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Full list of authors: Jorstad, S. G.; Marscher, A. P.; Raiteri, C. M.; Villata, M.; Weaver, Z. R.; Zhang, H.; Dong, L.; Gomez, J. L.; Perel, M., V; Savchenko, S. S.; Larionov, V. M.; Carosati, D.; Chen, W. P.; Kurtanidze, O. M.; Marchini, A.; Matsumoto, K.; Mortari, F.; Aceti, P.; Acosta-Pulido, J. A.; Andreeva, T.; Apolonio, G.; Arena, C.; Arkharov, A.; Bachev, R.; Bonnoli, G.; Borman, G. A.; Bozhilov, V; Carnerero, M., I; Damljanovic, G.; Ehgamberdiev, S. A.; Elsasser, D.; Frasca, A.; Gabellini, D.; Grishina, T. S.; Gupta, A. C.; Hagen-Thorn, V. A.; Hallum, M. K.; Hart, M.; Hasuda, K.; Hemrich, F.; Hsiao, H. Y.; Ibryamov, S.; Irsmambetova, T. R.; Ivanov, D., V; Joner, M. D.; Kimeridze, G. N.; Klimanov, S. A.; Knoett, J.; Kopatskaya, E. N.; Kurtanidze, S. O.; Kurtenkov, A.; Kuutma, T.; Larionova, E. G.; Leonini, S.; Lin, H. C.; Lorey, C.; Mannheim, K.; Marino, G.; Minev, M.; Mirzaqulov, D. O.; Morozova, D. A.; Nikiforova, A. A.; Nikolashvili, M. G.; Ovcharov, E.; Papini, R.; Pursimo, T.; Rahimov, I; Reinhart, D.; Sakamoto, T.; Salvaggio, F.; Semkov, E.; Shakhovskoy, D. N.; Sigua, L. A.; Steineke, R.; Stojanovic, M.; Strigachev, A.; Troitskaya, Y., V; Troitskiy, I. S.; Tsai, A.; Valcheva, A.; Vasilyev, A. A.; Vince, O.; Waller, L.; Zaharieva, E.; Chatterjee, R., Blazars are active galactic nuclei (AGN) with relativistic jets whose non-thermal radiation is extremely variable on various timescales1,2,3. This variability seems mostly random, although some quasi-periodic oscillations (QPOs), implying systematic processes, have been reported in blazars and other AGN. QPOs with timescales of days or hours are especially rare4 in AGN and their nature is highly debated, explained by emitting plasma moving helically inside the jet5, plasma instabilities6,7 or orbital motion in an accretion disc7,8. Here we report results of intense optical and γ-ray flux monitoring of BL Lacertae (BL Lac) during a dramatic outburst in 2020 (ref. 9). BL Lac, the prototype of a subclass of blazars10, is powered by a 1.7 × 108 MSun (ref. 11) black hole in an elliptical galaxy (distance = 313 megaparsecs (ref. 12)). Our observations show QPOs of optical flux and linear polarization, and γ-ray flux, with cycles as short as approximately 13 h during the highest state of the outburst. The QPO properties match the expectations of current-driven kink instabilities6 near a recollimation shock about 5 parsecs (pc) from the black hole in the wake of an apparent superluminal feature moving down the jet. Such a kink is apparent in a microwave Very Long Baseline Array (VLBA) image. © 2022 Springer Nature Limited., The research reported here is based on work supported in part by US National Science Foundation grants AST-2108622 and AST-2107806, and NASA Fermi GI grants 80NSSC20K1567, 80NSSC21K1917 and 80NSSC21K1951; by Shota Rustaveli National Science Foundation of Georgia under contract FR-19-6174; by the Bulgarian National Science Fund of the Ministry of Education and Science under grants DN 18-10/2017, DN 18-13/2017, KP-06-H28/3 (2018), KP-06-H38/4 (2019) and KP-06-KITAJ/2 (2020), and by National RI Roadmap Project D01-383/18.12.2020 of the Ministry of Education and Science of the Republic of Bulgaria; by JSPS KAKENHI grant #19K03930 of Japan; by the Ministry of Education, Science and Technological Development of the Republic of Serbia (contract 451-03-9/2021-14/200002) and observing grant support from the Institute of Astronomy and Rozhen NAO BAS through the bilateral joint research project ‘Gaia Celestial Reference Frame (CRF) and fast variable astronomical objects’; by the Agenzia Spaziale Italiana (ASI) through contracts I/037/08/0, I/058/10/0, 2014-025-R.0, 2014-025-R.1.2015 and 2018-24-HH.0 to the Italian Istituto Nazionale di Astrofisica (INAF). H.Z. is supported by the NASA Postdoctoral Program at Goddard Space Flight Center, administered by ORAU. M.V.P. is partially supported by the Russian Foundation for Basic Research grant 20-02-00490. G.B. acknowledges support from the State Agency for Research of the Spanish MCIU through the ‘Center of Excellence Severo Ochoa’ award to the Instituto de Astrofísica de Andalucía (SEV-2017-0709) and from the Spanish ‘Ministerio de Ciencia e Innovacíon’ (MICINN) through grant PID2019-107847RB-C44. M.D.J. thanks the Brigham Young University Department of Physics and Astronomy for continued support of the extragalactic monitoring programme under way at the West Mountain Observatory. R.C. thanks ISRO for support under the AstroSat archival data utilization programme and BRNS for support through a project grant (sanction no. 57/14/10/2019-BRNS). The measurements at the Hans Haffner Observatory, Hettstadt, Germany, were supported by Baader Planetarium, Mammendorf, Germany. This study was based (in part) on observations conducted using the 1.8-m Perkins Telescope Observatory (PTO) in Arizona, USA, which is owned and operated by Boston University. These results made use of the Lowell Discovery Telescope (LDT) at Lowell Observatory. Lowell Observatory is a private, non-profit institution dedicated to astrophysical research and public appreciation of astronomy, and operates the LDT in partnership with Boston University, the University of Maryland and the University of Toledo. This paper is partly based on observations made with the IAC-80 operated on the island of Tenerife by the Instituto de Astrofisica de Canarias in the Spanish Observatorio del Teide and on observations made with the LCOGT telescopes, one of whose nodes is located at the Observatorios de Canarias del IAC on the island of Tenerife in the Observatorio del Teide. This paper is partly based on observations made with the Nordic Optical Telescope, owned in collaboration by the University of Turku and Aarhus University, and operated jointly by Aarhus University, the University of Turku and the University of Oslo, representing Denmark, Finland and Norway, the University of Iceland and Stockholm University at the Observatorio del Roque de los Muchachos, La Palma, Spain, of the Instituto de Astrofisica de Canarias. The VLBA is an instrument of the NRAO, USA. The NRAO is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc.

