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The newest structures of the east of the Taimyr Peninsula, which are manifested in relief, have been studied using the structural and geomorphological method; this allows us to identify the latest deformations, which have been compared with the features of the gravitational field and its transformants. A good correspondence between gravitational anomalies and magnitude of conerosional rises has been shown. It has been established that the selected blocks and their boundaries are attributed of to the specific features of the transformant field. The zones of seismicity within the Eastern Taimyr and adjacent territories tend to faults that were active in the Cenozoic, as well as to an elongated zone of contrasting values of the gravitational anomalies and their NW-striking transformants. [ABSTRACT FROM AUTHOR]

Changes in the morphology and structure of the GaAs surface during the deposition of an Au film by thermal evaporation in vacuum have been studied. It has been found that the deposition of an Au film with the participation of a flow of particles and light from a heated evaporator causes the appearance of photoeffects in the near-surface GaAs layers, including light diffraction on surface acoustic waves, the growth of whiskers, and electron emission, which leads to the formation of microcracks on the GaAs surface and the growth of GaAs crystallites. It is shown that the structure and composition of the film boundaries of Au and GaAs surfaces depend on the electron concentration in gallium arsenide, which ultimately determines the properties of the electrophysical parameters of the Au–GaAs contacts. [ABSTRACT FROM AUTHOR]

A set of geological and geophysical works has been carried out to study fracturing in the Jurassic–Neogene rocks of the Heracles Plateau, which included a field study of the Georgievsky fault zone and a structural and geomorphological analysis; the geophysical complex included marine seismic and magnetometric studies combined with ground-based studies using electrical resistivity tomography, gravimetry, and magnetometry. The main objects of study were the zone of the deep Georgievsky fault and feathering tectonic disturbances. Our integrated research revealed the main geological and geophysical criteria for identifying dangerous fracturing sites: an extremely heterogeneous structure of the upper part of the geoelectric section to depths of 30–40 m according to electrical survey data; seismic data indicate that Miocene limestones have extremely low strength properties in areas with increased fracturing; according to electrical survey data, the water content (humidity) of the upper part of the section changes sharply horizontally; in the karst areas, the resistivity varies sharply from the maximum values to minimum ones at certain depths. Tensile fractures that occur in areas of the positive relief of base rocks, along which landslide bodies represented by limestones flow, are particularly dangerous. [ABSTRACT FROM AUTHOR]

The modern structure of the Zagros fold-thrust structure was formed under the influence of collision processes on the eastern flank of the collision zone of Eurasia and Arabia. The work considers the features of the latest and modern geodynamic development of the Zagros as a classical collision orogen on the basis of structural-geomorphological analysis and the spatial–temporal distribution of seismicity. It is noted that the orogen is at the stage of con-erosion development. The Zagros seismic activation is associated with a greater extent with local deformations within individual blocks and is transformed in response to intense human activities in connection with extraction of hydrocarbons within the Mesopotamian lowland and the Persian Gulf. [ABSTRACT FROM AUTHOR]

The latest structural elements, as extensively developed in the form of systems of uplifts and depressions, have been identified on the basis of the comparison of relief and geological data. These elements have been studied by interpretation of satellite images and topographic maps in the form of lineaments predetermined by disjunctive dislocations. As a result of the research, the neotectonic shear stresses fields have been reconstructed with the orientation of the submeridional compression axes of the rank I tectonic stresses, which is generally in agreement with the subhorizontal compression axes established in almost all regions of Northern Eurasia and, generally, oriented submeridionally. [ABSTRACT FROM AUTHOR]

Low-power microwave irradiation on the surface of gallium arsenide leads to the quantitative changes of the ratio of the Ga and As atoms (ions), which depends on the frequency of the electromagnetic field. It is shown that a variation in the Ga/As ratio results from the resonance relaxation processes caused by the drift of excess carriers and their lifetime, while the motion of charged particles takes place along an oscillating substrate and is determined by both drift and diffusion in the presence of the field of frequency-dependent electromechanical stresses. It is found that the effect leads to the changes of both composition and concentration and type of free carriers, which, in turn, causes changes in the rheological and electrical parameters of the surface, including variations in the direction and speed of charged particles accompanied by electronic and acoustic emission. [ABSTRACT FROM AUTHOR]

We present the results of analysis of the Strombolian-type Deception volcano after its explosive caldera-forming eruption. The volcano studied, located in the South Shetland Archipelago (Antarctica), was selected in accordance with the "Strategy for the Development of the Russian Federation Activities in Antarctica for the Period until 2020 and for the Long-term Period until 2030." On the basis of original structural–geomorphic constructions and literature data, the location of volcano is substantiated, the modern tectonic structure of volcano is revealed, and the influence of geodynamic settings in adjacent regions on the evolution of the volcano is assessed. We applied the structural–geomorphic method, which is developed by the national scientific school and successfully tested in practice. The initial materials were topographic and bathymetric maps of various scales, satellite and ground-penetrating-radar images, the digital elevation model compiled, and published geophysical and geological information. It is concluded that Deception volcano was formed at the intercept between the large Hero Fracture Zone and the regional fault framing the South Shetland Archipelago from its southeast, without the influence of the geodynamic regime of the adjacent Bransfield rift, which is considered by a number of researchers to play a leading role in the evolution of the volcano. The modern volcano structure is characterized by fault-block tectonics with the domination of NE-trending faults. [ABSTRACT FROM AUTHOR]

