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The article substantiates the feasibility of developing minimally invasive operations on the adnexa and minimizing surgical trauma. The technique of the modified laparoscopic surgery method proposed by the authors for benign diseases of the adnexa is described in details. The results of treatment of 37 patients operated on by the presented method are considered. The selection criteria for patients for the application of this method of surgical treatment are determined. It is shown that the presented method corresponds to the current trend of minimizing surgical trauma, has a good cosmetic effect, helps to reduce postoperative pain, and is also economically feasible, because it does not require the use of additional endoscopic instruments.

This publication examines the existing risks of obstetric complications and other reproductive disorders in women with gynecological diseases. The paper also discusses the issues of the pre-school training of women with gynecological diseases, with special emphasis on the use of dipyridamole, due to its pleiotropic action.

This publication is devoted to one of the most relevant areas of gynecological practice - the use of combined oral contraceptives (COCs), taking into account their positive non-contraceptive properties. The issue of how to use COCs with the benefit of reproductive health of women, with what to combine them and how to prevent the risks associated with taking hormonal drugs, is reflected in detail. The information is presented in the form of an analytical review of international studies on the benefits and risks of using COCs.

The influence of controlled rolling and the parameters of subsequent technological heating on the processes of structure formation in high-strength sheet steels EH36 and X70 is investigated. It has been established that when redistributing a thick sheet into products, it is necessary to minimize the temperature-time parameters to prevent softening processes. Welding, as one of the sources of technological heating, leads to a change in the structure in the zone of thermal influence and uneven distribution of hardness over the cross section of welded joints, which reduces the uniform strength of the structure as a whole. Short-term heating (about 15 minutes) even to temperatures above Ac1 (760 ° C) and cooling in air in the weld zone do not lead to significant changes in structure and hardness, but the degree of uniformity of the welded sheets increases.

The need for post-abortion rehabilitation is conditioned by the frequency and relevance of delayed and long-term complications of induced abortions. Numerous studies demonstrate feasibility of using oral contraceptives for the prevention of adverse effects of abortion not only due to their good contraceptive effect, but also their ability to adequately rehabilitate the function of the hypothalamic-pituitary axis by adjusting hormone profile and levelling hormonal fluctuations, as well as their therapeutic effects, especially those produced by three-phase combined oral contraceptives.

Miscarriage is contributed by a number of different factors; among those, magnesium deficiency has a specific mechanism and polypathogenic effects. According to the results of numerous studies, magnesium medicines are effective in complex therapy of miscarriage as they affect key pathogenetic links. Prevention of miscarriage should be based on careful identification and elimination of the causes of miscarriage, examination and rehabilitation of nonpregnant women.

The article refers to the psychological aspect of interference. Perception of the text for translation is based on a number of attributes that are compared by a communicant with available in his memory standards: lexical, grammatical, stylistic and others, acquired during training and practice.

The paper discusses ways to increase the efficiency of using propane-butane compositions on board a car. The main reasons for the decrease in power during the transition from gasoline to propane-butane are given and the ways to solve them by changing the conditions of supply to the engine intake, as well as the use of thermochemical recovery of exhaust heat, are analyzed.

We discuss the results of studies of natural and artificial small-scale turbulence in the upper ionosphere. The first data on the spectrum of sizes of irregularities at altitudes 240–340 km were obtained in the 1970s by the method of aspect scattering of radio waves and the method of radio-raying of the ionosphere by radio signals from Earth-orbiting satellites. New data on the irregularities with a size of about 20 m were obtained by the method of backscattering of radio waves in the period 2009–2011 using the “Sura” facility radar. The radar measurements allow one to complement the empirical model of irregularities in the F layer of the ionosphere.

Hydrogen transport by 100-μm-thick vanadium and palladium membranes was studied in the pressure range from 1 × 10−8 to 4.5 × 10−1 MPa at a temperature of 400°C. Both sides of the vanadium membrane were covered by 2 μm of palladium (Pd-V-Pd) for facilitating the dissociative absorption and associative desorption of H2 molecules. At low pressures, hydrogen flux densities through vanadium and palladium membranes are nearly the same; at high pressures, the flux through the vanadium membrane becomes 16 times larger than the flux through the palladium membrane and attains a value of 2.4 scc cm−2 s−1. This flux of permeating hydrogen is larger than all values ever observed earlier for membranes made of group 5 metals or any other unsupported metal membranes.

