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Abstract: The morphology of nanostructures, which were grown on the (0001) van der Waals surface of layered GaSe crystals and annealed under thermodynamically equilibrium conditions at high pressures of sulfur vapor, has been investigated using atomic force microscopy. The morphology and phase composition of the nanostructures are determined by the deformation and chemical interactions between the vapor phase and the crystal surface and by the thermodynamic conditions of annealing. Elements of nanostructures are formed as small Ga2S3 nanocrystallites, pyramidal quantum dots, and quantum rings on the defective (0001) van der Waals surface that contains nanosized indentations (nanocavities) and liquid gallium.

According to current concepts, memory can be disrupted by administration of protein synthesis inhibitors over a relatively short time period before and after learning. However, data have been obtained indicating that protein synthesis inhibitors can induce amnesia when given long after learning if administration is performed in reminder conditions, i.e., when the animal is presented with one of the environmental components which previously formed the learning situation. The aim of the present work was to confirm the possibility of inducing memory disruption in chicks at late post–learning stages by administering the protein synthesis inhibitor cycloheximide in association with a reminder procedure. Day–old chicks were trained to perform a standard passive avoidance task. Chicks were given cycloheximide (20 μg, intracerebrally) 5 min before the reminder procedure, which was performed 2, 24, or 48 h after training. Testing was conducted 0.5, 1, 3, 24, and 48 h after the reminder. Administration of cycloheximide in association with the reminder procedure induced the development of temporary amnesia, whose duration gradually decreased as the interval between training and reminding increased. These data led to the hypothesis that a memory reactivated by a reminder undergoes a process of reorganization and reconsolidation, which depends on the synthesis of new proteins. The quenching of the ability of protein synthesis inhibition during the reminder to disrupt memory demonstrates the existence of a gradual process resulting in consolidation of memory between 2 and 48 h of learning.

A finite-element technique has been used in solving a boundary-value problem for a two-dimensional npnstationary turbulent-diffusion equation.

Abstract: The problem of reducing the number of initial data for the earth surface in an algorithm of automatic control is investigated. Bibliography: 9 titles.

A general algorithm is proposed for constructing interlineation operators , x=(x1, x2) with the properties

An algorithm for constructing the operator OMn({?kx}; x, y) with the properties $$\begin{gathered} O_{Mn} (\{ \varphi _{ks} \} ;x,y) \in C^r (R^2 \backslash G), G = \{ \Gamma _k \cap \Gamma _l ;k, l = 1, M;k \ne l\} , r > n, \hfill \\ \frac{{\partial ^n O_{Mn} (\{ \varphi _{ks} \} ;x,y)}}{{\partial v_a^p }}|_{\Gamma _a } = \varphi _{ap} (x,y)|_{\Gamma _Q '} q = \overline {1, M} ; p = \overline {0, n,} \hfill \\ \end{gathered} $$ , is proposed for the first time; here {?g} is a given family of straight lines of an arbitrary location, ?q is a normal to ?q, ?qqp(x, y) ? Cr-P(R2), $$p = \overline {0, n,} $$ , are given functions. An integral analog of the generalized D'Alembert formula, which utilizes averaging certain repeated integrals of traces rather than the traces themselves, serves as the basis for this paper. An integral representation of the remainder of approximating functions u(x, y) ? Cr(R2) with properties by the operators OMn({?ks}; x, y).