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The concentration and diversity of cultivated bacteria and fungi isolated from samples of atmospheric aerosols taken during airborne sounding of the atmosphere at altitudes from 200 to 10,000 m above the seas of the Russian sector of the Arctic: the Barents Sea, the Kara Sea, the Laptev Sea, the East Siberian Sea, the Chukchi Sea, and the Bering Sea. Most of the samples analyzed showed the presence of pathogenic and opportunistic bacteria and fungi that can cause infectious and allergic diseases.

The purpose of this study was to compare the concentration of total protein, as well as the composition and abundance of culturable microorganisms in atmospheric aerosols collected over the Vasyugan marshes and the Karakan pine forest during a flight in September 2018 at altitudes from 500 to 7000 m. The determined concentrations of total protein in Karakan samples were on average much less than those for the same area in September of other years. The concentration and composition of microorganisms in aerosol samples were determined by cultural methods and isolate genotyping. Altitude dependences of concentrations of total protein and culturable microorganisms were revealed. A rather stable altitude profile of culturable microorganism concentration was found over the Vasyugan marshes. No microorganisms were found at altitudes 4000 and 5500 m over the Karakan pine forest. Non-spore-bearing and spore-forming bacteria, as well as molds and yeast-like fungi, were isolated from aerosol samples. A high concentration of cosmopolitan psychrotolerant yeast Aureobasidium, capable of causing severe mycoses, and opportunistic bacteria Acinetobacter were found. A great similarity of composition and an atypically high abundance of non-spore-bearing bacteria and psychrotolerant yeast-like fungi were revealed in samples taken at altitudes of 1000 and 500 m in both studied regions, which may be a consequence of large-scale horizontal transport of layers of atmospheric air contaminated with microorganisms.

In September 2020, the atmosphere was probed using the Optik Tu-134 aircraft laboratory over the waters of the Arctic Ocean seas: the Barents, Kara, Laptev, East Siberian, Chukchi, and Bering seas. Unique samples of atmospheric aerosols were collected at the altitudes from 200 to 10,000 m including samples in impingers for identification and genetic analysis of culturable microorganisms. The paper presents data on the concentrations and diversity of bacteria and fungi isolated by seeding 24 samples of atmospheric aerosols collected at different altitudes over the Arctic seas of Russia. The main morphophysiological, biochemical and genomic characteristics were obtained for 152 bacterial cultures, and the taxonomic groups they belong to were determined.

This article contains the results of research on the topical problem of highly sensitive express registration of biological objects using field-effect transistors with the surface open for analyte access, which are made based on silicon-on-insulator (SOI) films. The possibilities of dielectrophoretic effects for controlling the concentration of the analyte in the area of sensory elements are considered on the example of the indication of viruses of nuclear polyhedrosis and vaccinia. It is shown that the use of the dielectrophoresis (DEPh) effect makes it possible to solve (1) the key tasks for creating sensor systems: increasing the detecting ability, as well as exrtacting and verifying the signal from the target particles; and (2) the fundamental task: determining the charge state of the analyte in solutions without modifying the sensors’ surface. The problems and prospects of the mass application of nanowire (NW) biosensors, including those with the dielectrophoretic effect, in biotechnology, virology, etc., are discussed.

The results of identifying the vaccinia virus with the use of nanowire biosensors manufactured on the basis of silicon-on-insulator (SOI) films were presented. In our experiments, the vaccinia virus, the LIVP strain from the collection of the State Research Center of Virology and Biotechnology VECTOR of the Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing, and the rabbit blood serum containing specific polyclonal antibodies to the vaccinia virus were used. As shown by our studies, the polyvalent blood serum was electrically neutral at the sensor surface–viral suspension phase interface, the vaccinia virus was positively charged, and polyvalent blood serum–vaccinia virus vaccine complexes had a negative effective charge.

The morphological and physiological characteristics of Bacillus thuringiensis strains were analyzed and conditions for obtaining culture fluid with maximum yield of secreted RNases were determined. Zymographic analysis showed that culture fluid of B. thuringiensis strains along with low-molecular-weight (15-20 kDa) RNases contained enzymes with a molecular weight ~55 kDa and their content depended on the duration and conditions of culturing. Preparations based on B. thuringiensis culture fluid were effective against human influenza virus A/Aichi/2/68 (H3N2). In experiments on mice infected with 10 LD50 influenza virus strain A/Aichi/2/68 (H3N2), we selected effective variants of preparations based on culture fluid of B. thuringiensi strains for preventive administration that provided reliable protection of infected animals (protection coefficient 50%), close to that of the reference drug Tamiflu.