MOF based on cobalt terephthalate and 1,10-phenanthroline was synthesized according to a modified procedure by the interaction of cobalt nitrate, terephthalic acid, and 1,10-phenanthroline in the presence of alkali. MOF has been used to extract the organic Congo red and methylene blue dyes from their aqueous solutions. The degree of removal depends on temperature and reaches values close to 100% within 60 min at 291 and 308 K. The limiting adsorption is 40 mg/g, and the Langmuir model is in good agreement with the experimental results. The antioxidant activity of MOF was evaluated on a model solution of adrenalin hydrochloride in an alkaline medium with a maximum inhibition of the oxidation of the model compound of 87.05%. The antibacterial activity of MOF against Escherichia coli (E. coli) was assessed as satisfactory, which is explained by the release of metal cations and organic ligand, and the long period of action is due to their synergistic action. [ABSTRACT FROM AUTHOR]

The GaAs surface is under investigation depending on the methods of preepitaxial processing. It is shown that the known methods of surface treatment using acid or alkaline etchants with subsequent annealing in a vacuum chamber lead to different results in terms of the composition of the near-surface layer. It is found that the physical and chemical properties of water at the stage of neutralization of the etching solution play an important role in the finish washing of GaAs. Moreover, from the remaining drops on the surface of GaAs during the drying stage either a thin layer of GaAs oxide (when using deionized water), or a layer of recrystallized GaAs (when using reagent-free modified water) can precipitate. [ABSTRACT FROM AUTHOR]

This article presents the results of structural and geomorphological analysis of the Northeastern part of Taimyr Peninsula. The main neotectonic structures of the region are identified. It is shown that the intensity of neotectonic processes increased in the Northeast direction, which is due to the influence of the Gakkel Ridge spreading zone in the Arctic Ocean. Tectonic fragmentation of Taimyr, the height of mountains, and seismic activity are increasing in the same direction. [ABSTRACT FROM AUTHOR]

The Philippine lithospheric plate is located in the zone of intensive mutual interaction between geosystems that affect the evolution of different geospheres (envelopes); at the same time, this is also one of the world regions with the highest degree of various natural hazards. The present study of temporal variations in natural catastrophes in the late 20th and early 21st centuries is based on a hypothesis about a mutual relationship between strong earthquakes, volcanic eruptions, and tropical atmospheric eddies in the regions of complex and high instability of the geospheres. [ABSTRACT FROM AUTHOR]

Changes in the state of the surface layer of semi-insulating (111) GaAs in air under the action of white light are studied using surface acoustic waves (SAWs). It is shown that, depending on the light intensity and the SAW power, the reactions of interaction with molecules, atoms, and charged particles of the air are enhanced or weakened. The role of standing acoustic waves arising in the surface layers of gallium arsenide, namely, the concentration of interaction effects in places of maximum illumination as a result of diffraction of light by standing acoustic waves, is considered. The formation of nuclei (Ga + As) in the diffraction spots, covered with layers of compounds with oxygen and carbon, either growing or spreading, is found, and the fact that the formation of an oxide layer leads to a reorientation of the GaAs surface is established. [ABSTRACT FROM AUTHOR]

Soda lakes are relic ecosystems inhabited by unique microorganisms, which are doubly extremophilic: both haloalkaliphilic and natronophilic. Two morphologically and physiologically similar monocultures of filamentous anoxygenic phototrophic bacteria (FAPB) were isolated from the water samples and biofilms on plants of the coastal zones of the steppe soda lakes Tanatar 6 and Gorchina 1 (Kulunda, Altai krai) during the season of their desalination. In their natural environments, FAPB coexisted with anoxygenic purple sulfur bacteria of the genera Chromatium,Thiocapsa, Ectothiorhodospira, and Thiorhodospira, as well as with oxygenic phototrophs (alkaliphilic cyanobacteria, euglenophytes, and diatoms). FAPB formed filaments surrounded by thin sheaths; their cells contained antenna structures (chlorosomes). Apart from small amounts of bacteriochlorophyll (BChl) a in the reaction center, both isolates contained also antenna BChl c and BChl d. Alpha- and beta-carotenes and their derivatives were also detected. FAPB grew well in the medium containing Na2S ∙ 9H2O (500 mg/L) at total mineralization of 15−30 g/L and pH 8−9.5. Identification of both cultures based on amino acid composition of the PufLM complex revealed that they belonged to the phylum Chloroflexi and were almost 100% identical both to each other and to the halo-alkaliphilic isolate "Candidatus Viridilinea mediisalina" Kir15-3F revealed previously in the Kiran soda lake (Eastern Siberia, Russia). It may be concluded that "Cand. Viridilinea mediisalina" is a typical component of Siberian soda lakes with moderate salinity. [ABSTRACT FROM AUTHOR]

