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Notes: Abstract A secondary periodicity in variation of the properties of ferroelectric solid solutions of lead titanate with rare-earth metals is established. It is demonstrated that this behavior is related both to the modifying cations belonging to two natural subgroups and to the energetic features of their 4f levels. The extrema of the structural and ferroelectric characteristics correspond to the domains of electron instability.

Notes: Abstract We study the linear response of a system of single-domain ferromagnetic particles with cubic magnetic anisotropy to a weak external a.c. magnetic field. By averaging the Gilbert equation with a fluctuating field for the magnetization of an individual particle we derive a system of recurrence equations for the spectra of equilibrium correlation functions describing the longitudinal relaxation of the system. We find the solution of this system by using matrix continued fractions. We also evaluate the longitudinal relaxation time and the spectrum of the complex-valued magnetic susceptibility. Finally, we show that the nature of susceptibility dispersion is determined by the anisotropy and dissipation parameters.

Notes: Abstract The formation and development of bulk crystallochemical defects—mesoscopic clusters representing the nuclei of new phases—was studied in systems exhibiting concentration phase transitions. When a solid solution approaches a morphotropic region, the clusters exhibit a stepwise evolution involving several stages manifested by corresponding changes in macroscopic properties. The role of clusters in the development of the extreme electrophysical properties of the objects studied is discussed.

Notes: Abstract The dynamic susceptibility spectrum of single-domain particles with cubic anisotropy has been calculated within the continuous diffusion model throughout the total range of anisotropy-and damping-parameter variation.

Notes: Abstract The magnetic relaxation of a system of single-domain ferromagnetic particles in the presence of a strong static magnetic field directed at an arbitrary angle relative to the particle anisotropy axis is investigated. A system of linear difference-differential equations for the moments (averaged spherical harmonics) is derived without recourse to the Fokker-Planck equation by averaging Gilbert’s equations with a fluctuating field. An exact solution (in terms of matrix continuous fractions) is found for this system. The relaxation times and spectra of the complex magnetic susceptibility are calculated.

Notes: Abstract A system of equations is derived for moments [averages of spherical harmonics 〈Y l,m 〉(t)] that determine the dynamics of the magnetization M of a superparamagnetic particle in a fluctuating field. The system is derived by representing the Gilbert equation in a fluctuating field, and the corresponding Fokker-Planck equation for the distribution function of M, in terms of angular momentum operators, which in turn makes it possible to express the coefficients of the system of moment equations in terms of Clebsch-Gordan coefficients.

Notes: Abstract For a system of superparamagnetic particles in a high external constant magnetic field, a technique for calculating the nonlinear response to a sudden change in the field direction and magnitude is proposed. A set of momentary equations for the averaged spherical harmonics, which is derived from the Fokker-Planck equation for the magnetization-orientation distribution function is the basis of this technique. As an example, the nonlinear response of a system of particles with anisotropy of the easy-axis type is examined. For this case, a solution to the momentary equations is obtained by using matrix continued fractions. The magnetization relaxation time and the spectrum of the relaxation function are calculated for typical values of anisotropy, dissipation, and nonlinearity parameters. It is shown that the magnetization kinetics is essentially dependent on these parameters.

Notes: Abstract. The results of population genetics studies associated with the problem of the restoration of Atlantic salmon, Salmo salar L., in Russia are presented. The peculiarities of using donor material for artificial population formation when the native gene pool has been lost are discussed. Genetic polymorphism in 19 salmon populations from different areas (within Russia) were investigated and analysed. Intrapopulation genetic differences of the Pechora River Atlantic salmon are shown. The role of monitoring in salmon culture is discussed and the results of an ecologo-genetic evaluation of natural and artificial salmon populations are presented.

Notes: Electrophoretic studies of proteins remain a primary source of insight into genetic diversity in many species including the Atlantic salmon Salmo salar, one of the most culturally and economically important fish species of the North Atlantic region. Since 1966, 〉350 scientific papers on protein variation have been published encompassing 25 000+ salmon from over 400 locations in 〉200 river systems across the species’ distribution. Variation has been detected at 30% of the 110 protein loci screened, though most studies examine 〈40. The method has been applied largely to the investigation of population structure and differentiation, but work has also led to the systematic revision of the genus Salmo and remains the primary source of insight into hybridization in the wild with brown trout Salmo trutta. Spatial patterns of differentiation show temporal stability, both within and among river systems, and strongly support structuring of the species into river and tributary specific populations and the designation of European and North American populations as distinct sub-species. They also show widespread regional differentiation within both continents, beyond the marked subcontinental differences between Baltic Sea and Atlantic Ocean populations in Europe. Most of the differentiation probably reflects gene flow and founder events associated with colonization following the retreat of the glaciers from much of the species’ modern range. However, variation at MEP-2* shows strong correlations with environmental temperature, both within and among rivers, and associations with phenotypic performance. This suggests selection is acting on the locus and provides compelling evidence for the local adaptation of populations. Protein studies have led to more population centred management of the species and have been exploited in the discrimination of regional stocks in mixed stock analysis in high seas fisheries, particularly in the Baltic Sea, and as markers for the assessment of stocking success. They have also advanced insight into how the genetic character of populations can be changed in cultivation and the potential impact of salmon aquaculture and stocking on wild populations. The method has been largely superseded by DNA based analyses, but the results remain highly relevant to Atlantic salmon management and conservation and are an irreplaceable data set for studying genetic stability of populations over time.

Notes: The results of rearing salmon smolts, using warm water in winter time, are presented. Fishes weighing 25–50 g were released in spring time at the age of about 1 year, while smaller fishes were left to grow in ponds for release at age 2 years. As a result of warm-water wintering of fingerlings, the yield to the fishery was at least doubled, while there was no decrease in fish size, nor in gamete quality. Three thousand to 5000 spawners entered the Narova River (Baltic Sea) per annum and the trend is to exceed these totals.