We present a new version of our analytical model of the spatial interstellar extinction variations within the nearest kiloparsec. This model treats the 3D dust distribution as a superposition of three overlapping layers: (1) the layer along the Galactic midplane, (2) the layer in the Gould Belt, and (3) the layer passing through the Cepheus and Chamaeleon dust cloud complexes. In each layer the dust density decreases exponentially with increasing distance from the midplane of the layer. In addition, there are sinusoidal longitudinal extinction variations along the midplane of each layer. We have found the most probable values of 29 parameters of our model using four data sets: the 3D stellar reddening maps by Gontcharov (2017), Lallement et al. (2019), and Green et al. (2019) and the extinctions inferred by Anders et al. (2022) for 993291 giants from the Gaia EDR3. All of the data give similar estimates of the model parameters. The extinction for a star or a point in space is predicted by our model with an accuracy from $\sigma(A_\mathrm{V})=0.07$ to 0.37 for high and low Galactic latitudes, respectively. The natural fluctuations of the dust medium dominate in these values. When ignoring the fluctuations of the medium, the average extinction for an extended object (a galaxy, a star cluster, a dust cloud) or a small region of space is predicted by our model with an accuracy from $\sigma(A_\mathrm{V})=0.04$ to 0.15 for high and low Galactic latitudes, respectively. Green et al. (2019) and Anders et al. (2022) give in unison an estimate of $A_\mathrm{V}=0.12^m$ for the extinction at high latitudes across the whole Galactic dust half-layer above or below the Sun with the natural fluctuations of the medium $\sigma(A_\mathrm{V})=0.06^m$. Our model is a step to explain how a substantial amount of dust ended up far from the Galactic midplane., Comment: Published in Astronomy Letters, 2022, 48, 578-600