While the total installed capacity of the world's solar heat supply is 480 GW (600 million m2), it is 68 MW in Russia (85 000 m2). The study presents data on five major Soviet scientific solar engineering schools, four research and design institutes, and seven solar collector factories. It mentions the leaders of solar technology in the theoretical foundations (Dr. Sci. (Tech.) B.P. Weinberg), the designs of solar collectors (SCs) (Cand. Sci. (Tech.) B.V. Petukhov), solar thermal units (Dr. Sci. (Tech.) B.V. Tarnizhevskii, Dr. Sci. (Tech.) R.R. Avezov), design (Dr. Sci. (Tech.) M.D. Rabinovich, Cand. Sci. (Tech.) Yu.K. Rashidov). In Russia, research on solar radiation is carried out at the Moscow State University (Dr. Sci. (Tech.) A.A. Solovyev, Cand. Sci. (Econ.) K.S. Degtyarev), Joint Institute for High Temperatures, Russian Academy of Sciences (Dr. Sci. (Tech.) O.S. Popel, Cand. Sci. (Tech.) S.E. Frid), and Kuban Agrarian University (Dr. Sci. (Tech.) V.A. Butuzov). The characteristics of SCs of two major Russian manufacturers are presented: NPO Mashinostroenie (Reutov, Moscow oblast) and NovyPolus (Moscow). Despite the SCs of these manufacturers having close dimensions, they differ in materials and techniques for manufacturing absorbers. The former use copper and aluminum welded absorbers, and the latter use only copper soldered absorbers. The characteristics of air and vacuum SCs of NovyPolus are presented. The study describes the technical solutions of the solar thermal unit (STU) with SCs of the NovyPolus with an area of 240 m2 in the village of Dederkoy in Tuapse in the Krasnodar krai; the cost structure with a payback period of 4.5 years is presented. The paper also presents the technical solutions of the STU with the SCs of NPO Mashinostroenie with an area of 100 m2 in the village of Arkhipo-Osipovka of the Krasnodar krai and the STU with an area of 72 m2 in the Sanatorium settlement of Yalta in the Crimea; the cost structure with a payback period of 7 to 20 years is described. [ABSTRACT FROM AUTHOR]

Structural-geomorphological analysis of the modern relief allowed us to reveal patterns in the newest structure of Western Taimyr and to show the significance of the shear horizontal displacements of structural forms, as well as the manifestation of previously formed thrusts on the relief in some areas. The neotectonic evolution of the Arctic region has been controlled by opening of the Eurasian Basin since the Oligocene. This resulted in the activation of the northeastern faults in the region with the same orientation as the transform faults of Gakkel Ridge spreading zone, which supports the active evolution of this region at the present stage. [ABSTRACT FROM AUTHOR]

A Gram-negative, anaerobic photoautotroph, nonmotile, oval bacterium possessing gas vesicles and having no prosthecae, designated as V1, was isolated from the South China Sea coastal zone. It had chlorosomes as photosynthetic structures, and bacteriochlorophyll c as the major photosynthetic pigment. The strain was found to grow at 20–35 °C, pH 6.3–8.0 (optimum, pH 7.1) and with 0.7–5.8% (w/v) NaCl (optimum, 1–1.8%). In the presence of sulfide and bicarbonate, acetate, and fructose promoted growth. The DNA G+C content was 47 mol%. While the new isolate belonged to the Chlorobiaceae genus Prosthecochloris, it exhibited low similarity of the 16S rRNA gene sequences (96.21–96.78%) to other members of this genus. Comparison of the genome nucleotide sequences of strain V1 revealed that the new isolate was remote from the Chlorobiaceae type strains both in dDDH (16.8–18.9%) and in ANI (75.2–77.8%). We propose to assign the isolate to a new species, Prosthecochloris marina sp. nov., with the type strain V1T (= VKM-3301T = KCTC 15824T). [ABSTRACT FROM AUTHOR]

The results of the fractal analysis of a drainage network reconstructed using a digital elevation model and the structural and geomorphological analysis of the relief of the Kerch Peninsula are compared. Three sectors with different geomorphological expression and the uplifts and depressions associated with them have been identified by the results of the structural and geomorphological analysis. At the same time, the newest structural geometry does not coincide with the structural geometry that developed until the Late Pliocene period. The neotectonic structures of several orders are distinguished according to the results of the structural and geomorphological analysis. The relationship between the magnitude of the fractal dimension D of the drainage network and the movement direction was found: higher values correspond to uplifts and lower values correspond to depressions. This is due to the fact that the areas of neotectonic uplifts are characterized by the active restructuring of the drainage system and the formation of new streambeds and valleys as well as the branching of streams. The increasing complexity of the river network is seen in the higher values of the fractal dimension D, which is a quantitative measure of the complexity of objects. At the same time, the increased values of the D field correlate with rather large first-order structures. It is also found that the results of fractal analysis are subject to the scale effect, and the sensitivity depends on the accuracy and scale of the data. This should be taken into account in further research. It is shown that the fractal approach is promising for the quantitative analysis of the drainage pattern in the study of the newest tectonic structures. [ABSTRACT FROM AUTHOR]

A comprehensive analysis of the Kerch Peninsula was carried out using morphostructural and geomorphological methods, as well as determination of the fractal dimension D of the drainage system. It has been discovered that increased values of the fractal dimension field correlate well with the total uplift amplitude during the Pleistocene and Holocene and worse with the most recent structures formed during the entire uplift stage of development. It can be concluded that the fractal approach for the quantitative analysis of the drainage system pattern gives good results in identifying the most recent movements and is less effective in identifying the most recent structures. The further development of the fractal analysis method is promising based on the condition of the involvement of other drainage system parameters that are widely used in geomorphological analysis. [ABSTRACT FROM AUTHOR]

This is the comparative investigation of the composition of phototrophic microbial mats developing in sulfide-rich saline Chokrak springs with outflow at the shore of the hypersaline lake Chokrak by means of next-generation sequencing. The springs are characterized by low temperature (~ 15 °C), near-neutral pH (6.7–8.5), and high-sulfide content. In the species composition the benthic microbial communities of Chokrak springs are similar to microbial mats of marine supralittoral and lagoons. Our results showed that salinity limitation had a significant effect on the species composition of benthic microbial communities developing at the outflow of the Chokrak springs. Predominant oxygenic phototrophs belonged to the genera Phormidium, Lyngbya, Leptolyngbya, Geitlerinema, and Arthrospira. Anoxygenic phototrophic bacteria were represented by halophilic green sulfur bacteria Prosthecochloris spp., halotolerant Chlorobaculum sp., as well as marine and extremely halophilic purple bacteria Roseospira, Rhodovibrio, and Halochromatium. Monoculture of a new species of halotolerant anoxygenic filamentous phototrophic bacteria was isolated. [ABSTRACT FROM AUTHOR]

