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The genetic parameters of donor and artificial populations of Siberian salmon (Oncorhynchus keta) have been analyzed. The parameters were obtained with the use of different molecular markers as well as mathematic modeling based on experimental data. The difference between results is explained by the different resolving power of individual markers and/or stochastic effects. It is assumed that these factors together with temporal differentiation of spawning salmonid populations and the stable interpopulation gene flow constrain resolution of methods based on the use of molecular markers and designated for the analysis of differentiation of salmonid populations.

We used Bayesian statistics to investigate the demographic history of the walleye pollock in the sea of Okhotks based on polymorphisms of sequences of the Nd2 and Cytb mitochondrial genes. We determined the average age for the Most Recent Common Ancestor (MRCA) as 44.1 ± 2 and 52.6 ± 1.3 thousand years, respectively, for Nd2 and Cytb. These findings suggest that demographic expansion of the Okhotsk Sea pollock began 10–12 thousand years ago, which coincides with the period of global changes in the sea level during the Late Pleistocene-Early Holocene eras.

Eleven samples of Pacific herring from the four seas of Eurasia (Sea of Japan, Sea of Okhotsk, Bering Sea, and White Sea), and one sample of Atlantic herring were analyzed. Complete and partial sequences of the mtDNA control region with the sizes up to 1071 bp were used. To verify the haplogroups identified, additional sequencing of the cytochrome oxidase I gene was performed. It was demonstrated that Pacific herring from the seas of Eurasia belonged to one mitochondrial haplogroup. The gene flow between the localities from different parts of the Far Eastern sea basins was about 11% per locality, per generation, which led to constant leveling of herring intraspecific differentiation. The data presented gave no reasons for subdivision of the herring populations in accordance to ecological characters (lacustrine and marine). Analysis of global molecular variance (global AMOVA) demonstrated that in Asian water basins, more than 98% of molecular polymorphism was found within the samples at the low level of significance (P < 0.05).

The solar neutrino capture rate measured by SAGE is well below that predicted by solar models. To check the overall experimental efficiency, we exposed 13tonnes of Ga metal to a reactor-produced 517kCi source of {sup 51}Cr. The ratio of the measured production rate to that predicted from the source activity is 0.95{plus_minus}0.11(stat)+0.05/{minus}0.08(syst). This agreement verifies that the experimental efficiency is measured correctly, establishes that there are no unknown systematic errors at the 10{percent} level, and provides considerable evidence for the reliability of the solar neutrino measurement. {copyright} {ital 1996 The American Physical Society.}

This paper deals with regularities of the phonon thermal conductivity variations depending upon the mean molecular weight of chalcogenides of the Ist, IVth and Vth groups of the periodic system. The obtained relations in the form of X L = A. M a are explained according to Blackman and Keyes.