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Relevance. High values of berry quality traits increase the breeding and production worth of strawberry varieties and hybrids. Important characteristics of the quality of berry are the average fruit weight, the firmness of the pulp of berry, the height and the largest diameter of berry. It is possible to achieve a high level of values of these traits by combining the maximum similarity of their variation in one genotype. The aim of this work was the description of the associated variability of berry quality traits in a number of strawberry varieties and hybrid selections and the identification of the most promising from them according to the studied characteristics.Methods. The studies were carried out in 2019–2021, 12 varieties and 8 hybrid selections were studied for a number of economically significant traits of berry quality: average fruit weight, g; berry pulp firmness, g; height and largest diameter of the berry, mm; content of dry soluble solids in berries, Brix, %. Results. It has been established that the genotype makes the greatest contribution to the diversity of the studied samples. A relatively small factorial influence of the growing year on the overall variation of varieties and selections for the studied traits (from 0.06 to 1.6% of the phenotypic variance) indicates a high adaptability potential of the studied forms for growing in this natural and climatic zone, due to the specific properties of the genotypes of varieties and strawberry hybrids. By calculating pairwise Pearson's correlations in combination with the cluster analysis by the Ward's method as one of the procedures of multivariate mathematical statistics, an evaluation of the compatibility of variability by the studied traits was given, the varieties promising for breeding and cultivation under regional conditions in terms of berry quality have been identified — Florence, Vivaldi, Nelli, Syria, Belrubi, Honeoye and Kemia, as well as valuable for breeding hybrids — 10-1-15 Belrubi × Nelli, 35-14-15 Belrubi × Onda and 35-11-15 Belrubi × Florence.

Introduction . Greater omentum cysts found in children belong to a rare pathology occurring as frequent as 1:23000. During the majority of observations, they are diagnosed during an ultrasound examination and abdominal computed tomography. However, in some cases it is impossible to restore an organ from which a cyst can originate using visual non-invasive methods. Purpose . This paper presents a clinical case of surgical treatment of a 7-year-old child with giant pseudocyst of the greater omentum. Materials and methods . The patient complained of periodic pains in the abdomen and increased abdominal size. The diagnosis was made following an abdominal ultrasound examination when a giant liquid formation (200×180×220 mm) was found. Subsequent MRI and CT tests of the abdomen gave a view of a cystic formation which was allegedly a cystadenoma of the left ovary. A cystic formation occupying the entire abdominal cavity was detected during a laparoscopy. Puncture and aspiration of 2.7 L of serous and hemorrhagic liquid were performed. It was found out that the formation originated from the greater omentum. The greater omentum was resected within healthy tissues along the mesocolonic border and cystic membranes were removed via a separate incision. Conclusion . When diagnosing large cystic abdominal formations, a final diagnosis of organ origin can sometimes be established during laparoscopy only when endosurgical treatment could be done (in the presence of a respective technique and educated specialists).

The erosion behavior of W-Pd bimetallic systems has been investigated for both hydrogen-saturated (H/Pd ∼ 0.65) and unsaturated states during impact of a steady-state nitrogen plasma from a mirror Penning discharge. An essential decrease by factors of about 2-5 in the erosion rate of W was observed for hydrogen-saturated W-Pd samples in the nitrogen ion energy range from 0.8 to 1.6 keV. Possible reasons for this erosion behavior are discussed. Isotherms and isobars of hydrogen permeability through W-Pd systems were measured in the temperature range of 573-973 K and hydrogen pressure range of 1.33 x 10 2 to 10 5 Pa. It is shown that the limiting stage of permeation process is, most likely, the diffusion in the W film. The activation energy of hydrogen permeability was determined to be ∼12 kJ/mol, this being much lower than the literature data for bulk tungsten at molecular hydrogen-driven permeation. Possible mechanisms are suggested and analyzed to explain the observed decrease in he activation energy of hydrogen penetration through W-Pd systems.