The signals of radio-wave backscattering from small-scale irregularities located at the altitudes from 200 to 400 km were first recorded by the “Sura” facility radar in 2006. The experiments with the “Sura” facility were repeated in the summer of 2009. Radar signals scattered in the altitude range 300–500 km were observed in 10% of the cases. Pronounced variation in the radar-signal intensity was observed during modification of the ionosphere by high-power radio waves. We discuss the possibility of an experimental study of the spectrum of small-scale turbulence in the upper ionosphere by the modified method of backscattering of HF waves.

The thermal stability of palladium-covered niobium, a composite used in hydrogen-tight membranes, is studied. Palladium is applied by the method of plasma sputtering. The thermal degradation of the coating is judged from a decrease in its ability to prevent niobium oxidation. It is found that the degree of oxidation of the samples heated in air at 693 K drops when the thickness of the coating increases in the range 2.5–1000.0 nm. The reason is heating-induced destructive modifications of the coating morphology, which are observed under a scanning electron microscope. The thicker the coating, the higher the temperature of onset of destruction. At temperatures above 873 K, the initially smooth continuous coating becomes highly porous and this porous layer does not change upon subsequent heating (up to 1273 K). Critical factors and possible mechanisms of thermal degradation of palladium coatings on hydrogen-tight composite membranes are discussed.

We present the results of the experiment on studying the multifractal structure (with inhomogeneity sizes from tens to hundreds of meters across the Earth’s magnetic field) of the artificial ionospheric turbulence when the midlatitude ionosphere is affected by high-power HF radio waves. The experimental studies were performed on the basis of the “Sura” heating facility with the help of radio sounding of the disturbed region of the ionospheric plasma by signals from the Earth’s orbital satellites. The influence of the magnetic zenith effect on measured multifractal characteristics of the small-scale artificial turbulence of the midlatitude ionosphere was examined. In the case of vertical radio sounding of the disturbed ionosphere region, the measured multipower and generalized multifractal spectra of turbulence coincide well with similar multifractal characteristics of the ionospheric turbulence under natural conditions. This result is explained by the fact that the scattering of signals by weak quasi-isotropic small-scale inhomogeneities of the electron number density in a thick layer with a typical size of several hundred kilometers above the region of reflection of high-power HF radio waves gives the major contribution to the observed amplitude fluctuations of received signals. In the case of oblique sounding of the disturbance region at small angles between the line of sight to the satellite and the direction of the Earth’s magnetic field, the nonuniform structure of the small-scale turbulence with a relatively narrow multipower spectrum and small variations in the generalized multifractal spectrum of the electron number density was detected. Such a fairly well ordered structure of the turbulence is explained by the influence of the magnetic zenith effect on the generation of anisotropic small-scale artificial turbulence in a thin layer having a typical size of several ten kilometers and located below the pump-wave reflection height in the upper ionosphere.

Using the method of radio sounding of the mid-latitude ionosphere by the satellite signals, we study the multifractal structure of small-scale ionospheric turbulence during a solar eclipse. The measured multipower and generalized multifractal spectra of small-scale ionospheric turbulence at the initial and closing stages of the eclipse turn out to be almost identical on the space radio paths with different orientations. This is indicative of a sufficiently high stability of the nonuniform spatio-temporal distribution of small-scale fluctuations of the ionospheric electron number density under conditions of geophysical disturbances due to global physical processes in the ionospheric plasma during a solar eclipse.

