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言语数词习得的认知基础
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作者 牟毅 《北京师范大学学报(社会科学版)》 CSSCI 北大核心 2024年第3期64-71,共8页
儿童从学前期开始学习言语数词(如理解数词的数量含义),但其认知基础为何尚有很大争议。现有研究聚焦检查儿童的数词概念是否建立于自婴儿期就具有的非言语数能力基础上。考虑到非言语数能力受到至少两个不同的数认知系统的支持(近似数... 儿童从学前期开始学习言语数词(如理解数词的数量含义),但其认知基础为何尚有很大争议。现有研究聚焦检查儿童的数词概念是否建立于自婴儿期就具有的非言语数能力基础上。考虑到非言语数能力受到至少两个不同的数认知系统的支持(近似数量系统和物体追踪系统),研究者检查数词概念习得是否依赖于这些数认知系统,并发展出四种假设:近似数量系统假设,物体追踪系统假设,双系统假设和独立假设。这些假设均有其合理性和局限性,检验四种假设的关键是同时纳入两个非言语数认知系统并对比它们对数词习得的贡献。在这个检验思路中,未来研究需提供追踪和干预训练数据检查两个非言语数认知系统和数词习得的关系,且将之在行为和大脑认知神经层面交叉印证;此外,对这些关系的检查还需注意区分儿童数词学习的不同阶段,并考虑其他一般性认知能力的影响。 展开更多
关键词 言语数词 基数性 继位 近似数量系统 物体追踪系统
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国产猪牙花属植物的比较核型研究 被引量:1
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作者 殷根深 翟书华 +1 位作者 刘开庆 陈子牛 《北方园艺》 CAS 北大核心 2018年第11期89-93,共5页
以国产猪牙花属植物2个种(新疆猪牙花、猪牙花)以及外来栽培种(Erythronium dens-canis L.)为研究对象,采用比较核型分析方法,分析了猪牙花属4个样本(新疆猪牙花及Erythronium dens-canis L.各1个,猪牙花2个)的核型数据,以期探讨新疆猪... 以国产猪牙花属植物2个种(新疆猪牙花、猪牙花)以及外来栽培种(Erythronium dens-canis L.)为研究对象,采用比较核型分析方法,分析了猪牙花属4个样本(新疆猪牙花及Erythronium dens-canis L.各1个,猪牙花2个)的核型数据,以期探讨新疆猪牙花的染色体异基数性的起源机制。结果表明:与其它2个种不同之处在于,新疆猪牙花第1、2号染色体为中部着丝点染色体;在4个样本中,新疆猪牙花染色体间不对称性最大,染色体内不对称性最小,这些结果均支持丝粒并合可能是新疆猪牙花染色体异基数性起源的主要机制。 展开更多
关键词 新疆猪牙花 染色体异基数性 着丝粒并合 比较核型分析
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全同粒子与真假孙悟空之比较研究
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作者 万小龙 姜小慧 《淮阴师范学院学报(哲学社会科学版)》 2010年第1期28-32,共5页
《西游记》中真假孙悟空的故事引人入胜,量子力学的全同粒子哲学问题让人疑惑不解;真假孙悟空经历了一系列的鉴别方法方才得出答案,全同粒子哲学问题同样经过了许多论证,但还是没有定论。真假孙悟空与全同粒子所涉及的一个共同问题就是... 《西游记》中真假孙悟空的故事引人入胜,量子力学的全同粒子哲学问题让人疑惑不解;真假孙悟空经历了一系列的鉴别方法方才得出答案,全同粒子哲学问题同样经过了许多论证,但还是没有定论。真假孙悟空与全同粒子所涉及的一个共同问题就是个体性,两者都从不可区分性开始,但是真假孙悟空的个体性没有丧失,全同粒子却被认为丧失了个体性。问题在于,全同粒子虽然没有序数性,但是还有基数性,基数性可以作为个体化的前提。因此,全同粒子的个体性至少是没有完全丧失的。 展开更多
关键词 真假孙悟空 全同粒子 不可区分 基数性 个体
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Research on Thermodynamic Properties of Polybrominated Diphenylamine by Neural Network 被引量:19
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作者 堵锡华 庄文昌 +1 位作者 史小琴 冯长君 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2015年第1期59-64,I0001,I0002,共8页
Based on the location of bromine substituents and conjugation matrix, a new substituent po- sition index ~X not only was defined, but also molecular shape indexes Km and electronega- tivity distance vectors Mm of diph... Based on the location of bromine substituents and conjugation matrix, a new substituent po- sition index ~X not only was defined, but also molecular shape indexes Km and electronega- tivity distance vectors Mm of diphenylamine and 209 kinds of polybrominated diphenylamine (PBDPA) molecules were calculated. Then the quantitative structure-property relationships (QSPR) among the thermodynamic properties of 210 organic pollutants and 0X, K3, M29, M36 were founded by Leaps-and-Bounds regression. Using the four structural parameters as input neurons of the artificial neural network, three satisfactory QSPR models with network structures of 4:21:1, 4:24:1, and 4:24:1 respectively, were achieved by the back-propagation algorithm. The total correlation coefficients R were 0.9999, 0.9997, and 0.9995 respectively and the standard errors S were 1.036, 1.469, and 1.510 respectively. The relative mean deviation between the predicted value and the experimental value of Sθ, AfHe and △fGθ- were 0.11%, 0.34% and 0.24% respectively, which indicated that the QSPR models had good stability and superior predictive ability. The results showed that there were good nonlinear correlations between the thermodynamic properties of PBDPAs and the four structural pa- rameters. Thus, it was concluded that the ANN models established by the new substituent position index were fully applicable to predict properties of PBDPAs. 展开更多
