Cdk7)is the catalytic subunit of the metazoan Cdk-activating kinase(CAK).Activationof Cdk7 requires its association with a regulatory subunit,Cyclin *** the Cdk7/Cyclin H complex has beenimplicated in the regulation of RNA polymerase in several species,the precise function of their orthologs in zebrafish hasnot been fully *** this study,we isolated from zebrafish blastula embryos two cDNAs encoding the orthologsof human Cyclin H and Cdk7,and examined the role of Cdk7/Cvclin H in zebrafish *** analysisshowed that the zebrafish Cyclin H and Cdk7 cDNAs encode proteins with 65% and 86% identity to the respective hu-man ***-PCR and whole-mount in situ hybridization analyses of their expression in unfertilized eggs,embryosand organs of adult fish suggested that Cyclin H and Cdk7 messages are maternally *** data also showed thattheir transcripts were detected throughout *** of Cyclin H transcripts was found to be ubiquitousduring early stages of development and become restricted to the anterior neural tube,brain,eyes,procreate tissues,liverand heart by 5 days *** of a dominant-negative form of Cyclin H delayed the onset of zygotictranscription in the early embryo,resulting in apoptosis at 5 hours post-fertilization and leading to sever defects in tis-sues normally exhibiting high levels of Cyclin H *** results implicate Cyclin H in the regulation of thetranscriptional machinery during midblastula transition and suggest that it is an essential gene in early zebrafish larvaldevelopment.

关键词： Zebrafish Cyclin H Cdk7 whole-mount in situ hybridization embryonic development midblasmla transition

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数字钻孔摄像与钻孔CT层析成像测试试验

土木工程学报 2009年第8期42卷 104-108页

作者：孙卫春王川婴闵弘国家核电技术公司国核电力规划设计研究院北京100094 中国科学院武汉岩土力学研究所湖北武汉430071

数字钻孔摄像从侧视视角对整个钻孔的3.0°孔壁进行连续摄像,通过图像特征对孔内地质现象进行定性描述和定量分析,具有高分辨率、高井壁覆盖率和直观可信等特征;而钻孔CT层析成像利用弹性波波场特性,获得声波在不同介质中传播速率,从而... 详细信息

数字钻孔摄像从侧视视角对整个钻孔的3.0°孔壁进行连续摄像,通过图像特征对孔内地质现象进行定性描述和定量分析,具有高分辨率、高井壁覆盖率和直观可信等特征;而钻孔CT层析成像利用弹性波波场特性,获得声波在不同介质中传播速率,从而反映井间地质体的几何形态和物理特征。将这两种勘测手段联合能够发挥很好的互补性作用。数字钻孔摄像能够提供直观精确的孔壁全景图像,为钻孔CT层析成像测试结果提供佐证;而钻孔CT可延伸钻孔摄像的二维信息,对地质构造在钻孔间的发育情况进行三维空间上的分析。提出这样一种联合测探手段,并在一定向钻工程勘测中对其可行性进行试验,从而为进一步地质空间模型的建立提供实际支持。

关键词：数字钻孔摄像孔壁全景图像钻孔CT层析成像地质体测试试验

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N-cadherin is required for the maintenance of activity-dependent dendritic outgrowth

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N-cadherin is required for the maintenance of activity-depen...

The Antimutagenic and Anticarcinogenic Effects of Tea, Garllc and Other Natural Foods in china: A Review

中国神经科学学会第四次会员代表大会暨第八届全国学术会议

作者： Yun PENG~(1,2.,Zhu-Jun TAN~(1,2.,He-Ling SONG~1,Xiang YU~(1,*) 1 Institute of Neuroscience and State Key Laboratory of Neuroscience,Shanghai Institutes for Biological sciences, {3. Academy of sciences,Shanghai 2.003.,china 2.graduate School of the {3. Academy of sciences,Shanghai 2.003.,china

＜正＞Several lines of evidence show that neuronal activity can promote dendritic morphogenesis in vitro and in vivo. For example,light stimulation of tadpole tectal neurons promotes dendritic outgrowth,while enriched environment rearing of mammals can enhance the dendritic complexity of cortical pyramidal ***,the cytoskeletal and cell adhesion mechanisms through which neural activity mediates its effects remain to be *** previous work,we showed,in dissociated cultures of hippocampal neurons,that over-expression of the cell adhesion molecule N-cadherin promotes dendritic outgrowth while sequestering it blocks the effects of neural activity on promoting dendritic outgrowth. Here we show that mimicking increased neuronal activity by treating cultured hippocampal neurons for four hours with elevated extracellular potassium（KC1） can promote dendritic outgrowth,an effect which lasts 2. hours after KC1 was washed *** long lasting maintenance of nascent dendrites is dependent on N-cadherin-mediated trans-neuronal interactions,as disruption of this interaction with purified EC1 protein（the first extracellular domain of N-cadherin） or Ncad-Fc（extracellular domain of N-cadherin fused to Fc） blocks the effects of increased neural activity on increasing total dendritic branch number（TDBTN）.In addition,in neurons with reduced endogenous N-cadherin levels through expression of N-cadherin RNAi,the effects of increased activity on promoting dendritic outgrowth cannot be maintained. Consistent with these results,we found that neural activity can upregulate surface N-cadherin expression,an effect also dependent on N-cadherin-mediated trans-neuronal interactions,as it can be blocked by addition of purified EC1 or Ncad-Fc. Together,these results suggest that neural activity regulates the maintenance of nascent dendritic arbors through increasing the surface expression of N-cadherin,and furthermore,N-cadherin-mediated trans-neuronal interactions are required for ma

