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核电厂数字化人—机界面中信息显示的人因化设计 被引量:1
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作者 李鹏程 赵帅 《南华大学学报(社会科学版)》 2024年第1期7-13,共7页
为了提高核电厂数字化人—机界面中的信息显示设计水平和人员绩效,文章首先介绍了人因化设计的过程。然后从数字化主控室操纵员的认知和操作特性中找到了人因化设计的一般原理,包括:满足认知和操作需求的信息显示设计;满足任务绩效的信... 为了提高核电厂数字化人—机界面中的信息显示设计水平和人员绩效,文章首先介绍了人因化设计的过程。然后从数字化主控室操纵员的认知和操作特性中找到了人因化设计的一般原理,包括:满足认知和操作需求的信息显示设计;满足任务绩效的信息显示设计;满足班组合作与交流的信息显示设计;综合考虑,防止信息过负荷、工作过负荷和情境意识丧失。最后提出依据一般的人因化设计原理建立具体的信息显示设计细则,来指导信息显示的人因化设计,为提升设计水平和质量提供支持。 展开更多
关键词 信息显示 因化设计 数字人—机界面
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自旋因化法推求等效组态的原子谱项
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作者 聂五军 宋克敏 +1 位作者 陈希陵 冯玉玲 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 1996年第4期11-14,共4页
根据自族团化法的思想,提出了推求等效组态L-S耦合原子诺项的系统方法,并且运用C语言编制了计算程序。利用本程序可准确、快速地推求sN,pN,dN,...,xN。
关键词 等效组态 原子谱项 自旋因化 原子光谱
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电子束固化环氧树脂混合体系的研究 被引量:7
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作者 隋刚 仲伟虹 +1 位作者 张佐光 毛淑莉 《辐射研究与辐射工艺学报》 EI CAS CSCD 北大核心 2000年第4期252-256,共5页
对几种环氧树脂混合体系的电子束固化进行了研究。比较了环氧828、648、207树脂及其混合体系的辐射效应。分析了树脂配比及辐射剂量对环氧828/648树脂混合体系的影响;测试了不同树脂配比的环氧207/648树脂混合... 对几种环氧树脂混合体系的电子束固化进行了研究。比较了环氧828、648、207树脂及其混合体系的辐射效应。分析了树脂配比及辐射剂量对环氧828/648树脂混合体系的影响;测试了不同树脂配比的环氧207/648树脂混合体系辐射产物的性能。结果表明,环氧树脂的化学结构、空间效应以及结晶性等对其辐射效应有很大影响,通过不同环氧树脂的混合,可以改善体系的辐射固化效果,减少辐射剂量,提高辐射产物的性能。 展开更多
关键词 电子束 辐射因化 环氧树脂混合体系
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模拟高放废物玻璃固化体冲击试验研究
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作者 张传智 邵辅义 《辐射防护》 CAS CSCD 北大核心 1993年第1期60-63,共4页
本研究采用普通固体废物块冲击试验装置,对两种组分模拟高放废物玻璃固化体进行了冲击试验,研究了冲击能量、固化体组分对碎粒粒径分布的影响,估算了单位撞击能量所增加的表面积值,以建立玻璃固化体抗冲击性能的测试试验方法。
关键词 玻璃因化 冲击试验 高放废液
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原子吸收法测定放射性废物固化体中模拟核素钌 被引量:1
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作者 阮锦强 《南京化工大学学报》 1997年第2期89-92,共4页
研究了火焰原子吸收法测定放射性废物固化体浸出液中模拟核素钌的测定方法。对一些主要共存元素Si、Fe、Al、Ca、Mg对Ru测量的干扰和消除以及测定体系进行了研究。以1.2mol/LHCl+0.06mol/LH2SO4... 研究了火焰原子吸收法测定放射性废物固化体浸出液中模拟核素钌的测定方法。对一些主要共存元素Si、Fe、Al、Ca、Mg对Ru测量的干扰和消除以及测定体系进行了研究。以1.2mol/LHCl+0.06mol/LH2SO4作为测定体系,具有灵敏度高,测量稳定的特点,测量回收率在99%101%之间。 展开更多
关键词 原子吸收 放射性废物处理 因化处理
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国外关于稳定化/固化的有毒有害污染物的渗漏实验方法的研究进展 被引量:6
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作者 陈祖奇 安丽 《城市环境与城市生态》 CAS CSSCI CSCD 2000年第4期48-51,共4页
以水泥为基质的稳定化 /固化 (Stabilization/solidification)的方法在国外广泛用于无机、有机、有毒有害污染物的最终处置 ,已经有数十年的历史。论文较全面地介绍了拟合被这种稳定化 /固化过程处理过的污染物在自然界条件下短期和长... 以水泥为基质的稳定化 /固化 (Stabilization/solidification)的方法在国外广泛用于无机、有机、有毒有害污染物的最终处置 ,已经有数十年的历史。论文较全面地介绍了拟合被这种稳定化 /固化过程处理过的污染物在自然界条件下短期和长期的污染物泄漏过程 ,即所谓短期、长期的渗漏行为的实验方法和数学模型 ,并总结了现有几种用来模拟短期或长期渗漏行为的渗漏实验方法和适用于这些实验方法的数学预测模型的应用条件。 展开更多
关键词 有毒有害污染物 稳定 因化 固体废弃物 渗漏
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紫外光固化涂料的原料发展趋向(Ⅲ) 被引量:3
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作者 金林生 《现代涂料与涂装》 CAS 1999年第2期31-32,共2页
关键词 涂料 紫外光固 因化 原料
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广西难处理金矿固化焙烧氰化提金试验 被引量:8
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作者 邱美珍 韦丛中 +1 位作者 蒋奇亮 杜杰 《广西地质》 2002年第4期43-46,共4页
通过对广西六梅金矿、明山金矿、金牙金矿含高砷高硫难浸金矿石进行固化焙烧—氰化提金的试验研究 ,获得了砷、硫固定率分别为 99.0 3%、97.0 4 % ,金浸出率 92 .35 %的较好指标 ,为这类难浸金矿的开发 。
关键词 难浸金矿 因化焙烧 提金
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State Estimation Method for GNSS/INS/Visual Multi-sensor Fusion Based on Factor Graph Optimization for Unmanned System
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作者 ZHU Zekun YANG Zhong +2 位作者 XUE Bayang ZHANG Chi YANG Xin 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第S01期43-51,共9页