关键词 Polybrominated diphenylamine Neural networks Molecular shape index Elec-tronegativity distance vector Substituent position index Thermodynamic properties
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Identification of Quantitative Trait Loci for Cold Response of Seedling Vigor Traits in Rice 被引量:1
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作者 韩龙植 乔永利 +5 位作者 张三元 张媛媛 曹桂兰 金钟焕 李圭星 高熙宗 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第3期239-246,共8页
The quantitative trait loci (QTLs) for the seedling vigor traits under 12℃ cold water irrigation, such as the seedling height, the seedling fresh weight, the seedling dry weight, and their cold response index, were... The quantitative trait loci (QTLs) for the seedling vigor traits under 12℃ cold water irrigation, such as the seedling height, the seedling fresh weight, the seedling dry weight, and their cold response index, were identified using an F2:3 population including 200 individuals and lines derived from a cross of indica and japonica "Milyang 23/Jileng 1" with microsatellite markers. All seedling vigor traits exhibited a continuous distribution near normal in F3 lines; these traits were quantitative traits controlled by multiple genes. Twelve QTLs conferring the seedling vigor traits under cold water irrigation were detected on chromosomes 1, 2, 7, 8, and 12, which explained the observed phenotypic variance from 5.2% to 17.9%. Among them, qCSH2 and qCSH12 were located in RM262-RM263 on chromosome 2 and RM270-RM17 on chromosome 12, respectively, which were associated with the seedling height, qSDW12 and qCSDW1 were located in RM19-RM270 on chromosome 12 and RM 129-RM9 on chromosome 1, respectively, which were correlated with the seedling dry weight and its cold response index, and the explained 16.6%, 17.9%, 15.9%, and 16.2% of the observed phenotypic variation, respectively. These QTLs alleles were derived from cold-tolerant parent Jileng 1; the gene actions of the two front genes showed their additive effect, and the two genes belind showed dominant and over dominant effects, respectively. 展开更多
关键词 RICE seedling vigor cold water irrigation QTLS
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QTL Mapping of Yield and Yield Components for Elite Hybrid Derived-RILs in Upland Cotton 被引量:7
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作者 汪保华 郭旺珍 +3 位作者 朱协飞 武耀廷 黄乃泰 张天真 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第1期35-45,共11页
A population of 180 recombinant inbred lines (RILs) was developed by single seed descended from the cross of high yield Upland cotton (Gossypium hirsutum L.) varieties Zhongmiansuo12 (ZMSI2) and 8891, the two pa... A population of 180 recombinant inbred lines (RILs) was developed by single seed descended from the cross of high yield Upland cotton (Gossypium hirsutum L.) varieties Zhongmiansuo12 (ZMSI2) and 8891, the two parents of Xiangzamian2 (XZM2). A genetic linkage map consisting of 132 loci and covering 865.20 cM was constructed using the RIL population chiefly with SSR markers. Yield and yield components were investigated for RILs in three environments in China. The purpose of the present research was to analyze the relationship between yield and its components and to map QTL for yield and yield components in cotton. QTL were tagged with data sets from single environment (separate