The results of the structural–geomorphic analysis of the Heraklion peninsula in southwestern Crimea are presented. The Western, Central, and Southeastern segments, which differ in the density and orientation of fracturing zones and faults, drainage system characteristics, and coastal zone structure, were recognized. It was demonstrated that the neotectonic movements in the upper structural unit are manifested most distinctly above the Late Jurassic–Early Cretaceous collisional suture that was formed during the closure of the back-arc basin with oceanic crust. [ABSTRACT FROM AUTHOR]

Phototrophic communities forming in the bottom of the Berikei highly mineralized mesothermal sulfide springs (Kayakent region, Dagestan, Russia) were investigated. The Berikei springs are an interesting example of combined effect of such factors as temperature, salinity, pH, and sulfide of occurrence and structure of phototrophic microbial communities. The water was of the sodium chloride type with salinity of 48‒97 g/L, near-neutral brine pH, and sulfide concentration of ~1 mM. The temperature at the stream bottom was as high as 60°C. Elevated temperature and high salinity limited the development of phototrophic communities. Formation of cyanobacterial mats occurred at temperatures below 54°C. Phormidium-like cyanobacteria and unicellular Synechocystis sp. predominated in the mats. The number of cyanobacterial species increased at desalination to 48‒57 g/L with emergence of the species morphologically resembling Spirulina sp., Leptolyngbya sp., and Oscillatoria sp. Among anoxygenic phototrophic bacteria, halophilic purple bacteria Ectothiorhodospira sp., Marichromatium sp., and Rhodovulum sp., green sulfur bacteria Prosthecochloris sp., and unidentified Chloroflexi were present. Oxygenic photosynthesis in the mats was not inhibited by sulfide. Production of cyanobacterial mats was up to 4.7‒53.8 µg/(cm2 h). The contribution of anoxygenic phototrophic bacteria to photosynthetic production varied from 0 to 100%. The composition of this microbial community was compared to those of the phototrophic microbial communities of the mesothermal springs of the Dead Sea coast (Israel), the Washington warm lake (United States), and the Paoha Island hot springs (Mono Lake, United States. [ABSTRACT FROM AUTHOR]

Phototrophic bacterial mats from Kiran soda lake (south-eastern Siberia) were studied using integrated approach including analysis of the ion composition of water, pigments composition, bacterial diversity and the vertical distribution of phototrophic microorganisms in the mats. Bacterial diversity was investigated using microscopic examination, 16S rRNA gene Illumina sequencing and culturing methods. The mats were formed as a result of decomposition of sedimented planktonic microorganisms, among which cyanobacteria of the genus Arthrospira predominated. Cyanobacteria were the largest part of phototrophs in the mats, but anoxygenic phototrophs were significant fraction. The prevailing species of the anoxygenic phototrophic bacteria are typical for soda lakes. The mats harbored aerobic anoxygenic phototrophic bacteria, purple sulfur and non-sulfur bacteria, as well as new filamentous phototrophic Chloroflexi. New strains of Thiocapsa sp. Kir-1, Ectothiorhodospira sp. Kir-2 and Kir-4, Thiorhodospira sp. Kir-3 and novel phototrophic Chloroflexi bacterium Kir15-3F were isolated and identified. [ABSTRACT FROM AUTHOR]

This work describes the neotectonic structures of the island of Madagascar as established on the basis of structural-geomorphologic analysis and their relationships with ancient tectonic elements. [ABSTRACT FROM AUTHOR]

The influence of HO on the photodegradataion of 5-methoxypsoralen (5-MOP) in ethanol and in waterethanol solutions upon exposure to KrCl excilamp radiation (λ = 222 nm) and XeBr excilamp radiation (λ = 283 nm) is investigated. A kinematic model of photodegradation of the investigated molecule is constructed. The addition of HO resulted in a weak increase of the decay rate of 5-MOP in ethanol exposed to KrCl excilamp radiation. In water-ethanol solutions the addition of HO altered the mechanism of decay of 5-MOP irradiated by the KrCl excilamp in comparison with irradiation by the XeBr excilamp. It has been shown that upon exposure to XeBr excilamp radiation in the presence of HO, the primary photoproduct of the transformation of 5-MOP in the reaction corresponding to the first-order kinetic model is formed both in ethanol and in the water-ethanol solutions. Maximum removal of 5-MOP takes place for the ratio of initial concentrations [5-MOP]:[HO] = 1:3 after 60 min irradiation. It is found that irradiation by the XeBr excilamp the decay rate of 5-MOP is 5 times higher in the water-ethanol solutions in comparison with ethanol. Upon exposure to KrCl excilamp radiation the mechanism of 5-MOP decay corresponds to a pseudo-firstorder kinetic model. The nature of the dependence of the decay rate of 5-MOP on the irradiation time for the ratio of initial concentrations [5-MOP]:[HO] = 1:24 indicates that during decay of the initial compound a photoproduct appears in the system which decays during the irradiation time into secondary compounds. Efficient removal of 5-MOP under this irradiation takes place for the ratio of initial concentrations [5-MOP]:[HO] = 1:10 after 60 min irradiation. [ABSTRACT FROM AUTHOR]

