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Steric exclusion chromatography (SXC) is a method for separation of large target solutes based on their association with a hydrophilic stationary phase through mutual steric exclusion of polyethylene glycol (PEG). Selectivity in SXC is determined by the size or shape (or both) of the solutes alongside the size and concentration of PEG molecules. Elution is achieved by decreasing the PEG concentration. In this study, SXC applicability for the separation and purification of single-stranded (ss) and double-stranded (ds) RNA molecules was evaluated for the first time. The retention of ssRNA and dsRNA molecules of different lengths on convective interaction media (CIM) monolithic columns was systematically studied under variable PEG-6000 and NaCl concentrations. We determined that over 90% of long ssRNAs (700-6374 nucleotides) and long dsRNAs (500-6374 base pairs) are retained on the stationary phase in 15% PEG-6000 and >= 0.4 M NaCl. dsDNA and dsRNA molecules of the same length were partially separated by SXC. Separation of RNA molecules below 100 nucleotides from longer RNA species is easily achieved by SXC. Furthermore, SXC has the potential to separate dsRNAs from ssRNAs of the same length. We also demonstrated that SXC is suitable for the enrichment of ssRNA (PRR1 bacteriophage) and dsRNA (Phi6 bacteriophage) viral genomes from contaminating cellular RNA species. In summary, SXC on CIM monolithic columns is an appropriate tool for rapid RNA separation and concentration. (C) 2018 The Authors. Published by Elsevier B.V.

The article introduces tolerance training in the ESL classroom as part of a broader paradigm of teaching culture and intercultural communication skills in the process of foreign language instruction. After a brief discussion of how tolerance is currently understood in Russia and in the world, the authors present tolerance as, firstly, one of the leading values in modern education and, secondly, as the basis of productive cross-cultural interaction. They conclude with an example of an ESL workshop that embodies the paradigm of culture-based language teaching and targets tolerance as its primary educational goal.

In total 3566 blood sera samples were collected in the Russian Far East and Central and Western Siberia in 2009–2010. The presence of antibodies to influenza A/H1N1pdm, seasonal H1N1 and H3N2 influenza viruses in the sera was tested in the hemagglutination inhibition test. 29.5% of samples from the Far East were positive to pandemic influenza, this value for Central and Western Siberia is 2-fold lower (12.8% and 11%, respectively). Fifty-six influenza A/H1N1pdm viruses were isolated during 2009–2010 from samples collected in Central and Western Siberia and the Russian Far East. Molecular and genetic properties of 23 strains were studied. Nucleotide and amino-acid sequences of pandemic influenza virus strains were identical (99% identity or more) to reference strain A/California/04/2009. Sporadic substitutions in antigenic sites were detected but did not change antigenic characteristics of strains.

The dynamically equilibrium shapes of a uniform-density rotating mass of liquid (a ring) in the surface layer of a quiescent stratified ocean are determined. The examination is carried out in a plane tangential to the Earth, taking into account the vertical and horizontal projections of the angular velocity of its rotation. Exact solutions of the equations of motion of an ideal incompressibe fluid are obtained, making it possible, for a linearly stratified ocean, to determine the dynamic all equilibrium shape of the interfaces of water masses and the free boundaries of cyclonic and antocyclonic rings. These shapes comprise second-order surfaces inclined to the water level in the meridian plane, the type of surfaces depending on the governing parameters of the problem. Expressions are obtained for the angles of inclination of the principal axes. For small deviations from equilibrium, due to a difference in the gravitational forces and Archimedes forces, motion of the ring occurs, governed by the inclination of the principal axes and the nature of change (increase or reduction) in the average density of the ring, determined by the ratio of the rates of diffusion of heat and salt. The displacement along the parallel comprises geostrophic motion, for the velocity of which an analytical expression is obtained. The displacement along the meridian comprises motion over an inclined plane. An analytical expression is given that relates the change in the depth of the centre of mass of the ring to the velocity of motion along the meridian through the angle of inclination of the principal axes of the ring. This explains the motion of both types of Gulf Stream ring to the south-west and of the Oyasio ring to the north-east.