analysis) and a set of data from means of the three environments (joint analysis). A total of 34 QTL for yield and yield components were independently detected in three environments, whereas fifteen QTL were found in joint analysis. Notably, a stable lint percentage QTL qLP-A10-1 was detected both in joint analysis and in two environments of separate analysis, which might be of special value for marker-assisted selection. The QTL detected in the present study provide new information on improving yield and yield components. Results of path analysis showed that bolls/plant had the largest contribution to lint yield, which is consistent with the mid-parent heterosis value in F1. Accordingly, in cotton breeding, bolls/plant can be considered first and other yield components measured as a whole to implement variety enhancement and hybrid selection of cotton. 展开更多
关键词 QTL mapping yield and yield components recombinant inbred lines cotton breeding
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An Entropy-based Index for Fine-scale Mapping of QTL
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作者 向阳 李玉梅 +1 位作者 刘再明 孙振球 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第4期373-380,共8页
By comparing the entropy and conditional entropy in a marker, an entropy-based index for fine-scale linkage-disequilibrium gene mapping is presented using high-density marker maps in extreme samples for quantitative t... By comparing the entropy and conditional entropy in a marker, an entropy-based index for fine-scale linkage-disequilibrium gene mapping is presented using high-density marker maps in extreme samples for quantitative trait. The entropy-based index is the function of LD between the marker and the traitlocus and does not depend on marker allele frequencies across the loci. It is parallel to Hardy-Weinberg disequilibrium (HWD) measure for QTL fine mapping, but its power of fine mapping QTL is higher than that of HWD measure. Through simulations, the fine mapping performance of this entropy-based index is investigated extensively under various genetic parameters. The results show that the indices presented here are both robust and powerful. 展开更多
关键词 ENTROPY entropy-based Index QTL fine mapping
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Integrity of Four Theories on Natural Selection Unit 被引量:1
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作者 韦文惠 陈奇 李大林 《Agricultural Science & Technology》 CAS 2012年第3期481-484,491,共5页
[Objective] The aim was to study the internal relationship of the four theories on natural selection unit. [Method] The value field of fitness of heterozygote was investigated by constructing mathematical models, to c... [Objective] The aim was to study the internal relationship of the four theories on natural selection unit. [Method] The value field of fitness of heterozygote was investigated by constructing mathematical models, to clarify the internal relations of the four theories on natural selection unit. [Result] According to mathematical modes constructed in the study, only the mutated genes meet the requirements of natural selection on heterozygous and homozygous aspects, as well as show high fitness in heterozygous condition, could the mutated genes be kept, giving consideration to both individual and population adaptation. Thus, this methodology theoretically inte- grates the theories of individual selection, collective selection, and genetic selection as well as Kimura's neutral theory of health information. [Conclusion] The result of this study suggested that the four theories on natural selection unit can co-exist, and share common premises. 展开更多