In 2021 BL Lacertae underwent an extraordinary activity phase, which was intensively followed by the Whole Earth Blazar Telescope (WEBT) Collaboration. We present the WEBT optical data in the BVRI bands acquired at 36 observatories around the world. In mid 2021 the source showed its historical maximum, with R = 11.14. The light curves display many episodes of intraday variability, whose amplitude increases with source brightness, in agreement with a geometrical interpretation of the long-term flux behaviour. This is also supported by the long-term spectral variability, with an almost achromatic trend with brightness. In contrast, short-term variations are found to be strongly chromatic and are ascribed to energetic processes in the jet. We also analyse the optical polarimetric behaviour, finding evidence of a strong correlation between the intrinsic fast variations in flux density and those in polarisation degree, with a time delay of about 13 h. This suggests a common physical origin. The overall behaviour of the source can be interpreted as the result of two mechanisms: variability on time scales greater than several days is likely produced by orientation effects, while either shock waves propagating in the jet, or magnetic reconnection, possibly induced by kink instabilities in the jet, can explain variability on shorter time scales. The latter scenario could also account for the appearance of quasi-periodic oscillations, with periods from a few days to a few hours, during outbursts, when the jet is more closely aligned with our line of sight and the time scales are shortened by relativistic effects., Comment: 15 pages, 16 figures, submitted to MNRAS

In this paper optical properties of microcrystalline HfO2 powder are investigated. X-ray diffraction and Raman spectroscopy were used to determine that the studied samples are in monoclinic phase. Based on the analysis of the diffuse reflectance spectra and applying Kubelka-Munk formalism we evaluated the indirect bandgap value Eg = 5.34 ± 0.05 eV. The calculated value is in agreement with independent data for HfO2 thin films synthesized by various methods. The paper is based on the materials of the report presented at the first Russian scientific confererence with the participation of the international community "YENISEI PHOTONICS – 2020"

Thermal quenching is one of the essential factors in reducing the efficiency of radiative processes in luminophores of various nature. The emission activity of low dimensional structures is influenced also by multiplicity of parameters that are related to synthesis processes, treatment regimes, etc. In the present work, we have investigated the temperature dependence of photoluminescence caused by exciton and defect-related transitions in ensembles of biocompatible InP/ZnS core/shell nanocrystals with an average size of 2.1 and 2.3 nm. The spread in the positions of energy levels is shown to be due to size distribution of quantum dots in the ensembles under study. For a quantitative analysis of the experimental data, we have proposed a band model accounting for the Gaussian distribution of the thermally activated barriers in the photoluminescence quenching processes. The model offers the thermal escape of an electrons from the core into the shell as the main mechanism for non-radiative decay of excitons. In turn, the quenching of defect-related emission is predominantly brought about through the emptying of the hole capture centers based on dangling phosphorus bonds. We have revealed the correlation between size distributions of quantum dots and scatter of the activation energy of exciton luminescence quenching. The developed approach will give further the possibility to optimize technological regimes and methods for band engineering of indium phosphide-based type-I quantum dots., Comment: 24 pages, 6 figures, 3 tables, 79 references. Keywords: quantum dots, core/shell, exciton and defect states, luminescence thermal quenching, inhomogeneous broadening, activation energy distribution