关键词： N-cadherin neuronal activity dendritic outgrowth maintenance initiation

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Biomedical and Environmental sciences 1992年第1期5卷 1-17页

作者： CHEN JUNSHIInstitute of Nutrition and Food Hygiene, chinese Academy of Preventive Medicine, 2. Nan WeiRoad, beijing 100050,{2. Institute of Nutrition and Food Hygiene Chinese Academy of Preventive Medicine Beijing.

It is well known that there are huge geographic variations in cancer rates in china's Mainland. For example, The National Cancer Control Office of the Ministry of Public Health (1979) reported that in the 1970s, cancer mortality rates for most cancers were found to be more than 2.-fold greater in some counties in others (Table 1). Esophageal cancer rates for males are a few hundred fold greater in the highest county when compared with the lowest county. The mortality rate for all cancers combined for males is 2. fold greater in the county with the highest mortality than in the county with the lowest *** to Doll and Peto (1981), about one third of human cancer death is avoidable by appropriate modification of the diet. Therefore, diet is very likely to have an important part in causing these huge geographic variations. The possible role of various mutagens and carcinogens (e.g. afiatoxin, N-nitroso compounds) in locally produced and consumed foods has been strongly suggested and widely acknowledged, although much more evidence would be required to confirm their actual functions in human cancer. On the other hand, there are a few reports stating that the human diet also contains powerful antimutagens and anticarcinogens (Ames, 1983.. The possible role of these two types of substances in causing the huge geographic variation of cancer risks remains elusive and inadequately explored. In order to make better use of these natural anticarcinogens in cancer prevention, it is important to elucidate their effects and mechanisms. The purpose of this paper is to summarize the available information on the antimutagenic and anticarcinogenic effects of natural foods in the {3. diet, excluding the effects of essential nutrients, e.g. dietary fibers, vitamins and minerals. Most of the literature cited in this review was published by {3. scientists.

关键词： The Antimutagenic and Anticarcinogenic Effects of Tea A Review Garllc and Other Natural Foods in china

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Effect of active immunization with peptides corresponding to the second extracellular loop of alpha1-adrenoceptor on vascular function in rats

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Effect of active immunization with peptides corresponding to...

Genetic relationship between parasitized and non-parasitized Haloxylon ammodendron in the Alxa Desert

中国生理学会第2.届全国会员代表大会暨生理学学术大会

作者： Li YAN~1,Zhong-Hua DAI~1,Guang-Zhao YANG~2.Su-Li ZHANG~2.Hui-Rong LIU~(2.3.,Ji-Min CAO~1 1 Department of Physiology and Pathophysiology,Institute of Basic Medical {3.,chinese Academy of Medical {3.,School of Basic Medicine,Peking Union Medical College,beijing 100005,china 2.Department of Physiology,Shanxi Medical University, Taiyuan,Shanxi,china 3.Department of Pathophysiology,School of Basic Medical {3.,Capital Medical University,beijing, 100069,china

Backgroud:Autoantibody against the second extracellular loop ofα-adrenoceptor(α-AA) which had been found in hypertensive patients possess agonist-like activity as phenylephrine evidenced by previous studies, however,long-term stimulation ofα-AA did not modify the mean arterial pressure in spite of the occurrence of cardiac and vascular remodeling,and the mechanism was not fully ***:In this study,the effect of acuteα-AA administration on mean arterial blood pressure was observed;the models with antibodies against theα-adrenoceptor were established by immunizing Wistar rats with the synthesized peptide corresponding to the second extracellular loop ofα-adrenoceptor(α-AR-EC).The age-matched male Wistar rats received a mixture of saline and immunological adjuvant as sham immunized *** the rats were raised for 8 *** blood pressure and heart rate were measured every *** reactivity experiments were performed in segments of thoracic ***-1(ET-1) concentration and iNOS expression were determined by ELISA and immunochemistry ***:The mean arterial pressure significantly increased after the administration ofα- AA in *** the systolic blood pressure of immunized rats having no difference with sham group,the isolated thoracic arteries showed hyperresponsiveness to phenylephrine and decreased endothelium-dependent relaxation at 6 and 8 months after initial ***,the plasma endothelin-1(ET-1) concentration and iNOS expression in vascular endothelium from the thoracic aorta increased,indicating that the long-term stimulation might contribute to endothelium injury,which plays an important role in the vasomotor dysfunction and enhanced pressor ***:The results demonstrated thatα-AA could contribute to vasomotor dysfunction in rats by vascular endothelial damage and increase iNOS expression,and might play a particular role in the pathological changes of hypertension.

