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Data on the number and diversity of psychrotolerant yeast isolated from high-altitude and surface samples of atmospheric aerosol from southwestern Siberia are derived from a microbiological study. According to certain phenotypic and genomic characteristics, the yeast isolates are referred to the Saccharomyces, Candida, Sporidiobolus, Aureobasidium, Sporobolomyces, Cryptococcus, Rhodotorula, and some other genera. Both saprophytic and pathogenic microorganisms are detected. Aureobasidium yeast strains are revealed, which actively produce exopolysaccharides and melanin and are promising for biotechnological developments.

Issues concerning the detection of biomolecular targets by biosensors based on silicon nanowire field-effect transistors are discussed. We list and discuss steps in the surface preparation of silicon nanowires that lead to the efficient, highly sensitive, and selective detection of various analytes. The procedures for cleaning and activation of the surface of the silicon nanowires are addressed. Wet and dry methods for surface cleaning as well as surface-modification strategies applicable to transducers of biosensors are described. Surface modification by silane derivatives (i.e., silanization) and linker attachment is paid particular attention. The causes underlying the undesirable screening effect affecting a nanowire surface upon analyte detection in solutions are provided. The key requirements and strategies relevant to different steps in the preparation of biosensor surfaces that lead to improvement in their performance are mentioned.

The atmospheric air quality is determined by the concentrations of some gaseous pollutants and mass concentrations of aerosol particles of different sizes. A wide range of atmospheric pollutants in both gaseous and aerosol phases was studied in the vicinity of Gelendzhik in July 2009, simultaneously at several land sites, in the water area of the bay, and at altitudes of up to 2200m. No such complex experiments were carried out in that region before. The following characteristics of the atmospheric aerosol (3 nm–32 μm in size) were studied: elemental composition of particles (23 chemical elements) and concentrations of polyaromatic hydrocarbons (14 compounds), unsaturated hydrocarbons, total protein, biotoxins, and culturable microorganisms. The concentration fields of different air pollutants and the complex air pollution index were constructed using mathematical models of pollutant propagation and data on the hydrometeorological conditions during the period of measurements. The sources of aerosols in the region were detected from the study of the chemical composition of airborne particles. The results allowed us to estimate air pollutants and to calculate the complex air pollution index for the Gelendzhik area. The daily average concentrations of all the pollutants were compared to the daily average maximum permissible concentrations. All these concentrations were less than daily average maximum permissible concentrations. The complex air pollution index did not exceed 1. Hence, the air in the vicinity of Gelendzhik did not contain any significant pollutants in the period under study.

The data on insecticidal, antimicrobial, and antiviral activity of Bacillus thuringiensis (Bt) strains isolated in the microbiological study of height and ground atmospheric aerosol samples taken in the South of Western Siberia are presented. Among 36 isolated bacteria determined as related to the Bt species, 15 strains were relegated to the Bt ssp. kurstaki subspecies by results of intraspecific testing and studied for the presence of antagonistic attributes. In spite of long wandering in extreme conditions in the composition of atmospheric aerosols, including higher atmospheric layer (up to 7 km), the isolated Bt ssp. kurstaki strains keep high (inherent to this subspecies) entomopathogenic activity, possessed the ability to inhibit the multiplication of such pathogenic microorganisms as Staphylococcus aureus, Salmonella thyphimurium, Shigella sonnei, Candida albicans, and others, and manifested the ability to effectively neutralize the multiplication of the A/chicken/Kurgan/05/2005 (A/H5N1) avian influenza virus and A/Aichi/2/68 (A/H3N2) human virus. Properties of Bt strains isolated from atmospheric aerosols not only verified their well-known resistance to unfavorable factors of the environment but also exhibited the possibility of using them for developing viricides.

The paper presents unique data of a 12-year (2001-2012) monitoring of the mass concentration of atmospheric aerosol and concentrations of organic carbon (OC), elemental carbon (EC), and total protein (TP) in it at the Klyuchi site (Novosibirsk region). It was found that aerosol mass concentrations, OC, and OC/EC ratio have an increasing trend, and TP has a decreasing trend. Seasonal changes in these concentrations and OC/EC and TP/OC ratios are also identified. The comparison of data obtained and recently published for other Asian and European regions show a good agreement between the values and trends for certain regions and the absence of agreement for other regions.

The results of many-year studies of the relationship between the physical properties and photocatalytic activity of TiO2 and Pt/TiO2 in photocatalytic purification and disinfection of air and water and water photodecomposition with oxygen evolution are presented. Recommendations are given as to finding the optimal method for platinum supporting on TiO2 to achieve the highest possible catalytic activity. Multisite kinetic models of the gas-phase oxidation of simple organic substances are considered. Methods for regenerating the photocatalyst after its deactivation in the oxidation of sulfur-containing organic substances are suggested. New data are discussed on the acceleration of air purification by the combination of photocatalytic oxidation with atmospheric electric discharges, the addition of gaseous hydrogen peroxide, and oxidation on photocatalysts existing in the aerosol state. As compared to pure TiO2, platinated titanium dioxide has a higher capability for disinfection and complete mineralization of microorganisms. Two promising methods for production of hydrogen from water using solar light are presented.

The results of the two-year observation of the atmospheric aerosol fungi concentration and diversity in the south of Western Siberia are presented. It is found that the fungi concentration in samples of atmospheric air can change dramatically: from less than 10 up to several thousands of viable fungi per cubic meter. A total of 18 genera of fungi referring to 3 subdivisions (Zygomycotina, Ascomycotina, and Deuteromycotina) were identified in the samples under study. Among them are representatives of those genera that are potentially pathogenic for human health (e.g., Aspergillus, Cladosporium, Penicillium, Alternaria, Trichoderma, etc.) and those that may be useful in modern biotechnology (e.g., Aspergillus, Aureobasidium, Ganoderma, etc.).

The search for the chemical and biomarkers of aerosol originating from the surface microlayer (SML) of water areas of health resort zones at Lake Baikal was performed. The concentrations of Ca, Mg, Na, K, Cu, Zn, Fe, Mn, Al, Ba, Pb, Cd, As, naphthalene, acenaphthene, acenaphthilene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benz(a)anthracene, perilene, benz (b) fluoranthene, benz(a) pyrene,1,2,5,6-dibenz anthracene, benz(ghi) perilene, and total protein in aerosols and water samples collected from the region were experimentally studied. A direct close interrelation was revealed between the concentrations of all chemical elements in aerosol and water samples. The highest concentrations were recorded for Ca, Mg, Na, and K. A polymerase chain reaction method was employed to determine the similar interrelation between the genetic materials of microorganisms (bacterioplankton) found in water and aerosol. A completely adequate marker reflecting the presence of aerosol generated by SML of Lake Baikal water was not found.