关键词 Individual selection Collective selection Genetic selection Neutral theory Mathematical model
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Determination of undrained shear strength using piezocone penetration test in clayey soil for bridge foundation 被引量:5
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作者 童立元 王强 +2 位作者 杜广印 刘松玉 蔡国军 《Journal of Southeast University(English Edition)》 EI CAS 2011年第2期201-205,共5页
In order to obtain the reasonable undrained shear strength Su for geotechnical analyses of bridge foundations in Yangtze River floodplain clayey soils, a site-specific study is conducted using the imported piezocone p... In order to obtain the reasonable undrained shear strength Su for geotechnical analyses of bridge foundations in Yangtze River floodplain clayey soils, a site-specific study is conducted using the imported piezocone penetration test (CPTu) with dissipation phases at the Fourth Nanjing Yangtze River Bridge construction sites. Taking the values of Su from laboratory tests as references, several existing Su-predicted methods based on CPTu are compared and evaluated. To verify the presented cone factor Nk, additional test sites are selected and examined. The results show that the values of cone factors such as Nkt, Nke, and Nau, depend on the shear test mode and disturbance. Generally, the values of Nke show more scattering than those of Nkt and N△u. For the stratified and layered sediments of the Yangtze River floodplain, it is recommended using the net cone resistance qT to estimate Su and the preliminary cone factor values Nkt are from 7 to 16, with an average of 11. It is also confirmed that the CPTu test, as a new technique in site characterization, can present reasonable parameters for bridge foundations. 展开更多
关键词 undrained shear strength piezocone penetrationtest clayey soil cone factor bridge foundation
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QTLs Mapping for Salinity Tolerance at Seedling Stage or Rice(Oryza sativa L.) Using Chromosome Segment Substitution Lines
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作者 林静 张所兵 +2 位作者 张云辉 汪迎节 方先文 《Agricultural Science & Technology》 CAS 2017年第12期2209-2211,共3页
In this study, a population of chromosome segment substitution lines (CSSLs) derived from the cross between 9311 (indica) and Nipponbare (japonica) was employed to map the quantitative trait loci (QTLs) for sa... In this study, a population of chromosome segment substitution lines (CSSLs) derived from the cross between 9311 (indica) and Nipponbare (japonica) was employed to map the quantitative trait loci (QTLs) for salt tolerance under the salt stress simulated with 0.5% NaCI, using survival rate as the index. The data were analyzed by QTL IciMapping v3.1, and the results showed that one QTL (QSsr3) related to salt tolerance was located in the vicinity of the marker RM1350 on chromosome 3, into a genetic interval of 113.2-132.8 cM, with a contribution rate of 17.75%. The additive effect was 10.9, indicating that the QTL derived from the parent Nipponbare improved the salt tolerance of rice at seedling stage. This study will provide a theoretical basis for the selection of salt tolerant rice germplasm. 展开更多
关键词 RICE Salt tolerance Chromosome segment substitution lines (CSSLs) Quantitative trait loci (QTLs) mapping
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Mapping QTLs Associated with Sheath Blight Resistance Using Chromosome Segment Substitution Lines of Rice(Oryza sativa L.)