With the development of unmanned driving technology,intelligent robots and drones,high-precision localization,navigation and state estimation technologies have also made great progress.Traditional global navigation sa... With the development of unmanned driving technology,intelligent robots and drones,high-precision localization,navigation and state estimation technologies have also made great progress.Traditional global navigation satellite system/inertial navigation system(GNSS/INS)integrated navigation systems can provide high-precision navigation information continuously.However,when this system is applied to indoor or GNSS-denied environments,such as outdoor substations with strong electromagnetic interference and complex dense spaces,it is often unable to obtain high-precision GNSS positioning data.The positioning and orientation errors will diverge and accumulate rapidly,which cannot meet the high-precision localization requirements in large-scale and long-distance navigation scenarios.This paper proposes a method of high-precision state estimation with fusion of GNSS/INS/Vision using a nonlinear optimizer factor graph optimization as the basis for multi-source optimization.Through the collected experimental data and simulation results,this system shows good performance in the indoor environment and the environment with partial GNSS signal loss. 展开更多
关键词 state estimation multi-sensor fusion combined navigation factor graph optimization complex environments
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Influencing factors analysis of hard limestone reformation and strength weakening under acidic effect
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作者 HOU Ming-xiao HUANG Bing-xiang +2 位作者 ZHAO Xing-long JIAO Xue-jie ZHENG Chen-yang 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2446-2466,共21页
Roof disaster has always been an important factor restricting coal mine safety production.Acidic effect can reform the rock mass structure to weaken the macroscopic strength characteristics,which is an effective way t... Roof disaster has always been an important factor restricting coal mine safety production.Acidic effect can reform the rock mass structure to weaken the macroscopic strength characteristics,which is an effective way to control the hard limestone roof.In this study,the effects of various factors on the reaction characteristics and mechanical properties of limestone were analyzed.The results show that the acid with stronger hydrogen production capacity after ionization(pK_(a)<0)has more prominent damage to the mineral grains of limestone.When pKa increases from−8.00 to 15.70,uniaxial compressive strength and elastic modulus of limestone increase by 117.22%and 75.98%.The influence of acid concentration is manifested in the dissolution behavior of mineral crystals,the crystal defects caused by large-scale acid action will lead to the deterioration of limestone strength,and the strength after 15%concentration reformation can be reduced by 59.42%.The effect of acidification time on limestone has stages and is the most obvious in the initial metathesis reaction stage(within 60 min).The key to the strength damage of acidified limestone is the participation of hydrogen ions in the reaction system.Based on the analytic hierarchy process method,the influence weights of acid type,acid concentration and acidification time on strength are 24.30%,59.54% and 16.16%,respectively.The research results provide theoretical support for the acidification control of hard limestone roofs in coal mines. 展开更多
关键词 hard roof acidic effect structural reformation strength weakening influencing factors
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State of health prediction for lithium-ion batteries based on ensemble Gaussian process regression
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作者 HUI Zhouli WANG Ruijie +1 位作者 FENG Nana YANG Ming 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2024年第3期397-407,共11页
