On the Nature of the Influence of Some Mycelial Actinobacteria on the Spring Wheat Seeds Germination in Soils.

The effect of pre-sowing treatment of spring wheat seeds with suspensions of various actinomycete strains has been studied. It has been found that 4 out of 18 strains studied had a stimulating effect on seed germination in soils and plant development. The stimulation of seeds by these strains was not observed during seed germination in sand. It has been suggested that the mechanism of acceleration of seed development by actinomycetes could be based not only on the release of stimulating biologically active substances, but also on the consumption of allelotoxins by these microorganisms. The test carried out to study the possibility of actinomycete growth on a medium containing one of the most common allelotoxins, coumarin, has shown that actinomycetes promoting seed germination develop on this medium more intensively compared to strains that do not affect or inhibit the germination of spring wheat seeds. This confirms the proposed hypothesis that actinomycetes can stimulate seed germination through consumption of soil allelotoxins.

Stimulation of Seed Germination by Humic Substances: On the Nature of the Phenomenon.

The wheat seed germination and seedling growth, as well as the effect of humic substances on seed development, were compared using soils and sand as substrates. Russian Plain soils were found to considerably inhibit seed germination. Pre-sowing treatment with humic preparations resulted in a significant stimulation effect on seeds sowed into sod-podzolic soil, but not into sand. Considering a well-known phenomenon of soil allelelotoxicity, we have suggested that stimulation of seed development by humic substances is a result of seed protection by them against the allelotoxin inhibitory effect.

[Peculiarities of clinical presentations of posttraumatic stress disorder and its treatment in different types of traumatic exposures].

The authors study the exposure to different extreme events on examples of two types of stress--combat stress and the liquidation of Chernobyl accident. Thirty combatants and 33 liquidators have been examined and treated. Peculiarities of the initial study of stress reactions and posttraumatic stress disorder (PTSD) due to its main diagnostic criteria have been analyzed in each group of subjects. The authors conclude that similar pathological states, including all symptoms of PTSD, develop in response to different stressful exposures. At the same time, there are significant phenomenological differences in syndromes that are determined by the character of stressful (traumatic) event. Issues of complex treatment of patients using psychotherapy and pharmacotherapy as well as approaches to rehabilitation and social support are discussed in details.

[Thermophilic chitinolytic microorganisms of brown semidesert soil].

In brown semidesert soil, thermophilic prokaryotic organisms identified as Streptomyces roseolilacinus and Silanimonas lenta were shown to play the main role in chitin transformation at 50 degrees C. The phylogenetic positions of the isolated dominant chitinolytic microorganisms were determined on the basis of 16S rRNA gene sequencing. The consumption of chitin as a source of carbon and nitrogen by both the bacterium and the actinomycete was shown by considerable biomass accumulation, high emission of carbon dioxide, and presence in the medium of the chitinase exoenzyme.

[Methodological aspects of assessing chitin utilization by soil microorganisms].

A computational method for estimating specific activity of chitin decomposition by microorganisms is proposed. Spectrophotometric and gas chromatographic methods have been used to determine the rates of chitinase production, biomass accumulation, and carbon dioxide emission by pure cultures of microorganisms grown on a chitin-containing medium. Among dominants of the chitinolytic community of chernozem (Trichoderma viride, Stretomyces albolongus, Alcaligenes, and Arthrobacter), the highest chitinolytic activity is characteristic of prokaryotes. In brown desert-steppe soil, the main destructor prokaryotes are actinomycetes (S. roseolilacinus). The biomass of the fungus T. viride growth on the chitin-containing medium markedly exceeds that of prokaryotes, but the specific activity of respiration and chitinase production in actinomycetes S. roseolilacinus and S. albolongus is an order of magnitude higher than in T. viride.

Post-traumatic stress disorder in different types of stress (clinical features and treatment).

Two types of stress situation were compared: involvement in combat actions and working in the post-Chernobyl atomic energy station clean-up. A total of 30 subjects involved in combat actions (combatants) and 33 clean-up workers were observed for 5-6 years and 15-17 years after involvement in stress situations. Mean ages in the two groups were 27.0 +/- 2.8 and 43.7 +/- 4.5 years respectively. Clinical features were analyzed in terms of the major criteria of post-traumatic stress disorder (PTSD) - "immersion" in the experience, "avoidance," "hyperexcitability," and "social functioning." There were both common features in the two groups of subjects as well as individual characteristics dependent on the nature of the stress. Patients were treated with Coaxil at a dose of 37.5 mg/day for four weeks. In both groups of patients, Coaxil had the most favorable effects on immersion and hyperexcitability, which improved social adaptation. The "avoidance" symptom was more resistant. These studies lead to the conclusion that Coaxil is an effective agent for the treatment of different types of PTSD.

