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The results of comprehensive studies of structural and phase transformations in (K0.43(NH4)0.57)3H(SO4)2 superprotonic crystals under the influence of atmospheric moisture are presented. The real structure, composition, and thickness of the modified surface layers have been analyzed using scanning electron microscopy and X-ray microscopy. The local characteristics of nanostructures, formed on the freshly cleaved (001) crystal surface subjected to the electrostatic effect, have been investigated by conductive atomic force microscopy. A correlation has been established between the time changes in the structure, composition, and magnitude of the electrostatic potential of the crystal surface. The results are considered in the context of evaluation of the chemical stability of the samples and searching for the ways to optimize the compositions and functional properties of superprotonic compounds. [ABSTRACT FROM AUTHOR]

The health of a population is an important indicator of the general well-being of the population, and it has its practical significance, as it determines the costs of providing care, and social and medical assistance for the elderly. The study presents an assessment of healthy life-expectancy indicators of people over age 65 based on the results of the Russian epidemiological study EVCALIPT and a comparison of this results with data from other surveys in Russia and European countries. [ABSTRACT FROM AUTHOR]

The phase equilibria in the K2SO4–Rb2SO4–H2SO4–H2O system have been investigated under isothermal conditions at 25°C. The concentration limits of crystallization of solid solutions with the general formulas (KxRb1–x)2SO4, (KxRb1–x)3H(SO4)2, (KxRb1–x)9H7(SO4)8 ⋅ H2O, and KxRb1–xHSO4 and the K0.55Rb0.45HSO4 phases are determined. The dependences of the equilibria of saturated solutions on the initial production conditions are revealed. The growth conditions for large single crystals of complex acid potassium–rubidium sulfates are determined. The phase-equilibrium diagram of the system is constructed. [ABSTRACT FROM AUTHOR]

Single crystals of (K1‒x(NH4)x)3H(SO4)2 (x ≥ 0.57) solid solutions have been studied by electrical atomic force microscopy. At 296 K, the local current–voltage characteristics of trigonal superprotonic phases were measured for the samples with different concentrations of K and NH4 cations as a function of the c axis orientation, and anisotropy of conductivity was established. The degree of the dependence of the conduction properties on the composition is determined. The temporal changes in the morphology, potential, and surface capacitance derivatives of the (001) (K0.43(NH4)0.57)3H(SO4)2 surface were traced and evaluated when the samples were held in air under conditions of constant humidity and temperature. [ABSTRACT FROM AUTHOR]

Hydrogen bonds are one of the most enigmatic intermolecular interactions where the strength of interaction depends very intimately on the local environment of the bonded atoms. One can change the entire nature of the interactions by changing its local environment. Many of the enzymatic reactions work by this above-mentioned mechanism. Hence, it is important to understand how changes in the local environment can modify hydrogen bonds. In line with this, complete structural and vibrational investigations on ammonium ion substituted potassium dihydrogen phosphate mixed crystals K0.988(NH4)0.012H2PO4 and (K0.956(NH4)0.044H2PO4) are performed. The behaviour of O–H–O hydrogen bond in these crystals is very sensitive to changes in the local environment. A small change in the concentration of K+ ion has an observable effect on hydrogen bond geometry and hence on the double-well potential energy contour for these bonds. The dynamics of H atom depends on the potential barrier height. It changes gradually with decreasing temperature from predominantly inter-well to completely intra-well dynamics with an intermediate precursor region, where inter-well and intra-well dynamics are important. [ABSTRACT FROM AUTHOR]

Superprotonic (NH4)3H(SeO4)2 crystals in the ferroelastic phase are studied via optical polarization microscopy and atomic force microscopy to obtain data on their true structure. Twinned structures on cleavages parallel and perpendicular to the (001) plane of the high-temperature paraelastic phase and their correlation with the atomic structure of crystals are considered. [ABSTRACT FROM AUTHOR]