The performance of lithium-ion batteries(LIBs)gradually declines over time,making it critical to predict the battery’s state of health(SOH)in real-time.This paper presents a model that incorporates health indicators ... The performance of lithium-ion batteries(LIBs)gradually declines over time,making it critical to predict the battery’s state of health(SOH)in real-time.This paper presents a model that incorporates health indicators and ensemble Gaussian process regression(EGPR)to predict the SOH of LIBs.Firstly,the degradation process of an LIB is analyzed through indirect health indicators(HIs)derived from voltage and temperature during discharge.Next,the parameters in the EGPR model are optimized using the gannet optimization algorithm(GOA),and the EGPR is employed to estimate the SOH of LIBs.Finally,the proposed model is tested under various experimental scenarios and compared with other machine learning models.The effectiveness of EGPR model is demonstrated using the National Aeronautics and Space Administration(NASA)LIB.The root mean square error(RMSE)is maintained within 0.20%,and the mean absolute error(MAE)is below 0.16%,illustrating the proposed approach’s excellent predictive accuracy and wide applicability. 展开更多
关键词 lithium-ion batteryies(LIBs) ensemble Gaussian process regression(EGPR) state of health(SOH) health indicators(HIs) gannet optimization algorithm(GOA)
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AAV-mediated expression of p65shRNA and bone morphogenetic protein 4 synergistically enhances chondrocyte regeneration
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作者 Yu Yangyi Song Zhuoyue +2 位作者 Lian Qiang Ding Kang Li Guangheng 《中国组织工程研究》 CAS 北大核心 2025年第17期3537-3547,共11页
BACKGROUND:Adeno-associated virus(AAV)gene therapy has been proven to be reliable and safe for the treatment of osteoarthritis in recent years.However,given the complexity of osteoarthritis pathogenesis,single gene ma... BACKGROUND:Adeno-associated virus(AAV)gene therapy has been proven to be reliable and safe for the treatment of osteoarthritis in recent years.However,given the complexity of osteoarthritis pathogenesis,single gene manipulation for the treatment of osteoarthritis may not produce satisfactory results.Previous studies have shown that nuclear factorκB could promote the inflammatory pathway in osteoarthritic chondrocytes,and bone morphogenetic protein 4(BMP4)could promote cartilage regeneration.OBJECTIVE:To test whether combined application of AAV-p65shRNA and AAV-BMP4 will yield the synergistic effect on chondrocytes regeneration and osteoarthritis treatment.METHODS:Viral particles containing AAV-p65-shRNA and AAV-BMP4 were prepared.Their efficacy in inhibiting inflammation in chondrocytes and promoting chondrogenesis was assessed in vitro and in vivo by transfecting AAV-p65-shRNA or AAV-BMP4 into cells.The experiments were divided into five groups:PBS group;osteoarthritis group;AAV-BMP4 group;AAV-p65shRNA group;and BMP4-p65shRNA 1:1 group.Samples were collected at 4,12,and 24 weeks postoperatively.Tissue staining,including safranin O and Alcian blue,was applied after collecting articular tissue.Then,the optimal ratio between the two types of transfected viral particles was further investigated to improve the chondrogenic potential of mixed cells in vivo.RESULTS AND CONCLUSION:The combined application of AAV-p65shRNA and AAV-BMP4 together showed a synergistic effect on cartilage regeneration and osteoarthritis treatment.Mixed cells transfected with AAV-p65shRNA and AAV-BMP4 at a 1:1 ratio produced the most extracellular matrix synthesis(P<0.05).In vivo results also revealed that the combination of the two viruses had the highest regenerative potential for osteoarthritic cartilage(P<0.05).In the present study,we also discovered that the combined therapy had the maximum effect when the two viruses were administered in equal proportions.Decreasing either p65shRNA or BMP4 transfected cells resulted in less collagen II synthesis.This implies that inhibiting inflammation by p65shRNA and promoting regeneration by BMP4 are equally important for osteoarthritis treatment.These findings provide a new strategy for the treatment of early osteoarthritis by simultaneously inhibiting cartilage inflammation and promoting cartilage repair. 展开更多