The neotectonic pop-up structures of Southern California were studied using the structural-geomorphological method, which included the analysis of topographic maps that were constructed on the basis of digital elevation models. The data we obtained are compared with the geological structure and the kinematic model of the block structure of the region based on the analysis of the current movements in accordance with the GPS data. The applicability of this method for neotectonic reconstructions of shear zones is considered. It is shown that the structures that are identified this way may be correlated with the kinematic model of the Southern California block structure that was developed using the GPS data. [ABSTRACT FROM AUTHOR]

The applicability of the abstract physical mechanisms in studies of concrete geological processes is considered. It is shown that 'nongeological' theoretical models are an important component of the initial axiomatics in solving the fundamental and applied problems of dynamic geology. The discussed 'simple' mechanisms adequately explain the complex deterministic-chaotic dynamics of nonlinear processes related to tectonic faulting and the unpredictability of geocatastrophes in a coarsely discrete fractal medium. [ABSTRACT FROM AUTHOR]

The theoretical fundamentals of the hypothesis are given about a stationary network of faults, which activate at different orientations of global and regional stresses and/or continent rotation in a stationary force field. It is shown that in a coarsely discrete fractal medium: (a) referencing of cracks and faults to the global, regional, and local systems is not reliable; (b) preparedness of faults to slips during the reorientation of axes for stress fields of comparable scales is interrupted by new-generation faults; and (c) the new elements of the global network do not unavoidably inherit the orientations and locations of the earlier ones. [ABSTRACT FROM AUTHOR]

The absorption spectra of the triplet excited state of coumarin sensitizers are investigated both theoretically and experimentally. The most intense triplet-triplet (TT) absorption bands are determined. The experimental spectra of the T-T absorption are compared with the theoretical T-T transitions. The phosphorescence spectra of five compounds are measured at a temperature of 77 K. The quantum phosphorescence yield is determined by the method of comparison with an etalon (8-methoxypsoralen). The phosphorescence lifetime is determined for the examined molecules at a temperature of 77 K. For 3,4-phenyl-4',5'-cyclohexylpsoralen, 4'-methyl-3,4-cycloheptylpsoralen, and 4'5'-dimethyl-3,4-cyclohexylpsoralen compounds, this time is equal to 1.1, 1.25, and 2.5 s, respectively. The main energy deactivation channel for all examined compounds is the phosphorescence. The positions of the lower excited triplet states, calculated by the quantum-chemical method of intermediate neglect of differential overlap with spectroscopic parameterization (INDO/S), are confirmed by the available experimental data. [ABSTRACT FROM AUTHOR]

Two alkaliphilic strains of nonsulfur purple bacteria (NPB), B7-4 and B8-2, were isolated from moderately saline alkaline steppe lakes in southeast Siberia with pH values above 9.0. The isolates were motile, polymorphous cells (from short rods to long spindly cells) 1-2.5 × 2.5-7 μm. Intracellular membranes of vesicular type were mostly located at the cell periphery. The microorganisms contained bacteriochlorophyll a and carotenoids of the spheroidene and spirilloxanthin series. The photosynthetic apparatus was represented by LH2 and LH1 light-harvesting complexes. In the presence of organic compounds, the strains grew aerobically in the dark or anaerobically in the light. Capacity for photo- and chemoautotrophic growth was not detected. The cbbL gene encoding RuBisCO was not revealed. Optimal growth of both strains occurred at 2% NaCl (range from 0.5 to 4%), pH 8.0-8.8 (range from 7.5 to 9.7), and 25-35°C. The DNA G+C content was 67.6-69.8 mol %. Pairwise comparison of the nucleotides of the 16S rRNA genes revealed that strains B7-4 and B8-2 belonged to the same species (99.9% homology) and were most closely related to the aerobic alkaliphilic bacteriochlorophyll a-containing anoxygenic phototrophic bacterium (APB) Roseibacula alcaliphilum De (95.2%) and to NPB strains Rhodobaca barguzinensis VKM B-2406 (94.2%) and Rbc. bogoriensis LBB1 (93.9%). The isolates were closely related to the NPB Rhodobacter veldkampii DSM 11550 (94.8%) and to aerobic bacteriochlorophyll a-containing bacteria Roseinatronobacter monicus ROS 35 and Roseicitreum antarcticul ZS2-28 (93.5 and 93.9%, respectively). New strains were described as a new NPB genus and species of the family Rhodobacteriaceae, Rhodobaculum claviforme gen. nov., sp. nov., with B7-4 (VKM B-2708, LMG 28126) as the type strain. [ABSTRACT FROM AUTHOR]

Lamprobacter, the genus of halophilic purple sulfur bacteria (PSB) with the single species Lpb. modestohalophilus was described in 1979. Rod-shaped Lamprobacter cells contained gas vesicles during the nonmotile growth phase; motile cells without gas vesicles were sometimes formed. Bacteria contained bacteriochlorophyll a and a carotenoid okenone. The names of this genus and species were included in the list of approved microbial names in 1988. Since the type strain Lpb. modestohalophilus RO1 has been lost, its 16S rRNA gene sequences have not been obtained. Based on analysis of the 16S rRNA genes, a new genus Halochromatium comprising the motile extremely halophilic Chromatium-like species was proposed in 1998. Members of this genus never contain gas vesicles. In spite of the phenotypic differences between the genera Lamprobacter and Halochromatium, phylogenetic boundaries between these taxa remained undetermined. Description of a marine bacteria formerly belonging to Lamprobacter according to its morphological and physiological properties as a new Halochromatium species, Hch. roseum, resulted in additional complication of the taxonomic situation. The present work provides evidence for the preservation of two phenotypically and phylogenetically different genera, Lamprobacter and Halochromatium, Lpb. modestohalophilus is proposed as the type species of the genus Lamprobacter. Characteristics of two Lpb. modestohalophilus strains were extensively investigated, and one of them (strain Sivash) was proposed as the neotype strain of the species. It was suggested to retain the genus Halochromatium as containing extremely halophilic species Hch. salexigens and Hch. glycolicum, while transfer of the weakly halophilic species Hch. roseum to the genus Lamprobacter is proposed, resulting in a new combination Lamprobacter roseus comb. nov. [ABSTRACT FROM AUTHOR]

