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Introduction. 3D concrete printing (3DCP), carried out with concrete and mortar mixtures based on mineral binders, including hybrid mixtures, is one of the promising methods for the concrete products industry. The analysis of the current state of research in the field of development of composite materials based on gypsum-cement-pozzolanic binder for 3DCP indicates the limitations of its use due to the short setting time of gypsum, as well as low water resistance and tensile strength of products based on it, which indicates the relevance of research, aimed at developing stable compositions of gypsum-cement-pozzolanic concrete for 3DCP, with high physical, technical and optimal rheotechnological characteristics.Materials and methods. The production of specimens was carried out on construction 3D printer “AMT S-6044” produced by “SPETSAVIA” LLC. Standard methods for studying rheological properties, physical and technical properties of concrete were applied.Results. The composition of gypsum-cement-pozzolanic concrete (GCPC) in 3DCP was theoretically substantiated and experimentally determined. Rational application of concrete with binder: aggregate ratio = 1:2, sand fineness modulus of Mk 3, providing the following characteristics of the control concrete composition: compressive strength — 22.1 MPa, bending strength — 4.9 MPa, average density — 1,892 kg/m3, dimensional stability 16 cm, ultimate shear stress 58.5 Pa was substantiated in 3DCP. The peculiarities of structure formation and some drawbacks of microstructure of the developed gypsum-cement-pozzolanic concrete formed by the additive manufacturing method were studied.Conclusions. Gypsum-cement-pozzolanic concretes were developed for 3DCP with an optimal ratio of components in the binder composition. The prospects for further improvement of GCPC compositions by modifying them with multifunctional complex additives were shown.

Introduction. Benign prostatic hyperplasia (BPH) is a multifactorial and widespread problem of modern medicine, which has not only medical but also social significance. The presence of lower urinary tract symptoms (LUTS) in men has a negative impact on the quality of life. One of the modern surgical methods for treating BPH is the use of laser technologies.Objective. To compare the effectiveness and safety of laser technologies using the example of the use of diode and thulium lasers in BPH surgery.Materials & methods. The study included 89 men with BPH who underwent surgery from 2020 to 2022. Patients were divided into two groups: in group 1 (n = 37) photoselective vaporization of the prostate was performed using a Diode Laser Vaporization of the Prostate (DiVAP), in group 2 (n = 52) - Thulium Laser Enucleation of the Prostate (ThuLEP). To assess the results of treatment, we studied indicators of maximum urine flow, residual urine volume, prostate volume, prostate-specific antigen level, severity of LUTS (IPSS scale) and symptoms of erectile dysfunction (IIEF-5 scale), level of quality of life (QoL index) and the frequency of postoperative complications. The outcomes were assessed at baseline and 3, 6, 12 months after the procedure. The duration of the operation, the duration of catheterization and the length of stay of patients in the hospital were also recorded.Results. At a long-term follow-up (12 months), the effectiveness of DiVAP and ThuLEP was comparable in terms of prostate volume (24.0 and 24.3 cm3), PSA level (3.3 and 3.4 ng/ml) and quality of life of patients related to urination (2.3 and 2.0 points). The severity of LUTS one year after treatment was also comparable in the groups (4.1 and 4.6 points), however, the IPSS scale scores was more favorable in the ThuLEP group at three- and six-month follow-up points (3 months: 14.9 and 10.0 points; 6 months: 9.3 and 7.5 points). At the same time, ThuLEP also turned out to be more effective in the rate of maximum urine flow achieved after a year (15.2 and 25.8 ml/s), the residual urine volume (8.2 and 2.2 ml), and IIEF-5 questionnaire score (22, 4 and 24.4 points), DiVAP - by operation time (58.5 and 84.6 minutes) and catheterization duration (26.8 and 32.5 hours). There were no statistically significant differences in the duration of hospitalization (2.2 and 2.1 days). Postoperative complications are recorded 2 times more often with DiVAP than after ThuLEP.Conclusions. The study confirmed the high efficiency of endoscopic laser enucleation (ThuLEP) and laser vaporization (DiVAP) technologies. The safety of ThuLEP is due to the lower incidence of postoperative complications compared to DiVAP. The success of laser operations directly depends on careful selection of patients, as well as the experience of the surgeon.