[Temperature as an autoecological factor of chitinolytic microbial complex formation in soils].

The dynamics of carbon dioxide emission from soil was studied during chitinolytic succession induced by humidification and chitin introduction at different temperatures (5, 27, and 50 degrees C) using gas chromatography. The abundance and biomass of the chitinolytic bacterial and actinomycete complex in soil were evaluated by luminescent microscopy. Active development of the chitinolytic microbial complexes was observed at all studied temperatures. The most active growth of chitinolytic microorganisms was observed at high temperature during early succession and at low temperature during late succession. High and low temperatures provided for active development of the chitinolytic microbial complex in soils confined to warm climatic zones (brown desert-steppe soil) and soils of temporary zones (gray forest soil). Actinomycetes demonstrated the most active growth among chitinolytic microorganisms in the studied soil samples both at low and high temperatures..

Focusing and directing of surface plasmon polaritons by curved chains of nanoparticles.

Excitation, focusing and directing of surface plasmon polaritons (SPPs) with curved chains of nanoparticles located on a metal surface is investigated both experimentally and theoretically. We demonstrate that, by using a relatively narrow laser beam (at normal incidence) interacting only with a portion of a curved chain of nanoparticles, one can excite an SPP beam whose divergence and propagation direction are dictated by the incident light spot size and its position along the chain. It is also found that the SPP focusing regime is strongly influenced by the chain inter-particle distance. Extensive numerical simulations of the configuration investigated experimentally are carried out for a wide set of system parameters by making use of the Green's tensor formalism and dipole approximation. Comparison of numerical results with experimental data shows good agreement with respect to the observed features in SPP focusing and directing, providing the guidelines for a proper choice of the system parameters.

[Microbial transformation of chitin in soil under anaerobic conditions].

Anaerobic chitinolytic complex was studied in three soil types: chernozem, gray forest soil, and chestnut soil. The abundance and biomass of anaerobic chitinolytic microbial complex of fungi, bacteria, and actinomycetes were evaluated by luminescent microscopy. The dynamics of methane emission from soil during chitinolytic succession was studied by gas chromatography. All three studied microbial groups proved to participate in chitin transformation in soil under anaerobic conditions. The highest biomass growth was observed among prokaryotes, particularly actinomycetes, whose biomass doubled. The increase in methane emission during chitinolytic succession was most pronounced in soils with low organic matter content.

[Posttraumatic stress disorder in different types of stressful influences].

Two types of stressful influences--the participation in combat actions and the liquidation of the Chernobyl accident consequences have been compared. Thirty combatants and 33 liquidators were followed up 5-6 and 15-17 years after the extreme situation. Clinical presentations have been analyzed using main criteria of posttraumatic stress disorder (PTSD), i.e. immersion in the experiences, avoidance, hyperactivity and social functioning. Common and peculiar presentations depending on the stress character have been found. Patients received coaxil in dosage 37.5 mg daily during 4 weeks. In both groups, the drug exerted the highest effect on symptoms of immersion and hyperactivity that improved the social adaptation. Avoidance symptoms were more resistant. It has been concluded that coaxil is an effective medication for the treatment of different PTSD types.

[Succession of chitinolytic microorganisms in chernozem soil].

The chitinolytic prokaryotic and eukaryotic microbial complex of chernozem soil has been investigated in the course of a succession initiated by the introduction of chitin and humidification. The dynamics of the cell numbers of chitinolytic microorganisms and of their biomass was assessed by fluorescent microscopy and by inoculation of selective media. Emission of carbon dioxide and nitrous oxide, as well as dinitrogen fixation, was assessed by gas chromatography. It was found that, when the succession was initiated by the introduction of both chitin and humidification, it resulted in greater cell numbers and biomass of chitinolytic microorganisms and higher levels of CO2 and N2O emission and of nitrogen fixation than when the succession was initiated by humidification alone. As compared to the control samples, a significant (twofold) increase in the prokaryote cell number and biomass was found on the fourth day of the succession initiated by humidification and introduction of chitin. One week after the initiation of succession, the fungal biomass and length of mycelium were twice as high as those in the control samples. These results led to the conclusion that chitin utilization in chernozem soil starts during the initial stages of succession and is performed by both prokaryotic and eukaryotic microorganisms.

[Coupling of microbial processes of methane and ammonium oxidation in soils]. / Sopriazhenie protsessov mikrobnogo okisleniia metana i ammoniia v pochvakh.

The effect of ammonium ions on the activity of methane oxidation in soils was studied. The degree of inhibition of the methanotrophic activity in the presence of ammonium in the soil solution was quantitatively assessed as dependent on ammonium concentration and the properties of different types of soils of the European part of Russia.