We consider the problem of diagnostics of the local structure of small-scale ionospheric turbulence using the multifractal analysis of received signals from the Earth’s orbital satellites after the radio sounding of the inhomogeneous ionosphere by these signals. In particular, it is shown that analysis of the multifractal structure of the received-signal amplitude records by the method of multidimensional structural functions allows one to determine the indices of the multipower local spectra of the small-scale ionospheric turbulence, which are inherent in it due to the nonuniform spatial distribution of small-scale fluctuations of the electron number density. It is noted that information on the multipower spectrum of small-scale ionospheric turbulence is not available for the conventional radio scintillation method based on the classical spectral analysis of received signals during the remote radio sounding of the ionosphere. At the same time, the method of multidimensional structural functions is efficient under conditions of actual nonstationarity of the process of scattering of the HF radio waves by the randomly inhomogeneous ionospheric plasma. The method of multidimensional structural functions is used for the multifractal processing of received signals of orbital satellites during special experiments on radio sounding of the midlatitude ionosphere under natural conditions and its modification by high-power HF radio waves. First data on the indices of the multipower local spectra of small-scale ionospheric turbulence are obtained.

We show the results of the first experimental studies of the multifractal structure of the developed artificial ionospheric turbulence. As a result of the special multifractal analysis of the recorded amplitudes of signals from the orbital satellites, which were obtained during the experiments on radio tomography of the irregularities excited in the ionosphere by the powerful mid-latitude heating facility “Sura,” it is found that the characteristic multifractal structure of these records is caused by the nonuniform spatial distribution of the small-scale fluctuations of the electron number density in the artificial irregularities of the ionospheric plasma. Comparative analysis is performed for the multifractal spectra of fluctuations of both the amplitudes and energies of signals received from the orbital satellites upon radio transmission probing of the region of artificial ionospheric turbulence by these signals at three observation points located near the “Sura” heating facility and spaced apart to a distance of about 100–150 km.

We consider the problem of obtaining reliable values of the local-spectrum indices of the electron number density fluctuations for small-scale ionospheric turbulence. It is shown that the use of a multifractal analysis in combination with the synchronous correlation processing of the received signals in the experiments on remote radio sounding of the ionosphere by satellite signals permits one to solve the posed problem. In this case, the true values of the local-spectrum indices of small-scale ionospheric turbulence, which are measured in such specialized experiments under natural conditions and during modification of the ionosphere by high-power HF radio emission, can differ notably from their standard values obtained within the framework of the classical method of radio scintillations, in which only correlation processing of the data is used.

We present the results of studying the multifractal structure of intermittency in a developed ionospheric turbulence during special experiments on radio-raying of the midlatitude ionosphere by signals from orbital satellites in 2005–2006. It is shown, in particular, that the determination of multidimensional structural functions of the energy fluctuations of received signals permits one to obtain the necessary information on multifractal spectra of the studied process of radio-wave scattering in the ionosphere. Experimental data on multifractal spectra of slow fluctuations in the received-signal energy under conditions of a developed small-scale turbulence are compared with the existing concept of the radio-wave scattering within the framework of the statistical theory of radio-wave propagation in the ionosphere. It is inferred that under conditions of a developed ionospheric turbulence, the multifractal structure of the intermittency of slow fluctuations in the received-signal energy is a consequence of the intermittency of small-scale fluctuations in the electron number density of the ionospheric plasma on relatively large spatial scales of about several ten kilometers.

We present the results of studies of the multifractal structure of slow (of duration τ ≈ 10 s) fluctuations of the received-signal amplitudes in special experiments on radio-raying of the midlatitude ionosphere by signals from orbital satellites in 2004–2006. It is shown, in particular, that the method of multifractal analysis of amplitude records of the received signals yields information on the spectrum of large-scale ionospheric inhomogeneities, which is inaccessible for the classical method of radio scintillations. From the results of measurements with the use of multifractal processing of experimental data, we found that large-scale (tens of kilometers) quasiregular electron-density inhomogeneities of traveling ionospheric disturbances (TIDs) have a power-law spectrum. It is exactly the power-law form of the spatial spectrum of large-scale inhomogeneities of TIDs that can be the reason for the observed multifractal structure of the intermittency of slow fluctuations of the received-signal amplitudes. However, under conditions of a developed small-scale turbulence of TIDs, the observed multifractal structure of the received signals is, as a rule, stipulated by the spatial inhomogeneity of the variance of the integral electron-density fluctuations of small-scale inhomogeneities on scales comparable with the sizes of large-scale inhomogeneities of TIDs.