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 results of studies of a newly isolated Serratia species K-57 strain are presented. The strain is characterized by antiviral activity towards human influenza A/Aichi/2/68/H3N2, vaccinia, mouse smallpox, and herpes simplex-2 viruses. The detected characteristics of the strain, including the data on activities on nucleolytic enzymes, recommend it for the development of therapeutic and preventive antiviral drugs.

Background: Biological components of atmospheric aerosol affect the quality of atmospheric air. Long-term trends in changes of the concentrations of total protein (a universal marker of the biogenic component of atmospheric aerosol) and culturable microorganisms in the air are studied. Methods: Atmospheric air samples are taken at two locations in the south of Western Siberia and during airborne sounding of the atmosphere. Sample analysis is carried out in the laboratory using standard culture methods (culturable microorganisms) and the fluorescence method (total protein). Results: Negative trends in the average annual concentration of total protein and culturable microorganisms in the air are revealed over more than 20 years of observations. For the concentration of total protein and culturable microorganisms in the air, intra-annual dynamics is revealed. The ratio of the maximum and minimum values of these concentrations reaches an order of magnitude. The variability of concentrations does not exceed, as a rule, two times for total protein and three times for culturable microorganisms. At the same time, for the data obtained in the course of airborne sounding of the atmosphere, a high temporal stability of the vertical profiles of the studied concentrations was found. The detected biodiversity of culturable microorganisms in atmospheric air samples demonstrates a very high variability at all observation sites. Conclusions: The revealed long-term changes in the biological components of atmospheric aerosol result in a decrease in their contribution to the atmospheric air quality index.

International audience; The change of the global climate is most pronounced in the Arctic, where the air temperature increases 2 to 3 times faster than the global average. This process is associated with an increase in the concentration of greenhouse gases in the atmosphere. There are publications predicting the sharp increase in methane emissions into the atmosphere due to permafrost thawing. Therefore, it is important to study how the air composition in the Arctic changes in the changing climate. In the Russian sector of the Arctic, the air composition was measured only in the surface atmospheric layer at the coastal stations or earlier at the drifting stations. Vertical distributions of gas constituents of the atmosphere and aerosol were determined only in a few small regions. That is why the integrated experiment was carried out to measure the composition of the troposphere in the entire Russian sector of the Arctic from on board the Optik Tu-134 aircraft laboratory in the period of 4 to 17 September of 2020. The aircraft laboratory was equipped with contact and remote measurement facilities. The contact facilities were capable of measuring the concentrations of CO2, CH4, O3, CO, NOx, and SO2, as well as the disperse composition of particles in the size range from 3 nm to 32 µm, black carbon, and organic and inorganic components of atmospheric aerosol. The remote facilities were operated to measure the water transparency in the upper layer of the ocean, the chlorophyll content in water, and spectral characteristics of the underlying surface. The measured data have shown that the ocean continues absorbing CO2. This process is most intense over the Barents and Kara seas. The recorded methane concentration was increased over all the Arctic seas, reaching 2090 ppb in the near-water layer over the Kara Sea. The contents of other gas components and black carbon were close to the background level. In bioaerosol, bacteria predominated among the identified microorganisms. In most samples, they were represented by coccal forms, less often spore-forming and non-spore-bearing rod-shaped bacteria. No dependence of the representation of various bacterial genera on the height and the sampling site was revealed. The most turbid during the experiment was the upper layer of the Chukchi and Bering seas. The Barents Sea turned out to be the most transparent. The differences in extinction varied by more than a factor of 1.5. In all measurements, except for the Barents Sea, the tendency of an increase in chlorophyll fluorescence in more transparent waters was observed.

The dielectric properties of the erythrocyte were studied. Experimental methods and results of measuring the dielectric properties of individual human erythrocyte are presented. The method is theoretically justified. It is established that values of the complex permittivity of the erythrocyte, capacitance, tangent of dielectric losses remains almost constant despite significant changes in conductivity, the content of NaCl of the cell suspension. These values reflect the stability of the studied parameters of erythrocytes under conditions of changes within a wide range of the environment in which the cells are located. Complex cell permittivity and cell dielectric loss tangent are promising parameters for objective diagnostics of human diseases. The introduction of measurements of cell permittivity and cell dielectric loss tangent into medical practice will probably allow us to characterize the process of individual cell self-regulation in more detail.