Single-crystal neutron diffraction investigation on Cs4(HSO4)3(H2PO4) and Cs6H(HSO4)3(H2PO4)4 superprotonic crystals, belonging to CsHSO4–CsH2PO4–H2O salt system, is under taken to elucidate the precise hydrogen atom positions in these crystals. The investigation revealed that these crystals are very sensitive to the ambient conditions and can undergo deterioration due to fluctuation in air moisture content. Cs6H(HSO4)3(H2PO4)4 crystals are more stable as compared to Cs4(HSO4)3(H2PO4). Crystal structure of Cs6H(HSO4)3(H2PO4)4 is obtained both before and after deterioration, it is found that the asymmetric O–HO hydrogen bond between the PO4 and SO4 ions of this crystal becomes stronger after deterioration. This led to the shrinkage of the unit cell, and most likely prevented further deterioration. Diabatic state model for hydrogen bonds is used to obtain the energy contour for the O–H···O hydrogen bond of Cs6H(HSO4)3(H2PO4)4 crystal. The influence of this change in the hydrogen bonding on the proton conduction ability of the crystal is discussed. [ABSTRACT FROM AUTHOR]

The (NH4)3H(SeO4)2 crystals in the temperature range of 296–343 K and the evolution of their surface at phase transitions have been studied by atomic force microscopy. Data on morphology and local electrical characteristics of crystal surface are obtained. Local current–voltage characteristics are measured, and the existence of structural phase transition to the phase with superprotonic conductivity at T ≈ 308 K is confirmed. A layer of non-conducting phase of variable composition is shown to appear on the crystal surface at the phase transitions. [ABSTRACT FROM AUTHOR]

New data are presented on tornadoes over land in Russia for the period of 1900–2018 based on various sources. In total, information on 1763 tornadoes was collected, including 993 tornadoes from eyewitness reports on tornado passage and/or associated impacts and 770 tornadoes from satellite data on tornado-induced windthrows. Both single tornadoes and tornado outbreaks, the cases of formation of several tornadoes within one meso- or synoptic-scale system, were reported. On average for 2009–2018, more than 100 tornadoes are observed in Russia per year, including 15 significant tornadoes (with a wind speed m/s) and one intense tornado (with a wind speed m/s). In some years, these rates can be significantly higher and reach 342, 52, and three tornadoes per year, respectively. Tornadoes are observed on about 41 days per year, up to 68 days per annum in some years. The frequency of occurrence of tornadoes of different categories and the probability of their passage over a point on the ground were estimated. These estimates can be further used to assess a risk of tornado-hazardous situations. The general underestimation of the number of tornadic events in routine meteorological observations and existent statistics is discussed. [ABSTRACT FROM AUTHOR]

An investigation of new superprotonic crystals—namely, acid salts of potassium–ammonium sulfate (K1 –x(NH4)x)3H(SO4)2, x ≥ 0.57—is carried out. The surface morphology, domain structure, and conductivity of the samples are studied using atomic force microscopy. The stability and degradation of the surface of superprotonic crystals is first studied at the nanoscale. The data of piezoelectric response microscopy make it possible to establish that the crystal of (K0.43(NH4)0.57)3H(SO4)2 transits from the paraelectric phase to the ferroelectric phase when the temperature is decreased from 296 K to 282 K. [ABSTRACT FROM AUTHOR]

The phase equilibria in the CsHSO4–CsH2PO4–NH4H2PO4–H2O four-component aqueous salt system have been studied. The crystallization ranges and solubilities have been determined for the CsHSO4, NH4H2PO4, and (Cs,NH4)H2PO4 phases and the phases obtained for the first time: (Cs,NH4)4(HSO4)3(H2PO4) and (Cs,NH4)2(HSO4)(H2PO4). Cs3NH4(HSO4)3(H2PO4) and CsNH4(HSO4)(H2PO4) crystals of stoichiometric composition have also been grown for the first time. [ABSTRACT FROM AUTHOR]