The chapter summarizes research results on temperature evolution of optical absorption spectra in a wide temperature range of 6.5–296 K for colloidal core/shell InP/ZnS quantum dot ensembles with a different size distribution. Exciton–optical transition energies in the InP core and ZnS shell were determined by the second-order derivative spectrophotometry. Numerical analysis within the frame of linear exciton–phonon coupling showed that the shifts of the observed spectral maxima with temperature were due to the interaction of excited states with longitudinal acoustic vibrations. It was established that the half-width of the spectral bands remained unchanged, which indicated the inhomogeneous broadening effect and a high degree of static disorder in the ensembles under study. The semi-phenomenological model was proposed that took into account the effects of the exciton–phonon interaction and allowed one to analyze the influence of the static and dynamic types of atomic disorder on behavior of optical absorption spectra in InP/ZnS quantum dots under temperature variation.

Optical absorption spectra of HfO2 thin film synthesized by ion beam sputtering deposition technique were studied. Interference effects were used to determine film thickness, which was d=288 nm, and to calculate dispersion curves for refractive index, extinction coefficient and both real and imaginary parts of dielectric permittivity. Optical data near intrinsic absorption edge were analyzed to estimate the energy gap of Eg = 5.40±0.05 eV in the hafnia film under research.

Photoluminescence (PL) thermal quenching of InP/ZnS core/shell nanocrystals of 4.2 (QD-1) and 4.6 (QD-2) nm in diameter is investigated in the temperature range of 6.5-296 K. Observed PL spectra are found to originate from exciton and defect-related transitions. Temperature behavior of the emission bands indicates effects of inhomogeneous broadening due to distributions of quantum dots parameters in the ensembles. PL thermal quenching analysis unveils two non-radiative relaxation channels for each band in both samples. Activation energies of 130 and 119 meV in QD-1 and QD-2, correspondingly, for the exciton band can be assigned to the bright-bright splitting of the exciton fine structure. © Published under licence by IOP Publishing Ltd. Departamento Administrativo de Ciencia, Tecnología e Innovación (COLCIENCIAS): 727-2015 Departamento Administrativo de Ciencia, Tecnología e Innovación (COLCIENCIAS) We gratefully acknowledge the financial support received from the Departamento Administrativo de Ciencia, Tecnología e Innovación, Colciencias, Colombia, through Convocatoria No. 727-2015. The authors would also like to thank the administrative support received from the Centro de Investigación para el Desarrollo y la Innovación (CIDI) of the Universidad Pontificia Bolivariana.

The optical-absorption spectra of InP/ZnS (core/shell) quantum dots have been studied in a broad temperature range of T = 6.5–296 K. Using the second-order derivative spectrophotometry technique, the energies of optical transitions at room temperature were found to be E 1 = 2.60 ± 0.02 eV (for the first peak of excitonic absorption in the InP core) and E 2 = 4.70 ± 0.02 eV (for processes in the ZnS shell). The experimental curve of E 1(T) has been approximated for the first time in the framework of a linear model and in terms of the Fan’s formula. It is established that the temperature dependence of E 1 is determined by the interaction of excitons and longitudinal acoustic phonons with hω = 15 meV.

Aim. Determine an optimal set of the most effective methods of identification and intraspecies typing of causative agents of glanders and melioidosis. Materials and methods. Bacteriologic, immunochemical, molecular-genetic methods were used. Results. A possibility to identify collection strains of pathogenic and closely related Burkholderia in semiautomatic systems is studied. Means of detection of informative variable genome segments of the specified microorganisms were developed, methods of their genetic typing were selected. Effectiveness of application of precipitating mAbs for differentiation of Burkholderia was established. Data on diagnostic possibilities of immunoglobulins fluorescing based on monoclonal antibodies of various etiotropic directionality for detection and identification of B. mallei and B. pseudomallei are generalized. Experimental series of amplification test-systems for identification of glanders and melioidosis causative agents in real-time PCR format are created. Conclusion. A number of methods for identification and typing of glanders and melioidosis causative agents is proposed.