This paper explores the integration of computer vision techniques within medical database management systems, focusing on their potential to enhance data accuracy and operational efficiency in healthcare. The study analyzes current methodologies and proposes enhancements based on recent technological advancements, particularly in graphics processor architectures. The research employs a combination of theoretical analysis and computational modeling, with a detailed examination of the G80 graphics processor architecture. The Viola-Jones method is utilized as a model algorithm for object detection in medical images, implemented using the OpenCV library. The study evaluates the algorithm's performance on 1024x1024 pixel images, varying parameters such as sliding window size, scaling factor, and number of classifiers. A novel method for locating key areas in medical images using Haar-like and contour features is proposed and evaluated on a dataset of MRI images. The results demonstrate superior performance compared to reference techniques, maintaining over 90% accuracy in locating key areas even with a database of 200 images. This high accuracy is attributed to expanded Haar-like feature templates, efficient computation using integral images, and a comprehensive contour feature extraction process. The paper concludes that the proposed method shows promise for enhancing medical image analysis and computer-aided diagnosis.

This article presents information on the location, methods and methods of research, the effect of phosphorus fertilizers on the formation of the leaf area of winter wheat. According to this, information was provided on that before planting winter wheat seeds, using ammophos fertilizer 90 kg/ha, potash fertilizer 60 kg/ha, nitrogen fertilizer 200 kg/ha during the growing season, and apply PS-agro pure under the plow at the end of the growing season and nitrophos (NKFU) fertilizers 90 kg/ha, potassium fertilizer 60 kg/ha, compared to the options that used nitrogen fertilizer at the rate of 200 kg/ha during the growing season, the leaf area was up to 2589,7–5341,2 m2/ha, biological dry mass accumulation was up to 9,4–16,2 c/ha.

The synthesis of special photocatalysts of nanostructured functional ceramics (PNFC) under the ZKHM brand under the influence of concentrated solar radiation showed the effectiveness of these ceramic materials in multifunctional use, in particular as additives for coatings of welding electrodes. However, problems with producing these materials in solar ovens on an industrial scale did not allow the widespread use of this method. This problem was solved using the technique of PNFC synthesis, followed by activation by pulsed radiation generated by functional ceramics. The ceramic material obtained by this method under the brand name ZB-1 also showed its effectiveness when used as an additive in welding electrode coatings. A comparative analysis of the effectiveness of the actions of additives from the ZKHM and ZB-1 brands on the welding and technological properties of welding electrodes from the MR-3 brand was carried out. Comparative results for the formation of weld beads showed that beads with high-quality formation without external defects were achieved when surfaced with electrodes with additives from both brands at concentrations up to 1%. Also, at concentrations up to 1%, these additives increased the breaking length of the arc and the stability of arc welding. The different effects of these additives were observed in a comparative analysis of their impacts on the size of the visor at the end of the electrode, the coefficients of melting and surfacing, and the loss factor for fumes and splashing of electrode metal.

Many issues related to the use of land resources have been considered in the context of the possible application of modern information systems to improve the efficiency of agricultural management and ensure food security. The article aims at facilitating the introduction of information systems into the management of land resources in the Republic of Kazakhstan and improving the efficiency of managing its agricultural territories. Based on the analysis of documents and the results of an expert survey, the authors determine the implementation of land management information systems, its main stages and reasons for failures which require solutions through joint efforts of both the state and business. It is concluded that the information support for land management gives a comprehensive idea about the organization of land resources in a particular area, streamlines agricultural land and crop rotations, and helps make informed decisions in the process of land management, provides an opportunity for each participant in the agricultural market of Kazakhstan to quickly obtain accurate, reliable and sufficient information at minimum cost. The obtained results will to understand Kazakhstan's experience in the field of land resource management and apply it to the development of national management information systems.

Birds inhabiting urban areas in the process of urbanization acquire a variety of adaptations to new habitat conditions. Sports facilities, areas for mass recreation and physical culture of citizens have become a characteristic mandatory component of urban development. Trophic connections and numerous behavioral reactions, specifically related to the specifics and nature of the use of physical culture objects, have been revealed.

Introduction. The urgency of the issues evaluating the effectiveness of various laser surgery techniques in patients with benign prostatic hyperplasia (BPH) is determined by the presence of a significant number of various complications.Objective. To conduct a comparative analysis of the efficacy and safety of two methods of diode laser surgery for benign prostate hyperplasia.Materials & methods. Retrospective study by monitoring and analysing histories included 52 patients with BPH to compare the efficacy and safety of two techniques of diode laser surgery of BPH. The surgical intervention (prostate enucleation — DiLep or vaporization — DiVap) was performed using diode laser with power of 150 W and wavelength of 980 nm ("MILON" Ent., St. Petersburg, Russian Federation). The efficacy of laser technologies was evaluated according to the following criteria: surgery time (min), prostate volume (cx), post-void residual urine volume (ml), severity of LUTS and quality of life related to urination according to the IPSS-QoL scale (points).Results. The DiLep time for prostate volume 71.3 ± 20.2 cc was 62 - 95 min (71.3 ± 12.6 min), whereas for prostate volume 70.4 ± 21.3 cc the DiVap duration was 50 – 67 min (59.8 ± 8.6 min) with a significant difference between the groups (p = 0.0001). The mean length of hospital stay for patients in the DiLep group was 3.4 ± 1.2 bed-days, whereas in the DiVap patient group it was significantly shorter and averaged 2.2 ± 1.1 bed-days (p = 0.008).Conclusion. Diode laser vaporization (DiVap) requires significantly less surgery time and length of hospital stay than hyperplasia enucleation (DiLep).

