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We study natural vibrations of the fluid column in a vertical oil well that occur during sudden shutdown or start-up of the well (water hammer). In this case, the period of vibration and the intensity of vibration damping are determined not only by the length and diameter of the fluid column in the well and the rheological properties of the fluid, but also by the reservoir characteristics of the bottomhole zone (in particular, permeability, the quality of well perforation, and the properties of the hydraulic fractures formed). Solutions to the problem of damped natural vibrations of the fluid column in the well are found using a mathematical model describing the movement of the fluid column in the well and filtration in the bottomhole zone. Characteristic equations for determining complex frequencies (frequency of vibration and the damping coefficient) are obtained. The dependences of the vibration frequency, damping coefficient, and damping decrement on reservoir permeability are studied, and the amplitudes of vibrations at different points of the well are obtained.

—Using Raman spectroscopy, atomic force microscopy, and laser interferometry we found that variations in insulin-like growth factor (IGF-1) and purinergic compounds such as ATP in the blood influence the hemoglobin distribution and hematoporhyrin conformation in hemoglobin in erythrocytes. Our results suggest that receptor activation promotes changes in conformation of cytoskeletal protein molecules and hemoglobin.

The electrochemical activity of betulin (the ability to undergo electrochemical oxidation) in aqueous solutions is determined by voltammetry on carbon-containing (glassy-carbon) electrodes. The suggested identification method is based on measuring the values of currents corresponding to the oxidation peaks of active functional groups of betulin, their heights being linearly dependent on the betulin concentration within a range of 1 × 10–6–8 × 10–5 mol/L. The developed voltammetric procedure makes it possible to determine betulin in plant extracts. Voltammetric curves for dry betulin extracts prepared using different purification procedures are obtained to demonstrate the possibility of betulin determination. The results are confirmed in spiking tests.

A nanocomposite material based on silver nanoparticles and graphene oxide was studied in terms of its optical, electrical, and structural properties. According to the electron and atomic force microscopy data, the size of obtained nanoparticles varies mostly from 60 nm to 100 nm. The transmittance and electrical resistance of this material testify higher optical transparency and electrical conductivity than in pristine graphene oxide. The obtained nanocomposite was used to study the viral etiological factor of some types of nephropathy. Nanoobjects with the size comparable to that of viruses were discovered on the surface of the erythrocytes.

High-frequency magnetron sputtering (HFMS) at various plasma powers has been applied to obtaining hydroxyapatite (HA) coating with amorphous and crystalline structure on VT1-0 titanium. The results concerning the influence of thermal treatment on the coating under isothermal holding for 1 h at 700–1000°C are presented. Structure, phase composition, topography and morphology of the formed hydroxyapatite coatings have been analyzed by X-ray phase analysis, scanning electron microscopy, energy-dispersive spectroscopy, atomic-force microscopy, and IR spectrometry. It is found that, depending on discharge power and temperature of isothermal annealing, molecular bonds are formed that are typical for HA accompanied by variations in phase and elemental compositions.

Under laboratory conditions, the microbial communities of bottom sediments of a mud volcano Peschanka (Lake Baikal) were found to carry out anaerobic methane oxidation (AOM). After 16 days of anaerobic cultivation of the enrichment cultures, methane content in the gas phase decreased, and microbial consortia were established. The content of carbon, nitrogen, and oxygen determined by energy dispersive X-ray spectroscopy (EDS) was higher than in the nearby sediment particles. The presence of bacteria of the NC10 phylum and archaea of the ANME-2d cluster was established by fluorescent in situ hybridization (FISH).

Massive parallel sequencing of the 16S rRNA gene fragments was used to investigate the composition and diversity of microbial communities in sediments from Southern Baikal to a depth of 9 cm with 1-cm step. In the layers from the sediment surface to the lower border of oxygen penetration (2 cm), organotrophic bacteria with high similarity to the heterotrophic species Luteolibacter luojiensis constituted the largest fraction of the community. In the formation zone of Fe/Mn crusts (3–5 cm), Proteobacteria and Actinobacteria predominated in the community, while the share of Cyanobacteria was considerable. The lower reduced layers showed an increased contribution of the Bacteroidetes, while the shares of the taxa predominant in the higher layers remained significant. Analysis of archaeal 16S rRNA gene amplicons revealed predominance of the soil and aquatic Thaumarchaeota (Marine Group I lineage), which are involved in anaerobic ammonium oxidation, practically in all sediment layers. The buried oxidized layer (6–7 cm), where members of the uncultured Marine Benthic Group D lineage of the order Thermoplasmatales (Euryarchaeota) predominated, was an exception in this regard. Small numbers of archaea of the Baikal-1 lineages (below 1%) were observed in the communities from the 6–7 and 7–8 cm layers, while the archaea involved in anaerobic methane oxidation (including the ANME-2d group) were not detected.