In this work, we have simulated the processes of broadening the first exciton band in optical absorption spectra (OA) for InP/ZnS ensembles of colloidal quantum dots (QDs). A phenomenological model has been proposed that takes into account the effects of the exciton&ndash, phonon interaction, and allows one to analyze the influence of the static and dynamic types of atomic disorder on the temperature changes in the spectral characteristics in question. To vary the degree of static disorder in the model system, we have used a parameter &delta, which characterizes the QD dispersion in size over the ensemble. We have also calculated the temperature shifts of the maxima and changes in the half-width for the exciton peaks in single nanocrystals (&delta, = 0), as well as for the integrated OA bands in the QD ensembles with different values of &delta, = 0.6&ndash, 17%. The simulation results and the OA spectra data measured for InP/ZnS nanocrystals of 2.1 nm (&delta, = 11.1%) and 2.3 nm (&delta, = 17.3%), are in good mutual agreement in the temperature range of 6.5 K&ndash, RT. It has been shown that the contribution of static disorder to the observed inhomogeneous broadening of the OA bands for the QDs at room temperature exceeds 90%. The computational experiments performed indicate that the temperature shift of the maximum for the integrated OA band coincides with that for the exciton peak in a single nanocrystal. In this case, a reliable estimate of the parameters of the fundamental exciton&ndash, phonon interaction can be made. Simultaneously, the values of the specified parameters, calculated from the temperature broadening of the OA spectra, can be significantly different from the true ones due to the effects of static atomic disorder in real QD ensembles.

Determine an optimal set of the most effective methods of identification and intraspecies typing ofcausative agents ofglanders and melioidosis. Materials andmethods. Bacteriologic, immunochemical, molecular-genetic methods were used.A possibility to identify collection strains of pathogenic and closely related Burkholderia in semiautomatic systems is studied. Means of detection of informative variable genome segments ofthe specified microorganisms were developed, methods of their genetic typing were selected. Effectiveness of application of precipitating mAbs for differentiation of Burkholderia was established. Data on diagnostic possibilities of immunoglobulins fluorescing based on monoclonal antibodies of various etiotropic directionality for detection and identification of B. mallei and B. pseudomallei are generalized. Experimental series of amplification test-systems for identification of glanders and melioidosis causative agents in real-time PCR format are created.A number of methods for identification and typing of glanders and melioidosis causative agents is proposed.

The development of methods for glanders agent genotyping is urgent due to the high pathogenicity of this microbe, lack of effective preventive measures, and threat of the use of Burkholderia mallei as a biological weapon. In this study, we propose a scheme for genotyping of B. mallei strains based on different region analysis (DFR). The choice of variable loci specific for different strains of the glanders agent was performed by analyzing the annotated whole-genome sequences of the B. mallei strains. Primers and fluorescence probes were designed for nine selected loci. The amplification conditions for different regions were optimized in two variants: with electrophoretic detection and hybridization-fluorescence detection in the strip format. DFR analysis was assessed in 14 B. mallei strains. The strain genetic profiles revealed that developed DFR-typing was characterized by a high discrimination power (Hunter–Gaston index was 0.92), reproducibility, rapidity, easy interpretation, and applicability for epidemiological surveillance of glanders.

Optical absorption (OA) and photoluminescence (PL) spectra of InP/ZnS core/shell nanocrystals with 2.3 nm average size were investigated in the temperature range of 6.5–296 K. Using second derivative spectrophotometry technique energies of the OA transitions at 296 K in quantum dot (QD) solutions and films are evaluated to be E 1 = 2.37, E 2 = 4.10 and E 3 = 4.68 eV. Temperature shifts of the E 1 and E 2 levels are found to result from interaction with effective phonons of 59 and 37 meV energies, respectively. Herewith the 370 meV half-width of the first exciton absorption peak remains constant due to the dominance of inhomogeneous broadening effects caused by QD parameters distribution. Measured PL spectra have a complex structure and can be described in 6.5–296 K range by two independent Gaussian components associated with exciton and defect-related states. In addition, Stokes shift of 320 meV is observed to decrease at T > 200 K. PL thermal quenching analysis in frame of Mott mechanism points to presence of non-radiative relaxation channel with an activation energy of 74 meV.

