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An article in the education system, the use of new information and communication technologies in the process of theoretical and practical issues and is described in more detail on the international experience in this field.

SbxSey films were obtained by chemical molecular beam deposition (CMBD) on soda-lime glass substrates. Sb and Se were used as sources, their evaporation temperature was 950–1000°C (Sb) and 500°C (Se), the substrate temperature was maintained at about 500°C. Using scanning electron microscopy, X-ray diffraction analysis, and Raman scattering, the effect of the Sb/Se composition ratio on the structure of the synthesized films was studied. It was revealed that the films have a crystalline (orthorhombic) structure with compactly located crystallites having the form of rods with an average size: l = 4–8 µm (length) and d = 2–3 µm (diameter). [ABSTRACT FROM AUTHOR]

High-quality crystalline Sb2Se3 films are fabricated by the chemical molecular beam deposition (CMBD) method from separate sources of Sb2Se3 binary compound and Se element, at a substrate temperature of 500°C. The effect of temperature of the selenium source on the morphological, structural, optical, and electrical properties of Sb2Se3 films has been studied. Based on the scanning electron microscope images and XRD analysis data, it is revealed that all films have a polycrystalline orthorhombic structure, and the crystallite sizes are 5–10 μm. The electrical conductivities of the films vary within 1.03 × 10–5 to 4.13 × 10–5 (Ω cm)–1 depending on the ratio of Sb/Se atomic concentration. These results determine the growth of high-quality Sb2Se3 thin films from separate sources of the Sb2Se3 binary compound and the Se element at a substrate temperature of 500°C and are the main factors for obtaining efficient solar cells based on Sb2Se3 using the CMBD method. [ABSTRACT FROM AUTHOR]

This paper presents results of the transmittance, photoacoustic and surface photovoltage experiments performed on the series of CdS1 – xTex thin films. These CdS1 – xTex (0 ≤ x ≤ 1) thin films were obtained on the glass substrate by the chemical molecular beam deposition (CMBD) method. From the experimental optical characteristics, the optical absorption coefficient spectra of the samples and values of the energy gaps vs. composition of the crystals were determined. The energy gaps of the layers changed from 2.44 to 1.34 eV. From the photo voltage characteristics, the diffusion lengths of the carriers were determined. They changed from 5 to 17 µm what can indicate a good quality of the layers. [ABSTRACT FROM AUTHOR]

Imperfections in the state administration of Uzbekistan are examined. Economic and political factors responsible for these imperfections are also analyzed.

Currently, not only in crop production but also in the crops of medicinal plants, biostimulants are increasingly being used. It is known that biostimulants can influence important physiological processes in plant life: rooting, acceleration of photosynthesis, growth, and development, acceleration of early flowering, increase in the number of flowers, fruit ripening, etc. Most species of the genus Astragalus are a valuable source of biologically active substances, in turn, their accumulation occurs both in the aerial parts and in the rootsof plants. The research aimed to study biostimulants for the accumulation of plant phytomass A. babatagi and A. xanthomeloides in the conditions of the Tashkent region. The work was carried out in the Quyichirchik district of the Tashkent region in 2023. The analyzes were carried out on A. babatagi and A. xanthomeloides plants grown fromseeds treated with biostimulants Uchkun plus and Potassium Humate Souffler. The harvesting of raw plant phytomass was carried out in the phase of intensive flowering. Pre-sowing treatment in A. babatagi crops provided an increase in the yield of raw biomass in the "scarification + Uchkun plus" experiment by 25.2%, in the "scarification+ Potassium Humate Prompter" option by 17.3% relative to the "scarification" option. The increase in the biomass yield of A. xanthomeloides in the variant of the experiment "scarification + Uchkun plus" was 15.8% and "scarification + Potassium humatePrompter" - 17%, respectively. As our studies have shown, the use of presowing seed treatment of A. babatagi and A. xanthomeloides with biostimulants Uchkun plus and Gumat potassium Souffler contributed to an increase in the yield of raw plant phytomass. [ABSTRACT FROM AUTHOR]

The scientific research illustrates that the eigenfrequencies of vibrations of an elastic spherical layer located in an infinite elastic medium are investigated. The problem of natural and forced oscillations is solved by reduction to a plane problem of elasticity theory. The spectrum of complex natural frequencies for spherical mechanical systems in an elastic medium is obtained in this work depending on various geometric and mechanical parameters of the system.