关键词 OSTEOARTHRITIS adeno-associated virus bone morphogenetic protein 4 p65-short hairpin RNA gene therapy short hairpin RNA transforming growth factor-β1 extracellular matrix articular cartilage chondrocytes.
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Transcriptome Sequencing for Sugar and Flavonoid Metabolism in Prunus persica‘Jinxiangyu’
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作者 CHEN Wei-feng WANG Chun-fa +2 位作者 HUANG Jia LI Du ZHANG Liang-bo 《Agricultural Science & Technology》 CAS 2024年第2期18-25,共8页
In this study,high performance liquid chromatography(HPLC)and RNA-seq transcriptome sequencing were used to study the changes in soluble sugar components and flavonoids in Prunus persica‘Jinxiangyu’at different deve... In this study,high performance liquid chromatography(HPLC)and RNA-seq transcriptome sequencing were used to study the changes in soluble sugar components and flavonoids in Prunus persica‘Jinxiangyu’at different developmental stages(20–90 d after flowering)and screen the key genes regulating the formation of soluble sugar and flavonoids in the fruits.The results showed that 60–85 d after flowering was the key stage of quality formation of Prunus persica‘Jinxiangyu’,and the content of soluble sugar,soluble solid,fructose,and sucrose in the fruit increased significantly during this period.The sugar content of ripe fruits was mainly fructose and sucrose.The content of kaempferol glycoside was low in the fruit.Quercetin glycoside content was higher in the young fruit stage and decreased with fruit maturity.There were no anthocyanin compounds in the fruit.The expression levels of genes involved in flavonoid metabolism(ANS,DFR,F3H,FLS,4CL1,etc.)were low in the fruit.A total of 181 differentially expressed genes were identified during fruit development to participate in five sugar metabolism pathways,among which the SDH gene had a higher expression level,which continuously rised in the later stage of fruit development.It mainly promoted the accumulation of fructose content in the later stage of fruit development.The expression levels of SPS1,SS,and SS1 genes were continuously up-regulated,which played a key role in sucrose regulation.The higher expression levels of SUS3 and INVA genes in the early stage of fruit development promoted the degradation of sucrose. 展开更多
关键词 Yellow peach Sugar metabolism Flavonoid compounds Differential gene expression
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Studies of Transgenic Hybrid Poplar 741 Carrying Two Insect-resistant Genes 被引量:61
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作者 田颖川 郑均宝 +3 位作者 虞红梅 梁海永 李常青 王进茂 《Acta Botanica Sinica》 CSCD 2000年第3期263-268,共6页
Partially modified Bt Cry1Ac gene and the arrowhead proteinase inhibitor (API) gene were used to construct a plant transformation vector pBtiA and this construct was transferred into the genome of the hybrid popla... Partially modified Bt Cry1Ac gene and the arrowhead proteinase inhibitor (API) gene were used to construct a plant transformation vector pBtiA and this construct was transferred into the genome of the hybrid poplar 741 [ Populus alba L.×( P. davidiana Dode+ P. simonii Carr.)× P. tomentosa Carr.] by Agrobacterium _ mediated transformation. Ten kanamycin resistant plants have been regenerated. Upon insect bioassay using Clostera anachoreta (Fabricius), three of the examined plants were demonstrated to be highly resistant to the testing insects. The mortality of insect larvae on one plant was higher than 90% in 6 days after infestation and the growth of the survival larvae were seriously inhibited. Results of PCR and Southern blot analysis indicated that both Bt Cry1Ac gene and API gene were integrated as a single copy into the genomes of these three plants when Cry1Ac gene fragment was used as the probe. Protein dot blot immunoassay and ELISA analysis revealed that at least the Cry1Ac protein was produced in these three transgenic plants and the expression levels were estimated to be approximately 0.015% of the leaf total soluble protein. This is the first report on insect resistant transgenic hybrid poplar 741 that expresses two insecticidal protein genes. 展开更多