The distribution of antenna-driven fields of electromagnetic waves in the local Alfven resonance (AR) region is studied under resonant conditions, when the axial period of the fundamental harmonics of magnetohydrodynamic oscillations in the axial direction is twice as large as the pitch length, and the poloidal number of the fundamental harmonics is twice as small as the polarity of the helical coils. It is shown that taking into account the helical inhomogeneity of the steady magnetic field can remove infinite discontinuity of the wave fields, which is present in the case of a straight confining magnetic field, rather than electron inertia or finite ion Larmor radius. Radio frequency power absorption within the local AR is compared with the case when AR structure is governed by electron inertia or finite ion Larmor radius. Another approach is proposed to explain the helicity induced gap in the Alfven continuum.

Distribution of antenna-driven electromagnetic wave fields within the local Alfvén resonance is studied under resonant conditions such that the axial period of the fundamental harmonic of the magnetohydrodynamic oscillations in the axial direction is twice as large as the pitch length, and the poloidal number of the fundamental harmonic is twice as small as the polarity of the helical coils. It is shown that taking account of the helical inhomogeneity of the steady magnetic field can remove the infinite discontinuity of the wave fields that takes place in a straight magnetic field rather than with electron inertia or a finite ion Larmor radius.

Dynamics of a hot electron cloud with an initially Maxwellian electron distribution is considered both numerically and analytically. It is shown that only a small group of the electrons propagates into the plasma but the main group of the electrons is concentrated near the initial location of the cloud. The distribution of the electrons left presents a plateau with the maximum velocity growing linearly with distance.

We report experimental results obtained by the emulsion chambers on board of the long duration balloon. We have been carrying out the trans-Siberian-continental balloon flight since 1995, and the results from 1995 to 1996 experiments are presented here. Total exposure of these two years amounts to 231.5 m 2 h at the average altitude of ∼32 km. The energy range covers 10–500 TeV for proton-primary, 3–70 TeV/n for helium-primary, and 1–5 TeV/n for Fe-group ( Z =26–28), though statistics of heavy components is not yet enough. Our preliminary data show that the spectra of the proton and the helium have nearly the same power indices ∼2.80, while those of heavier ones become gradually harder as the mass gets heavier, for instance the index is ∼2.70 for CNO-group and ∼2.55 for Fe-group. It is remarkable that a very high energy proton with multi-PeV is detected in 1995 experiment, and the estimated flux of this event coincides with a simple extrapolation from the energy spectrum with the power index 2.8 observed in the range 10–500 TeV. It indicates that there is no spectral break at around 100 TeV, in contrast to the maximum energy predicted by the current shock-wave acceleration model. This evidence requires some modification on the acceleration and/or propagation mechanism. Also we present all-particle spectrum and the average primary mass in the energy range 20–1000 TeV/particle. Our preliminary data show no drastic change in mass composition over the wide energy range, at least up to 1 PeV/particle, though the statistics is not yet enough to confirm it concretely. The flight performance and the procedure of the analysis, particularly the energy determination methods and the detection efficiency calculation are also given.

We report experimental results obtained by using a wide-gap type emulsion chamber flown in the first Japanese-Russo joint balloon project, called RUNJOB ( RU ssia- N ippon JO int B alloon-program). Two balloons were launched from Kamchatka in July 1995, and both were recovered successfully near the Volga River. The exposure time was 130 hours for the first flight and 168 hours for the second. The mean ceiling altitude, in both flights, was 32 km corresponding to 10 g/cm 2 . Total area of the emulsion chamber was 0.8 m 2 , and the thickness 0.385 and 2.28 collision m.f.p.'s for vertically incident proton- and iron-primaries, respectively. We detected 381 showers using Fuji-#200-type X-ray film; of these 174 showers were due to atmospheric secondary γ-rays, and the rest 207 came from nuclear components. The energy range covers 20∼200 TeV for proton-primary, 3∼30 TeV/nucleon for helium-primary, and 0.7∼5 TeV/nucleon for iron-primary. We give the energy spectra for various elements (proton, helium, …, iron) as well as the all-particle spectrum and the average mass of the cosmic-ray primaries.

