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Fluid inclusions in minerals from more than 22 Au-Hg deposits (Central Asia, Urals, East Sayan, Gorny Altai, northeastern Russia, Mongolia, etc.) have been examined by thermobarogeochemical methods (thermo- and cryometry, Raman spectroscopy of gas phase). It has been established that Au-Hg deposits are low-temperature (280-50 ^oC) hydrothermal objects which formed in subsurface (volcanogenic-hydrothermal) or shallow-depth (plutonogenic-hydrothermal) conditions, under pressures lower than 500-600 bars. The volcanogenic-hydrothermal Au-Hg deposits were formed with participation of weakly concentrated (10-0.5, less frequently to 14 wt.%) chloride or chloride-bicarbonate-sodium hydrothermal fluids with low-density N₂-CO₂ (CH₄) gas phase. The ore-forming fluids of plutonogenic-hydrothermal deposits are characterized by wider variations in concentration (from 0.2 to 25 wt.%), complex salt composition (NaCl, CaCl₂, FeCl₂, KCl, etc.), and dense highly CO₂ gas phase (CO₂ N₂ CH₂); in salt composition and reduced character they similar to magmatic fluids. The characteristic feature of the fluid regime of ore-forming systems of volcanogenic- and plutonogenic-hydrothermal Au-Hg deposits is the heterogenous state of ore-forming fluids. In particular ore districts, the physicochemical parameters of formation of volcanogenic- and plutonogenic-hydrothermal Au-Hg deposits are generally close to the parameters of formation of similar Au-Sb, Sb and Sb-Hg deposits. The results obtained from the thermobarogeochemical study stress the polygene nature of Au-Hg deposits.

The paper studies boundary‐value problems for dynamic-diffusion boundary layers occurring near a vertical wall at high Schmidt numbers and for dynamic boundary layers whose inner edge is adjacent to the dynamic-diffusion layers. Exact solutions for boundary layers at small and large times are derived. The well-posedness of the boundary-value problem for a steady dynamic-diffusion layer is studied.

The stability of the equilibrium state of a flat layer bounded by rigid walls is studied using a microconvection model. The behavior of the complex decrement for long-wave perturbations has an asymptotic character. Calculations of the full spectral problem were performed for melted silicon. Unlike in the classical Oberbeck–Boussinesq model, the perturbations in the microconvection model are not monotonic. It is shown that for small Boussinesq parameters, the spectrum of this problem approximates the spectra of the corresponding problems for a heat- conducting viscous fluid or thermal gravitational convection when the Rayleigh number is finite.

According to theory, animals should attempt to optimize the allocation of resources among the competing demands for reproduction, growth, survival, and of course maintenance, so as to maximize lifetime reproductive output. Trade-offs between immune competence and other life-history attributes have received much of this research interest because of the potential returns to our understanding of population processes in a changing environment.
The main modern hypotheses about ecological factors and evolutionary reasons of wide range variability of immunocompetence in population of animals are reviewed in this paper.