We consider the problem of relating the local structure of small-scale ionospheric turbulence to the measured frequency-spectrum indices and fractal dimensions of amplitude records of the signals received on the Earth during remote sensing of the ionosphere onboard the satellites. It is shown that knowledge of these parameters permits one to determine the true values of the local-spectrum indices of the electron-density fluctuations for isotropic small-scale turbulence of the ionosphere both under natural conditions and during its modification by high-power short-wave radiation as well as to specify fractal dimensions of space filled by small-scale irregularities of the turbulent structures in the ionosphere. We show the necessity of detailed experimental studies of the fractal properties of small-scale ionospheric irregularities of both natural and artificial origin by using a multifractal analysis in combination with the synchronous correlation processing of received signals during remote sensing of the ionosphere. This will give important information on the local structure of small-scale ionospheric turbulence inaccessible for studies within the framework of the classical method of radio scintillation.

The remote results of immunity investigation in 30 patients after organ-preserving surgery and in 30 patients after splenectomy forspleen rupture are presented in the article. Indexes of cellular and humoral immunity were normal and life quality did not differ from that in healthy individuals after organ-preserving operations with splenic artery ligation. Splenectomy leads to deterioration of life quality and disorders in cellular immunity including decrease of T-helpers/inductors cells (CD4), immunoregulatory index (CD3/CD4) and general number of T-lymphocytes (CD3) in some cases on background of compensatory increase of normal killers (CD16). It was observed significant decrease of IgG and IgM levels. Values of IgA and cytokines IL-1, IL-2, IL-6 and TNF remained normal. Level of immunosuppression is reduced due to development of splenosis.В статье представлены результаты исследований иммунитета в отдаленном послеоперационном периоде у 30 пациентов после органосохраняющих операций на поврежденной селезенке и у 30 больных после спленэктомии при закрытой травме живота. После органосохраняющих операций с лигированием селезеночной артерии показатели клеточного и гуморального иммунитета были в норме, качество жизни достоверно не отличалось от такового у здоровых лиц. После спленэктомии качество жизни хуже, отмечаются нарушения в показателях клеточного звена иммунитета, заключающиеся в достоверном уменьшении количества Т-хелперов/индукторов (CD4), иммунорегуляторного индекса (CD3/CD4) и в ряде наблюдений общего количества Т-лимфоцитов (CD3) на фоне компенсаторного увеличения уровня нормальных киллеров (CD16). Констатировано достоверное снижение уровня IgG и IgM. Уровень IgA и цитокинов ИЛ-1, ИЛ-2, ИЛ-6, ФНО остается в пределах физиологической нормы. Выраженность иммуносупрессии уменьшается при развитии спленоза.

We report on the results of the first special experiment on radio sounding of the midlatitude ionosphere by signals from in-orbit satellites at a frequency of 150 MHz under quiet geophysical conditions. Along with the conventional correlation processing, fractal processing of the received signals was also performed. Using the fractal approach, we obtained first data on the sources and generation mechanisms of small-scale plasma inhomogeneities of the traveling ionospheric disturbances (TIDs) in the upper ionosphere. It is noted that the phenomenon of nonlinear “ breaking” of the acoustic-gravity waves entering the ionosphere from the underlying atmosphere plays the crucial role in the formation of plasma inhomogeneities of the TIDs.

We consider the problem of phase fluctuations of radio waves behind a turbulent optically thin irregular layer (phase screen). Expressions are derived for the main statistical characteristics of phase fluctuations in the case where modern direct methods based on measurements of the complex field of the received radiation are used to obtain these characteristics. Regimes of weak and saturated scintillations of signals are analyzed. It is shown that in the case of weak scintillations, such statistical characteristics of phase fluctuations of the received radiation as the structure function and the fluctuation spectra for single-point and interference reception almost coincide with those at the screen output. In the regime of saturated scintillations, we obtain an information on the structure function of phase fluctuations of the received radiation in the cases of relatively large and small spatial separations of the reception points. The results obtained allow one to correctly analyze the data of modern experiments on remote sensing of the near-Earth and space plasmas with the help of direct phase methods for environmental diagnostics.