Five phylogenetically similar monocultures of mesophilic filamentous anoxygenic phototrophic bacteria (FAPB) were isolated from microbial mats of low-mineral (5-28 g/L) alkaline lakes in Buryat Republic, Transbaikalia and Mongolia, as well as from biofilms of an alkaline sulfide spring (3 g/L) of the Umhei hydrothermal system (Buryat Republic). New isolates were characterized by short trichomes (15-30 μm long and ∼1 μm in diameter), straight, curved, or wavy, surrounded by a thin iron-sorbing mucous sheath. Gliding motion of the trichomes was not observed. The trichomes formed bunches consisting of several filaments. Trichomes multiply by the separation of short fragments or single cells from the parental trichome. The cells in the filaments were elongated; they contained chlorosomes, gas vesicles, poly-β-hydroxybutyrate granules, and small polyphosphate inclusions. Bacteria contained bacteriochlorophylls c and a and γ-carotene. Absorption maxima of the pigments in the cells were observed at 462, (shoulder at 515), 742, 805, and 863 nm. The organisms were strict anaerobes capable of photoautotrophic growth with sulfide as an electron donor. Elemental sulfur emerged into the medium as a result of sulfide photooxidation. The organisms were tolerant to sulfide (up to 8 mM). Best growth occurred at pH 8.0, 3-15 g/L NaCl, and 1-5 g/L sodium bicarbonate. According to phylogenetic analysis, the 16S rRNA gene sequences of the FAPB isolates formed a separate cluster most closely related to the species cluster of the family Oscillochloridaceae, suborder Chloroflexinae, order Chloroflexales, class Chloroflexi. The differences with the closest 16S rRNA gene sequences of the known FAPB were 9-10%. The formal description of a new taxon, Candidatus' Chloroploca asiatica' gen. nov., sp. nov., is provided. [ABSTRACT FROM AUTHOR]

The meaning of the term lineament, the modes of their recognition, and the lineament patterns dramatically varying in interpretations by different authors, are considered. It has been shown that obligatory identification of lineaments with faults and fracture zones is mostly implied rather than corroborated by evidence. The mapping of faults in platform regions based on lineaments requires distinct geological substantiation, otherwise lineament patterns remain devoid of sense. The regmatic system of supposedly tectonic dislocations cannot form on the surface of the rotating Earth, because the operating forces are too weak. Taking into account drift of continents and their rotation in the geological past, one hardly can speak of an ancient and inherited fault network. [ABSTRACT FROM AUTHOR]

Mass-transfer processes are investigated by the chemical analysis of gallium-arsenide surface layers after irradiation of the GaAs surface with low-intensity (13-25 mW) electromagnetic waves at a frequency of 75 GHz. The electromechanical stresses on the GaAs surface are shown to change under the action of radiation, and relaxation processes with the involvement of the mass transfer of charged particles arise. As a result of irradiation, islands based on the solution (Ga + As) or GaAs compounds are precipitated, and the surface bend of the basic GaAs compound changes. In this case, the mass transfer depends on the charged-particle drift under the action of voltage and on the surface self-diffusion rate under the action of mechanical stresses. [ABSTRACT FROM AUTHOR]

A composition is proposed for titanium-containing crystal glass with high chemical stability, heat resistance and hardness. The glassmaking process is studied under laboratory conditions. To prevent iron-titanium chromophoric groups from coloring the glass it is recommended that raw material of very high purity, specifically, enriched quartz sand and enriched vein quartz of very high quality, be used. The glass is safe to produce and use. [ABSTRACT FROM AUTHOR]

Results obtained from the first stage of retrofitting and preliminary tests of the geothermal heat supply system for the Rozovyi settlement in the Krasnodar krai are presented. [ABSTRACT FROM AUTHOR]

This work studies changes of the GaAs surface state under the effect of low-intensity electron flux and under the effect of weakly ionized plasma (evaporated Au vapors in vacuum). It is shown that the structure and composition of subsurface layers not only within the irradiated region, but also beyond it, changes even under weak exposure. It is found that the content of free Ga and As atoms not included into the gallium arsenide lattice decreases under irradiation of the GaAs surface, which is characteristic for the processes of plastic deformation relaxation. Removal of strain due to diffusion creep is determined by torsional deformation. Diffusion and viscosity coefficients under irradiation by electrons point to the bulk diffusion mechanism and to the grain boundary mechanism under Au deposition. Herewith, the state of the subsurface layer corresponds to the irradiation duration. The energy parameters of this process are estimated. [ABSTRACT FROM AUTHOR]