Currently genotyping of microorganisms is widely used in the investigation of outbreaks of infectious diseases, the implementation of epidemiological surveillance of infections and phylogenetic analysis of bacterial pathogens. Development of methods for genotyping is particularly topical for pathogens of such highly dangerous infections as plague, cholera, anthrax, brucellosis, tularemia, glanders and melioidosis, due to their high pathogenicity and contagiousness. In this overview there is presented the characteristics of different genotyping methods together with an indication of their advantages and drawbacks. There has been analyzed the frequency of the use of genotyping methods on an annual basis and in terms of the type of the causative agents of especially dangerous infections.

Development of the genotyping methods of glanders agent is urgent due to its high pathogenicity, lack of effective preventive measures and threat of the use of Burkholderia mallei as a biological weapon. In this work we proposed a scheme for the typing of the B. mallei strains based on different region analysis (DFR). The choice of variable loci differentially presented in various strains of glanders agents was performed by analyzing annotated whole-genome sequences of the B. mallei strains. Primers and fluorescence probes were designed for 9 selected loci. The amplification conditions for different regions were optimized in two variants: with electrophoretic detection and hybridization-fluorescence detection in the strip format. The possibility of applying the DFR analysis to genetic characterization of strains was assessed in 14 B. mallei strains. The genetic profiles of the studied B. mallei strains revealed that the developed DFR-typing scheme was characterized by high discrimination power (Hunter-Gaston index value was 0.92), reproducibility, rapidity, easy interpretation, and applicability for epidemiological surveillance of glanders.

Nanostructured membranes of anodic aluminum oxide (AAO) with InP/ZnS semiconductor nanocrystals deposited in pores were synthesized by electrochemical technique, physical deposition and post processing in an ultrasonic bath. Photoluminescence spectra of the samples were studied. Fluorescent properties of the quantum dots are found to be retained after the deposition. The color range is illustrated that can be covered using membranes annealed at temperatures < 900°C and by varying the concentration of the deposited InP/ZnS nanocrystals. Chromaticity coordinates and correlated color temperature for the fabricated white InP/ZnS@AAO phosphor are (0.21, 0.26) and 4115 K, respectively.

An automatized channel for measuring the resistivity in materials by the four-point probe technique was developed. The installation was based on Cascade Microtech MPS150 microprobe station, National Instruments PXIe-4143 power supply unit and PXI-4072 digital multimeter. Registration modes of surface and bulk specific resistance for samples with positioning the probes in a line or at square vertices were implemented. Measurements under corresponding modes were carried out for metallic, semiconducting bulk samples and thin coatings. Conductive and optical properties of 10, 20 and 30 nm Au layers formed on quartz glass by magnetron sputtering were investigated.

Spectral characteristics of InP/ZnS core/shell colloidal quantum dots of two different sizes (QD-1 and QD-2) were investigated. Absorption and luminescence spectra were analyzed for a series of solutions with a concentration range from 0.04 to 40 g/l. Energies of the optical transitions are evaluated. The obtained values of 2.60 eV (QD-1) and 2.38 eV (QD-2) correspond to the InP first excitonic transitions while 4.06 (QD-2) and 4.70 eV (QD-1, QD-2) are assumed to be caused by the ZnS shell absorption. Structures based on nanoporous anodic aluminum oxide (AAO) with the QDs were synthesized via an electrochemical oxidation and ultrasonic-assisted deposition. Chromaticity coordinates and correlated color temperatures for all phosphors under study were calculated. The fabrication possibilities of InP/ZnS@AAO nanostructures with tunable emission color (including the border of white region) were shown.

The shape of the arms of spiral galaxies is usually described by logarithmic spiralswith constant pitch angles, however, some galaxies display variations of the pitch angle along their spiral arms. We propose a method of determining the pitch angle of the arms in spiral galaxies based on the window Fourier analysis of their images. This method allows us not only to infer the average pitch angle, but also to obtain its value as a function of galactocentric radius. The method is implemented in the form of freely available programs.