We consider the dynamics of an electron cloud with an initially Maxwellian electron distribution and a temperature significantly exceeding that of the surrounding plasma. It is demonstrated that only the fastest electrons propagate into the plasma as a beam-plasma structure, whereas the main part of the cloud of electrons is locked by the Langmuir turbulence generated by the electrons remaining.

The dispersion properties of slow electromagnetic surface waves propagating across a constant external magnetic field and along a plane plasma-metal interface at harmonics of the ion cyclotron frequency are studied. The motion of the plasma particles is described by a Vlasov-Boltzmann kinetic equation. The effects of the plasma size, the dielectric permittivity of the transition region between the plasma and metal, and the magnitude of the constant external magnetic field on the dispersion characteristics of ion surface cyclotron waves are studied.

The dynamics of an electron beam is considered when the initial electron distribution is localized in a space region. Analysis is conducted for the parameters of the beam and plasma that give radio emission. We demonstrate both numerically and analytically that beam electrons propagate as a beam-plasma structure at large distances. The speed of the beam-plasma structure is equal to half of the maximum velocity of the electrons involved in this structure. The structure conserves the shape of the initial spatial distribution of electrons. A plateau with a constant maximum velocity is formed at the electron distribution function in each spatial point.

Parametrical excitation of surface type X-modes (STXM) at the second harmonic of electron cyclotron frequency by nonmonochromatic external alternating electric field is under consideration. STXM are the eigenmodes of a planar magnetoactive plasma waveguide structure consisting of a metal wall with dielectric coating and uniform plasma filling. An external steady magnetic field is applied along the plasma interface, so it is perpendicular to the group velocity of the considered extraordinarily polarized waves. Influence of the plasma waveguide parameters on the parametrical instability of the STXM is studied. External alternating electric field is assumed to consist of two fields with different amplitudes and frequencies. A theoretical investigation is carried out using kinetic equation for plasma particles under the conditions of weak plasma spatial dispersion and small amplitudes of external electric fields. The obtained results can be useful for research in branch of edge plasma physics.

The temporal plasmon-polariton echo in a semiconductor bounded by a metal is examined in a hydrodynamic approximation. The studied surface wave is localized near the semiconductor-metal interface and propagates across the external magnetic field. The initial surface-type pulse is modulated by a later applied second one of different wavelength to yield the non-vanishing echo signal. The values of the echo generation time and of electromagnetic fields of plasma responses are obtained. The obtained results may be used in a solid-state surface spectroscopy.

The hydrodynamic echo on the surface helicon-type modes radiated to vacuum in a magnetized plasma with steepened density profile is investigated. It is shown that perturbations induced by an initial pulse at the plasma boundary are modulated by a later applied second pulse of different wavelength, to yield a non-vanishing echo signal, which can be radiated to vacuum. The angle of the radiation and the density of the energy flow of this signal are determined.

The propagation of ion-cyclotron waves in an extended cylindrical plasma is analyzed analytically. The results obtained show progress in constructing a two-dimensionally-nonuniform analytical theory.

The results of experimental investigations of thermal conditions features of metal hydride cathodes of Zr‐V system in the Penning discharge are given. Increase of erosion resistance and a softening of a thermal conditions of electrode operation is revealed. The given effect is attained as due to thermal decomposition hydride phases, and a energy dissipation of beams of bombarding particles on the gas target which is shaped by desorpted hydrogen. It is set, that for stabilization of electrode temperature at a level 150°C the quantity of metal hydride compound makes 1 g/J.

Results of investigations of collective trap formation for a tubular electron beam which propagates in the conducting cylinder with a longitudinal magnetic field are submitted. It is shown that collective trap forms due to the double potential sag occurrence. Long lived particles accumulation may be theoretically described in the terms of shearless electron tubular beam rotation.

Dependence of efficiency and output power on parameter which is equal to ratio of total emission power to accumulated energy is considered in simplified model of gyrotron. It is shown that this parameter changes with changing of emission conditions at the generator output, which leads to the change of field distribution inside of gyrotron as well. Behavior of efficiency and output power is introduced in the vicinity of their maximal values.