Surfaces of the natural cleavage of water-soluble single crystals (K0.43(NH4)0.57)3H(SO4)2 is studied via atomic force microscopy. It is shown that ultrafine details of nanorelief (pits and hills with stable parameters of height (depth) of ~0.7 nm form on the surfaces of crystals) correspond to 1/3 с in a unit cell. A phase transition (from paraelectric to ferroelectric) is detected in the (K0.43(NH4)0.57)3H(SO4)2 crystal via microscopy of the piezoelectric response as the temperature falls from 296 to 282 K. [ABSTRACT FROM AUTHOR]

The phase equilibria in the CsHSO4–CsH2PO4–NH4H2PO4–H2O four-component aqueous salt system have been studied. The crystallization ranges and solubilities have been determined for the CsHSO4, NH4H2PO4, and (Cs,NH4)H2PO4 phases and the phases obtained for the first time: (Cs,NH4)4(HSO4)3(H2PO4) and (Cs,NH4)2(HSO4)(H2PO4). Cs3NH4(HSO4)3(H2PO4) and CsNH4(HSO4)(H2PO4) crystals of stoichiometric composition have also been grown for the first time. [ABSTRACT FROM AUTHOR]

The dielectric spectroscopy method was used to study the dielectric properties and conductivity of superprotonic single crystals (Kx(NH4)1−x)3H(SO4)2 (x = 0.19, 0.27, 0.43)in the 0.1 Hz–10 MHz frequency range and the 223–353 K temperature interval. An analysis of experimental data was carried out using the formalisms of AC conductivity and the electric modulus. The room temperature value of DC conductivity of the studied crystals obtained from solid solutions was approximately ∼10−5 (Ω · cm)−1, which corresponds to the conductivity values of the initial compounds at high temperatures. The comparable values of the activation energy of both DC conductivity and modulus spectrum suggest that protons are involved not only in the conductivity, but also in the process of electric relaxation. Modulus analysis indicated the temperature independent distribution of relaxation times and the non-Debye behavior in these materials. The temperature dependence of DC conductivity exhibits three (for x = 0.l9 and 0.27) and two (for x = 0.43) temperature intervals with different activation energies, which indicates the presence of structural transitions that cause a change in the mechanism of proton transport. [ABSTRACT FROM AUTHOR]

The phase equilibria in the K3H(SO4)2–Rb3H(SO4)2–H2O cross section have been investigated under isothermal conditions at 25°C. The concentration limits of crystallization of solid solutions with the general formulas (Rb1 –xKx)3H(SO4)2 and (Rb1 –xKx)2SO4 are determined. The dependences of the equilibria of saturated solution on the initial production conditions are revealed. The growth conditions for large single crystals of complex acid rubidium–potassium sulfates are determined. [ABSTRACT FROM AUTHOR]

One of the most rapidly developing directions in the field of alternative energy sources is hydrogen energetics. Fuel cells, the main component of which is a proton-exchange membrane, facilitate the direct conversion of chemical energy into electrical energy. Superprotonic crystals are promising materials for the creation of proton-exchange membranes of fuel cells and other electrochemical. Multicomponent water–salt growth systems are studied in order to obtain new superprotonic crystals MmHn(AO4)(m+n)/2 ⋅ yH2O (M = K, Rb, Cs, NH4, AO4 = SO4, SeO4, HPO4) and modify the properties of known compounds. The conditions for the growth of a number of new superprotonics are found, and the relationships between their structure and properties are studied. [ABSTRACT FROM AUTHOR]

Abstract: The phase equilibria in the quaternary water-salt system Cs2SO4-Rb2SO4-H2SO4-H2O have been studied. The crystallization ranges are determined, and single crystals of (Cs1 - xRbx)2SO4 and Cs1 - xRbxHSO4 solid solutions have been grown. The (Cs1 - xRbx)3H(SO4)2 and (Cs1 - xRbx)5H3(SO4)4 · yH2O compounds are obtained for the first time. [ABSTRACT FROM AUTHOR]

The structure of (K1-x(NH4)x)3H(SO4)2 crystals with a low ammonium concentration and the behavior of their thermal, optical, and dielectric properties in a temperature range of 275-500 K have been investigated to clarify the influence of doping on the phase transition kinetics. An examination of unit-cell parameters of (K1 - x(NH4)x)3H(SO4)2 single crystals has confirmed the existence of a superprotonic phase transition at a temperature of ≈450K. The conducting properties of single-crystal and polycrystalline samples have been studied. [ABSTRACT FROM AUTHOR]