Effect of nitric oxide (NO) on phosphorylation of soluble proteins in the cell culture of wild-type Arabidopsis thaliana (L.) Heynh. (ecoptype Columbia, Col-0) was studied. Among the identified proteins whose phosphorylation was affected by the NO donor treatment, the enzymes of primary metabolism (glyceraldehyde-3-phosphate dehydrogenase, enolase) and regulatory proteins (14-3-3-like protein GF14ω, protein-disulfide isomerase-like protein, chaperonin-60α) were detected. The results clarify possible mechanisms of NO action on primary metabolism, cell cycle, and stress-induced responses of cultured plant cells.

The chum salmon of the Amur River (the mainland part of the Far East) and the Poronai River (Terpeniya Bay, Sakhalin Island) are historically related to one another, as the drainage basins of these rivers are the remnants of a formerly single river system, the Paleoamur, which existed when Sakhalin Island was a part of the continent. Both river populations of chum salmon consist of the early-run and late-run ecological forms (seasonal races), which are also referred to as the summer and autumn races. They are reproductively isolated from each other due to their spawning at different times and in different types of spawning grounds. To assess the direction, pattern, and degree of divergence between these chum salmon races in the both river fragments since the Paleoamur, it is necessary to compare them using two types of traits: selectively neutral DNA markers and morphological and physiological traits, variations in which may have an adaptive value. For this, we have studied chum salmon from both rivers in terms of microsatellite DNA markers, body counts and measurements, body weight, and fecundity. Both in the Amur River and in the Poronai River, the autumn race of chum salmon prevails over the summer race in body length and weight, fecundity, number of pyloric caeca, and several other meristic traits. The intra-basin differences between the races are much more pronounced in the Amur chum salmon. The inter-race differences in microsatellites are also greater in the Amur chum salmon compared to the Poronai chum salmon. Using microsatellites, three levels of differentiation have been revealed: (1) between the basins of the Amur and Poronai rivers, (2) between the races within each of the river basins, (3) and between population samples within each race of each basin. A hypothesis is proposed that the currently existing races of chum salmon in the Amur and Poronai rivers have evolved since the breakup of the Paleoamur, and the intra-basin divergence of the races started in the Amur River earlier than in the Poronai River. An analysis of our own data and the published data suggests that the adaptation of the seasonal races of chum salmon to the conditions of their spawning grounds is determined by a complex of morphological and physiological traits, including the number of pyloric caeca, which is an adaptive and highly heritable trait associated with the incubation temperature of the water.

Massive parallel sequencing (the Roche 454 platform) of the 16S rRNA gene fragments was used to investigate microbial diversity in the sediments of the Posolsk Bank cold methane seep. Bacterial communities from all sediment horizons were found to contain members of the phyla Actinobacteria, Bacteroidetes, Deinococcus-Thermus, Firmicutes, Nitrospirae, Chloroflexi, Proteobacteria, and the candidate phyla Aminicenantes (OP8) and Atribacteria (OP9). Among Bacteria, members of the Chloroflexi and Proteobacteria were the most numerous (42 and 46%, respectively). Among archaea, the Thaumarchaeota predominated in the upper sediment layer (40.1%), while Bathyarchaeota (54.2%) and Euryarchaeota (95%) were predominant at 70 and 140 cm, respectively. Specific migration pathways of fluid flows circulating in the zone of gas hydrate stability (400 m) may be responsible for considerable numbers of the sequences of Chloroflexi, Acidobacteria, and the candidate phyla Aminicenantes and Atribacteria in the upper sediment layers and of the Deinococcus-Thermus phylum in deep bottom sediments.

Four types of three-dimensional plasma capillary-porous titanium coatings for model intraosseous implants are developed. By means of pulsed microplasma oxidation in solutions or plasma spraying of powders, additional bioactive coatings on the basis of calcium phosphates are deposited on the Ti coating surface. Shear strength values of the interface between the implants coated and osseous block after 16 weeks of implantation are 4.25–4.81 MPa, while for implants with additional plasma hydroxyapatite coating it exceeds 6.19 MPa after 4 weeks of implantation.