In this paper we theoretically investigate phenomenon experimentally observed in [2]: reflection of a relativistic electron beam of finite length and small radius from vacuum‐plasma boundary. We suppose that self‐focusing of electron beam has been finished. The electron beam reflection on electron time scale is also considered. So plasma ions are fixed in space, but plasma electrons are accelerated in transversal direction. Thus a positive charge appears around the beam. The longitudinal shape of the electric potential is formed by electron beam and positive charge at separation of the beam back front from the plasma boundary. It was shown that this electric potential profile can be cause of reflection of an electron beam part from the plasma boundary. Dependence of the electric potential profile from a beam penetration depth and ratio of the plasma and beam parameters are obtained.

Investigations of reflective discharge in hydrogen medium using sectioned hollow cathode are carried out. As constructive elements of the hollow cathode an alloy Zr50V50Hx able to absorb hydrogen reversibly was used. It has been shown that in case of applying of metal‐hydride hollow cathode the penetration of plasma in the hollow occurs deeper. The possibility to operate the plasma penetration into the hollow cathode by means of potential variation on its sections was investigated.

Parametric excitation of surface cyclotron waves by a non-monochromatic variable electric field is studied numerically under the conditions of weak plasma spatial dispersion and small amplitudes of the pumping electric field. By using nonlinear boundary conditions an infinite set of equations for the initial stage of the parametric instability is obtained. The effect of the considered plasma waveguide system on the instability growth rates is studied.

Based on solar corona radio emission, the authors consider the propagation of two electron beams in a plasma within the quasilinear theory of weak turbulence. The propagation is based on the 1D kinetic equations of quasilinear theory.

A study has been made on the effects of an external alternating electric field on surface cyclotron waves in a semiinfinite plasma in a steady magnetic field parallel to the boundary. Calculations are performed on the increments for the parametric instabilities in the extraordinary ion and electron surface cyclotron waves under conditions of weak spatial dispersion.

Alkaline-earth-titanate-based electronic ceramics are widely used in the fabrication of modern products such as capacitors, varistors, thermistors, etc.1,2 The sintering of electronically active ceramics is one of most complicated and critical operations that determine the performance and cost characteristics of such products. To gain a deeper insight into the mechanisms of the sintering of the above materials and to explore the ways of promoting this process, we studied both experimentally and theoretically mass transfer processes in sintering alkaline-earth titanates.

Studies of the spectrum of the sun’s radiation in the submillimeter wavelength range are of considerable interest for the determination of the physical conditions in the lowest layers of its atmosphere (temperature, active regions) [1] and for the detection of highly ionized atoms of heavy elements in the solar corona [2]. The sun, as the most intense source of extraterrestrial submillimeter radiation, is at the same time an appropriate subject for tests of spectroradiometers of this range.

As is known, measurements of the polarization characteristics of radiation which is received in parallel with the study of its spectral composition provide valuable information of the phenomena and processes in which this radiation takes part. The interest in various devices which permit the analysis and measurement of the state of polarization of radiation in a wide region of the spectrum is understandable in this connection.

The possibility of studying the radiation of discrete astronomical sources in the submilli-meter range of the spectrum using an on-board telescope is determined to a considerable extent by the threshold sensitivity of the instrument, which depends entirely on the size of the mirror and the threshold sensitivity of the radiation receiver. Estimates of the expected fluxes from sources [1] and of the efficiencies of telescope optical systems [2] show that with a mirror diameter of 1.5 m the radiation receiver must have a threshold sensitivity no worse than 10−11 W/Hz1/2 at a width of 1000 GHz for the region of sensitivity in order to reliably record the radiation of a number of interesting sources [1]. To cover the greatest possible part of the submillimeter range with one instrument it is desirable to use a wide-band receiver. The necessity of mounting the instrument on board a flying vehicle imposes a number of specific requirements: relatively small overall size, weight, and energy consumption and stability against vibrations and accelerations.