Nanowire SOI biosensors are used to detect the Ebola virus VP40 protein by identifying its immune complexes with specific monoclonal antibodies (MCAs). It is shown that the reaction of specific interaction between VP40 and MCAs causes a more pronounced biosensor response than direct adsorption of VP40 or antibodies to their surface. The formation of antigen — antibody complexes leads to the accumulation of a negative charge on the biosensor surface. The protein and protein — antibody complexes are detected in real time (∼200–300 s per test sample).

To contribute to the comprehensive study of atmospheric pollution in Siberia, aircraft soundingwas carried out in Northwestern Siberian along the following route: Novosibirsk - Surgut - Igarka - Novosibirsk. This work was aimed at studying the quantity and representation of culturable microorganisms and other biogenic components of the atmosphere at altitudes up to 8,000 m. The air samples were collected to impingers (flow rate 50 ± 5 L/min) where 50 ml of Hanks’ solution (ICN Biomedicals) was used as the sorbing liquid and applied on the fibrous filters. The concentration of biogenic material was recorded, and the concentration and diversity of culturable microorganisms were determined in total protein samples. It was found that the samples of atmospheric air contained 158 mesophilic and psychrophilic microorganisms represented by such genera as Micrococcus, Staphylococcus, Bacillus, Nocardia, Arthrobacter, and Rhodococcus. Also, Actinomycete, yeast and fungal cultures were also isolated. Non-sporiferous bacteria were widely presented at all altitudes. Enzymatic activity of the isolated microorganisms and a number of pathogenicity factors present were investigated. The data on quantity and representation of culturable microorganisms and other biogenic components at altitudes up to 8000 m in Northwestern Siberia were obtained for the first time. It is a significant contribution to the study of the atmosphere of this region. The patterns of the observed biodiversity of microorganisms, associated with the sampling altitude or geographic location, should be determined infurther research.

In 2020, a unique experiment, which had ever been implemented either in the former USSR or in modern-day Russia, was carried out in the Russian Arctic by means of the Optik Tu-134 aircraft laboratory operated by IAO SB RAS. The airborne measurement campaign was conducted on September 4-17 over all seas and coastal regions of the Russian sector of the Arctic, including northern part of the Bering Sea.During the flights, in situ measurements of CO, CO2, CH4, NO, NO2, SO2, O3, aerosols, and black carbon (BC) were performed. Air samples were taken to determine organic and inorganic compounds and biological material in aerosol particles. A remote sensing of the water turbidity in the upper sea layers was conducted by means of the LOZA-2 lidar that allowed a concentration of plankton to be derived there. Spectral characteristics of the water and underlying coastal surfaces were measured using a spectroradiometer.The primary analysis of the obtained data showed that concentrations of CO, NO, NO2, SO2, O3, aerosols, and BC during the experiment were low that is typical for background regions. CO2 mixing ratios in the lowest part of the troposphere above seas were lower than aloft. As compared with coastal areas, concentration of methane over all the seas of the Arctic sector and the Bering Sea was higher.We would like to acknowledge our colleagues from the following organizations for their assistance in organizing and conducting this campaign, and in particular, Laboratoire des sciences du climat et de l'environnement and Laboratoire atmosphères, milieux, observations spatiales (France); Finnish Meteorological Institute and Institute for Atmospheric and Earth System Research, University of Helsinki (Finland); Center for Global Environmental Research at the National Institute for Environmental Studies (Japan); the National Oceanic and Atmospheric Administration, US Department of Commerce (USA); Max-Planck-Institute for Biochemistry (Germany); and University of Reading (UK).

The detection of influenza A virions with a nanoribbon detector (NR detector) has been demonstrated. Chips for the detector have been fabricated based on silicon-on-insulator nanoribbon structures (SOI nanoribbon chip), using a complementary metal-oxide-semiconductor (CMOS)-compatible technology—by means of gas-phase etching and standard optical photolithography. The surface of the SOI nanoribbon chip contains a matrix of 10 nanoribbon (NR) sensor elements. SOI nanoribbon chips of n-type conductance have been used for this study. For biospecific detection of target particles, antibodies against influenza virus have been covalently immobilized onto NRs. Influenza A virus detection was performed by real-time registration of the source-drain current through the NRs. The detection of the target viral particles was carried out in buffer solutions at the target particles concentration within the range from 107 to 103 viral particles per milliliter (VP/mL). The lowest detectable concentration of the target viral particles was 6 × 10−16 M (corresponding to 104 VP/mL). The use of solutions containing ~109 to 1010 VP/mL resulted in saturation of the sensor surface with the target virions. In the saturation mode, detection was impossible.