The genes encoding the key metabolic reactions are often used as functional markers for phylogenetic analysis and microbial ecology studies. The composition and structure of the genes encoding ribulose-1,5-bisphosphate carboxylase (RuBisCO) of various photoautotrophic bacteria, representatives of the order Chromatiales, including collection strains and the strains isolated from saline and soda lakes, were studied in detail. The green-like form I RuBisCO was detected in the majority of the studied strains. In some strains, the genes encoding both form I and form II RuBisCO were present, which has not been previously known for the representatives of this group of bacteria. Moreover, RuBisCO genes were used as functional markers to investigate the autotrophic microbial community inhabiting the upper horizons of bottom sediments of two saline soda lakes and two hypersaline neutral lakes of the Kulunda Steppe. In general, the diversity of autotrophic bacteria in the studied sediment horizons was low. In soda lakes, haloalkaliphilic cyanobacteria and sulfuroxidizing bacteria (SOB) of the genus Halorhodospira were predominant. In saline lakes, halophilic chemoautotrophic SOB Halothiobacillus and Thioalkalivibrio were found, as well as photoautotrophic bacteria of the genus Ectothiorhodosinus and cyanobacteria. Many phylotypes remained unidentified, which indicates the presence of groups of microorganisms with an unknown type of metabolism. [ABSTRACT FROM AUTHOR]

Two strains of purple sulfur bacteria of the family Ectothiorhodospiraceae were isolated from moderately saline steppe lakes (with pH above 9.0) of the Transbaikal region (strain B7-7) and Mongolia (strain M10). The cells of the novel strains were spiral-shaped, 2.0-3.2 × 9.6-20.0 μm, motile due to a polar tuft of flagella. Photosynthetic pigments were represented by bacteriochlorophyll a and carotenoids of the spirilloxanthin series. Photosynthetic membranes were represented by long strands of lamellae distributed throughout the whole cell; unlike most Ectothiorhodospiraceae species, the membranes were not packed into regular stacks. Bacteria were capable of weak growth on sulfide and slow grow on hydrogen under photoautotrophic conditions. The best growth was noted on sulfide in the presence of acetate and bicarbonate. Thiosulfate did not stimulate phototrophic growth, even in the presence of organic substrates. The new isolates were alkaliphiles growing at a pH optimum of 9-10. Growth was possible within a salinity range of 0-80 g/l NaCl, with an optimum at 5-15 g/l NaCl. The morphology, the structure of the photosynthetic apparatus (strands of lamellae), and the physiology of the new strains were similar to those of Thiorhodospira sibirica. However, analysis of the 16S rRNA gene sequences demonstrated that the studied isolates were closely related to the type strain Ectothiorhodospira shaposhnikovii (99% similarity) of the family Ectothiorhodospiraceae, whereas the level of similarity between the new strains and Thiorhodospira sibirica was only 94-95%. According to the results of DNA-DNA hybridization, the DNA-DNA homology level between the tested strains was almost 100%; the similarity between the new isolates and the type strain Ectothiorhodospira shaposhnikovii was only 58%. The isolates differed from other representatives of the genus Ectothiorhodospira in the structure of the gene encoding the key enzyme of autotrophic CO fixation, ribulose-1,5-bisphosphate carboxylase (RuBisCo), which was similar to the RuBisCo genes of members of another family of sulfur bacteria, Chromatiaceae. The new isolates of purple bacteria were described as a new species of the genus Ectothiorhodospira, Ect. magna sp. nov. with the type strain B7-7 (= VKM B-2537 = DSM 22250). [ABSTRACT FROM AUTHOR]

During the work on the project on the identification of proteinkinases that phosphorylate protein microtubules of plants, we revealed with the help of bioinformatics the genes of assumed homologues of proteinkinase MAST2 that is associated with microtubules in animal cells. Respectively, the gene of the closest homologue of MAST2, the assumed protein that we have named GMLK (Grape MAST2-Like Kinase, A7NTE9_VITVI) was identified in the genome of grape Vitis vinifera. This study presents the results of the successful cloning of protein GMLK (A7NTE9_VITVI) cDNA from the leaves of the Pinot Noir grape. [ABSTRACT FROM AUTHOR]

The physicochemical properties, species composition, and vertical distribution of microorganisms in the water column, shoreline microbial mat, and small shoreline mud volcanoes of the stratified soda Lake Doroninskoe were investigated in September 2007. The lake is located in the Transbaikal region, in the permafrost zone (51°25′N; 112°28′E). The maximal depth of the contemporary lake is about 6 m, the pH value of the water is 9.72, and the water mineralization in the near-bottom horizon is 32.3 g l−1. In summer, the surface oxygen-containing horizon of the water column becomes demineralized to 26.5 g l−1; at a depth of 3.5–4.0 m, an abrupt transition occurs to the aerobic zone containing hydrosulfide (up to 12.56 g l−1). Hydrosulfide was also detected in trace quantities in the upper water horizons. The density stratification of the water column usually ensures stable anaerobic conditions until the freezing period (November and December). The primary production of oxygenic phototrophs reached 176–230 μg l−1. High rates of dark CO2 assimilation (61–240 μg l−1) were detected in the chemocline. Within this zone, an alkaliphilic species of sulfur-oxidizing bacteria of the genus Thioalkalivibrio was detected (104 cells ml−1). Lithoheterotrophic bacteria Halomonas spp., as well as bacteriochlorophyll a-containing aerobic anoxygenic phototrophic bacteria (AAP) Roseinatronobacter sp. capable of thiosulfate oxidation, were isolated from samples collected from the aerobic zone (0–3 m). The water transparency in September was extremely low; therefore, no visible clusters of anoxygenic phototrophic bacteria (APBs) were detected at the boundary of the hydrosulfide layer. However, purple sulfur bacteria which, according to the results of the 16S rRNA gene analysis, belong to the species Thioalkalicoccus limnaeus, Ectothiorhodospira variabilis, “Ect. magna,” and Ect. shaposhnikovii, were isolated from samples of deep silt sediments. Ect. variabilis and Ect. shaposhnikovii were the major APB species in the shoreline algo-bacterial mat. The halotolerant bacterium Ect. shaposhnikovii, purple nonsulfur bacteria of the genus Rhodobacter, and AAP of Roseococcus sp. were isolated from the samples collected from mud volcanoes. All these species are alkaliphiles, moderate halophiles, or halotolerant microorganisms. [ABSTRACT FROM AUTHOR]