The structure of (K0.967(NH4)0.033)3H(SO4)2 crystals, belonging to the K3H(SO4)2-(NH4)3H(SO4)2-H2O salt system, has been investigated by X-ray structural analysis. The room-temperature characteristics of the atomic structure of these crystals are found to be as follows: sp. gr. C2/c, Z = 4, a = 14.7025(4) Å, b = 5.6859(2) Å, c = 9.7885(3) Å, and R/wR = 0.021/0.030%. The thermal and optical properties of (K,NH4)3H(SO4)2 and K3H(SO4)2 single crystals have been investigated and compared in a temperature range of 295-500 K. [ABSTRACT FROM AUTHOR]

The structure of the mixed crystal [K1− x(NH4) x]3H(SO4)2 as obtained from single-crystal neutron diffraction is compared with the previously reported room-temperature neutron structure of crystalline K3H(SO4)2. The two structures are very similar, as indicated by the high value of their isostructurality index (94.8%). It was found that the replacement of even a small amount (3%) of K+ with NH4+ has a significant influence on the short strong hydrogen bond connecting the two SO42− ions. Earlier optical measurements had revealed that the kinetics of the superionic transition in the solid solution [K1− x(NH4) x]3H(SO4)2 are much faster than in K3H(SO4)2; this reported difference in the kinetics of the superionic phase transition in this class of crystal is explained on the basis of the difference in strength of the hydrogen-bond interactions in the two structures. [ABSTRACT FROM AUTHOR]

To reveal the effect of isomorphic substitution on the kinetics of phase transitions, single crystals of (K(NH))mH(SO) · yHO solid solutions are grown from the KH(SO)-(NH)H(SO)-HO system. The chemical composition of the single crystals grown is determined by energy dispersive X-ray microanalysis. The thermal, optical and dielectric properties of (K(NH))H(SO) · yHO single crystals are studied. The structural conditionality of the physical properties of these compounds is determined on the basis of the data of precision studies of the structure. [ABSTRACT FROM AUTHOR]

CsH(HSO)(HPO) crystals, grown for the first time based on an analysis of the phase diagram of the CsHSO-CsHPO-HO ternary system, have been investigated by structural analysis using synchrotron radiation. The atomic structure of the crystals is determined and its specific features are analyzed. [ABSTRACT FROM AUTHOR]

The solubility in the CsHPO-CsHSO-HO system at different temperatures (25, 50, and 75°C) is studied and the phase equilibria in the RbH(SO)-RbHPO-HO system under isothermal conditions (at 25°C) are analyzed. The temperature and concentration conditions for forming Rb(HSO)(HPO), Rb(HSO)(HPO), Cs(HSO)(HPO), Cs(HSO)(HPO), Cs(HSO)(HPO), and CsH(HSO)(HPO) compounds (the latter has been obtained for the first time) are determined. The conditions for growing large single crystals of complex acid rubidium and cesium salts are found. [ABSTRACT FROM AUTHOR]

Results of a study of variations in optical parameters of bioindicators that grow in the regions of hydrogen degassing in Samara are presented. Raman spectroscopy and confocal fluorescence microscopy were used as the main methods of the study. Features of Raman spectra of plants that grow in zones with presence/ absence of deep hydrogen emissions have been ascertained. The main variations have been recorded at wavenumbers of 1380, 1522, 1547, and 1600 cm, which are responsible for stretching vibrations in lignin and β-carotene and chlorophyll a and cellulose in plant leaves. Confocal fluorescence microscopy showed an increase in the chloroplasts in leaves of plants which grow at hydrogen degassing territories. An optical coefficient was introduced, on the basis of which the Samara region was monitored. [ABSTRACT FROM AUTHOR]