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作者 林静 张所兵 +2 位作者 张云辉 汪迎节 方先文 《Agricultural Science & Technology》 CAS 2014年第5期756-759,共4页
In this study, a population of 119 chromosome segment substitution lines (CSSLs) derived from backcross between indica 9311 and japonica Nipponbare was employed to map quantitative trait loci (QTL) associated with... In this study, a population of 119 chromosome segment substitution lines (CSSLs) derived from backcross between indica 9311 and japonica Nipponbare was employed to map quantitative trait loci (QTL) associated with sheath blight resis-tance in rice with toothpick inoculation method. A total of three sheath blight resis-tance-associated QTLs (qsb8-1, qsb8-2 and qsb8-3) were identified, which were lo-cated on adjacent molecular markers RM3262, RM5485 and RM3496 of chromo-some 8; the genetic interval was 81.7cM-91.7cM, 91.7cM-108.1cM and 108.1cM-119.6cM, respectively. The additive effect of qsb8-2 was negative, indicating that sheath blight resistance of susceptible parent harboring qsb8-2 fragment was en-hanced; additive effects of qsb8-1 and qsb8-3 were positive, indicating that sheath blight resistance of susceptible parent harboring qsb8-1 and qsb8-3 fragments was reduced. 展开更多
关键词 RICE Sheath blight resistance Chromosome segment substitution lines(CSSLs) Quantitative trait locus (QTL) mapping
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Analysis of Quantitative Trait Loci for Starch Properties of Rice Based on an RIL Population 被引量:11
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作者 包劲松 Harold CORKE +1 位作者 何平 朱立煌 《Acta Botanica Sinica》 CSCD 2003年第8期986-994,共9页
Rice (Oryza sativa L.) eating and cooking quality is mainly influenced by its starch properties. Mapping quantitative trait loci (QTL) for starch properties not only helps us understand their genetic basis leading to ... Rice (Oryza sativa L.) eating and cooking quality is mainly influenced by its starch properties. Mapping quantitative trait loci (QTL) for starch properties not only helps us understand their genetic basis leading to acceleration of quality improvement, but also helps us find possible genes participating in the synthesis of starch. A recombinant inbred line (RIL) population consisting of 107 lines, derived from an indica (Zaiyeqing 8, ZYQ 8) and a japonica (Jingxi 17, JX 17) rice, was used to investigate the genetic factors affecting starch quality parameters, such as apparent amylose content (AAC), gel consistency (GC), starch pasting viscosity parameters, gel textural properties, gelatinization temperature (GT) and starch retrogradation properties. A total of 44 QTLs covered chromosomes 2-6, 8, 9 and 11 were detected for the 22 traits, with at least one QTL and as many as four QTLs for each individual trait. The results indicated that two major genes were responsible for most starch property traits. The Wx gene that encodes granule bound starch synthase on chromosome 6 was significant for AAC, GC, starch pasting viscosity parameters, gel textural properties and starch retrogradation properties. The alk gene linked with Wx on chromosome 6 was significant for starch gelatinization temperature characteristics. All other QTLs were minor genes. One QTL on chromosome 9 flanked by RZ404 and G295 was significant for gel hardness (HD), gumminess (GUM), chewiness (CHEW), peak temperature of retrogradated starch (RTp), and percentage retrogradation (R%) and all these traits were not tested before. 展开更多
关键词 ALK eating and cooking quality quantitative trait locus RICE STARCH WX
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Analysis of radial basis function interpolation approach 被引量:4
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作者 邹友龙 胡法龙 +3 位作者 周灿灿 李潮流 李长喜 Keh-Jim Dunn 《Applied Geophysics》 SCIE CSCD 2013年第4期397-410,511,共15页
The radial basis function (RBF) interpolation approach proposed by Freedman is used to solve inverse problems encountered in well-logging and other petrophysical issues. The approach is to predict petrophysical prop... The radial basis function (RBF) interpolation approach proposed by Freedman is used to solve inverse problems encountered in well-logging and other petrophysical issues. The approach is to predict petrophysical properties in the laboratory on the basis of physical rock datasets, which include the formation factor, viscosity, permeability, and molecular composition. However, this approach does not consider the effect of spatial distribution of the calibration data on the interpolation result. This study proposes a new RBF interpolation approach based on the Freedman's RBF interpolation approach, by which the unit basis functions are uniformly populated in the space domain. The inverse results of the two approaches are comparatively analyzed by using our datasets. We determine that although the interpolation effects of the two approaches are equivalent, the new approach is more flexible and beneficial for reducing the number of basis functions when the database is large, resulting in simplification of the interpolation function expression. However, the predicted results of the central data are not sufficiently satisfied when the data clusters are far apart. 展开更多