关键词： receptor,adrenergic,alpha1 autoantibody vascular dysfunction hypertension

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Journal of Systematics and Evolution 2009年第3期47卷 255-262页

作者： 1,2.3.u-Mei WANG 1Dong-Ye YANG 4Yong-Zhen TIAN 5Peng-Fei TU 2.i-Shi SUN 1Xiao-Bo LI 1(School of Pharmacy, Shanghai Jiao Tong University, Shanghai 2.02.0, china) 2.College of Traditional chinese Materia Medica, Shenyang Pharmaceutical University, Shenyang 110016, china) 3.School of Medicine, Xi’an Jiaotong University, Xi’an 710061, china) 4(Forest and Desert Control Research Institute of Alxa League, Alxa League 7503.6, china) 5(Modern Research Center of Traditional chinese Medicine, School of Pharmaceutical sciences, Peking University, beijing 100083. china) (Modern Research Center of Traditional chinese Medicine School of Pharmaceutical Sciences Peking University Beijing 100083 China)

Haloxylon ammodendron (C. A. Mey.) Bunge is a host for the holoparasitic plant Cistanche deserticola Y. C. Ma, the original source of medicinal material known as Herba Cistanchis. The inter-simple sequence repeat marker was used to assess the genetic variations and relationships among six accessions of H. ammodendron with a total of 12. individuals collected from three localities in the Alxa Desert, Inner Mongolia, china. At each locality, individuals both parasitized (PP) by C. deserticola and non-parasitized (NP) were sampled. The results showed that Nei’s gene diversity and Shannon’s index of PP accessions were higher, but were not significantly different, from those of NP accessions. An unweighted pair-group method arithmetic average dendrogram showed two clusters, one that included all PP accessions, and the other the NP accessions. Genetic differentiation therefore existed between PP and NP accessions, which might be attributed to low gene flow between the NP and PP groups (Nm<1). However, the relationship between genetic distance and geographic distance within each group, although not statistically significant in this study, might be associated with high gene flow in both the NP and PP groups.

关键词： genetic relationship Haloxylon ammodendron ISSR marker parasitism.

Study on soil erosion dynamics in typical regionof southern china based on remote sensing, GISand gray forecast model

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Journal of Geographical sciences 1999年第4期9卷 387-393页

作者： ZHANG Jia-hua YAO Feng-met Chang-yao(START, InstitUte of Atmospheric Physics, chinese Academy of sciences, {2. 10002.)({2. Forestry University, Beliing 100083.(InstitUte of Remote Sensing Application, chinese Academy of sciences, {2. 100101, china)

This paper StUdies soil erosion dynamics in the typical region of southem china based onremote sensing, GIS tecndques and gray forecast model. The resultS of survey on Xingguo countyshown the soil eroded area and annual soil erosion amount decreased by 19.09% and 43.05%reSPectively from 1958 to 1988. The results of gray forecast model presented that soil eroded areaincreased from 818.04 km2.in 1988 to 12.6.69 km2.in 1995. in the meanthne the total soil erosiollamount decreased from 607.2.×104 ba in 1988 to 472. 12.×104 t/a in 1995. By comparing differentlanduse types, the soil loss modulus of the forest was the lowest with 177. 16~187.75t/km2. a, on thecontraly the bare land was the highest with 1062..76~112.5.48 t/km2. a. so the high vegetationcoverage can decrease soil and water loss effectively.

关键词： soil erosion dynamics. remote sensing. GIS gray forecast model, southern china

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基于对象方法的南岭山区雨雪冰冻灾害遥感检测与空间分析

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山地学报 2010年第4期28卷 478-486页

作者：朱俊凤钱峻屏廖广社王芳何克军张运英中国科学院广州地球化学研究所广州地理研究所广东省遥感与GIS应用重点实验室中国科学院研究生院广东省林业局广州大学

针对2.08年初的南方雨雪冰冻灾害,以受灾严重的广东南岭山区为研究区域,采用面向对象的方法进行森林植被破坏遥感检测研究,首先得到林地分布图,然后用K均值聚类法进行基于对象NDVI差值的森林受灾程度分级,得到灾害等级地图,最后用分带... 详细信息

针对2.08年初的南方雨雪冰冻灾害,以受灾严重的广东南岭山区为研究区域,采用面向对象的方法进行森林植被破坏遥感检测研究,首先得到林地分布图,然后用K均值聚类法进行基于对象NDVI差值的森林受灾程度分级,得到灾害等级地图,最后用分带统计法对灾害的空间分布形态进行了分析。林地提取的总体精度为95.3.%,灾害分级的总体精度为87.2.%,Kappa系数为80.74%。灾害空间分析表明:高程上,600～1600m主要为重度、中度受灾;600～13.0m,高程越高,受灾比例越大;13.0～1600m,比例有所下降;400m以下和1600m以上主要为轻度受灾;坡度上,随着坡度的增大,重度、中度受灾比例有所增加,但差异并不十分明显;坡向上,各级灾害比例几乎没有差别。

关键词：雨雪冰冻南岭面向对象遥感归一化植被指数(NDVI) 空间分析