基于关联规则的图书馆个性化服务研究

关联规则挖掘技术是一种新兴的数据处理技术,其算法及应用在图书馆中起着非常重要的作用。Apriori算法是关联规则挖掘的经典算法,在分析Apriori算法的基础上,提出利用FP-tree生成树技术来减少候选集的数量,克服Apriori算法的弱点,以提高图书馆个性化服务的效率。     

青稞遗传多样性及其农艺性状与SSR标记的关联分析

利用92个SSR标记对108份青稞亲本材料进行多态性扫描,分析其遗传多样性,旨在寻找与农艺性状相关联的分子标记,为青稞杂交组合的配制及分子标记辅助育种提供依据。挑选48个多态性标记进行群体遗传结构分析,在此基础上采用Tassel 2.1 GLM (general linear model)和MLM (mixed linear model)方法进行标记与农艺性状的关联分析。共检测出156个等位变异,每个位点2~6个等位变异。供试群体的Shannon指数为0.6727~1.1368,材料间遗传相似系数为0.2250~1.0000,平均0.7585。通过群体遗传结构分析将供试材料划分成4个亚群。以GLM分析,发现12个与株高、穗长、穗粒数和分蘖数相关联的标记,对表型变异的解释率分别为11.5%~17.6%、19.4%~45.4%、15.4%~22.1%和29.2%;以MLM分析,发现8个与株高、分蘖数和小穗数相关的标记,各标记对表型变异的解释率分别为31.7%~49.8%、28.1%~37.2%、22.7%~32.7%。关联标记分布在基因组全部6个连锁群上。     

The community idea in American country life

The American Country LifeAssociation was heir to Theodore Roosevelt'sCountry Life Commission, which examined thegeneral conditions of farming life in the opencountry, and...its larger problems. In1919, Kenyon Butterfield, a member ofRoosevelt's Commission, met withrepresentatives from 30 states and 25 nationalorganizations to form the American Country LifeAssociation. In that year, Butterfield, ACLA'sfirst president, published a book, TheFarmer and the New Day, whose defining chapterwas The Making of Communities: The CommunityIdea. The ACLA was educator created and led.Solutions to rural problems were seen aseducational matters. But educational philosophywas undergoing scrutiny and new educationalconcepts were arising from the bustling,industrializing, urbanizing times of late19th century. The experimental,unconstrained spirit of the nation at the turnof the century was formalized as pragmatism. Aleading pragmatist and educator of the time wasJohn Dewey, a contemporary of Butterfield.The communitarianism of Butterfield and Deweycarried throughout the life of ACLA in avariety of forms. Even after ACLA ended as anorganization in 1976, the concerns and idealscontinued in successor organizations, and canbe found in environmental, sustainableagriculture, and rural life organizationstoday. This paper traces one of continuingthemes of the ACLA, the community idea as a wayof adding a social dimension to agriculture'seconomic policies and development. The ACLAstory is a metaphor for country life throughmuch of 20th century America. ACLA is alsoa lesson in how organizations come into being,flourish, falter, die, and leave their legaciesto future generations.     

KIT基因多态性与荷斯坦牛着色性状的关联分析

牛的被毛颜色是重要的外貌性状。本研究采集北京地区401头荷斯坦母牛血样及21头公牛冻精样品．提取基因组DNA,选取牛6号染色体上KIT基因的4个SNPs位点,利用飞行时间质谱技术检测基因型。通过数码相机照相并进行图像分析计算牛的被毛黑白比例,记录乳头颜色。将基因型和表型数据进行关联分析,结果显示KIT基因的G72792875T住点对被毛比例有显著影响（P〈0．05）,推测KIT基因可能与荷斯坦牛的着色性状的形成相关。     

“清如玉壶冰”——怀念爷爷吴觉农的朋友、茶人何耀曾先生

何耀曾先生（1920—2010）是重庆复旦大学茶叶专修科的第一届毕业生（1944）,从那时起,他为中国茶业的兴盛工作了六十多年。在他去世前的三年里,我曾多次访问他,记下了他的回忆和他与张志澄、钱梁、吴觉农先生的往来。     

猪FRZB、ABCF1基因多态性与生长性状的关联分析

FRZB基因通过抑制Wnt信号途径调控细胞生长,ABCF1(也称为ABC50)结合e IF2,在翻译起始中发挥着重要的作用,可作为猪生长性状相关的候选基因。本研究采用直接测序法检测FRZB基因和ABCF1基因5'非翻译区中单核苷酸多态性(SNPs)基因型分布,并分析基因型与生长性状的相关性。结果表明:在美系大白猪中,FRZB基因位点ins(A-532G)多态性与背膘厚呈极显著相关(P0.01),与体长接近显著水平(P=0.05);ABCF1基因254A/G多态性与背膘厚、左乳头数和右乳头数均呈显著相关(P0.05);在法系大白中,ABCF1基因254A/G多态性与初生重呈显著相关(P0.05)。结果表明,FRZB和ABCF1基因是潜在的影响猪生长性状的候选基因。     

Expression profiles and associations of FGF1 and FGF10 with intramuscular fat in Tibetan chicken

ABSTRACT

1. FGF1 and FGF10, two paracrine members of the fibroblast growth factor (FGF) gene family, play critical roles in the development, structural and metabolic remodelling of adipose tissue.