We consider the problem of phase fluctuations of radio waves behind a strong phase screen and in an optically thick layer. It is shown that the phase-fluctuation distribution of the received radiation at an observation point located in the saturated-scintillation area behind a turbulent phase screen is almost identical to the normal distribution of phase fluctuations of the wave on the screen. Amplitude and phase fluctuations of the received radiation are uncorrelated both for single-point and space-diversity reception if, in the latter case, the distance between the observation points exceeds the spatial scale of the diffraction component of the complex field of the received signal. Expressions for the mean square and the structural function of phase fluctuations of radio waves behind a turbulent phase screen in the saturated-scintillation regime are obtained. It is shown that the structural function of phase fluctuations in the diffraction component of the scattered field, which is exactly the function that forms saturated scintillations of the received radiation, almost coincides with the structural function of phase fluctuations on the screen. It is also shown that the diffraction effects can be neglected and the geometric-optical approximation should be used when calculating statistical characteristics of phase fluctuations of a plane wave in the saturated-scintillation area in an optically thick layer with large-scale refractive-index irregularities.

We study theoretically the profile of a spectral line of radiation which is received by an interferometer after propagation through a medium with developed turbulent structure. We derive a formula describing the resulting frequency spectrum of an initially monochromatic radiation after its propagation through a multi-scale medium with “strong” large-scale and “weak” small-scale irregularities. It is shown that the frequency spectrum observed in this case should comprise the main spectral line with Gaussian profile and “wings” decreasing according to a power law with index dependent on the orientation of the interferometer baseline with respect to the direction of regular drift of “frozen-in” irregularities of the medium. We analyze distortions of the spectral response of a very-long-baseline interferometer due to the effect of large-scale irregularities of a medium with developed turbulent structure on wideband radiation from extraterrestrial discrete radio sources. It is shown that if the amplitude fluctuations of the received radiation are weak, then the measured frequency spectrum contains information on the drift velocity and the index of the spatial spectrum of interplanetary plasma irregularities with scales from hundreds to thousands of kilometers.

We present the results of the last experiments aimed at studying the phenomenon of mid-latitude F-spread by radio-raying of the ionosphere using the signal from the SURA facility received onboard the NASA spacecraft WIND. A generalized model of spatio-temporal distribution of the electron density in the mid-latitude ionosphere under F-spread conditions is proposed. Based on this model describing large-scale ionospheric irregularities, we calculate the ray trajectories of HF radio waves. We also discuss the known results of comparative measurements of the variances of relative electron-density fluctuations in large-scale irregularities of the mid-latitude ionosphere, carried out by the OGO-6 spacecraft, and the frequency broadening of the ionograms of ground-based stations for the vertical sounding. It is shown that the proposed model of electron-density disturbances in the mid-latitude ionosphere in the presence of F-spread is able not only to describe well the main qualitative feature of HF radiowave propagation under disturbed geophysical conditions, but also to reproduce quite accurately the quantitative parameters of the frequency broadening of reflected HF signals under conditions of standard and developed F-spread.

The authors have experience in organ-preserving operations for spleen rupture with the splenic artery ligation in 156 casualties. They consider that such operations let to preserve the spleen, to avoid the postoperative rebleeding and ischemia of pancreas tail and body. Also it is accompanied by the low indications of lethality and postoperative complications. The authors consider that this operation is alternative to splenectomy and other techniques of organ-preserving operations in case of spleen trauma.