The problems of identification of slow nucleus with small atomic numbers in photographic emulsion are discussed. We proposed to measure the distance between track edge and track axis and to search the atomic numbers by minimizing the square differences between the theoretical and experimental values of these distances.

Methanotrophic bacteria utilize only methane (some species methanol) as a source of carbon and energy. They can co-metabolize a number of non-growth substrates due to the low specificity of methane monooxygenase (MMO). The reducer for monooxygenation is obtained during dehydrogenation of intermediates of methane oxidation. During growth on methane, co-metabolism of non-growth substrates leads to exhaustion of the methanotroph energy sources, accumulation of toxic products and growth cessation. To evaluate a role of the monooxygenation process in the metabolism of methanotrophs, co-metabolism of methanol and a substrate of MMO (ethane or carbon monoxide) was studied during the growth of Methylomonas rubra 15sh and Methylococcus thermophilus 111p. These organisms, being grown at low copper content, did not oxidize naphthalene. Thus, they possess particulate MMO, which can use reducing equivalents at the level of methanol dehydrogenase. Methanol did not support growth of Mc. thermophilus 111p. Growth of Mm. rubra 15sh on methanol was inefficient and was accompanied by accumulation of formaldehyde. When a second substrate (ethane or carbon monoxide) was added into the gas phase (5–20 vol.%), the growth of Mc. thermophilus 111p occurred, and the yield from methanol of Mm. rubra 15sh was enhanced. At low methanol concentration (to 12.5 mM), the yield of the Mm. rubra 15sh biomass from methanol was proportional to the amount of the second substrate co-oxidized, and the whole methanol utilized was converted into biomass. Theoretical calculations showed that such high efficiency of growth could be achieved when MMO received reducing equivalents from methanol dehydrogenase and, moreover, electron transport chain from NADH to MMO contained a proton translocating segment. Thus, monooxygenation of the MMO substrate was profitable for the methanotroph metabolism. During the growth of methanotrophs studied on methanol plus ethane or carbon monoxide, the major part of electrons of methanol utilized was used for the monooxygenation of the MMO substrate. For methanotrophs, this allows to consider the monooxygenation process as the energy yielding mechanism of the electron transport to oxygen.

The properties of In2O3-based ceramic sensors, doped with Pt4+ and Au3+ ions, at detection of NH3 and other reducing gases have been compared. It was stated that Pt increases while Au decreases In2O3 sensitivity to NH3. The ceramics resistance decreases, when In2O3 is doped with Pt. Au addition to In2O3 leads to the opposite effect. The high sensitivity of In2O3–Pt sensors to NH3 and decrease of In2O3–Pt ceramics resistance, when compared with undoped In2O3, may be caused by the formation of InxPty in In2O3–Pt systems. In2O3–Pt sensors allow analysing the content of NH3 in air in the concentration range of 15–2000 ppm.

Summary The effect of ethephon on proliferation and expansion (quantity and size) of different cell types in the leaves of winter rye seedlings was studied.At concentration between 10-3-10-1 M ethephon retarded growth of leaf blades and leaf sheaths and decreased the final cell number.This effect was accompanied by a decrease in cell number along the meristem in comparison with the high level of cell proliferation in the first (proximal) part of the meristem in growing leaves of treated plants.These data show that ethephon-produced ethylene promoted exit of meristematic cells from the mitotic cycle in the second (distal) part of the meristem.The final cell number of different cell types in treated plants decreased in various degrees.Our data showed that these differences caused an increase in the final length of some cell types or no changes in it while the length of other cell types within the same part of the treated plant leaf decreased.Such a difference in changes of cell length of ethephon-treated plants is determined by correlative connections among the cells of a growing cereal leaf.