Analysed are the methodological approaches used for identification and typing of B. mallei and B. pseudomallei . Suggested are recommendations for improvements of algorithms of laboratory diagnosis of glanders and melioidosis including wide range of biochemical, immunodiagnostic and molecular genetic methods.

For the purpose of diagnosing coccidioidomycosis by means of PCR, two pairs of primers were constructed. The first one was developed on the basis of MBP-I gene to be used for identification of two Coccidioides species, C. immitis and C. posadasii. The other pair of primers was constructed on the basis of the gene encoding immunodominant glycoprotein of the spherule outer wall (SOW gp82) to be used for identification of C. posadasii. With these primers, both highly sensitive and highly specific identification of coccidioidomycosis causative agents proved to be possible. An efficient procedure was developed for isolation of fungal DNA from soil contaminated with Coccidioides spp. arthrospores. This procedure includes guanidine thiocyanate-phenol-chloroform deproteinization followed by DNA purification by means of nucleosorption.

The glanders pathogen (Burkholderia mallei) is a highly pathogenic microorganism for humans and animals. In this article we studied the possibility of using genotyping methods for the differentiation of B. mallei strains. We characterized 14 strains of the glanders pathogen using amplification with random primers (randomly amplified polymorphic DNA, RAPD) and multilocus sequence typing (MLST). It was shown that RAPD was the best of the methods used for differentiating B. mallei strains, and it may therefore be more useful for molecular-epidemiological investigations.

The reference-center of monitoring of agents of glanders and melioidosis carried out testing of reagents kits for diagnostic of agent of melioidosis and other close-related species of Burkholderiae in vitro. At the stage of specific identification of pathogenic Burkholderiae the diagnostic possibilities of commercial and experimental kits of reagents for express- and rapid analysis were evaluated. The criteria of evaluation of diagnostic value of kits of reagents were sensitivity, specificity and time of implementation of studies. The analysis with application of mono- and multi-locus amplification systems, including real-time polymerase chain reaction permitted during 5-6 hours to implement identification and differentiation of Burkholderia pseufomallei, B. thailandensis and B. cepacia.

Analysis of genetic heterogeneity of Pseudomonas aeruginosa strains isolated in and out of hospitals.To study the genetic diversity of 36 strains of P. aeruginosa plasmid analysis, random amplified polymorphic DNA (RAPD) technique as well as polymerase chain reaction for detection of virulence genes algD, lasB, toxA, plcH, plcN, exoS, nan1, and nan2.Epidemically important strains were found in different ecological niches. It was shown that these virulence factors could play important roles in pathogenesis of infection.RAPD technique was effective for analysis of P. aeruginosa isolates. Number of studied typing bands differed between related isolates for each random primer.

Two pairs of primers for diagnosis of coccidioidomycosis using the method of PCR were constructed. One pair was used for identification of the two species of Coccidioides (C. immitis and C. posadasil) on the basis of MBP-1 gene. The other pair was chosen on the basis of SOWgp82 gene, which encodes an immunodominant, spherule outer wall glycoprotein for detecting only C. posadasii. The used primers allowed the agents of coccidioidomycosis to be detected using PCR with high sensitivity and specificity. The effective method of isolation of fungus DNA from soil contaminated with arthroconidia of Coccidioides spp. was developed. It includes guanidinthiocyanate-phenol-chloroform deproteinization followed by DNA purification using nuclear sorption.

Burkholderia mallei is highly pathogenic microorganism for both humans and animals. In this work, the possibility of the use of the genotyping method for differentiation between strains of B. mallei was studied. A collection of 14 isolates of B. mallei was characterized using randomly amplified polymorphic DNA (RAPD) and multilocus sequence typing (MLST). RAPD was the best method used for detecting strain differences of B. mallei. It was suggested that this method would be an increasingly useful molecular epidemiological tool.