Microbial diversity in the sediments of the Kara Sea shelf and the southern Yenisei Bay, differing in pore water mineralization, was studied using massive parallel pyrosequencing according to the 454 (Roche) technology. Members of the same phyla (Cyanobacteria, Verrucomicrobia, Actinobacteria, Proteobacteria, and Bacteroidetes) predominated in bacterial communities of the sediments, while their ratio and taxonomic composition varied within the phyla and depended on pore water mineralization. Increasing salinity gradient was found to coincide with increased share of the γ-Proteobacteria and decreased abundance of α- and β-Proteo- bacteria, as well as of the phyla Verrucomicrobia, Chloroflexi, Chlorobi, and Acidobacteria. Archaeal diversity was lower, with Thaumarchaeota predominant in the sediments with high and low mineralization, while Crenarchaeota predominated in moderately mineralized sediments. Microbial communities of the Kara Sea shelf and Yenisei Gulf sediments were found to contain the organisms capable of utilization of a broad spectrum of carbon sources, including gaseous and petroleum hydrocarbons.

Ethylene, being one of five classical plant phytohormones is involved in regulation of numerous physiological processes. There are contradictory data about the effect of ethylene on the cell growth and division; although it is accepted that in culture flasks, the content of ethylene rises to a few tens of μL/L and production of ethylene is associated with the periods of active growth of the cells in vitro. We revealed a strong correlation (r = 0.96) between ethylene production and specific rate of dry weight accumulation in suspension cell cultures of Ajuga turkestanica, heterotrophic and mixotrophic strains of Arabidopsis thaliana, Beta vulgaris, Euonymus maximoviczianus, Medicago sativa, Panax ginseng, and Triticum timopheevii. In heterotrophic cell culture of A. thaliana, the peaks and general shape of the curves describing dynamics of ethylene production, the number of S-phase cells, and specific rate of increase in cell number coincided in log phase and in the phase of growth deceleration. Pretreatment of subculture inoculum with 100 μL/L ethylene caused doubling of S-phase cell number after 3-h-long culturing in fresh nutrient medium. It was found that exogenous ethylene affects the number of S-phase cells only when the level of endogenously produced ethylene is low.

Research performed over the last few years identified nitric oxide (NO) as an intracellular signaling molecule involved in regulation of plant physiological processes at all stages of the life cycle. Nevertheless, some extremely important aspects of NO biology are still far from being clarified. There exist different points of view on NO formation and utilization in plants. The mechanisms of perception and transduction of the NO signal are not yet fully understood, and the origin of specificity underlying coordinated activation of responses to NO remains unresolved. It is reasonable to expect that the deep knowledge of NO functioning in animals may provide some keys to these questions. Such a comparative analysis is a way to reveal similarities and emphasize the differences in the current understanding of the NO role in plants. The present lecture highlights these aspects of NO functioning.

Beginning with the pioneering work of Salic and Mitchison (2008), the application of thymidine analogue 5�ethynyl�2'�deoxyuridine (E dU) for the detection of cells replicating DNA is actively expanding. Being incorporated into DNA, this nucleoside after click reaction of azide-alkyne cycloaddition with azides of fluorochromes can be easily detected by fluorescence. Recently, protocols of EdU application in combi� nation with click reaction adapted for plant cells appeared, and they are help for a monitoring Speriod of the cell cycle in the root meristems and in vitro cultured cells with the help of a microscope and flow cytometer. In this work, we focused some details of developed methods and their modifications and also recommended new protocols. In particular, we suggested combining EdU incorporation into the cells replicating DNA with subsequent isolation of protoplasts from them and their preparation for the microscopic analysis and flow cytometry. In addition, the method of determination of EdU phosphorylation dynamics in the cells in vivo is suggested.Arabidopsis thaliana, Chlamydomonas reinhardtii, Synechocystis, Vigna radiata, cell cycle, cell cul� ture, nucleotides, Speriod, protoplasts, flow cyto metry, thymidine kinase, fluorescence microscopy