Results of the 1999 experiments on receiving radio-frequency signals from the SURA and EISCAT facilities on the WIND spacecraft at 5475 kHz are presented. Power and frequency distortions imposed by near-Earth plasmas on the response of SURA-EISCAT, an active decameter radio interferometer with a superlong baseline of ∼2000 km, are studied. Quasi-oscillatory variations in the intensity of the received radiation with a period of several tenths of a second and the corresponding maximum in the intensity fluctuation spectrum are observed during synchronized operation of the facilities under both quiet and perturbed geophysical conditions including the occurrence of mid-latitude F spread. Variations in the mean frequency of the spectral line both because of the motion of the spacecraft and the large-scale traveling ionospheric disturbances are detected. The obtained results are compared with the modern theoretical concept of propagation of short radio waves in a randomly irregular ionospheric plasma. The possibility to realize the limiting angular resolution of a ground-based decameter interferometer with a superlong baseline for observations of discrete space radio sources is discussed.

We consider some theoretical issues concerning diffraction of radio waves in a randomly irregular ionosphere with application to the problems of long-wavelength interferometry of cosmic objects. The statistical characteristics of intensity fluctuations of the decameter radio emission from discrete sources in the case of ground-based observations by two-element interferometers with very long and small baselines are analyzed. Analytical expressions are obtained for the autocorrelation function of the radiation intensity and for the scintillation spectrum of a point source in the limiting cases of large and small phase increments in an irregular ionospheric plasma. We find that in the case of radio interferometric reception, the scintillation spectrum corresponding to observations of a source by a single antenna is transferred from the zero-frequency region to the region of the Doppler frequency of the interferometer. It is shown that decameter ground-based and space-borne radio interferometers can be used to study the angular distribution of the radio brightness of cosmic sources under conditions of both quiet and disturbed ionosphere.

We consider some effects of the VHF radio wave propagation in randomly irregular plasma near the Earth. Applications of these effects to main problems of decameter radio astronomy are discussed. In particular, we show that significant measurement errors of about tens to hundreds of percent for the intensity of the VHF radio emission from an extra-terrestrial source may occur due to scattering and focusing/defocusing of the radiation in the ionosphere if VHF radio astronomical facilities operate at middle latitudes. We find that the angular resolution of discrete radio sources observed using radio interferometry and the well-known scintillation methods cannot be better than about a degree due to the effect of the developed ionospheric turbulence. We propose a modified scintillation method based on the spectral analysis of radio emission from discrete sources, which allows the useful high-frequency signal corresponding to diffraction of VHF emission at weak inhomogeneities of interplanetary plasma to be separated against strong, relatively low-frequency fluctuations of the received radiation due to the effect of the developed turbulent structure of the ionosphere. We show that such a method allows the angular resolution of extra-terrestrial radio sources to be improved up to arcsecond level.

We present the results of the first space-borne SURA-WIND experiment aimed at studying the features of short-radiowave propagation in the case of radio occultation of the near-Earth plasma in the presence of a developed midlatitude F-spread. We discover the effect of screening of a signal at frequency 4525 kHz that is 0.8 MHz higher than the minimum observed frequency for the SURA-WIND radio path determined using the ionograms obtained by the ground-based vertical-sounding station. The screening effect is explained by the effect of large-scale irregularities of the number density of ionospheric electrons of sizes about a few tens of kilometers, which lead to the appearance of electron-density depletion regions in the ionosphere stretched along the geomagnetic field. These depletion regions are separated by the ordinary plane-parallel distribution of the electron number density. The features of the frequency spectra of intensity fluctuations of the HF radiation over the SURA-WIND radio path in the presence of a developed midlatitude F-spread are considered.

We present experimental results on reception of VHF signals of the transmitting facility “Sura” of the Radiophysical Research Institute by the NASA spacecraft WIND. The experiments were performed during daytime during the summer seasons 1997–1998. The dependence of power and spectral characteristics of the VHF radio waves on the power of the sounding radiation is analyzed. We find that, in a wide range of effective powers of the VHF radiation from about 40 kW to 160 MW, the phenomena observed in the radiation received onboard WIND (such as focusing, scintillations, or frequency deviations of signals) does not usually depend on the operation mode of the “Sura” facility. At the same time, broadening of the radiation pattern of the facility and decrease of the mean level of the received signal by about 6 dB toward the direction of maximum of the radiation pattern were observed at the peak radiation power of the facility. The experimental results are compared to present concepts on effects of self-focusing instability and nonlinear defocusing of VHF radio waves in the ionospheric plasma.