关键词 poplar 741 divalent insect resistant genes TRANSFORMATION
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Recent Progress in Elucidating the Structure, Function and Evolution of Disease Resistance Genes in Plants 被引量:28
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作者 刘金灵 刘雄伦 +1 位作者 戴良英 王国梁 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第9期765-776,共12页
Plants employ multifaceted mechanisms to fight with numerous pathogens in nature. Resistance (R) genes are the most effective weapons against pathogen invasion since they can specifically recognize the corresponding... Plants employ multifaceted mechanisms to fight with numerous pathogens in nature. Resistance (R) genes are the most effective weapons against pathogen invasion since they can specifically recognize the corresponding pathogen effectors or associated protein(s) to activate plant immune responses at the site of infection. Up to date, over 70 R genes have been isolated from various plant species. Most R proteins contain conserved motifs such as nucleotide-binding site (NBS), leucine-rich repeat (LRR), Toll-interleukin-1 receptor domain (TIR, homologous to cytoplasmic domains of the Drosophila Toll protein and the manamalian intefleukin-1 receptor), coiled-coil (CC) or leucine zipper (LZ) structure and protein kinase domain (PK). Recent results indicate that these domains play significant roles in R protein interactions with effector proteins from pathogens and in activating signal transduction pathways involved in innate immunity. This review highlights an overview of the recent progress in elucidating the structure, function and evolution of the isolated R genes in different plant-pathogen interaction systems. 展开更多
关键词 plant disease resistance gene defense signaling evolution of resistance gene cluster
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Sequence Variation and Molecular Evolution of Hormone-Sensitive Lipase Genes in Species of Bovidae 被引量:8
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作者 马志杰 钟金城 +3 位作者 陈智华 刘丽 常怀普 罗晓林 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第1期26-34,共9页
The partial sequences of exon Ⅰ of hormone-sensitive lipase (HSL) genes in yak (Bos grunniens), cattle (Bos taurus), zebu (Bos indicus), and buffalo (Bubalus bubalis) were analyzed. Comparisons of these seq... The partial sequences of exon Ⅰ of hormone-sensitive lipase (HSL) genes in yak (Bos grunniens), cattle (Bos taurus), zebu (Bos indicus), and buffalo (Bubalus bubalis) were analyzed. Comparisons of these sequences and the deduced amino acid sequences with the homologous HSL gene and protein sequences in other mammalian species including pig (Sus scrofa), human (Homo sapiens), mouse (Mus musculus), and rat (Rattus sp.) retrieved from the GenBank were carried out and finally a phylogenetic tree was constructed using the partial DNA sequences of the HSL genes in all species. The results showed that the homologies of the partial exon Ⅰ sequences of the HSL genes between yak and cattle, zebu, buffalo, pig, human, mouse, and rat were as high as 99.8%, 99.6%, 97.4%, 90.6%, 88.4%, 83.5%, and 82.3%, respectively. This was accompanied by highly homologous amino acid sequences of the HSLs: 100%, 100%, 98.2%, 94.0%, 92.2%, 89.8%, and 89.8% identity, respectively. There are more transitions, less transversions, and no insertion or deletion in variable nucleotides of the HSL genes between the yak and other species. The majority of the variable mutations was synonymous and was found most frequently at the third codon, followed by the first and second codons, a finding that was in accordance with the