Scales and efficiency of using geothermal resources in Krasnodar krai for producing thermal energy are analyzed. Results from optimization of the technological circuit and designing of a geothermal system for supplying heat to the Rozovyi settlement in Krasnodar krai are presented. [ABSTRACT FROM AUTHOR]

A design of the microstrip antenna with an epitaxial structure used as a dielectric substrate is developed. The epitaxial structure contains a thin layer of n-type gallium arsenide of on a GaAs semi-insulating substrate. The layer thickness is selected with consideration for the carrier depletion region that appears at the interface between the metal layer, which forms the antenna, and the doped semiconductor layer. We demonstrated experimentally the possibility of application of this design as a FET antenna-generator in a frequency range of 10-15 GHz. [ABSTRACT FROM AUTHOR]

Fluorescence spectra at 298 and 77 K and phosphorescence spectra at 77 K have been measured for five new compounds. Fluorescence and phosphorescence quantum yields have been measured by comparison with a standard (8-methoxypsoralen). Phosphorescence lifetimes at 77 K have been found for 2-hydrazyl-3,4-cyclopentyl-14,14-dimethylpryanocoumarin (1.60 msec); 2-hydrazyl-3,4-cyclohexyl-7-methoxycoumarin (1.35); 3,4-phenyl-4′,5′-cyclohexylpsoralen (2.50); 4′-methyl-3,4-cycloheptylpsoralen (1.10); and 4′,5′-dimethyl-3,4-cyclohexylpsoralen (1.25). The basic channel of energy deactivation for 3,4-phenyl-4′,5′-cyclohexylpsoralen; 4′-methyl-3,4-cycloheptylpsoralen; and 4′,5′-dimethyl-3,4-cyclohexylpsoralen is radiative transfer. Energies of the lowest excited triplet states have been calculated using an INDO/S quantum-chemical method. [ABSTRACT FROM AUTHOR]

It is shown that surface acoustic waves (SAWs) can affect the in situ reactions and phase transformations occurring in the surface layers of high-resistivity (semi-insulator) gallium arsenide during deposition of gold. The film formed by SAWs is multilayer in the directions both parallel and perpendicular to the surface. Amplitude, velocity, and delay of the SAWs are very sensitive to the processes occurring in the interfacial Au/GaAs layers owing to the features of their propagation vectors. [ABSTRACT FROM AUTHOR]

Surface acoustic waves are used to study the transformation of the surface of a high-resistance (semi-insulating) gallium arsenide in situ in the course of the thermal deposition of gold in vacuum. It is demonstrated that the surface modifications that involve the formation of the Au-Ga liquid phase and solid solutions based on Au3Ga, Au7Ga2, etc. result in variations in the parameters (amplitude and phase) of the transmitted acoustic wave and can be identified using such variations. [ABSTRACT FROM AUTHOR]

We present a theoretical and experimental study of the fluorescent ability of new coumarin sensitizers. Using the INDO method, we have drawn the level diagram for the photophysical processes in the coumarin molecules. We have calculated the rate constants for internal conversion and intersystem crossing and the radiative rate constants. We have determined the experimental and theoretical fluorescence yields of the test compounds. [ABSTRACT FROM AUTHOR]

Psoralens (furocoumarines) are photosensitizers of vegetative origin increasing the sensitivity of biological objects to near-ultraviolet radiation (UV-A, 320–400 nm). In the present work, the influence of substitution on the energy level diagram is considered for the first element of the series-psoralen. The absorption and fluorescence spectra are investigated with the use of an SM-2203 spectrofluorimeter, and theoretical calculations are carried out. In addition, the results obtained are compared with the calculated and experimental results of other authors. The employed method of intermediate neglect of differential overlap (INDO) yields such parameters as an oscillator force, nature and energy of the transition, positions of triplets and singlets, etc. The geometry is optimized by the semi-empirical PM3 method of the program Hyperchem 6.03. A comparison of the calculated results for the examined compounds demonstrates that after the substitution, the absorption spectra are shifted toward the red range. The lower excited singlet of the 21,22-dimethyl-10,11-cyclohexylpsoralen compound lies higher than that of psoralen and 10,11-phenyl-21,22-cyclohexylpsoralen; it is located at 332 nm. The absorption spectra from the excited states undergo a bathochromic shift after the substitution. The most intensive T-T absorption bands are also indicated in this work. [ABSTRACT FROM AUTHOR]

We have studied the effect of two detoxifying factors (UV radiation from different sources and humic substances) on the toxicity of alcoholic solutions of substituted coumarins. The change in the characteristics of the substituted coumarins was monitored spectrophotometrically. The toxicity of solutions of the substituted coumarins was monitored using a bioluminescence test system. We have shown that efficient detoxification of an alcoholic solution of coumarins occurs as a result of addition of humic substances. We have observed a dependence of the detoxification both on the structure of the studied compounds and on the characteristics of the source. [ABSTRACT FROM AUTHOR]

This paper discusses application of a structural-morphologic method for interpreting covered territories; in the present case, covered by lava flows. The study resulted in recognizing a network of recent faults and in determining their strike-slip kinematics. The relation of volcanoes and thermal springs to these faults is discussed. [ABSTRACT FROM AUTHOR]