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The sensitivity, specificity and reproducibility of molecular genetic methods of analysis largely depend on the quality of the preliminary preparation of the analyzed samples. During the sample preparation, the tasks of disinfecting pathogenic material, lysing cell membranes, removing compounds and impurities that inhibit the polymerase chain reaction (PCR), as well as concentrating nucleic acids are solved. The purpose of this work is to select modern approaches to sample preparation for the PCR. Among the variety of different methods of sample preparation, the most widespread are the methods based on chemical lysis of cell membranes using chaotropic compounds, followed by purification of nucleic acids by solid-phase extraction using magnetic particles. This approach is implemented both in commercial kits for manual sample preparation and in various automated systems for the isolation of nucleic acids. The analysis of commercially available stations for the isolation of nucleic acids shows that their technical characteristics are similar: the duration of one isolation cycle is 40–90 minutes; the volume of the analyzed samples is from 0.1 to 2.0 ml; the number of simultaneously processed samples max – 96, min – 8. The method of the nucleic acid isolation is the magnetic particles. The main differences are in the type of analyzed samples, and technologies for lysis of the test material and DNA extraction. Our experience in the use of magnetic particle kits for the isolation of nucleic acids, both in stationary and in field laboratories confirms the effectiveness and reliability of this technology. Further development and improvement of the hardware for such work will, obviously, be aimed at miniaturizing the equipment, developing field portable automatic nucleic acid extraction stations, as well as integrating the process of sample preparation and analysis by PCR in one device.

The article presents the meaningful review of the half-century history of the scientific activity development at the Moscow State Technical University of Civil Aviation, from the date of the University establishment in 1971 up to the present. It is noted that originally the university was faced with the challenge of designing an organizational structure comprising research units, which was successfully solved, and consequently, two years later the first research findings emerged. The competent strategy of the University Authority and the Academic Senate focused on the main fields of scientific research for decades. Obtaining employment by the acclaimed Russian scientists at the University as well as involvement of gifted and promising post-graduate researchers with science facilitated the formation of the University scientific schools. The article features the most significant stages of the scientific school formation of I.S. Golubev, I.M. Sindeev, A.A. Kuznetsov, V.I. Vasiliev, V.G. Vorobyov, S.V. Kuznetsov, N.N. Smirnov, Yu.M. Chinyuchin, V.G. Tsipenko, I.V. Nikitin, V.S. Strelyaev, V.S. Shapkin, S.K. Kamzolov, A.I. Kozlov, A.I. Logvin, V.D. Rubtsov, V.V. Solomentsev, E.E. Nechaev, O.V. Repinoy, O.D. Garanina, B.P. Eliseev, V.V. Vorobyov, etc. It is noted that the international scientific cooperation; the Thesis Board activity; publications, authors’ certificates, patents, University researchers’ awards in respective fields of science, demonstrating the results of fundamental and applied research, contributed to the formation of the University scientific authority. The article deals with the key issues of the University science development during different years as well as the current day challenges. It is shown that these days the University has the considerable scientific potential, which is capable of both identifying industry-specific scientific problems and solving them.

When using remote radiophysical methods in problems of monitoring the environment, the central place belongs to solving problems of determining its electrophysical characteristics, i.e. dielectric permittivity e, conductivity c (complex permittivity ek). The complex dielectric permittivity e, determined in one way or another, serves as the basis for determining the physical characteristics of the medium under study: temperature, humidity, salinity, hardness, etc. The method for remote determination of complex dielectric permittivity is proposed based on relative amplitude-phase relations in the radar receiver channels (orthogonal in polarization) (we call it determination of the polarization phasor). Knowledge of the polarization phasor makes it possible to determine uniquely both the permittivity and the conductivity of the surface under investigation. The latter is presented in the form of a series of universal graphs which allow one to directly interpret the physical characteristics of surfaces. It shows how the polarization phasor is placed on the KLL-sphere. In addition, the trajectory of the phaser on this sphere is investigated in the case when the physical characteristics of the investigated surface change. The random nature of local changes in the electrophysical properties of the surface under study leads to random fluctuations of the polarization phasor. The paper contains a two-dimensional density distribution of the permittivity and conductivity, as well as the corresponding one-dimensional densities. A graphic illustration of the relations obtained is given.