Contradictory data about ethylene influence on cell growth and division prompted us to investigate cytophysiological characteristics of suspension cultures of Arabidopsis thaliana of wild type Col-0 and ert1-1 mutant carrying a point mutation in the site of ethylene binding by the ETR1 receptor. Some cytophysiological characteristics of the etr1-1 cultivated cells differed from those of Col-0: the growth rate of mutant cells was less and cell sizes were smaller, the culture was committed to the formation of tracheary elements (TE), had a pronounced modal class of nuclei (54%) with the amount of DNA 8C and a tendency to expand the ploidy toward 32C. Despite the absence of ethylene perception by the ETR1 receptor, the cell culture of mutant responded to treatment with ethylene by growth acceleration, an increase in cell viability and in the number of cells in the S-phase of the cell cycle. The inhibitor of ethylene binding to receptors, 1-methylcyclopropene, suppressed growth and viability of the cells of both genotypes. In the etr1-1 cell culture, the inhibitor reduced the number of S-phase nuclei and activated TE formation. All data obtained indicate that ethylene perception and transduction of ethylene signal are required for the maintenance of cell viability and active in vitro growth. It is supposed that the functional activity of the ETR1 receptor is necessary for optimal cell expansion, whereas other receptors are responsible for cell proliferation.

Using methods of molecular biology (PCR and cloning), we studied the diversity of microorganisms in the surface layers of bottom sediments from the bays of Gydan and Yenisei of the Kara Sea, which have different component composition of the pore water and mineralization level. Representatives of the domains Bacteria and Archaea were identified based on the analysis of the 16S rRNA gene fragment nucleotide sequences. The composition of the community of microorganisms in the bottom sediments changed with the changing salinity gradient of the pore waters. The phylogenetic analysis of the nucleotide sequences showed that the composition of the microbial communities in the southern parts of these bays was affected by fresh-water flows from rivers and streams from the lakes within the catchment area, whereas that in the northern parts was influenced by sea waters. The results indicate the presence of bacteria in the bottom sediments that are capable of using a wide range of substrates as a carbon source including hydrocarbons and organochlorine and aromatic compounds. These data can also indicate the presence of different pollutants in the sediments of these areas and the potential ability of bacteria to degrade chemical compounds that enter the waters and bottom sediments of the Kara Sea.

We have studied the influence of NADP+ on routine electrocardiography (ECG) in 6-month-old C57BL/6 and mdx mice. The animals were anesthetized by ether before ECG recording. ECG registration was carried out at a speed of 100 mm/s. The first ECG recording was made before intraperitoneal NADP+ injection in a dose of 13 or 80 mg/kg. The second ECG recording was made 10 min after NADP+ injection. Anesthesia was then terminated. The mice were occasionally anesthetized 45–60 min later, and the third ECG was recorded 1 h after injection of NADP+. ECG recording was carried out at a speed of 100 mm/s in standard leads I, II, and III and unipolar leads AvR, AvL, and AvF. Values of standard ECG characteristics, such as the P wave and the intervals PQ, QT, RR, and the QRS complex, were measured in milliseconds in standard lead II. We did not observe any differences between ECG magnitudes of 2- to 3-month-old C57BL/6 and mdx mice during trial experiments. Mice of both strains had a sinus rhythm in their heart rate. The QRS complex in mdx mice had a tendency to be larger than in C57BL/6 mice. Heart rates fluctuated between 722 ± 22 and 681 ± 21 beats per minute. The effect of NADP+ was studied in 6-month-old male mice. The increase in the RR interval and the decline in heart rate from 697 ± 21 to 461 ± 23 and 491 ± 28 beats per min for C57BL/6 mice (p < 0.01) and from 722 ± 28 beats per minute to 454 ± 31 beats per min for mdx mice were registered 10 min after NADP+ injection at a dose of 80 mg/kg. The increase in the RR interval can be explained by an increase in the QT interval. A statistically significant reduction in the QT interval leading to a diminished RR interval was observed in mdx mice 1 h after NADP+ injection. NADP+ at a dose of 13 mg/kg did not significantly change the ECG properties in mdx mice. ECG of mdx mice was characterized by negative repolarization of the T wave in 37% of all leads. The amount of leads with negative T-wave repolarization decreased up to 3% 1 h after NADP+ injection in dose of 80 mg/kg. The results have shown that cytomembranes of ventricular cardiac myocytes and the degree of oxidative stress are the main targets of the action of NADP+ in C57BL/6 and mdx mouse hearts.