neutralism hypothesis for molecular evolution. In the phylogenetic tree, the cattle and zebu were clustered together first, followed by the yak, buffalo, pig, human, mouse, and rat. This was in agreement with taxonomy suggesting that the partial sequences of exon Ⅰ of the HSL genes were useful in constructing the phylogenetic tree of mammalian species. Among the four species of Bovidae, genetic differentiation in the HSL genes between yak and buffalo is equivalent to that between buffalo and cattle and between buffalo and zebu. Furthermore, the genetic distances in the HSL genes are much smaller between yak, cattle, and zebu than those between each of the three species and the buffalo. Therefore, it is reasonable to consider yak as an independent species of the genus Bos. 展开更多
关键词 BOVIDAE HSL gene PHYLOGENY evolution
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Pathogen_resistant Transgenic Plant of Brassica pekinensis by Transfering Antibacterial Peptide Gene and Its Genetic Stability 被引量:16
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作者 王关林 方宏筠 +2 位作者 王火旭 李洪艳 魏毓堂 《Acta Botanica Sinica》 CSCD 2002年第8期951-955,共5页
The soft rot infected by pathogenic bacterium Erwinia aroideae Holland is one of the three serious diseases of Chinese cabbage ( Brassica pekinensis Rupr.). By constructing vector system of high frequency transformati... The soft rot infected by pathogenic bacterium Erwinia aroideae Holland is one of the three serious diseases of Chinese cabbage ( Brassica pekinensis Rupr.). By constructing vector system of high frequency transformation mediated by Agrobacterium tunefaciens EHA105, anti-bacterial peptide gene with strong bactericidal action to pathogenic bacteria was introduced into Chinese cabbage AB-81 self-bred line and the transgenic plants were obtained. PCR and Southern blotting detection showed that target gene was integrated into plant genome of Chinese cabbage. The tests of bacteriostasis action of the extract from transgenic plants in vitro, and the assay of disease-resistant of transgenic plantlets in the tube and the pot by perfusing inoculation with pathogenic bacteria showed obvious resistance to soft rot. This resistance can be a stable heredity by genetic analysis of generations of transgenic plants self-bred, separation ratio of its R, was 3:1. The resistance to Km and disease of soft rot was still kept in the R-5. These results indicated the possibility of breeding new varieties of anti-soft rot Chinese cabbage by transgenic plants as parents. 展开更多
关键词 Brassica pekinensis antibacterial peptide gene TRANSFORMATION soft rot
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Growth Differentiation Factor-9 Gene Expression of Mice Oocytes in Vitro and in Vivo 被引量:5
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作者 彭宇洪 庄广伦 +2 位作者 周灿权 谢守珍 程冀平 《Zoological Research》 CAS CSCD 北大核心 2006年第5期456-460,共5页
Mice preantral follicles were cultured in vitro for 12 days to achieve metaphase Ⅱ (M Ⅱ ) oocytes. Oocyte growth differentiation factor-9 (GDF-9) gene expression was measured during different growth stages to ex... Mice preantral follicles were cultured in vitro for 12 days to achieve metaphase Ⅱ (M Ⅱ ) oocytes. Oocyte growth differentiation factor-9 (GDF-9) gene expression was measured during different growth stages to explore the relationship between oocyte maturation and GDF-9 gene expression. Preantral follicles of lO-day old mice were isolated from the ovaries and were cultured for 12 days. Oocytes from day 2 (D2), D4, D6, D8, DIO, D12 cultured in vitro were named the in vitro group and oocytes of day 12 (D12), D14, D16, D18, D20, D22 grown in vivo were named the in vivo group. Follicle survival, antrum formation and maturation rate were 89.5%, 51.8% and 56.6% respectively in follicles cultured in vitro. After RT-PCR and agarose gel electrophoresis, relative mRNA abundance of GDF-9 was measured in each group of oocytes. At day 8 - 12, the GDF-9 gene expression level of oocytes in vitro was significantly lower than that in vivo (P 〈 0.05). We conclude that M Ⅱ oocytes can be obtained from in vitro culture of preantral follicles. The GDF- 9 gene expression of oocytes varies at different growth stages in vivo. The low expression of GDF-9 in oocytes cuhured in vitro may be the cause of their low developmental capacity. 展开更多