The regulation of succinate dehydrogenase (SDH) activity and its gene expression by the phytochrome system has been demonstrated: red light (660 nm) reduces the SDH activity and the level of expression of the sdh1-2 gene. At the same time, the content of calcium cations in the nuclear fraction increases; it seems to be one of the mechanisms of phytochrome signal transduction in plant cells. Far-red light (730 nm) had opposite effects, i.e., increased SDH activity and the level of expression of the sdh1-2 gene. The data suggest that the SDH activity can be regulated at the level of expression in the green leaves of Zea mays by the phytochrome system with the involvement of calcium ions as a signal transduction messenger. [ABSTRACT FROM AUTHOR]

The article offers information on a study on the Tere-Khol Lake in the Southeastern Sayan-Tuva Highland in Russia. It informs that Tere-Khol Basin is a small pull-apart rift having gently sloped alluvial plain at its bottom and internal deltas of local and transition rivers. It was found in the study that climate of the basin has instable humidity with contrast changes during Holocene, drying tendency in the second half of the Holocene. It was found in this study that westerlies can be considered as the most probable precipitation source in Central Eurasia in Holocene period.

1,3,5-Triazinylnitrile oxides, formed by heating (2-methoxy-4-R-1,3,5-triazin-6-yl)nitroformaldoximes, react with monosubstituted and 1,1-disubstituted ethylenes with the formation of 3-(1,3,5-triazinyl)-5-monosubstituted and 3-(1,3,5-triazinyl)-5,5-disubstituted 2-isoxazolines. The cycloaddition occurs with high regioselectivity to give exclusively 2-isoxazolines substituted at the positions 3 and 5. [ABSTRACT FROM AUTHOR]

Conditions for selective substitution for one chlorine atom in 2-(R,R′-amino)-4,6-dichloro-1,3,5-triazines with a hydroxide ion were elaborated. Spectral and calculation methods showed that the products formed are in the lactam form, i.e., have the structure of 4-chloro-6-(R,R′-amino)-1,3,5-triazin-2(1 H)-ones. [ABSTRACT FROM AUTHOR]

Heating 4-R-methoxy-1,3,5-triazin-2-ylnitroformaldoximes with nitriles leads not to the formation of 1,2,4-oxadiazoles but rather to dimerization of the intermediate 1,3,5-triazinylnitrile oxides to give furoxanes. The reaction of 4-R-6-methoxy-1,3,5-triazin-2-ylnitroformaldoximes with ammonia and amines gives 1,3,5-triazinylamidoximes, which upon acylation and subsequent intramolecular cyclization yield (5-R-1,2,4-oxadiazol-3-yl)-1,3,5-triazines. [ABSTRACT FROM AUTHOR]

The reaction of 6-R-4-methoxy-1,3,5-triazin-2-ylnitroformaldoximes with dimethyl malonate gives the zwitterionic 4-methoxycarbonyl-3-(4-R-6-methoxy-1,3,5-triazin-2-yl)-4,5-dihydroisoxazol-5-ones. X-ray structural analysis has been carried out on the zwitterionic 4-methoxycarbonyl-3-(4-methoxy-6-piperidino-1,3,5-triazin-2-yl)-4,5-dihydroisoxazol-5-one. [ABSTRACT FROM AUTHOR]

A state of pre-adaptation to highly toxic doses of sulfuryl derivatives of benzimidazole and benzotriazole was developed in Staphylococcus aureus species by treating them with non-toxic doses of these compounds. Pre-treatment of S. aureus with the starting benzazolides (benzimidazole and benzotriazole) also created the pre-adaptation to their sulfuryl derivatives. Experiments on cross-pre-adaptation where the pre-adaptation to sulfuryl derivatives of benzazolides was created by the action of non-toxic doses of benzotriazole and vice versa showed that the planar structures of the double ring of benzazolide plays a key role in activation of the repair systems of S. aureus. Mathematical analysis revealed a high nonlinear correlation between the ability of a compound to create the state of pre-adaptation in S. aureus culture on one hand and the physical and chemical properties such as the lipophilicity, molecular weight and volume, and hydration energy on the other. [ABSTRACT FROM AUTHOR]