The modernization of the proton spin decoupling unit in the NMR spectrometer is described. It consists in designing a pulsed modulator and including it in the circuit of the spin decoupling unit. The modified unit ensures a thermal stability of the sample at a level of ±2°C and an ±10% accuracy in measuring factors of the nuclear Overhauser effect for 13C nuclei. The unit was tested by measuring the factors of the nuclear Overhauser effect for 13C nuclei in a solution of deuterated acetone (10%) in ethylbenzene (90%).

Using the method of parabolic equation (MPE), we obtain transfer equations for the mean field, the space-coherence function, and the ray intensity of a radiowave beam as it is reflected from a plasma layer with random inhomogeneities. The general solutions of these equations are found. Special attention is given to the case of radiowave beam reflection from a linear plasma layer with large-scale electron-density inhomogeneities. If a weakly directed transceiving SW antenna is used, the shortwave scattering can lead to a pronounced (of the order of 3 dB) decrease in the intensity of a vertical-sounding signal reflected from the ionospheric F2 layer only under the conditions of abnormally strong ionospheric electron-density perturbations.

A model of decameter-decimeter radio wave propagation in a strongly inhomogeneous mid-latitude ionosphere is constructed using a modified method of radio wave refractive scattering. The model establishes the relationship between the basic statistical radio wave characteristics and the turbulence parameters of the upper ionosphere. Different aspects of the theory of radio wave refractive scattering are considered in application to the study of amplitude and phase fluctuations of decameter-decimeter radio waves propagating in a three-dimensional randomly inhomogeneous ionosphere with an arbitrary electron density distribution.

Using the method of refractive scattering of radio waves (RSRW), we solve the problem of space correlation of scintillations of radiation from an extended source in a randomly inhomogeneous medium. General expressions are obtained for the index and radius of the space correlation of fluctuations of intensity of radiation from a source with finite angular dimensions as it propagates though a multilayered medium with refractive index fluctuations. The RSRW method is similar to the diffraction calculation of space correlation of scintillations of an extended source in a thick layer with inhomogeneities. We note that under certain conditions an increase in the number of inhomogeneous layers on the radio wave propagation path leads to a pronounced decrease in the scintillation index and an increase in the space correlation of fluctuations of intensity of received radiation from an extended source. The results obtained have a simple geometric-optical interpretation. We indicate a specific feature in determining the angular dimensions of extended radio sources using the known method of scintillations.

The problem of defining the spectral form of ionospheric irregularities with dimensions from hundreds to thousands of meters is considered. A generalized model is proposed for the ionospheric turbulence spectrum, taking into account both the anisotropic properties of the large-scale fraction of irregularities and the dependence of the anisotropy (elongation) of small-scale irregularities of the upper ionosphere along the Earth magnetic field direction on the transverse scale of those irregularities. Relations have been derived to determine the basic parameters of the irregularity spectrum of the uppers ionosphere (anisotropy indices for large-scale and small-scale fractions) and the depth of a thin ionospheric layer through measurement of the spectral characteristics of amplitude and phase fluctuations of orbital satellite signals. Using this model of the plasma irregularity spectrum, we can explain consistently many well-known experimental data on spectral characteristics of the phase and amplitude fluctuations of orbital satellite signals both in the high-latitude and midlatitude ionosphere.

The outcomes of 383 cases of heavy combined traumas (n=273) and isolated (n=110) closed injuries of the abdomen with spleen damage were analyzed. The overall mortality was 11.74% (n=45), whereas the mortality rate during the first day after admission was 7.83% (n=30). Removal of a spleen was executed at 228 patients. The spleen-preserving operation with ligation of splenic artery, was performed in 155 patients. The optimal level of the splenic artery ligation proved to be in its proximal and median parts. The postoperative CT-angiogarphy and Doppler US scanning together with the three-dimensional reconstruction confirmed that blood supply of the body and tail of the pancreas was satisfactory thanks to the natural collateral blood circulation. The dramatic decrease in lethality and of postoperative complication rates allows to consider spleen-preserving resections to be a good alternative to spleenectomy.