关键词 MICE CULTURE OOCYTE Growth differention factor-9
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Diversity of Bmp15 and Gdf9 Genes in White Goat of Guizhou Province and Evolution of the Encoded Proteins 被引量:6
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作者 冉雪琴 林尖兵 +2 位作者 杜智勇 覃成 王嘉福 《Zoological Research》 CAS CSCD 北大核心 2009年第6期593-602,共10页
Members of the transforming growth factor-beta superfamily, growth differentiation factor 9 (GDF9) and bone morphogenetic protein 15 (BMP 15), have crucial roles in fecundity of sheep. Our previous investigation c... Members of the transforming growth factor-beta superfamily, growth differentiation factor 9 (GDF9) and bone morphogenetic protein 15 (BMP 15), have crucial roles in fecundity of sheep. Our previous investigation confirmed that the fecundity mutations of sheep presented in highly prolific White goat individuals of Guizhou province. To illuminate other polymorphisms in Bmpl5 and Gdfl) genes and the relationship of these mutations with function, we cloned and characterized the coding region of Bmp15 and Gdfl). Molecular models of BMP15 and GDF9 mature peptide of White goat were constructed based on the homology of human BMP7 experimental tertiary structure. Two exons encoded prepropeptide of 394 amino acids in BMPI5 and 453 residues in GDF9, respectively. Apart from the FecXs mutation (S99I) in BMP15 and V791 mutation in GDF9 confirmed in White goat previously, other seven and three polymorphism sites were detected from BMP15 and GDF9 mature peptides, respectively. S32G, N66H, S99I/P99I and G107R in BMP15 could be important for the binding of dimer to receptors. Changes of P78Q and V79I in GDF9 might affect the binding of dimer to receptor type t. Comparing the length of BMP 15 and GDF9 prepropeptide in vertebrates, an increase in length of BMP 15 presented along with the protein evolution from fish to mammal and the divergence of the N-terminus residues in matured BMP15 peptide might contribute to the sensitive control on the fertility of animal species with low ovulation rate. These findings gave a valuable explanation for the correlation of mutations in Bmpl5 and Gdfl) genes with the control on fecundity of White goat and supported the notion that they were the pivotal factors in female fertility of White goat in Guizhou province. 展开更多
关键词 BMP15 GDF9 Gene EVOLUTION White goat
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Agrobacterium _mediated Transformation of Rice with Help of Bombardment 被引量:10
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作者 明小天 苑华毅 +1 位作者 王莉江 陈章良 《Acta Botanica Sinica》 CSCD 2001年第1期72-76,共5页
Oryza sativa L. ssp. japonica cv. Zhonghua 8, which is recalcitrant to infection of Agrobacterium tumefaciens (Smith et Townsend) Conn strain EHA105 with ordinary binary vector pCambia 1301, was transformed through Ag... Oryza sativa L. ssp. japonica cv. Zhonghua 8, which is recalcitrant to infection of Agrobacterium tumefaciens (Smith et Townsend) Conn strain EHA105 with ordinary binary vector pCambia 1301, was transformed through Agrobacterium-mediated transformation with help of bombardment. The transformation efficiency can be raised greatly. Single copy of gene insertion in the genome of transgenic rice plants was proved by Southern analysis and the expression of GUS gene was observed. GUS gene and hygromycin-resistant gene show 3:1 segregation in progenies of the transgenic rice plants. 展开更多
关键词 AGROBACTERIUM BOMBARDMENT TRANSFORMATION RICE
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