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151.
WOMBAT A tool for mixed model analyses in quantitative genetics by restricted maximum likelihood (REML) 总被引:31,自引:0,他引:31
Meyer K 《Journal of Zhejiang University. Science. B》2007,8(11):815-821
WOMBAT is a software package for quantitative genetic analyses of continuous traits, fitting a linear, mixed model; estimates of covariance components and the resulting genetic parameters are obtained by restricted maximum likelihood. A wide range of models, comprising numerous traits, multiple fixed and random effects, selected genetic covariance structures, random regression models and reduced rank estimation are accommodated. WOMBAT employs up-to-date numerical and computational methods. Together with the use of efficient compilers, this generates fast executable programs, suitable for large scale analyses. Use of WOMBAT is illustrated for a bivariate analysis. The package consists of the executable program, available for LINUX and WINDOWS environments, manual and a set of worked example, and can be downloaded free of charge from http://agbu. une.edu.au/~kmeyer/wombat.html 相似文献
152.
153.
Genetic analysis of fruit shape traits at different maturation stages in sponge gourd 总被引:5,自引:0,他引:5
The fruit shape is important quantitative trait closely related to the fruit quality. However, the genetic model of fruit shapes has not been proposed. Therefore, in the present study, analysis of genetic effects for fruit shape traits (fruit length and fruit perimeter) in sponge gourd was conducted by employing a developmental genetic model including fruit direct effects and maternal effects. Analysis approaches of unconditional and conditional variances were applied to evaluate the genetic behavior of fruit shape traits at economical and physiological maturation times. The results of variance analysis indicated that fruit length and fruit perimeter were simultaneously affected by fruit direct genetic effects and maternal effects. Fruit direct genetic effects were relatively more important for fruit shape traits at whole developmental period. The gene expression was most active at the economical maturation stage (1-12 d after flowering) for two shape traits, and the activation of gene was mostly due to direct dominance effects at physiological maturation stage (13-60 datter flowering). The coefficients due to different genetic effects, as well as the phenotypic correlation coefficients, varied significantly between fruit shape traits themselves at various maturation stages. The results showed that it was relatively easy to improve fruit shape traits for industrial purpose by carefully selecting the parents at economical maturation stage instead of that at physiological maturation stage. 相似文献
154.
The yeast strain (Y18) was isolated from a soil sample collected from Fildes Peninsula, Antarctica. The strain is a psychrophilic yeast with optimum and maximum growth temperatures of 10 ℃ and 18 ℃, respectively. Teliospores were formed after 7 d on malt agar, when the germination of teliospores was observed. Both inositol and D-glucuronate were assimilated. Positive results of the DBB (diazonium blue B) color reaction, urease test, and starch formation were observed. The major CoQ is Qs. All results indicated that Y18 belongs to the genes of Mrakia. The 18S rDNA sequence analyses showed that Y18 is closely related to Mrakiafrigida. DNA-DNA relatedness study, and some biochemistry characteristics indicated that Y18 represents a new species for which Mrakia psychrophila sp. nov. is proposed. 相似文献
155.
Phonological awareness, phonological memory, and phonological access to lexical storage play important roles in acquiring
literacy. We examined the convergent, discriminant, and predictive validity of these phonological processing abilities (PPA)
in 389 3-, 4-, and 5-year-old children. Confirmatory factor analysis supported the validity of each PPA as separate from general
cognitive ability and separate from each other. Multigroup structural equation modeling (SEM) with mean structure demonstrated
that older preschoolers have better developed latent PPA than younger preschoolers but that the structure of PPA is equivalent.
RAN was found uniquely associated with letter knowledge and text discrimination in younger preschoolers, and PA was found
uniquely associated with word reading skills in older preschoolers. Finally, general cognitive ability was only indirectly
associated with emergent literacy via PPA. These results highlight the importance of PPA in the early literacy development
of English-speaking preschool children. 相似文献
156.
Considering the uncertainty of material performance, geometric characteristic and analysis method, the analysis of statistical parameters of the resistance of cast ball-and-socket support joints and the reliability analysis are carried out by JC method (improved first-order second-moment method) based on the relevant experimental data. Results show that the resistance partial factor of the joint increases with the increase of the reliability index. The resistance partial factors are suggested corresponding to the reliability index under different load combinations. Moreover, the suggested resistance partial factor is adopted in reliability design, and it is found that the reliability index of the joint is larger than the target reliability index. The optimal load combination is the one in which live load plays an important control role. Finally, based on the suggested resistance partial factors, the reliability analysis of cast ball-and-socket support joints of a project is conducted. 相似文献
157.
158.
Funding agencies in Canada are attempting to break down the organizational boundaries between disciplines to promote interdisciplinary
research and foster the integration of the social sciences into the health research field. This paper explores the extent
to which biomedical and clinician scientists’ perceptions of social science research operate as a cultural boundary to the
inclusion of social scientists into this field. Results indicated that cultural boundaries may impede social scientists’ entry
into the health research field through three modalities: (1) biomedical and clinician scientists’ unfavourable and ambivalent
posture towards social science research; (2) their opposition to a resource increase for the social sciences; and (3) clinician
scientists procedural assessment criteria for social science. The paper also discusses the merits and limitations of Tom Gieryn’s
concept of boundary-work for studying social dynamics within the field of science.
相似文献
Brian D. HodgesEmail: |
159.
Rethinking Polanyi’s Concept of Tacit Knowledge: From Personal Knowing to Imagined Institutions 总被引:1,自引:0,他引:1
Half a century after Michael Polanyi conceptualised ‘the tacit component’ in personal knowing, management studies has reinvented
‘tacit knowledge’—albeit in ways that squander the advantages of Polanyi’s insights and ignore his faith in ‘spiritual reality’.
While tacit knowing challenged the absurdities of sheer objectivity, expressed in a ‘perfect language’, it fused rational knowing, based on personal experience, with mystical speculation about an un-experienced ‘external reality’. Faith alone saved Polanyi’s model from solipsism. But Ernst von Glasersfeld’s
radical constructivism provides scope to rethink personal tacit knowing with regard to ‘other people’ and the intersubjectively
viable construction of ‘experiential reality’. By separating tacit knowing from Polanyi’s metaphysical realism and drawing
on Benedict Anderson’s concept of ‘imagined communities’, it is possible to conceptualise ‘imagined institutions’ as the tacit
dimension of power that shapes human interaction. Whereas Douglass North claimed institutions could be reduced to rules, imagined
institutions are known in ways we cannot tell. 相似文献
160.
This article investigates the effect of a Tony nomination or win on the demand facing a Broadway production using a panel
of weekly revenues for Broadway productions from 1996 to 2007. Our results indicate that the effect of a nomination or win
is positive in the week of the announcement and gradually increases in successive weeks, presumably due to publicity and word-of-mouth.
Winners experience an increase in demand as late as 1 year later when awards are publicized for the following season. Moreover,
nominees that do not win the award are penalized heavily in the weeks following the Award announcements. We find that winning
a Tony Award increases a production’s revenues by 12% in the week immediately following the Awards.
相似文献
Lesley ChiouEmail: |