PROGRESS IN THE STUDY OF DECAMETER-WAVELENGTH SOLAR RADIO EMISSION WITH UKRAINIAN RADIO TELESCOPES. Part 2

Subject and Purpose. This part of the paper continues presentation of results of the solar radio emission studies performed with Ukrainian radio telescopes over the past 20 years. The importance is stressed of developing adequate instruments and methods for identifying the nature of decameter-wavelength radio emissions from the Sun. Methods and Methodology. The low frequency Ukrainian radio telescopes UTR-2, GURT and URAN-2 have been used in the project along with other ground- and space based instruments in order to achieve a comprehensive understanding of physical conditions in the solar corona. Results. Special methods and tools have been developed for studying radio frequency burst emissions against the background of strong interference. Unique data have been obtained concerning sources of sporadic radio emissions from the Sun, as well as the contribution from wave propagation effects and the impact of the ionosphere on the results of observations. The most significant observational and theoretical results are presented, obtained in the study of solar low frequency emissions over the past 20 years. Solar radio emissions are shown to be efficient sounding signals not for the solar corona alone but for the Earth’s ionosphere as well, which allows identifying its impact on the results of radio astronomy observations. Conclusions. The Ukrainian radio telescopes of the meter and decameter wavebands currently are unrivaled tools for investigating the Universe in the low-frequency range of radio waves. Owing to their advanced characteristics, they make a significant contribution to the progress of world’s solar radio astronomy

PROGRESS IN THE STUDY OF DECAMETER-WAVELENGTH SOLAR RADIO EMISSION WITH UKRAINIAN RADIO TELESCOPES. Part 1. (Invited paper)

Subject and Purpose. Results are presented of the solar corona investigations performed with the world famous Ukrainian radio telescopes. The work has been aimed at offering a consistent review of recent achievements in observations of a variety of low-frequency radio emissions from the Sun. Methods and Methodology. The studies of the quiet (thermal) and sporadic (burst-like) radio emissions from the Sun have been carried out with the decameter-wavelength radio telescopes UTR-2, GURT and URAN-2. Specific features of the low-frequency solar radio emissions from a variety of sources are presented, with characterization of the optimized techniques that were applied in each case for evaluating physical parameters of the corona in the areas of decameter-wavelength radio wave generation. Results. The analysis of temporal, frequency and spatial characteristics of solar radio emissions has allowed suggesting a number of models for the coronal electron density distribution, and evaluating magnetic field strengths in the corona. Also, our experimental results have proven to be consistent with the observational data obtained in different frequency ranges and with the use of both ground based and space-borne instruments. Conclusions. The radio observations performed with Ukrainian radio telescopes have permitted studying, with high temporal, frequency and spatial resolutions, solar radio frequency emissions from various localized sources. Along with the large effective area and high sensitivity of the antennas, this permits application of a wide range of methods and tools aimed at detecting and analyzing solar bursts, of both strong and weak intensity, against the background of terrestrial interference of natural or artificial origin

The analysis of methylation of DNA promoter of SFRP2 gene in patients with hyperplastic processes of the endometrium

The hyperplastic processes of the endometrium can arise not only against the background of excessive influence of estrogen, but also against the background of epigenetic damages that affect apoptosis, cell proliferation, differentiation, and adhesion, and DNA reparation. The aim of our study was to investigate and analyze the status of methylation of the promoter of SFRP2 gene in patients with hyperplastic processes of the endometrium. Materials and Methods: The study groups were the following: I — patients with endometrial hyperplasia (EH, n = 9); II — patients with endometrial intraepithelial neoplasia (EIN, n = 10), III — control groups: 1) with endometrial cancer (EC, n = 4), and 2) healthy women (n = 4). Determination of promoter methylation of SFRP2 gene was carried out by the semiquantitative method of methylation-specific PCR assay. Results: The maximum level of methylation of SFRP2 gene promoter had been revealed in patients with EC — 42.80 ± 3.55% (р < 0.05). The patients of the I group had the lowest values of methylation of SFRP2 gene promoter — 10.66 ± 0.85%, while in patients of the II group this indicator was higher — 20.60 ± 0.95% (р < 0.05). In healthy women of the control group, methylation of SFRP2 gene promoter was detected in none of the samples. Conclusion: The content of the methylated SFRP2 gene in endometrial tissue of patients with hyperplastic processes higher than 20–25% allows relate these women to the risk group of EC development and dictates the need of intensive observation of such patients