Kinetics of processes of dispersion and agglomeration and the formation of sintered powder materials based on mechanochemically activated (MCA) charges have been studied. Effects of the time of milling on the fractional composition, energy consumption of the milling process, density of the compacts and sintered samples, ultimate strength for radial compression, and the efficiency of strengthening upon the introduction of MCA additions have been shown. A technology of production of a powder antifrictional bronze with additions of MCA charges has been developed, which includes a mechanochemical activation of wastes of compacts, their pressing, and sintering. [ABSTRACT FROM AUTHOR]

Molar volumes in solutions at infinite dilution were determined for a series of intracomplex compounds of beryllium, zinc, cobalt, copper, and nickel, derived from salicyalalanilines, salicylalalkylimines, N-[(2-hydroxyphenyl)(methyl)methylene]anilines, N-[(2-hydroxyphenyl)(phenyl)methylene]aniline, as well as ethylene glycol and glycerol. An additivity scheme was constructed for calculation of the molar volumes of these compounds in solutions. Analysis of the experimental molar volumes of the systems studied showed that chelation via intramolecular complex formation almost always makes these values lower than those calculated by the additivity scheme, implying entropy stabilization of the chelates in solutions due to release of solvent molecules from the solvation shell of the molecules. It was shown that the dipole moments and Kerr constants of those compounds for which the additive scheme for calculation of molar volumes was constructed can be much easier estimated. [ABSTRACT FROM AUTHOR]

Molar volumes of a wide series of Schiff bases and their structural analogs, such as N-benzyl-ideneaniline N-oxides and azo compounds, in infinitely dilute solutions were determined. Analysis of the obtained values in terms of the additivity scheme showed that molecular fragments and substituting groups in these compounds are strongly solvated by solvent molecules, which leads to deviation of most molecules from the planar arrangement of the aryl moieties and bridging groups. Most compounds in which H-chelate rings are formed due to intramolecular hydrogen bonding are characterized by contraction of molar volumes, indicating their entropy stabilization in solution via release of solvent molecules from the solvate shell upon chelation. Methods for the determination of dipole moments and Kerr constants in solution can be simplified to a considerable extent for those compounds for which the additivity scheme was applied to calculate the molar volumes. [ABSTRACT FROM AUTHOR]

The ability of Staphylococcus aureus to adapt to the toxic action of 1,2,4-triazole and its sulfuryl derivates has been studied. A positive correlation is found between the lipophilicity and toxicity of substances. It is established that methylated derivates are more toxic than substances without methyl radicals. St. aureus species grown on a medium containing triazolides in a nontoxic dose become resistant to highly toxic doses of these substances. The possible mechanisms of St. aureus adaptation to triazolides are discussed. [ABSTRACT FROM AUTHOR]

Studies the biological properties of N,N'-sulfuryltriazole in comparison to those of its precursor, 1,2,4-triazole. Possible use of the compound as a base for the creation of antibacterial drugs and plant growth regulators; IR absorption spectra; Chromatographic mobility determined by TLC; Testing of the synthesized triazolides using Allium cepa and Drosophila melanogaster.

The available experimental data do not provide a sufficiently complete picture of the neuronal activity connected with some action of the animal, as they have been obtained under different experimental protocols and as a result of study of different cells. The present work was aimed at studying activity of the same neuron group at different moments of animal's behavior. A monkey ( Macaca nemestrina) was taught to perform a behavioral program consisting of several functional heterogeneous actions. The impulsive activity of striatal neurons was recorded in the central region of putamen with coordinates A 16.5, L7, and H 8–10 [18]. The activity of each neuron was recorded during 13 consecutive stages of the same behavioral task. As a whole, in 59 putamen neurons, 767 fragments of neuronal activity were studied. It was shown that the same neurons could be involved at different behavioral stages when the animal performed different actions. At individual stages, the number of neurons common with other behavioral stages reached 70–80% of all reactive cells at the stage. The number of the neurons common within the rest of 12 stages was determined for every program stage. The number of such common neurons established in the experiment was in 142 out of 156 cases higher than their number that could be expected on the basis of statistical relations. The data obtained indicate that the reorganization in composition of behavior-reactive cells at every behavioral stage occurs mainly by using the same neurons but not only the neurons that are specialized for the given action. The polymodality of individual striatal neurons is unlikely to be connected with that they have several functions, but results from that the same neuron can be a constituent of neuronal mosaics of different configurations corresponding to different behavioral moments. [ABSTRACT FROM AUTHOR]