Monitoring technologies are rapidly developing at present and allow to extract and use non-coordinate information about objects. Noncoordinate information is the information about the type and properties of an object under study. Remote sensing is the main method of solving monitoring problems where special positioning belongs to the radar methods, based on space-time processing of signals and, in particular, on methods of radio polarimetry. It is necessary to have information about the surface in order to solve the monitoring task. The slightest changes in the electrical and physical properties of such areas as salinity, humidity, soil composition, etc. will lead to a change in the basic electrodynamics of the surface, notably its complex dielectric permittivity. The article demonstrates the precise solutions to the problems of radio-waves reflection from a layered surface with various laws of changes of the complex permittivity  in depth. Media with exponential and quadratic laws of variation  for arbitrary angles of incidence of the radio wave on the surface are considered. Precise decision is obtained for layered media with the law of change in the complex permittivity the polynomial and linear characteristics. A similar problem for the parabolic layer is considered separately. The detailed analysis of radio waves reflection from the medium with a matching layer is carried out. The nature of the electromagnetic field inside the transition layer is studied in detail. The article is illustrated by the graphs showing the dependences of an electromagnetic wave reflection coefficient on the layered medium with linear and exponential laws of variation of the complex dielectric constant over depth.

The reflected field calculation from the object can be described with the set of point reflectors with the coordinates in electromagnetic wave plane of incidence corresponding to two-dimensional grid nodes with rather small-sized step. At the same time, the single scattering model which does not consider the re-reflection and point elements cross impact is used in the reflected field calculations. The rapid direct and inverse transformation algorithm is used. The numerical solution algorithms of the direct and inverse scattering problems on the object are offered. The method uses the ray representations scattering fields which are based on the Huygens-Fresnel principle. The graphic diagram of the reciprocal object positioning and the observation plane from the reflected electromagnetic field object is represented. The double reflecting Gaussian surface is graphically figured. The figures of the module and the complex amplitude electric field strength of the reflected wave from a double Gaussian surface argument are provided. To shape the surface of the unknown object the recovery shape algorithm is used, by means of reflected wave phase. This algorithm is based on finding the complex matrix elements in dependence on absolute phase, which is proportional to the appropriate point object distance.

The paper considers the problem of finding the power flux density of signals reflected from two objects with different symmetric scattering matrices when they are irradiated with a completely polarized wave. The authors consider the case when the eigenvalues of the matrix are different given the form of the unitary diagonalization of the matrix for this case. The relation defining the diagonal elements of the factor is given. A comparison is made between the power flux density of the signals reflected from two objects with different scattering matrices when they are irradiated with a completely polarized wave. The power flux density of the electromagnetic wave reflected by this object is determined mathematically. Based on the definition of the scattering matrix, a transition to incident waves is performed. A parameter characterizing the degree of polarization anisotropy of the fluctuating object is given. The ratio for radar contrast is given. It is concluded that if the vector of the incident electromagnetic wave differs only in the scalar multiplier from the eigenvector of the matrix, the radar contrast will reach its maximum value. When the vector of the incident wave is proportional to the eigenvector, the value of the radar contrast reaches its minimum value. A problem is considered when the scattering matrices of two objects are simultaneously reduced to a diagonal form by means of a congruence transformation. Conditions are determined under which the Graves matrix of two scattering objects is reduced to diagonal form by means of a congruent transformation. A necessary and sufficient condition for the existence of a polarization basis is obtained in which the scattering matrices of two objects will simultaneously have a diagonal form.

Air temperature is one of the most important parameter of the atmosphere. The air temperature, especially in the lower atmosphere can have a significant effect on the aerodynamic characteristics of aircraft and is one of the main elements for the preparation of aviation weather forecasts. Methods of air temperature measuring in the atmosphere can be divided into two groups. The first group which combines the methods of contact measurement assumes the direct contact of the meter with the environment. The second group of methods, is now rapidly developing, combines the methods of remote measurement of the temperature. The problem of remote measurement of air temperature in the lower atmosphere is an important task, since the contact measurements, though highly accurate and informative, are held through certain and large enough time intervals (up to two times per day). To solve the problem of remote measurement of air temperature many different theoretical solutions and technical devices developed on their basis are proposed. All the proposed methods and techniques have limitations on their use imposed primarily by the precision with which you can define certain characteristics of the studied objects. The article considers a method that opens up the possibility of solving the problem of remote measurement of temperature in non-uniformly heated environment without losses of atmosphere type. It is based on radio emission own reception, intensity of which depends on its temperature. The proposed method of air temperature remote measurement is based on the well-known formula of S. T. Egorov and Y. M. Shestopalov. The article gives reasons for the possibility of using elliptical antennas for air temperature remote measurement in the lower layers of atmosphere.

