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The possibility of neutron generation by irradiating deuterated crystalline structures with an electron beam with an energy of 20–40 keV was studied. As targets, the deuterated crystalline structures of palladium and textured CVD diamond were used. Measurements of neutron emission are presented, which were carried out by three independent methods—scintillation detectors, counters based on He-3, and track detectors CR-39.The average neutron flux during irradiation was estimated as 1–10 s $${}^{-1}$$ in 4 $$\pi$$ sr.

The results of measurements of the dependence of the full width at half-maximum and the relative intensity of spectral peaks of parametric X-ray radiation (PXR) for various crystallographic planes on the grain size of a micrometer diamond powder are presented.

The formation region effects in x-ray transition radiation have been experimentally investigated. The radiation was generated using 1–6 GeV electrons impinging on two multilayer targets with considerably different periods. The absolute yield of transition radiation was measured and the wide spectral peak in the range from 10 to 30 keV was observed. In the most part of the electron energy range the emission from the short-period radiator was expectedly suppressed, compared to the case of the long-period one. But for the electron energy of 1 GeV an opposite effect, though rather small, of the emission enhancement in the short-period radiator was observed. The conditions, under which this effect is much stronger, are derived and its possible practical value is outlined. The theory accounting for an arbitrary transversal shape of the electron beam and the finite size of the detector is developed. This theory describes rather well the experimental results.

This article presents the immediate results of the treatment of patients with locaiiy advanced cancer of the oropharyngeal region, using the new puncture cryodestruction technique and standard surgical treatment. The overall and one-year disease-free survival rates of patients with locally advanced cancer of the oropharyngeal region were evaluated. The analysis of disease progression data in the main and in the control groups was carried out.

A pyroelectric X-ray source is proposed, in which a lithium tantalate crystal is heated by an infrared laser with a wavelength of 10.6 μm. X-ray spectra measured during irradiation of the crystal with infrared radiation and during natural cooling of the crystal include characteristic X-ray radiation of atoms contained in the structural parts of the source, as well as bremsstrahlung of electrons with energies above 50 keV. An 8 mm sodium chloride window was used to inject 64 W infrared radiation into a vacuum chamber with the pyroelectric crystal installed.

Текстура поликристаллической фольги вольфрама и никеля изучалась с использованием параметрического рентгеновского излучения (PXR), генерируемого электронами с энергией 7 МэВ. Получены кривые качания PXR из кристаллографических плоскостей (200) для вольфрама и (220) для никеля. Приведено сравнение с аналогичными измерениями, полученными с использованием дифракции широкополосных рентгеновских лучей. Сравнение показало хорошее соответствие результатов, касающихся формы кривых качания и положения максимумов. Однако наблюдалось систематическое несоответствие в значении полного максимума полной ширины.

The features of 10-keV electron propagation through a cylindrical channel made of borosilicate glass are experimentally studied. Experimental results indicate that a fast electron beam can be controlled using tapered capillaries fabricated from the given material. The charge distribution formed inside the channel provides conditions under which no less than 20% of beam electrons pass through the channel without considerable energy losses even if the inclination angles exceed the geometric angle of transmission.

The Rontgen-1 setup which is intended for use in investigating the spectral-angular characteristics of X-rays generated due to the interaction between a 7-MeV electron beam and substances, including different shaped surfaces, is described. The setup is distinguished by a low radiation background, enabling the determination of low-intensity radiation spectra. The results of measuring the characteristics of the polarized bremsstrahlung of relativistic electrons from media with different atomic structures are presented.

The K-shell ionization cross sections of titanium and copper atoms were determined by analyzing the spectra of characteristic X-ray radiation generated by an electron beam with energies of 1 and 2 GeV in metal foils. New data obtained for these energies demonstrate the influence of the density effect on the ionization cross sections values. The results were compared with previous experimental data and calculations based on pure theoretical and semi-empirical models.