关键词 Inverse problems radial basis function interpolation new approach
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A Novel CMOS Voltage Reference Based on Threshold Voltage Difference Between p-Type and n-Type MOSFETs
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作者 孔明 郭健民 +1 位作者 张科 李文宏 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第10期1546-1550,共5页
A novel MOS-only voltage reference is presented,which is based on the threshold voltage difference between p-type and n-type MOSFETs. Its precision is improved by the cancellation of the process variation. The referen... A novel MOS-only voltage reference is presented,which is based on the threshold voltage difference between p-type and n-type MOSFETs. Its precision is improved by the cancellation of the process variation. The reference has been successfully implemented in a Chartered 0.35μm CMOS process. The occupied chip area is 0. 022mm^2. Measurements indicate that without trimming, the average output voltage error is 6mV at room temperature compared with the simulation result. The temperature coefficient is 180ppm/℃ in the worst case in the temperature range of 0 to 100℃ ,and the line regulation is ± 1.1%. The reference is applied in an adaptive power MOSFET driver. 展开更多
关键词 MOS-only voltage reference threshold voltage temperature coefficient line regulation
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Analysis and Evaluation Indicator Selection of Chilling Tolerance of Different Cotton Genotypes 被引量:2
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作者 武辉 侯丽丽 +4 位作者 周艳飞 范志超 石俊毅 阿丽艳.肉孜 张巨松 《Agricultural Science & Technology》 CAS 2012年第11期2338-2346,共9页
[Objectivc] This study aimed to investigate the chilling tolerance of seedlings of different cotton genotypes and screen appropriate indicators for assess- ing chilling tolerance, to establish reliable mathematical ev... [Objectivc] This study aimed to investigate the chilling tolerance of seedlings of different cotton genotypes and screen appropriate indicators for assess- ing chilling tolerance, to establish reliable mathematical evaluation model for chilling tolerance of cotton, thus providing theoretical basis for breeding and promoting new chilling-tolerant cotton germplasms and large-scale evaluation of chilling tolerance of cotton varieties. [Method] Fifteen cotton varieties (lines) were used as experimental materials. The photosynthetic gas exchange parameters, chlorophyll fluorescence ki- netic parameters, chlorophyll content, relative soluble sugar content, malonaldehyde content, relative proiine content, relative conductivity and other 12 physiological indi- cators of seedling leaves under low temperature treatment (5 ℃, 12 h) and recovery treatment (25 ℃. 24 h) were determined; based on the chilling tolerance coefficient (CTC) of various individual indicators, the comprehensive evaluation of chilling toler- ance was conducled by using principal component analysis, hierarchical cluster anal- ysis and stepwise regression analysis. [Result] The results showed that the 12 indi- vidual physiological indicators could be classified into 7 independent comprehensive components by principal component analysis; 15 cotton varieties (lines) were clus- tered into three categories by using membership function method and hierarchical cluster analysis; the mathematical model for evaluating chilling tolerance of cotton seedlings was established: D =0.275 -0.244Fo1 +0.206Fv/Fm1+0.326g,%-0.056SS + 0.225MDA+O.O38REC (FF=0.995), and the evaluation accuracy of the equation was higher than 94.25%,0. Six identification indicators closely related to chilling tolerance were screened, including Fo,, Fv/Fm1, Seedling leaves of cotton varieties (lines) gs2, SS, MDA, and REC. [Conclusion] with high chilling tolerance are less dam- aged under low temperature stress, and are able to maintain relatively high photo- synthetic electron transport capacity and high stomatal conductance after recovery treatment, which is contributed to gas exchange and recovery of photosynthetic ca- pacity. Determination of the six indicators under the same stress condition can be adopted for rapid identification and prediction of the chilling tolerance of other cotton varieties, which provides basis for the breeding, promotion, identification and screen- ing of chilling tolerant germplasms. 展开更多