The presented results indicate virus-like particles of the coronavirus (CVP) using a nanowire (NW) biosensor based on silicon-on-insulator technology. In the experiment, we used suspensions of CVP and of specific antibodies to the virus. Measurements of the current value of the field-effect transistor before and after the introduction of the CVP on the surface of the nanowire were performed. Results showed antibody + CVP complexes on the phase section with the surface of the nanowire modulate the current of the field-effect transistor; CVP has an electrically positive charge on the phase section “nanowire surface-viral suspension»; antibody + CVP complexes have an electrically negative charge on the phase section “nanowire surface-viral suspension”; the sensitivity of the biosensor is made up of 10−18 M; the time display was 200–300 s.

One of the most important components of atmospheric aerosols are microorganisms. Therefore, it is necessary to assess the hazard to humans, both from individual microorganisms which are present in atmospheric bioaerosols as well as from their pool. An approach for determining the hazard of bacteria and yeasts found in atmospheric bioaerosols for humans has previously been proposed. The purpose of this paper is to compare our results for 2006&ndash, 2008 with the results of studies obtained in 2012&ndash, 2016 to identify changes in the characteristics of bioaerosols occurring over a decade in the south of Western Siberia. Experimental data on the growth, morphological and biochemical properties of bacteria and yeasts were determined for each isolate found in bioaerosol samples. The integral indices of the hazards of bacteria and yeast for humans were constructed for each isolate based on experimentally determined isolate characteristics according to the approach developed by authors in 2008. Data analysis of two datasets showed that hazard to humans of culturable microorganisms in the atmospheric aerosol in the south of Western Siberia has not changed significantly for 10 years (trends are undistinguishable from zero with a confidence level of more than 95%) despite a noticeable decrease in the average annual number of culturable microorganisms per cubic meter (6&ndash, 10 times for 10 years).

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.

We present the experimental results of measurements of the masses of a separately observed erythrocyte and a latex particle placed in a variable electric field. We show that the experimentally measured and theoretically computed masses of reference latex particles are in good agreement.

The experimental method is described and the measurement results of the value of polarizability of erythrocytes and latex particles in a non-uniform alternating electric field are presented. The results show that the values of experimentally measured and theoretically calculated polarizablity values of latex particles are in good agreement.