The possibility of the measurement of proton ionization loss in the Silicon (Si) layer of smoothly tunable thickness was demonstrated in an experiment with a 50-GeV proton beam. The Si surface-barrier detector with the depleted layer thickness controlled by the value of high-voltage power supply was used in the experiment. The measured spectra of ionization loss are discussed and compared with the calculated spectra. The possibilities of research of the evolution of electromagnetic field of ultrarelativistic particles traversing the media interface and the study of dynamics of particles moving in the channeling regime or the volume reflection regime with the use of detectors with smoothly tunable thickness are indicated.

The possibility of measurement of electrons ionization loss in Si layer of smoothly tunable thickness is shown in the proof-of-principle experiment. The Si surface-barrier detector with the depleted layer thickness controlled by the value of high voltage power supply has been used. Ionization loss spectra for electrons emitted by radioactive source 207Bi are presented and discussed. Experimental results for the most probable ionization loss in the Landau spectral peak are compared with theoretical calculations. The possibility of research of evolution of electromagnetic field of ultra-relativistic particles traversing media interface with the use of detectors with smoothly tunable thickness is proposed.

A beam of six-charged carbon ions with an energy of 24.8 GeV/nucleon is extracted from the U-70 synchrotron by means of a silicon crystal bent through 85 mrad. A total of 200000 particles are observed in beamline 4a upon forcing 109 circulating ions to the crystal. The geometrical parameters, timing structure, and composition of the beam have been measured. It has been shown for the first time that, using a bent single crystal, an ion beam with required parameters can be extracted from the accelerator ring and formed for regular use in physics experiments.

A series of experiments is carried out to study the passage of electrons with an energy of 10 keV through glass macrocapillaries of tapered shape with an input—output diameter ratio of 1 : 10 and 1 : 5. Experiments are performed for different tilt angles of the capillaries with respect to the incident-beam axis. The results demonstrate a significant increase in the current density of a beam passed through the capillaries.

The results of an investigation of the passage of 10-keV electron beam through dielectric channels fabricated from ceramic (zirconium dioxide) and pyroelectric crystals (lithium niobate) are presented. The angle of deflection of the electron beam by the channels was measured as a function of the angle of interaction of the beam with the internal walls of the channels. The obtained results indicate the possible prospects of using dielectric surfaces as effective deflectors of accelerated charged particles.

The problem of restoring tissue defects after radical surgery for malignant tumors of the head and neck remains relevant, as there is no standardized approach for solving this problem. This article describes the various options for plastics of combined through defects of the floor of the mouth, of angle of the mouth, of the upper and lower lips, of lateral parts of the neck. The use of a particular type of arterialized flap depended on the depth and character of the existing tissue defect. The use of this methodology allowed to reach satisfactory cosmetic and functional results, as well as improve the quality of patient’s life.

Ultrasound scan allows determining tumor border in the area of inflammatory infiltrate, creating a three-dimensional plan of the operation, performing accurate pointing injecting cryoprobes as well as managing a monitor of cryoablation. As a result the frequency of repeated recurrences of infected recurrent tumors in difficult anatomical areas of the face decreased to 4%.

The results of the experimental observation of characteristic X-ray radiation (CXR) excited in solid targets by the extracted and circulated 450 MeV/u C+6 ions beams and circulating 1.3 GeV protons beam are presented. The spectra of X-ray radiation measured from different targets are presented and discussed. It was found that the background radiation near the beams is low enough that allows the observation of the CXR spectral peaks with energies from a few to tens keV by semiconductor X-ray detectors. Applications of the CXR for monitoring of the number of accelerated particles in experimental applied and basic research, including radiobiology and radiation medicine as well as the relativistic nuclear physics and steering of beams by bent crystalline deflectors are proposed.

A set of experiments to study the guiding of 10 keV electrons by tapered glass capillaries was performed. It is shown that the 10 keV electron beam can be tightly focused by the tapered macrocapillaries. The charge/discharge processes of the capillary inlet are shown and discussed. The guiding effect was obtained for 10 keV electrons by a tapered glass capillary of a simple shape. The electron beam transmission was measured for several angles.