关键词 COTTON Chilling tolerance Principal components analysis Comprehensiveevaluation Stepwise regression analysis
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Relationship between IFN-γ gene polymorphism and susceptibility to intrauterine HBV infection 被引量:14
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作者 Hui Yu Qi-Rong Zhu Shao-Qing Gu Lin-E Fei 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第18期2928-2931,共4页
AIM: To explore the susceptibility of children to intrauterine HBV infection by studying the relationship between IFN-γ gene polymorphism, including IFN-γ+874A/T single nucleotide polymorphism(SNP) and CA repeat... AIM: To explore the susceptibility of children to intrauterine HBV infection by studying the relationship between IFN-γ gene polymorphism, including IFN-γ+874A/T single nucleotide polymorphism(SNP) and CA repeat microsatellite polymorphism and intrauterine HBV infection. METHODS: A TaqMan fluorescence polymerase chain reaction in the IFN-γ+874A/T single nucleotide polymorphism was tested in the intrauterine HBV infection group(group Ⅰ) and the normal immune children group(group Ⅱ). Capillary electrophoresis was performed in the above two groups to assay the IFN-γ, CA repeat microsatellite polymorphism. RESULTS: Frequencies of AA, AT and TT genotypes were 67.4%, 19.6% and 13.0% in the intrauterine HBV infection group, and 45.2%, 30.1% and 24.7% in the normal immune children group, respectively. A significant difference was found in the frequency distribution of IFN-γ+874 genotype between the two groups (x^2 = 5.102, P = 0.02389). In the intrauterine HBV infection group the AA genotype was more common than in the normal immune group. Frequency of IFN-γ+874A allele was 77.17% in the intrauterine HBV infection group, and 60.27% in the normal immune children group. In the intrauterine HBV infection group the IFN-γ+874A allele was more common than in normal immune group. A significant difference was found in the frequency distribution between the two groups (x^2= 7.238, P= 0.02389, OR = 2.228, 95% CI = 1.244-3.992). (CA12)^+/(CA12)^+ of IFN-γ CA microsatellite polymorphism was 11.90% in the intrauterine HBV infection group and 26.47% in the normal immune children group. A significant difference was found in the frequency distribution between the two groups (x^2 = 5.64, P = 0.0176). Frequency of IFN-γ CA repeat was 25% in the intrauterine HBV infection group and 43.38% in the normal immune children group. The frequency of IFN-γ CA repeat was less in the intrauterine HBV infection group than in normal immune group. A significant difference was found in the frequency distribution between the two groups (x^2 = 7.548, P= 0.0060). CONCLUSION: There is a relationship between IFN-γ+874A/T SNP and intrauterine HBV infection as well as between IFN-γ CA microsatellite polymorphism and intrauterine HBV infection. IFN-γ gene polymorphism might be important in determining individual's susceptibility to intrauterine HBV infection. 展开更多
关键词 INTERFERON-Γ Gene polymorphism Hepatitis B virus INTRAUTERINE
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Improved Learning Algorithm of Hyperball CMAC and Its Convergence Analysis 被引量:3
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作者 罗健旭 邵惠鹤 《Journal of Shanghai Jiaotong university(Science)》 EI 2004年第3期21-24,共4页
An improved learning algorithm for hyperball CMAC was presented. Only one parameter is needed to determine the learning rate, and the parameter can be obtained by a self-optimizing method. The convergence of the impro... An improved learning algorithm for hyperball CMAC was presented. Only one parameter is needed to determine the learning rate, and the parameter can be obtained by a self-optimizing method. The convergence of the improved learning algorithm was proved. The simulation research shows that the learning speed and the learning accuracy are both improved. 展开更多
关键词 hyperball CMAC basis function CONVERGENCE
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Symmetry Breaking Ground States of Bose-Einstein Condensates in 1D Double Square Well and Optical Lattice Well 被引量:1