The recent outbreak of coronavirus disease caused by the respiratory syndrome coronavirus 2 (SARS-CoV-2) has highlighted the urgent need to develop fast and highly sensitive analytical tools and diagnostic devices to detect and study of the fundamental properties viruses and their nucleic acid and protein components [1]. Silicon-on-insulator field-effect transistors (SOI-FETs) based sensors provide the versatile platform for direct detection of biological species as excellent electrical signal converters. These devices have demonstrated applications for label-free, ultra-sensitive, and selective real-time detection of a wide range of biological species, including nucleic acids, proteins and viruses in either single-element or multiplexed formats [2-5]. Dielectrophoresis (DEP) and electro-hydrodynamic techniques are well known as the methods of selection and delivery of analytes to overcome limitations of diffusive transport to sensor elements without additional processing or labeling steps [6]. The aim of this study was to investigate the features of the behavior of the viruses when they are indicated by SOI-FET sensors with DEF-control. For this, SOI-FET sensors with lateral DEP-electrodes and multichannel sensors, for comparison, were used. Top-down technology with using optical lithography was applied for sensor fabrication. Devices manufacturing details are described elsewhere [3]. As an analyte, we used nuclear polyhedrosis viruses (NPVs), coronavirus virus-like particles (CVP) and suspension of specific antibodies to the virus created in the Federal research center of Virology and biotechnology "Vector" of Rospotrebnadzor. The results showed that the sensors used in the study provide the subatomolar level of virus detection. DEP-concentration of viruses increase the response of the sensors by factors of 2 to 9 (compared to the response of sensors without DEP control) and allows the false positives can be eliminated. NPVs lose their mobility with prolonged exposure to an alternating field in the sub-MHz range. The DEP-concentration of CVP leads to the formation of crystal-like structures (Fig.1). This study was supported by grant no. 18-29-02091 of the Russian Foundation for Basic Research. Sample preparation of biological materials was done within the framework of the State Task of Rospotrebnadzor. Referencies: WHO Director-General's opening remarks at the media briefing on COVID-19 – 23 April 2021 23 апреля 2021 г.https://www.who.int/director-general/speeches/detail/who-director-general-s-opening-remarks-at-the-media-briefing-on-covid-19-23-april-2021. Patolsky F., Zheng G., Hayden O., Lakadamyali M., Zhuang X., Lieber C. M. Electrical detection of single viruses // Proc. Natl. Acad. Sci. 2004, v. 101. p. 14017-14022. O. V. Naumova, V. M. Generalov, E. G. Zaitseva, A. V. Latyshev, A. L. Aseev, S. A. Pyankov, I. V. Kolosov, G. G. Ananko, A. P. Agafonov, E. V. Gavrilova, R. A. Maksyutov, and A. S. Safatov. Biosensors Based on Soi Nanowire Transistors for Biomedicine and Virusology. Russian Microelectronics, 2021, v. 50, N3, p. 137–145. Ivanov Y.D., Pleshakova T.O., Kozlov A.F., Malsagova K.A., Krohin N.V., Shumyantseva V.V., Shumov I.D., Popov V.P., Naumova O.V., Fomin B.I., Nasimov D.A., Aseev A.L., Archakov A.I. SOI nanowire for the high-sensitive detection of HBsAg and a-fetoprotein. Lab Chip. 2012, v. 12, p. 5104-5111. Dmitrienko E., Naumova O., Fomin B., Kupryushkin M., Volkova A., Amirkhanov N., Semenov D., Pyshnaya I., Pyshnyi D. Surface modification of SOI FET sensors for label-free and specific detection of short RNA analyte. Nanomedicine 2016, v. 11, N 16, p. 2073-2082. Lee S., Roh S.M., Lee E., Park Y., Lee B.C., Kwon Y., Kim H.J., Kim J. Applications of converged various forces for detection of biomolecules and novelty of dielectrophoretic force in the applications(Review). Sensors, 2020, v.20, p.3242. Fig.1 – Optical image of sensor with lateral DEP electrodes after CVP detection. In the left - CVP organized in crystal-like structures under DEP-concentration, in the right (green dots on dark field) - viruses with luminescent labels. S - source, D - drain. G1, G2 - lateral DEP electrodes. Figure 1

Theoretical analysis of the relative error of measurement of polarizability of cells using the dielectrophoresis method is described. Information about the magnitude of error ensures objective evaluation of the disease dynamics and the effectiveness of treatment.

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.

Nonlinear polarizability of erythrocytes in non-uniform alternating electric field (NUAEF) was proved theoretically and experimentally by dielectrophoresis method. The paper presents experimental evidence of the nonlinear polarizability of erythrocytes in the non-uniform alternating electric field. The rotation of erythrocyte around its own axis at more than one revolution per second in the non-uniform alternating electric field in the frequency range and the electric field intensity is the evidence of its nonlinear polarizability. The theoretical analysis of the density of electric charges capable of overcoming the membrane potential was carried out on the basis of statistical mechanics, the thermal equilibrium in which the particle stays. The nonlinear polarizability of the erythrocyte emerges if the voltage on the membrane exceeds , which was theoretically proved. The alternating electric field from the donor erythrocyte with the amplitude exceeding forms the constant component of the current in the cytoplasm of the recipient erythrocyte whose energy can be considered as a signal one. The nonlinear equivalent electric circuit of the cell was proposed.

A brief literature review of the foundations of the theory of dielectrophoresis and electrorotation of a cell in an electric field, and the extent of their practical application in the field of medicine, microbiology, virology, biophysics are provided. Primary concerns of metrological provision of traceability of measurements in the field of dielectrophoresis and rotation of the cell as per Federal Law No. 102-FZ are grounded.

This study presents results of the study of infectivity of avian influenza virus (AIV) A subtype H5N1 strains isolated from agricultural birds across the territory of the Russian Federation and CIS countries. The results of the susceptibility of chickens to the AIV isolates delivered by the aerosol route and the dissemination of the virus in the organs of infected birds are presented. As was observed, the sensitivity of birds to AIV by the aerosol route of infection is 30 times higher than by intranasal route, 500 times higher than by the oral route and 10000 times higher than by the intragastric route of infection, which is indicative of higher permissivity of respiratory organs to AIV. The highest titres of AIV A subtype H5N1(A/Chicken/Kurgan/05/2005 strain) in aerosol-infected chickens were found in nasal cavity mucosa, lungs, cloaca, serum and kidney, where viable virus accumulation was detected by 18h post-infection (p.i.). The highest virus titres were observed 54h p.i. in lungs, serum and kidney, reaching the value of 8.16 lg EID50 /g(ml) in the lungs. The results showed that birds infected by the aerosol route developed higher titres of virus than those infected by other routes.