The effect of guiding a 10-keV electron beam using dielectric plates is studied. It is shown that the electron beam after interaction with the insulator surface is deflected by this surface in different ways depending on a variety of grounding schemes of the front and back sides of plexiglass and aluminum-oxide plates. The dependence of the deflection of the beam from the plexiglass plates at different angle positions on the incident electron-beam current value is studied.

For the first time a classical model was developed to describe quantitatively the dynamics of charge distribution formation on a planar dielectric surface during its irradiation by fast electrons at a grazing incidence. The dynamic effects of the mutual influence of the beam and the dielectric surface charge predicted by the developed model are in a good agreement with the performed experiments. The proposed model can be used to describe time dependent processes of the electron beam–dielectric surface interaction, charging up and discharging for dielectric channels of more complex shapes.

Experimental setup designed for studying the processes occurring under fast electrons interaction with a matter is presented. The setup is based on an electron gun, which produces the electron beam with current in range from 10 nA to 5 µA and electrons energies from 8 up to 60 keV. The rest parts of the setup are the electron gun chamber, electromagnetic system for the electron beam formation, target vacuum chamber, target goniometer, equipment for the beam diagnostics and spectrometry.

The measurements of X-ray polarization’s bremsstrahlung in the back scattering geometry (PBBS) generated during the interaction of 7 MeV electrons with polycrystalline foils of copper and niobium were performed. The analysis has shown a good agreement of the spectral width and position of the peaks with the theoretical calculations. The obtained results confirm the availability to develop a new method based on the PBBS peaks measurements for diagnostics of materials with a polycrystalline atomic structure.

The collimated spectra of polarization bremsstrahlung (PB) produced by 7 MeV electrons in Al, Ni, Cu, Mo and W poly crystalline foils are measured and the angular dependences of the PB characteristics are studied. A comparison of the experimental results with theoretical predictions is performed. Polarization bremsstrahlung sensitivity to texture and grain size of the target in the backscattering geometry is shown. The possibility of developing a new method based on the characteristics measurement of the coherent PB component for the diagnostics of polycrystalline materials is considered.

The possibility of using PZT-19 ceramic in a pyroelectric x-ray generator is investigated experimentally. Measurements of the x-ray spectra showed the possibility of obtaining on a ceramic surface in vacuum potentials up to 7 kV, which is very low compared with typical similar values for pyroelectric crystals of lithium niobate and tantalate. This feature is due to the significant permittivity of the ceramic. It is shown that the main criterion for picking a ceramic for a pyroelectric x-ray generation could be the maximum value of the ratio of the pyroelectric constant to the permittivity.

OBJECTIVE To improve the algorithm of differential diagnosis and complex treatment of patients with CR. MATERIAL AND METHODS Forty-two patients with CR were divided into 2 groups. Patients of the first group (n=21) received basic treatment (NSAID, myorelaxants, local injections with glucocorticoids (on demand), B vitamins and non-pharmacological methods) and the anticholinesterase drug ipidacrine. The second group (n=21) had only basic treatment. The total duration of the study was 45 days. The effectiveness of treatment was evaluated with VAS, NDI, GROC and total duration of disability period. RESULTS A battery of tests for the diagnosis of CR that included Spurling test, motor strength deficiency, ULTT, pain pattern, shoulder adduction test (diagnostic complex SPASIBO), has been developed. A positive result of all 5 tests guarantees the 94.7% accuracy of CR diagnosis. The application of ipidacrine has allowed a significant (p

The characteristics of a possible radiation source in the vacuum-ultraviolet and soft X-ray range based on the transition radiation of electrons with an energy of about 100 keV are calculated. The possibilities of enhancing the radiation yield in the geometry of the glancing interaction of electrons with a target are analyzed. The possibility of creating a source with a yield on the order of 10−5 photon/(eV sr) per electron is demonstrated.

The grazing incidence interaction of a 10-keV electron beam with a planar surface of plexiglass is studied experimentally. Moreover, the electron passage through flat channels formed by such surfaces is investigated. The experiments reveal the presence of a guiding effect of the electron passage as in the case of a glass surface. However, there are some features, such as the existence of an initial elevation angle for the case of negative inclination angles of the plate. The formation of self-consistent charge on the surface of the plexiglass and its drain when the current is turned off occur more slowly than on the glass surface. This fact points to the difference in the surface conductivity of insulators.