Porphyrins are a chemical class that is widely used in drug design. Cationic porphyrins may bind to DNA guanine quadruplexes. We report the parameters of the binding of 5,10,15,20-tetrakis(N-carboxymethyl-4-pyridinium) porphyrin (P1) and 5,10,15,20-tetrakis(N-etoxycarbonylmethyl-4-pyridinium) porphyrin (P2) to antiparallel telomeric G-quadruplex formed by d(TTAGGG)4 sequence (TelQ). The binding constants (K i ) and the number of binding sites (N j ) were determined from absorption isotherms generated from the absorption spectra of complexes of P1 and P2 with TelQ. Compound P1 demonstrated a high affinity to TelQ (K i = (40 ± 6) × 106 M−1, N 1 = 1; K 2 = (5.4 ± 0.4) × 106 M−1, N 2 = 2). In contrast, the binding constants of P2-TelQ complexes (K 1 = (3.1 ± 0.2) × 106 M−1, N 1 = 1; K 2 = (1.2 ± 0.2) × 106 M−1, N 2 = 2) were one order of magnitude smaller than the corresponding values for P2-TelQ complexes. Measurements of the quantum yield and fluorescence lifetime of the drug’s TelQ complexes revealed two types of binding sites for P1 and P2 on the quadruplex oligonucleotide. We concluded that strong complexes can result from the interaction of the porphyrins with TTA loops whereas the weaker complexes are formed with G-quartets. The altered TelQ conformation detected by the circular dichroism spectra of P1-TelQ complexes can be explained by the disruption of the G-quartet. We conclude that peripheral carboxy groups contribute to the high affinity of P1 for the antiparallel telomeric G-quadruplex.

In this work, the results of microbiological and molecular genetic investigation of the microorganisms inhabiting the Kara Sea and the adjacent Yenisei and Gydanskii Bays are presented. The microorganisms isolated from the samples collected in the studied area belonged to 4 phyla and 11 genera. Bacteria of two phyla, Firmicutes and Actinobacteria, prevailed; representatives of the Gammaproteobacteria and Bacteroidetes were isolated as well. According to their phenotypic properties, the obtained pure cultures were classified with the genera Streptomyces, Rhodococcus, Micrococcus, Bacillus, Pseudomonas, Acinetobacter, Flavobacterium, and Marinococcus. Analysis of the obtained nucleotide sequences of the 16S rRNA genes confirmed that the isolates belonged to the genus Bacillus. One strain was reidentified as Brevibacillus laterosporus, and two strains were identified Aeromonas piscicola and Plantibacter sp. The results of the study of the enzymatic activity of the obtained pure psychrotolerant cultures suggest that the microbial community is actively involved in the destruction processes occurring in the studied area.

It is shown for the first time for the Enterobacteriaceae family that a gene encoding L-methionine gamma-lyase (MGL) is present in the genome of Citrobacter freundii. Homogeneous enzyme has been purified from C. freundii cells and its N-terminal sequence has been determined. The hybrid plasmid pUCmgl obtained from the C. freundii genomic library contains an EcoRI insert of about 3000 bp, which ensures the appearance of MGL activity when expressed in Escherichia coli TG1 cells. The nucleotide sequence of the EcoRI fragment contains two open reading frames. The first frame (the megL gene) encodes a protein of 398 amino acid residues that has sequence homology with MGLs from different sources. The second frame encodes a protein with sequence homology with proteins belonging to the family of permeases. To overexpress the megL gene it was cloned into pET-15b vector. Recombinant enzyme has been purified and its kinetic parameters have been determined. It is demonstrated that a presence of a hybrid plasmid pUCmgl, containing the megL gene in the E. coli K12 cells, leads to a decrease in efficiency of EcoKI-restriction. It seems likely that decomposition of L-methionine under the action of MGL leads to a decrease in the intracellular content of S-adenosylmethionine. Expression of the megL gene in the C. freundii genome occurs only upon induction by a significant amount of L-methionine.

Second-order interference with respect to the field strength during spontaneous parametric light scattering was studied under the conditions of absorption at the frequencies of idler (polariton) modes. An expression is derived that describes the scattered light intensity as a function of the scattering angle for an arbitrary shape of the nonlinear interaction region. The interference was experimentally studied for the light scattering on polaritons in a nonlinear crystal (lithium iodate, iodic acid), with a double slit placed into a pumping beam in front of the crystal.