Mode-analytical Examination of Vortex Dynamics of a Pure Electron Plasma in the Relaxation to a Meta-equilibrium Distribution

On using five hypothetical systems differing in the extent of mutual solubility of components, tie-line slope, and type of binodal curve, the effect is evaluated of systematic errors in the form of absolute deviation in the liquid-liquid equilibrium distribution concentrations on the accuracy of calculated number of theoretical stages of isothermal countercurrent extraction under various operating conditions.

Download Full-text

Analysis of Genetic Structure and Dispersal Patterns in a Population of Sea Beet

Genetics ◽

10.1093/genetics/149.4.1975 ◽

1998 ◽

Vol 149 (4) ◽

pp. 1975-1985

Author(s):

Jarle Tufto ◽

Alan F Raybould ◽

Kjetil Hindar ◽

Steinar Engen

Keyword(s):

Equilibrium Distribution ◽

Pollen Dispersal ◽

Migration Pattern ◽

Likelihood Ratio Tests ◽

Frequency Data ◽

Gene Frequencies ◽

Dispersal Patterns ◽

Parametric Bootstrapping ◽

Estimated Parameters ◽

Multivariate Stochastic Process

Abstract A model of the migration pattern in a metapopulation of sea beet (Beta vulgaris L. ssp. maritima), based on the continuous distributions of seed and pollen movements, is fitted to gene frequency data at 12 isozyme and RFLP loci by maximum likelihood by using an approximation of the simultaneous equilibrium distribution of the gene frequencies generated by the underlying multivariate stochastic process of genetic drift in the population. Several alternative restrictions of the general model are fitted to the data, including the island model, a model of complete isolation, and a model in which the seed and pollen dispersal variances are equal. Several likelihood ratio tests between these alternatives are performed, and median bias in the estimated parameters is corrected by using parametric bootstrapping. To assess the fit of the selected model, the predicted covariances are compared with covariances computed from the data directly. The dependency of estimated parameters on the ratio between effective and absolute subpopulation sizes, which is treated as a known parameter in the analysis, is also examined. Finally, we note that the data also appear to contain some information about this ratio.

Download Full-text