Summary The effect of ethylene-releaser ethephon on the intensity of ethylene production, ACC content, and EFE activity in situ and in vitro (activity of ACC-oxidase) in primary leaves of intact winter rye seedlings was investigated. There were a sharp increase of ethylene production immediately after the treatment and an increase in ACC-oxidase activity in vitro and EFE activity in situ after a lag period of at least 15 min. Inversely, the level of ACC decreased after an equal lag period. Such an effect of ethephon on ethylene biosynthesis was most remarkable 1 to 24 h after the treatment. An additional treatment with 0.1 mM COS0 4 before the application of ethephon inhibited the ethylene production. It is suggested that a major part of the increase in the ethylene production is related to the decomposi- tion of ethephon having penetrated into leaf tissues, while the other part is related to an increased formation of endogenous ethylene from the accessible pool of ACC due to enhanced EFE activity. Treatment with gaseous ethylene (0.8 ppm) caused an increase in ethylene production and a decrease in ACC content. The results reveal an autocatalytic action of exogenous ethylene in intact juvenile tissues and emphasize the probable importance of EFE in a positive regulation of the ethylene formation.

Transparent fine-granular SnO2 and SnO2-Pd films (SnO2 verage particle size 25–30 nm) have been obtained by annealing of tin hydroxide sols, stabilised with oleic acid. The structure of the films was investigated by TEM, ED and Mossbauer spectroscopy. In SnO2-Pd films, annealed at 800 °C, palladium is present as homogeneously distributed thermally stable particles (d = 5–8 nm). Observed isomeric shifts of 119Sn Mossbauer spectra suggests the presence of partially reduced tin ions, Sn2+ and Sn3+, in the films. Deeper reduction of SnO2 and formation of SnO are observed in SnO2-Pd films, annealed at 500 °C. Thin-film sensors based on sol-gel obtained SnO2 and SnO2-Pd are high-sensitive to different gases (H2, CH4, NO, CO). They enable detection of CO and CH4, CO and NO selectively in mixtures by controlling of sensor's operating temperature.

A comprehensive study has been made of the relaxation of the electret homocharge σ, and of the volume γv and surface γs electrical conductivity under conditions of high humidity (95±3%), and the wetting angle п with water, using films of polymers differing in their chemical structure. The results are reported for the different specimens including the fluoropolymers F4MB-2 and FZM, polypropylene, polystyrene, polyethylene terephthalate and polyimide PM-1. The assumption that charge relaxation takes place preferentially by a surface mechanism is borne out by the experiment. Empirical equations correlating σ, γs, п and the relaxation time τr have been derived along with an expression for the function of homo-charge relaxation.

Evidence is presented on the direction of growth of incomplete electrical puncture channels (dendrites) in highly orientated polymers of different degrees of crystallinity. The weight ratio of intrafibrillar to interfibrillar interlayers has been calculated. It is shown that anisotropy of distribution of the amorphous phase leads to orientation of dendrite channels in orientated crystalline polymers. On the basis of the results obtained, the conclusion is drawn that incomplete electrical puncture channels grow predominantly in the amorphous regions of a polymer.

A laser-induced fluorescence method (LFM) is described for determination of trace amounts of uranium(VI), with a detection limit of 4 × 10 −11 g/ml. A repetitive pulsed laser, time discrimination and an averaging technique are used. The optimum time discrimination is obtained when the uranyl ion is complexed with phosphoric acid or sodium polysilicate. LFM does not need a preconcentration step or separation of uranium from interfering elements. The time needed for analysis is only 1–2 min.

Preliminary results of an experiment using nuclear emulsions exposed to a tagged photon beam at the CERN SPS (experiment WA58) are presented. Six events showing pairs of charmed particles have been found. One of these has been interpreted as an associated production of Λc+ and D 0. The mean lifetime of the neutral D meson based on three events is τ0 = (0.58−0.2+0.8 × 10−13 s,, whereas a statistical analysis of eight charged charmed particles, assumed to be D mesons, leads to an estimate of the mean lifetime of τ± ≈ 4.4 × 10−13 s.