[Microbial destruction of harmful organic contaminants inherent to atmosphere of living space]. / Mikrobiologicheskaia destruktsiia vrednykh organicheskikh primesei, svoistvennykh atmosfere obitaemykh pomeshchenii.

The investigation into the microbial destruction of harmful organic contaminants in the air of habitable rooms was performed with the assumption that microorganisms have labile metabolism and synthesize inducible enzymes involved in transformation of organics compounds. Based on our observations, Methylobacterium D-08 and Arthrobacter pastens are able to synthesize inducible enzymes and transform ethanol, acetic acid, acetone, and aldehyde. Association of these microorganisms does not reveal acute antagonism in case of co-cultivation on mineral substrates with carbon provided by ethanol, acidic acid, acetone, and acetate aldehyde. The most rapid growth of microorganisms was observed at 28 degrees C and pH 7. Determination of the effects of different concentrations of harmful organics on carbon dioxide production by the microbial association showed that the threshold concentration of acetate aldehyde was close to 2 mg/l and acetone--4 mg/l. The transformation activity was not reduced even at the ethanol and acidic acid concentrations of 80 and 100 mg/l, respectively. The association of A. pastens and M.D-08 oxidized ethanol, acidic acid, acetone and acetate aldehyde to carbon dioxide and water up to 90%.

[Biological activity of ancient cultivated soil with buried horizons (the Iverskii monastery, XVII century)]. / Biologicheskaia aktivnost' drevnekul'turnogo agrozema s pogrebennymi gorizontami (Iverskii monastyr', XVII v.).

The biological activity of an ancient cultivated soil that has been in intense agricultural use since approximately the first half of the XVII century was studied. The potential biological activity of the buried horizon of the antient cultivated soil was higher than that of its modern horizon or that of the noncultivated soil of an adjacent territory occurring under similar lithological and geomorphological conditions. A decrease rate of oxidative processes (decreased rates of CO2 production and CH4 oxidation) and an increased rate of reductive processes (denitrification and nitrogen fixation) were found in the buried horizon. A high potential denitrification activity (with predominant formation of nitrous oxide) was found in the buried horizon; in the upper horizon, the end product was molecular nitrogen.

[Taxonomy of denitrifying bacteria in soddy podzolic soil]. / Taksonomicheskii sostav denitrifitsiruiushchikh bakterii v dernovo-podzolistoi pochve.

The taxonomic composition of denitrifying bacteria in soddy podzolic soil was studied by the succession analysis method. This method revealed a significant variation in the taxonomic composition of denitrifying microorganisms in the course of succession. In contrast to succession analysis, the single microbiological analysis of soil samples reflected only the late stage of succession and thus led to an underestimation of the major members of succession. Myxobacteria were found to be the most active denitrifiers at the early stages of succession, whereas bacilli dominated at its late stages. The bacilli were represented by three facultatively anaerobic species, Bacillus cereus, Bac. circulans, and Bac. polymyxa.

[Absorption of nitric oxide by a strain of Bacillus stearothermophilus and its use in a bioreactor for purifying air]. / Pogloshchenie okisi azota shtammom Bacillus stearothermophilus i ego ispol'zovanie i bioreaktore dlia ochistki vozdukha.

A new Bacillus stearothermophilus strain, INMI 50, was isolated and identified. Cells of this strain immobilized on a ceramic carrier demonstrated a high NO uptake in a bioreactor. The bioreactor volume was 4 l; air flow, 100 l/h; initial NO concentration, 5 ppm; and temperature, 60 degrees C. Glycerol or 1,2-propanediol was used as carbon and energy source. The uptake of NO was 60-90% of the initial concentration over six months of continuous operation of the bioreactor. The developed procedure can be used for removal of nitrogen oxide from products of combustion of diesel fuel or from air in production areas.

[Kinetics of Streptomyces baarnensis growth and antibiotic synthesis in batch and dialysis cultures]. / Kinetika rosta Streptomyces baarnensis i sintez antibiotika v periodicheskoi i dializnoi kul'turakh.

The kinetics of biomass and antibiotic formation in batch and dialysis culture of Streptomyces baarnensis at various initial concentrations limiting the substrate growth (glucose) has been studied. The antibiotic substances were synthesized by actively growing culture, its concentration in the cultural media was maximum in the log-phase. In continuous dialysis culture on the background of biomass lianer growth in the course of time the constant antibiotic concentration in the media proportional to the glucose input concentration has been established. The inactivation (decomposition) of antibiotic was immediately initiated after discontinuation of substrate supply and followed first kinetics order. Observed features were used for construction of kinetical model of antibiotic biosynthesis. A conclusion has been made that the dialysis culture gives opportunity for more effective antibiotic synthesis as compared with the batch one.