Neuron spike activity was recorded in the putamen of monkeys trained to perform bimanual operant behavior consisting of nine separate steps. Neuronal reactions were present at all steps: in 52–62% of cases during movement, and in 27–36% of cases during responses to the trigger and conditioned signals and as the monkeys decided which was the working hand. The proportion of inhibitory responses to the trigger stimulus was 9%, while inhibitory reactions accounted for 68% of reactions during hand movement in response to the conditioned signal, 33% of reactions when this same hand was used to collect food reinforcement, and 33% of reactions during simultaneous movement of both hands. Reactions significantly differentiating between right- and left-sided tasks were seen at all stages of working-hand decision-taking and in reactions to the signal indicating the correctness of the selection, but were not seen for reactions to the conditioned signal or for activity accompanying movements of one of the animal's hands. These data provide evidence indicating that each step of the complex operant behavior, individual systems of putamen neuronal reactions were created with qualitatively different integral sensitivity to instantaneous behavior. [ABSTRACT FROM AUTHOR]

A monkey ( Macaca nemestrina) was trained to perform a behavioral program consisting of the selection and execution of a defined sequence of actions according to a visual conditioned signal. Discriminant analysis was used to evaluate the parameters of the collective activity of six simultaneously recorded putamen neurons. The collective activity of the neurons showed significant differences associated with execution by the monkey of left- and right-sided tasks. These differences were seen to be quite consistent in different groups of neurons. Despite the fact that putamen neurons were involved in the performance of nine separately analyzed fragments of the program, differences, were seen in two of these: at the moment of taking the decision relating to the direction of movement, and after its completion when a signal indicating the completed result was presented, independently of whether the animal selected the side for the action correctly or incorrectly. In the case of erroneous decisions, the response mosaic differed from that obtained for correct decisions; however, differences due to previously taken decisions regarding the side of action were preserved. These differences were greater at the point of program completion than at the moment of deciding the direction of movement. [ABSTRACT FROM AUTHOR]

Putamen neuron spike activity associated with motor and nonmotor functions was studied in monkeys trained to behavioral programs consisting of a series of sequential actions. In general, each putamen neuron was activated during particular behavior fragments. The association of each individual neostriatal neuron with particular behavioral fragments was not constant. When the animal performed a different version of the same program (using different conditioned signals, right- or left-sided tasks, correct or erroneous performance). the neuron could lose its association with the animal's action and become involved in a different action to which it had previously produced no response. Thus, putamen neurons could demonstrate different functional modalities in different versions of the same actions. The use of additional versions of the given program always led to increases in the numbers of behavior fragments during which there were changes in the spike activity of the neurons of interest. This effect was significantly stronger in motor fragments of the program than in nonmotor fragments. These results show that putamen neurons do not have any defined specialization and have different functional modalities when the animal performs different versions of the same action. The nature of putamen neuron involvement in sensory-cognitive processes was more stable than in the organization of motor responses. [ABSTRACT FROM AUTHOR]

The effect of copper and zinc contamination of soil on lipid peroxidation rate and accumulation of free proline in barley leaves is studied in a pot experiment. It is shown that not only the magnitude but also the direction of the effect change depending on the concentration of these elements in soil. [ABSTRACT FROM AUTHOR]

Focuses on the synthesis and genotoxicity of 4-(1H-imidazol-1-ylmethyl) phenol (I) and 4-(1H-1,2,4-triazol-1-ylmethyl)phenol (II). Histograms of the effect of azolides on the germination of Allium cepa onion seeds; Influence of the synthesized compounds on the relative duration of various stages of mitosis; Effect of xenobiotics on the cell division process and on the relative duration of mitosis stages; Difference in the character of chromosome aberrations.