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.

Air disinfection from bacteria and viruses by means of photocatalytic oxidation is investigated with microorganisms loaded over photocatalysts' films from aerosols. Deposition method and equipment have been developed to load Mycobacterium smegmatis , Bacillus thuringiensis , vaccinia virus, and influenza A (H3N2) virus on slides with undoped TiO(2) and platinized sulfated TiO(2) (Pt/TiO(2)). Inactivation dynamics was measured under UVA irradiation and in the dark. About 90% inactivation is reached in 30 min irradiation on TiO(2) and from 90 to 99.8% on Pt/TiO(2). The first-order inactivation rate coefficient ranged from 0.18 to 0.03 min(-1), over Pt/TiO(2) being higher than on TiO(2) for all microorganisms except Bacillus thuringiensis. The photocatalytic mineralization of Bacillus thuringiensis was performed on TiO(2) and Pt/TiO(2) with different photocatalyst and microorganism loadings. Completeness of mineralization depended on the TiO(2) to bacteria mass ratio. The rate of the photocatalytic carbon dioxide production grows with both the cell mass increase and the photocatalyst mass increase. Pt/TiO(2) showed increased rate of mineralization as well as of the inactivation likely due to a better charge carrier separation in the doped semiconductor photocatalyst. The results demonstrate that photocatalytic filters with deposited TiO(2) or Pt/TiO(2) are able to inactivate aerosol microorganisms and completely decompose them into inorganic products and Pt/TiO(2) provides higher disinfection and mineralization rates.

This paper describes a new method for precise determination of viral aerosol lethal dose (ALD 50 ) and reports the results obtained for birds exposed by H5N1 Avian influenza A strain under controlled laboratory conditions. The reported method utilizes our recently developed personal bioaerosol sampler capable of monitoring viable virus concentration in the ambient air. Up to six laboratory animals could be located in a specially designed aerosol chamber and exposed in parallel by an airborne strain of interest to generate the amount of data sufficient for representative statistical analysis. A concentration of viable airborne virus was measured by the personal aerosol samplers directly in the breathing zone of each particular bird. The results show a very low inter-sampler variation used for each particular run, which was confirmed by a single factor ANOVA test undertaken for all six personal samplers involved in each experiment. As was shown, the difference in amount of viruses collected by all samplers during each particular run was not statistically significant. It was found that the ALD 50 for approximately 400-g birds exposed to H5N1 Avian influenza A strain A/Chicken/Suzdalka/Nov-11/2005 was around 26.5 FFU (focus forming units).

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.

A new personal bioaerosol sampler, which was found suitable for continuous long-term (up to 8 h) monitoring of airborne bacteria, fungi, and viruses, was recently developed. A range of investigations under controlled laboratory conditions verified the performance of the device for both stress sensitive and robust viral particles. To decrease the detection time, the next step of the technique development was related to utilization of the sampler in combination with polymerase chain reaction (PCR) technology in the laboratory. The combined device was found to be fully feasible with the corresponding decrease of the detection time from a few days to 2.5 h. In addition, the results for targeted microorganisms were not affected by background biological particles and cross-reaction was not observed. The current study is the first trial to use the new combined device, i. e., sampler-conventional PCR device, for monitoring airborne viruses in the field. The monitoring procedures were performed in hospital infection wards with patients suffering from mumps and measles diseases to detect the corresponding disease causing viruses in the ambient air. The results for the existence of the airborne viruses were obtained for both strains. A simple procedure is also suggested for enumeration of microbial contamination in the ambient air.

Multi-year monitoring of atmospheric bioaerosol in Southwestern Siberia revealed the presence of a large number of various culturable microorganisms. It is known that viable microorganisms can cause directly or provoke different human diseases. It's very difficult to evaluate the danger represented by each microorganism to man directly. Therefore, a relatively simple method is required for evaluation of potential danger represented to man by the whole assembly of culturable microorganisms in an atmospheric aerosol sample. For bacteria, the method can be based on a number of individual characteristics of each microorganism determined in the course of biochemical and other test required for identification of the detected bacterium, and a number of other tests. It is proposed to classify the measured individual characteristics of bacteria under four groups of indices responsible for: (i) potential pathogenicity for man; (ii) the numbers of bacteria in the sample; (iii) resistance to unfavorable environmental factors; (iv) drug resistance of bacteria. Each of four groups of indices is numerically evaluated by a certain integral index, which quantitatively reflects the contribution of experimentally determined characteristics of bacteria. Expert evaluation of the contribution of each characteristic of microorganisms to the corresponding group of indices is performed. The generalized index of potential danger of culturable bacteria in atmospheric aerosols for human health is presented as the product of four integral indices summarizing the normalized individual integral indices for all bacteria detected in the sample. The work presents the results of measuring the variations of all the above indices for atmospheric air samples collected during one year.