Comparison of the results of surgical treatment of patients with Achilles tendon injury at Myerson stage II and III diastasis using plantar muscle flexor tendon

Single-center randomized controlled partially blinded research aimed at the determination of functional results of surgical treatment of patients with Achilles tendon injury of different Myerson stages was carried out in the clinic of Irkutsk Scientific Centre of Surgery and Traumatology. Based on the analysis of surgical treatment of 20 patients with Achilles tendon divided into two groups (with Myerson stage 11 and stage 111 diastasis) we showed the effectiveness of surgical treatment using plantar muscle flexor tendon. We assessed the following criteria: 1) time from the moment of injury, diastasis length, duration of surgery; 2) pain syndrome after the surgery, omission of additional mobility aids and equipment; 3) AOFAS functional results. While the analysis we found statistically significant differences in studied groups by the criteria "time from the moment of injury" and "diastasis length". As the result of the research we found statistically significant differences by "duration of surgery» criterion. In consequence of using plantar muscle flexor tendon as a stabilizing factor at the restoration of Achilles tendon we didn't register the differences between the groups by the level and duration of pain syndrome after the surgery, terms of the omission of additional mobility aids and equipment after the surgery and also in AOFAS functional results

Primary plasty of an Achilles tendon by plantar muscle tendon (clinical case)

Patient T., 43 years old arrived in clinic with complaints to the pains in lower thir of the right shin, limitation of movements in right ankle joint, inability of using right lower extremity. An. operative treatment was realized in clinic: suture of rupture of Achilles tendon by Cuneo with plastics by the tendon of long plantar muscle. In 4 weeks plaster immobilization was removed, the patient started measured loading of operated extremity with additional cane support. In 6 weeks full load on operated extremity was allowed and the patient returned to work. In 2 months patient received repeated trauma. During the examination local painfulness in the area of operative intervention was revealed. At the palpation it was revealed that integrity of plantar muscle tendon isn't broken. Control MRR of right shin was made: as the result of control examination the injury of plantar muscle tendon wasn't revealed. Immobilization of operated extremity in neutral position of a foot by functional brace was recommended to the patient. Measured, loading with additional additional cane support was approved. In 2 weeks the immobilization was removed, function of operated extremity is fully restored. Conclusion: if proposed method allows to start earlier loadings and. to decrease possibility of repeated rupture of reconstructed plantar muscle tendon in the most active period of rehabilitation

Primary plastics of Achilles tendon by plantar muscle tendon for the prevention of repeated ruptures (experimental research)

The most important requirement to Achilles tendon suture is its ability to hold loading both in postoperative and. in rehabilitation period. The research was aimed, at the comparison of strength of classic intertendon suture of Achilles tendon and. primary plastics of Achilles tendon by plantar muscle tendon. 60 unfixed (cadaveric) Achilles tendons and 60 plantar muscle tendons were used in experimental research. Further parameters were registered: age, measurements of Achilles and long plantar muscle tendons (length, width, thickness). The first step was to determine the tensile of intact Achilles tendon; the second was to determine the tensile double Polyester N 6 suture; the third — to determine tensile of plantar muscle tendon; the fourth — to determine tensile of Achilles tendon reconstructed with, use of proposed method. As the result of the experiment further conclusions were drawn. 1. Force that causes rupture of Achilles tendon decreases with age of a person that proves degenerative theory of Achilles tendon injury indirectrly. 2. Force that causes rupture of intact Achilles tendon (Ме) is 161,0, of double Polyester N 6 suture — 5,0, of tendon of plantar muscle folded up in four is 22,5; of Achilles tendon reconstructed with use of proposed method is 32,0. 3. Tensile of primary plastics of Achilles tendon sutured with use of proposed method is 6.4 times more than tensile of classic suture (Polyester N 6)

Digital receivers for low-frequency radio telescopes UTR-2, URAN, GURT

This paper describes digital radio astronomical receivers used for decameter and meter wavelength observations. This paper describes digital radio astronomical receivers used for decameter and meter wavelength observations. Since 1998, digital receivers performing on-the-fly dynamic spectrum calculations or waveform data recording without data loss have been used at the UTR-2 radio telescope, the URAN VLBI system, and the GURT new generation radio telescope. Here we detail these receivers developed for operation in the strong interference environment that prevails in the decameter wavelength range. Data collected with these receivers allowed us to discover numerous radio astronomical objects and phenomena at low frequencies, a summary of which is also presented.Comment: 24 pages, 15 figure