2. The objective of this study was to investigate the expression profiles of FGF1 and FGF10 genes in breast muscle and thigh muscle in 5 developmental stages (1, 81, 119, 154 and 210 d old) in Tibetan chickens. The possible relationships between expression of these genes and intramuscular fat (IMF) content were analysed in Tibetan chickens.

3. Expression profiles showed that FGF1 and FGF10 mRNA were ubiquitously expressed in various tissues of 154-d-old Tibetan chickens. Lung tissue contained the highest amount of FGF1 and FGF10 mRNA while breast muscle and thigh muscle exhibited lower levels of FGF1 and FGF10 mRNA in both males and females compared with other tissues (P < 0.05). Temporal expression of FGF1 and FGF10 in breast and thigh muscle showed similar tendencies in males and females, respectively, with peaks in thigh muscle at 119-d-old and breast muscle in 1-d-old males and females, respectively.

4. Correlation analysis suggested that gender had an influence on the relationships of FGF1 and FGF10 expression with IMF content in thigh muscle. The RNA levels of FGF1 and FGF10 genes in male thigh muscle were positively related to IMF content of Tibetan chickens (P < 0.01), while the correlations were shown to be negative in female thigh muscle (P > 0.05).

5. These results provide a basis for functional elucidation of FGF1 and FGF10 genes on adipocyte development and intramuscular fat deposition, as well as selective breeding and resource exploration of local poultry breeds.     

Detection of novel single-nucleotide polymorphisms (SNPs) in the CYP21 gene and association analysis of two SNPs for CYP21 and ESR2 with litter size in a commercial sow population

Altogether 129 F₁ sows from a commercial sow farm with at least four litters were genotyped for the oestrogen receptor 2 gene (ESR2) and cytochrome P450 hydroxylase 21 gene (CYP21) and investigated for associations on the litter‐size parameters: total number born and number born alive. Five novel polymorphisms were found in the 3′‐untranslated region for the CYP21 gene. Genotype and allele frequencies for the CYP21 (position 3462G > A) single‐nucleotide polymorphism (SNP) were 0.434 (GG), 0.504 (AG), 0.062 (AA) and 0.69 (G):0.31 (A), respectively. No association was found between this polymorphism and litter‐size parameters. For the ESR2 gene, the SNP in exon 5 associated with an amino acid substitution MET (allele A) > VAL (allele G) was investigated. Only two genotypes were found leading to allele frequencies of 0.34 (A):0.66 (G). Only number born alive piglets were significantly increased for the AG genotype (p = 0.034) with 11.64 piglets per sow and litter in comparison with the GG genotype, leading to only 10.96 piglets per sow and litter. From these data, it can be concluded that the investigated SNP of the ESR2 gene is associated with the number of liveborn piglets in the commercial population considered, and hence could be useful in selection for litter size. Therefore, this gene should be investigated in additional populations.     

小麦南大2419及其衍生品种(系)主要农艺性状的关联分析

筛选与小麦重要农艺性状相关联的SSR标记,对小麦分子标记辅助育种有重要的实践意义.本研究利用多态性较高的80个SSR标记,对南大2419及其71份衍生后代品种(系)进行基因型分析,采用TASSEL软件的MLM (Mixed linear model)方法对籽粒产量、千粒重、有效穗、穗粒数等8个主要农艺性状进行SSR标记...     

中国栽培和野生大豆农艺品质性状与SSR标记的关联分析 I. 群体结构及关联标记

关联作图是一种利用连锁不平衡(linkage disequilibrium, LD)检测自然群体中基因位点及其等位变异的方法。利用60个SSR标记, 对全国大豆地方品种群体(393份代表性材料)和野生大豆群体(196份代表性材料)的基因组变异进行扫描, 分析两类群体的连锁不平衡位点、群体结构, 并采用TASSEL软件的GLM (general linear model)方法对16个农艺、品质性状观测值进行标记与性状的关联分析。结果表明: (1)在公共图谱上不论共线性的或是非共线性的SSR位点组合都有一定程度的LD, 说明历史上发生过连锁群间的重组; 栽培群体的连锁不平衡成对位点数较野生群体多, 但野生群体位点间连锁不平衡程度高, 随距离的衰减慢。(2) 群体SSR数据遗传结构分析发现, 栽培群体和野生群体分别由9和4个亚群体组成, 亚群的划分与群体地理生态类型相关联, 证实地理生态类型划分有其遗传基础。(3) 栽培群体中累计有27个位点与性状相关; 野生大豆种质中累计有34个位点与性状相关。部分标记在两类群体中都表现与同一性状关联, 检出的位点有一致性, 也有互补性; 一些标记同时与2个或多个性状相关联, 可能是性状相关乃至一因多效的遗传基础; 关联位点中累计有24位点(次)与遗传群体连锁分析定位的QTL一致。