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作者 YUANQing-Xin DINGGuo-Hui 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第5期814-818,共5页
We investigate the phenomena of symmetry breaking and phase transition in theground state of Bose-Einstein condensates (BECs) trapped in a double square well and in an opticallattice well, respectively. By using stand... We investigate the phenomena of symmetry breaking and phase transition in theground state of Bose-Einstein condensates (BECs) trapped in a double square well and in an opticallattice well, respectively. By using standing-wave expansion method, we present symmetric andasymmetric ground state solutions of nonlinear Schroedinger equation (NLSE) with a symmetric doublesquare well potential for attractive nonlinearity. In particular, we study the ground state wavefunction's properties by changing the depth of potential and atomic interactions (here we restrictourselves to the attractive regime). By using the Fourier grid Hamiltonian method, we also reveal aphase transition of BECs trapped in one-dimensional optical lattice potential. 展开更多
关键词 Bose-Einstein condensates symmetry breaking state phase transition
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Implicit modeling of complex orebody with constraints of geological rules 被引量:14
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作者 De-yun ZHONG Li-guan WANG +1 位作者 Lin BI Ming-tao JIA 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第11期2392-2399,共8页
To dynamically update the shape of orebody according to the knowledge of a structural geologist’s insight,an approach of orebody implicit modeling from raw drillhole data using the generalized radial basis function i... To dynamically update the shape of orebody according to the knowledge of a structural geologist’s insight,an approach of orebody implicit modeling from raw drillhole data using the generalized radial basis function interpolant was presented.A variety of constraint rules,including geology trend line,geology constraint line,geology trend surface,geology constraint surface and anisotropy,which can be converted into interpolation constraints,were developed to dynamically control the geology trends.Combined with the interactive tools of constraint rules,this method can avoid the shortcomings of the explicit modeling method based on the contour stitching,such as poor model quality,and is difficult to update dynamically,and simplify the modeling process of orebody.The results of numerical experiments show that the 3D ore body model can be reconstructed quickly,accurately and dynamically by the implicit modeling method. 展开更多
关键词 three-dimensional geomodeling implicit modeling radial basis function structural anisotropy geological rules
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Analysis of digenic epistatic effects and QE interaction effects QTL controlling grain weight in rice 被引量:11
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作者 高用明 朱军 +3 位作者 宋佑胜 何慈信 石春海 邢永忠 《Journal of Zhejiang University Science》 EI CSCD 2004年第4期371-377,共7页
Immortalized F2 population of rice (Oryza sativa L.) was developed by randomly mating F1 among recombinant inbred (RI) lines derived from (Zhenshan 97B×Minghui 63),which allowed replications within and across env... Immortalized F2 population of rice (Oryza sativa L.) was developed by randomly mating F1 among recombinant inbred (RI) lines derived from (Zhenshan 97B×Minghui 63),which allowed replications within and across environments.QTL (quantitative trait loci) mapping analysis on kilo-grain weight of immortalized F2 population was performed by using newly developed software for QTL mapping,QTL Mapper 2.0. Eleven distinctly digenic epistatic loci included a total of 15 QTL were located on eight chromosomes.QTL main effects of additive,dominance,and additive×additive,additive×dominance,and dominance×dominance interactions were estimated.Interaction effects between QTL main effects and environments (QE) were predicted.Less than 40% of single effects,most of which were additive effects,for identified QTL were significant at 5% level.The directional difference for QTL main effects suggested that these QTL were distributed in parents in the repulsion phase.This should make it feasible to improve kilo-grain weight of both parents by selecting appropriate new recombinants. Only few of the QE interaction effects were significant.Application prospect for QTL mapping achievements in genetic breeding was discussed. 展开更多
关键词 Immortalized F_2 population RICE Kilo-grain weight QTL EPISTASIS QTL×environment
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