A problem of electromagnetic wave backscattering on a chosen 3D object is solved. A differential equation which is linked change of polarization coefficient of reflected wave with variation of matrix elements of object scattering is obtained. Obtained relation enables to develop algorithms of fast numerical solution of inverse problem of scattering on this object that is determination of complex function of object surface scattering and restoration of unknown object shape on phase distribution of reflected wave. The method uses ray representation of scattering fields based on principle Huygens-Fresnel. The algorithm of object shape restoration on phase of reflected wave allows to restore not only smooth surfaces, but also object surfaces with smaller roughness than a wave length.

The real work is devoted to analytical definition of average values of polarizing invariants of compound radar objects at on-off dispersion on the basis of one-position measurements. Analytical results are confirmed with data of pilot studies. In work the problem of analytical definition of average values of polarizing invariants at dispersion of the electro-magnetic waves compound radar objects including both an extended (diffraction) element, and casual set of the simple (dot) centers of secondary dispersion for a case of an on-off radar-location by results of one-position measurements is considered. The data of pilot studies confirming analytical results are provided. At the same time full expression for the third parameter of Stokes of the field disseminated by a compound object shows the fact that Stokes's parameters of the wave disseminated by a compound object can't be determined by the sum of parameters of Stokes of the waves disseminated by each of object elements, but substantially are defined by communications between conditions of polarization of lenses. This fact completely accords with the principle of an emerdzhentnost which claims that integrated properties of system can't be defined only by the sum of properties of her elements, but are defined also by communications between system elements.

Analysis of compound radar objects polarization-energetical invariants determination was done in the first time for the bistatic scattering on the base of Kell theorem generalization.

The article is devoted to introduction the main notions which allows us to create a theoretical foundation of man-made small-scale object “polarization track” against random surface. The existing of this effect was established using the experimental results. In the article the problems of small-scale man-made radar object polarization “track ” on the surface are investigated An analysis both statistical effects and measured values was made with the use of emergence principle and polarization proximity (distance) notions.

The characteristics of object scattering matrix are analyzed. The system of differential equations is obtained. It correlates (links) changes in ratio magnitude of Grave’s own matrix values with the corresponding changes in matrix elements the magnitude scattering.

This article (part 1) is devoted to simplified explanation of Robert Kell equivalence theorem about the derivation of bistatic RCS based on the monostatic measurements. In contrast to R.Kell’s original study, using definition based on Statton - Chu integral, this article uses methods of physical optics. The analysis was made for a complex radar object, including a considerable number of centers of scattering, also for a complex radar object, including an extended scatterer. This article (part 2) is devoted to experimental results based on Robert Kell equivalence theorem about the derivation of bistatic RCS in accordance with monostatic measurements.

The article offers a method to determine the dielectric penetrability of surfaces in optic diapason. To do that it is necessary to take pictures of the studied surface with digital camera at day light, using orthogonal polirization filters then to treat the pictures obtained as prescribed.

The satellite INTERBALL-2 has an orbit with high inclination (62.8°), covering the altitude range between a few hundred and about 20000 km. The ambient plasma conditions along this orbit are highly variable, and the interactions of this plasma with the spacecraft body as well as the photo-electron sheath around it are considered to be interesting topics for detailed studies. The electric potential of the spacecraft with respect to the ambient plasma that develops as a result of the current equilibrium reacts sensitively to variations of the boundary conditions. The measurement and eventual control of this potential is a prerequisite for accurate measurements of the thermal plasma. We describe the purpose and technical implementation of an ion emitter instrument on-board INTERBALL-2 utilising ion beams at energies of several thousand electron volts in order to reduce and stabilise the positive spacecraft potential. First results of the active ion beam experiments, and other measures taken on INTERBALL-2 to reduce charging are presented. Furthermore, the approach and initial steps of modelling efforts of the sheath in the vicinity of the INTERBALL-2 spacecraft are described together with some estimates on the resulting spacecraft potential, and effects on thermal ion measurements. It is concluded that even moderate spacecraft potentials as are commonly observed on-board INTERBALL-2 can significantly distort the measurements of ion distribution functions, especially in the presence of strongly anisotropic distributions.Key words. Space plasma physics (active perturbation experiments; spacecraft sheaths · wakes · charging; instruments and techniques).