(ZnSe)x(SnSe)1–x films have been produced using chemical molecular beam deposition (CMBD) from an ZnSe and SnSe compound with a stoichiometric composition at a substrate temperature of 500°С. The structural, morphological, and electrophysical properties of (ZnSe)0.1 (SnSe)0.9 films are studied. The size of film grains is 5–6 μm. The results of X-ray diffraction analysis of specimens have revealed that the films have a crystalline (orthorhombic) structure. The structural parameters of the produced films are presented. The electrical conductivity of the films measured using the Van der Pauw method varies within 15–0.6 Ω cm–1. [ABSTRACT FROM AUTHOR]

CdTe films of different compositions were grown by the chemical molecular-beam deposition method. The activation energy and the nature of deep levels in relation with the composition of films based on the temperature dependence of electroconductivity are defined, and the influence on these levels of heat treatment process in CdCl2 solution has been studied. Deep levels with the following activation energies are defined: Ev +0.31 eV; Ev + 0.42 ± 0.03 eV; Ec-0.44 ± 0.01 eV; Ec-0.28 eV; Ev + 0.24 ± 0.01 eV. [ABSTRACT FROM AUTHOR]

Objective: In narrow anterior urethral strictures, the combined buccal mucosa graft (BMG) with pedicled penile skin flap (PSF) represents a well-known effective alternative to staged urethroplasty. We hypothesized that if the native urethral plate and adjacent corpus spongiosum were preserved, a narrower flap would be needed, and reinforced ventral stability could be achieved without compromising the surgical outcome., Methods: Twelve patients with narrow penile urethral strictures underwent single-stage augmentation urethroplasty using a combined technique. A BMG was quilted to the corpora cavernosa in a dorsal onlay approach, and a longitudinal ventral PSF was transposed ventrally and sutured to the scarred native urethral mucosa on one side and to the BMG on the other side to form a neourethra of triangular form. The preserved corpus spongiosum was wrapped and fixed around the flap ventrally., Results: The median age was 47 years (IQR 35-59), and the median stricture length was 5 cm (IQR 3, 8-7). The median surgical time was 205 min (IQR 172-236). The overall success rate (SR) was 91.7% without sacculation or diverticula formation after a median follow-up period of 38 months (IQR 33-40). Three transient fistulas healed through prolonged urinary diversion. Five patients (41.7%) reported postvoid dribbling following urethroplasty., Conclusion: Preservation of the native urethral plate is a valuable adjunct to the combination of graft and flap for single-stage augmentation urethroplasty for narrow urethral strictures, with satisfactory mid-term success and an acceptable complication rate., (© 2024 The Japanese Urological Association.)

Objective: Our study aimed to compare surgical success rate (SR) and oral morbidity of augmentation urethroplasty for anterior urethral strictures using autologous tissue-engineered oral mucosa graft (TEOMG) named MukoCell® versus native oral mucosa graft (NOMG)., Methods: We conducted a single-institution observational study on patients undergoing TEOMG and NOMG urethroplasty for anterior urethral strictures >2 cm in length from January 2016 to July 2020. SR, oral morbidity, and potential risk factors of recurrence were compared between groups were analyzed. A decrease of maximum uroflow rate < 15 mL/s or further instrumentation was considered a failure., Results: Overall, TEOMG (n = 77) and NOMG (n = 76) groups had comparable SR (68.8% vs. 78.9%, p = 0.155) after a median follow-up of 52 (interquartile range [IQR] 45-60) months for TEOMG and 53.5 (IQR 43-58) months for NOMG. Subgroup analysis revealed comparable SR according to surgical technique, stricture localization, and length. Only following repetitive urethral dilatations, TEOMG achieved lower SR (31.3% vs. 81.3%, p = 0.003). Surgical time was significantly shorter by TEOMG use (median 104 vs. 182 min, p < 0.001). Oral morbidity and the associated "burden" in patients' quality of life were significantly less at 3 weeks following the biopsy required for TEOMG manufacture, compared to NOMG harvesting and totally absent at 6 and 12 months postoperatively., Conclusions: The SR of TEOMG urethroplasty appeared to be comparable to NOMG at a mid-term follow-up but taking into account the uneven distribution of stricture site and the surgical techniques used in both groups. Surgical time was significantly shortened, since no intraoperative mucosa harvesting was required, and oral complications were diminished through the preoperative biopsy for MukoCell® manufacture., (© 2023 The Authors. International Journal of Urology published by John Wiley & Sons Australia, Ltd on behalf of The Japanese Urological Association.)

Staged urethroplasty is performed to treat long-segment obliterating anterior urethral strictures. The technique is particularly challenging when the penobulbar junction is involved, as it requires the transection of the scrotum and the formation of lateral testicular fans. To date, there is no established surgical protocol for this ancillary technique in large volume scrotums with excess skin. We report a case of staged urethroplasty with the necessity of performing T-scrotoplasty due to bulky scrotum. After six months, the T-plasty was successfully resolved, and a new scrotum was formed from the two hemiscrota. In conclusion, scrotoplasty using a bilateral T-plasty is an excellent technique to overcome the necessity of splitting the scrotum by externalizing the urethra to allow for excellent buccal mucosal graft healing over a period of six months. The two separate testicular fans can be reapproximated along the raphe after re-tubularizing the urethra in the 2nd stage, shaping a new scrotum with satisfactory cosmetic results., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2022, Halbe et al.)