The aim of this work was to assess the potential of some physical and chemical methods for studying erythrocytes and blood serum in gastroenterological practice by the example of colorectal cancer (CC).A total of 26 persons with various stages of colorectal cancer and 16 healthy (control group) were examined. Parameters of erythrocytes and blood serum were investigated by light microscopy, dielectrophoresis in a non-uniform alternating electric field (DEF in NUAEF), terahertz spectroscopy, ellipsometry, Raman-spectroscopy.Polymorphism of erythrocytes, rigidity, viscosity, indexes of aggregation and destruction were significantly higher in patients with CC and polarizability, amplitude of erythrocyte deformation in NUAEF being lower than those in the controls. The study of erythrocytes by terahertz spectroscopy revealed the low levels of amplitude transmittance over the whole frequency range in CC patients compared to the controls. The increasing of refractive index, degree of heterogeneity of thin films obtained from the serum in CC patients were observed in considering the ellipsometric parameters. We found a significant increasing of the concentration of antigens to CD24 at the early stage of the disease. The areas of some peaks in Raman spectra were significantly lower in patients with CC compared to the healthy ones, it is possible due to a carotin deficiency. Most of the studied parameters were correlated with the stage of the disease. A set of optical methods for studying blood serum compared with those of histology and radiological methods of diagnosis showed their high sensitivity and specificity, positive and negative predictive value (80 % and above).The obtained results of the pilot study demonstrate the prospects of using physical and chemical methods of research of erythrocytes and blood serum for early diagnosis, stage of disease and monitoring the effectiveness of treatment of CC.

A new personal sampler had been previously developed and verified for monitoring of viable airborne viruses. The aims of this project were to investigate a possibility of the utilization of the polymerase chain reaction (PCR) method to speed up the time consuming analytical procedures and to evaluate a lower detection limit of the combined (sampler-PCR) device. Tenfold serial dilutions of the initial suspension of the Vaccinia virus were aerosolized in the chamber and airborne viruses were monitored by two simultaneously operating samplers. The results of monitoring were successfully obtained by a standard plaque assay (live microbes) and by the PCR method (total DNA). The corresponding calculations to identify the minimal detectable concentration in the ambient air were then performed. It was found that the minimal detectable concentration of airborne viruses in the ambient air depends on the sampling time. As demonstrated, such concentration should be at least 125×103 PFU m−3 for a sampling time of as short as 1 min. The detectable concentration decreases with the increase of the sampling time and reaches 25×103 and 10×103 PFU m−3 for 5 and 12.5 min of sampling respectively.

A novel bioaerosol sampling technique, which utilizes the bubbling process in the collection fluid, has recently been developed and found feasible for a long-term personal sampling of airborne bacteria and fungal spores as it maintained high physical collection efficiency and high microbial recovery rate for robust and stress-sensitive microorganisms. Further tests have shown that the new technique also has potential to collect viable airborne viruses, particularly when utilized for a short-term sampling of robust strains. As the short-term sampling has a limited application for assessing personal exposure in bioaerosol-contaminated environments, the present study was undertaken to investigate the feasibility of the “bubbler” for a long-term monitoring of viable airborne viruses. Liquid droplets containing Vaccinia virions (that simulate Variola, a causative agent of smallpox) were aerosolized with a Collison nebulizer into a 400-liter test chamber, from which the droplets were collected by three identica...