The spectra of polarization bremsstrahlung are measured in the backscattering geometry during the interaction of 7-MeV electrons with a polycrystalline Ni foil. Measurement is conducted under conditions such that the size of the region of coherent X-ray radiation scattering in a target is on the order of 10 nm. The obtained results make it possible to suggest that using polarization bremsstrahlung as a new method for the diagnostics of the atomic structures of nanodisperse polycrystals is effective.

The effect of the contactless transmission (guiding) of 10 keV electrons through cylindrical dielectric channels and planar channels formed by glass plates is studied. The capture and propagation of an electron beam along the channel axis, usual in these cases, are observed in the experiments with two plates. The deviation of the reflection angle from the specular angle and its dependence on the plate length and beamcurrent value under beam reflection from a single plate are investigated.

Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used for treatment of pain, fever and inflammatory diseases. However, along with a high rate of efficacy, NSAIDs have been associated with an increased risk of gastrointestinal and cardiovascular complications related to the inhibition of the enzymes cyclooxygenase 1 and 2. The review addresses contemporary mechanisms of NSAID's side-effects and analyzes clinical trials of the efficacy and tolerability of aceclofenac, which is the most frequently prescribed NSAID, as in its traditional release form (100 mg 2 times a day) as well as in the controlled-release (200 mg a day) form.Нестероидные противовоспалительные средства (НПВС) широко используются во всем мире в лечении боли, гипертермии и воспаления. Однако наряду с высокой эффективностью применение НПВС ассоциировано с увеличением рисков гастроинтестинальных и кардиоваскулярных побочных эффектов в несколько раз, что связано с ингибированием активности циклооксигеназы 1-го и 2-го типа. В обзоре рассматриваются современные механизмы развития побочных эффектов на фоне приема НПВС, анализируются данные клинических исследований, в которых изучали эффективность и переносимость одного из наиболее распространенных препаратов из данной группы - ацеклофенака, используемого как в традиционной форме выпуска (100 мг 2 раза в день), так и в форме с контролируемым высвобождением действующего вещества (200 мг 1 раз в день).

A multi-wirescanner for diagnostics of ionizing particle beams (e.g. both non-relativistic and ultra-relativistic charged particles; X-ray and gamma photons) is proposed and discussed in the paper. The scanner is based on measurement of yield of characteristic X-rays generated during the particle interaction with the wires made of different materials. The proposed scanner is developed and tested on the beam of electrons with energy of 40 keV . The quasimonochromatic characteristic X-rays and continuous background are clearly identified. The results of measurements of the transverse size, emittance, position and direction of beam propagation are presented and discussed.

The spectrum of polarization Bremsstrahlung is measured in backscattering geometry for 7-MeV electrons and a polycrystalline Ni foil without texture. The average size of grains in the foil is 300 nm. The results show the possibility of using a new method in the diagnostics of the atomic structure of polycrystalline materials with nanosized grains. The method is based on measuring the coherent component of polarization Bremsstrahlung.

The spectra of polarization bremsstrahlung (PB) in the X-ray range induced by 7-MeV electrons in a polycrystalline copper target have been measured in the backscattering geometry for various orientations of the target relative to the electron beam. It is shown that the PB backscattering is sensitive to the texture of a target. The possibility of developing a new method based on the measurement of characteristics of the coherent PB component for the diagnostics of polycrystalline materials is considered.

The enhancement of the yield of parametric X-ray radiation from 7-MeV electrons incident at a grazing angle on the silicon crystal surface has been experimentally detected.

The paper presents the results of a theoretical study and a mathematical model of radiation processes occurred during the grazing interaction of fast electrons with semi-infinite targets applied on a thin amorphous layer. The developed model considers Vavilov-Cherenkov and transition radiation mechanisms and predicts the possibility to enhance the angular radiation density under grazing incidence of fast electrons on the layer. The characteristics of possible extreme vacuum ultraviolet and soft X-ray sources are estimated.