The State Research Center of Virology and Biotechnology “Vector” and the Institute of Optics SB RAS are performing systematic study of tropospheric bioaerosols in the South of Western Siberia. The work summarizes the results of analysis of some physical characteristics of the data array on bioaerosol concentration obtained with an airplane laboratory at the altitudes of 0.5, 1, 1.5, 2, 3, 4, 5.5 and 7 km. The flights were performed during the last 10 days of each month in 1999–2003. It was shown that the concentration of total protein aerosols obeyed the laws of continual statistics, and the concentration of culturable microorganism aerosols obeyed the laws of discrete statistics. The analysis of correlation coefficients and cross correlation of bioaerosol concentration fields was performed. Wavelet analysis of the data showed that variations of tropospheric bioaerosol concentration were mainly determined by typical seasonal processes with periods of 12, 6, 4 and 8–9 months. Seasonal variations cause approximately 80% of the total dispersion of variations of total protein concentration, and the amplitudes of variations of culturable microorganism concentration are small as compared with the constant component. Harmonic analysis of bioaerosol concentration fields was performed. Harmonics that are significant in wavelet spectra for all time series were taken for the approximation of the series. It was revealed that four-month periodicity was internal and was caused by a wave spreading from above with a vertical rate of about 4 km/month.

This research investigates a promising antiviral compound based on polyprenols from Siberian silver fir (Abies sibirica). The physico-chemical characteristics of a preparation developed in aerosol form and an estimation of its protective efficacy against aerosol challenge of laboratory animals are presented. It is shown that (1) by using a simple ultrasonic disperser one can obtain aerosol of three formulations studied with about 70% of its mass accumulated in the size range below 1.8 microm; (2) 40-100% of aerosol particles contain preparation for different formulations; (3) after delivering under specified schedules, the preparations as developed can protect up to 100% of mice against 5 LD(50) of influenza A/Aichi/2/68 (H3N2) virus aerosol infection. Animals inhaled twice the preparation doses (which were 100 times lower than injection ones of the same efficacy) and did not exceed 10 microg/mouse. It was shown that the mode of action of this immunomodulating preparation was nonspecific stimulation of immune cells' various activities.

A new personal bioaerosol sampler has recently been developed and evaluated for sampling of viable airborne bacteria and fungi under controlled laboratory conditions and in the field. The operational principle of the device is based on the passage of air through porous medium immersed in liquid. This process leads to the formation of bubbles within the filter as the carrier gas passes through and thus provides effective mechanisms for aerosol removal. As demonstrated in previous studies, the culturability of sampled bacterium and fungi remained high for the entire 8-h sampling period. The present study is the first step of the evaluation of the new sampler for monitoring of viable airborne viruses. It focuses on the investigation of the inactivation rate of viruses in the bubbling process during 4 h of continuous operation. Four microbes were used in this study, influenza, measles, mumps, and vaccinia viruses. It was found that the use of distilled water as the collection fluid was associated with a relatively high decay rate. A significant improvement was achieved by utilizing virus maintenance fluid prepared by using Hank's solution with appropriate additives. The survival rates of the influenza, measles, and mumps viruses were increased by 1.4 log, 0.83 log, and 0.82 log, respectively, after the first hour of operation compared to bubbling through the sterile water. The same trend was observed throughout the entire 4-h experiment. There was no significant difference observed only for the robust vaccinia virus.

While various sampling methods exist for collecting and enumerating airborne bacteria and fungi, no credible methodology has yet been developed for airborne viruses. A new sampling method for monitoring the personal exposure to bioaerosol particles has recently been developed and evaluated with bacteria and fungi. In this method, bacterial/fungal aerosol is aspirated and transported through a porous medium, which is submerged into a liquid layer. As the air is split into numerous bubbles, the particles are scavenged by these bubbles and effectively removed. The current feasibility study was initiated to evaluate the efficiency of the new personal sampler prototype ("bubbler") with airborne viable viruses. Two common viral strains, Influenza (stress-sensitive) and Vaccinia (robust), were aerosolized in the test chamber and collected by two identical "bubblers" that operated simultaneously for a duration of upto 5 min. A virus maintenance liquid, proven to be the optimum collecting environment for the test organisms, was used as a collection fluid. After sampling, the collecting fluid was analyzed and the viral recovery rate was determined. The overall recovery (affected not only by the sampling but also by the aerosolization and the aerosol transport) was 20% for Influenza virus and 89% for Vaccinia virus. The new sampling method was found feasible for the collection and enumeration of robust airborne viruses.

) appear to be highly virulent for chickens. The chance of AFV infection of chickens in case of intranasal challenge is 20 times as great as in the case of peroral one, and 300 times as great as in the case of intragastral one, which bears evidence to higher sensitivity to AFV of the tissues of avian respiratory organs, in comparison with the tissues of gastro-intestinal tract. Therewith, primary target organ for virus in intranasal infected birds is their respiratory channel (mucous membrane of the nasal cavity in particular). Registered is the possibility of existence of fecal-nasal AFV transfer mechanism in chickens.