Background: Radiochemical purity is a key criterion for the quality of radiopharmaceuticals used in clinical practice. The joint improvement of analytical methods capable of identifying related radiochemical impurities and determining the actual radiochemical purity, as well as the improvement of synthesis methods to minimize the formation of possible radiochemical impurities, is integral to the implementation of high-tech nuclear medicine procedures. PSMA-targeted radionuclide therapy with lutetium-177 has emerged as an effective treatment option for prostate cancer, and [177Lu]Lu-PSMA-617 and [177Lu]Lu-PSMAI&T have achieved global recognition as viable radiopharmaceuticals. Recently, it was shown that specific radiochemical impurities can form during the synthesis of [177Lu]Lu-PSMA-617 because of a spontaneous, thermally mediated condensation of the Glu-C(O)-Lys fragment, resulting in the formation of three different cyclic forms (with no affinity for PSMA). During this study, we identified another impurity, a product of detachment of the Glu-CO fragment from PSMA-617, caused by heating. The total content of all four thermally mediated degradation products may reach 9–11% during classical incubation for 30 min at 95 °C, reducing the radiochemical purity to an unacceptable level (albeit with high levels of radiochemical conversion). It is reasonable to assume that the formation of similar impurities is characteristic of all PSMA-specific vectors that contain Glu-C(O)-Lys pharmacophores. Because the formation of these impurities directly depends on the temperature and incubation time, to reduce their content in the reaction mixture at the end of the synthesis, it is necessary to select conditions to achieve a high level of radiochemical conversion for the minimum possible time and/or at the minimum sufficient temperature. Methods: In this study, using [177Lu]Lu-PSMA-617 as an example, we evaluated the efficiency of alternative methods of synthesis with microwave heating and co-solvent (ethanol) addition to ensure radiochemical yield and radiochemical purity in the shortest possible time and at the minimum necessary and sufficient synthesis temperature. Results: Both approaches achieved a significant reduction in the impurities content, while achieving satisfactory synthesis yields in a short time. In addition to improving the synthesis parameters and radiochemical purity, the use of microwave heating and the addition of ethanol reduces the negative influence of other auxiliaries on labeling kinetics. Notably, the addition of ethanol under certain conditions allowed [177Lu]Lu-PSMA-617 to be synthesized at room temperature for only 10 min. This makes it possible to achieve exceptionally high real radiochemical purity of the preparations, determined only by the quality of the original precursor. The approaches considered in this study can be successfully applied to improve the synthesis process and quality parameters of the finished product, both for known radiopharmaceuticals and for those under development.

We consider the Cauchy problem for a one-dimensional homogeneous system of poroelasticity equations described by three elastic parameters in a reversible hydrodynamic approximation. We find a solution to the Cauchy problem in the form of the d'Alembert formula and show the influence of porosity on the acoustic wave propagation. Bibliography: 5 titles., 1 Introduction For applied problems of the theory of elastic wave propagation it is often required to take into account the medium porosity, fluid saturation of the medium, and the [...]

Author(s): Arman Rakhimov [sup.1] , Jason Ong [sup.2] , Anu Realo [sup.1] [sup.3] , Nicole K. Y. Tang [sup.1] Author Affiliations: (1) grid.7372.1, 0000 0000 8809 1613, Department of Psychology, [...], The study examined the relationship between self-compassion and sleep quality. We also investigated whether the relationship was mediated by brooding, perceived stress, sleep hygiene, and anxiety about sleep and whether self-compassion was associated with anxiety, depression, and mental well-being indirectly through sleep quality. A sample of 468 adults completed measures of demographics, health, sleep quality, self-compassion, predisposing (arousability, brooding, perfectionism, interpersonal problems), precipitating (perceived stress, presence of life-changing events) and perpetuating (sleep hygiene, anxiety about sleep) factors of insomnia, depression, anxiety and mental well-being. The results of the hierarchical multiple regression analysis revealed that low self-compassion was significantly associated with poorer sleep quality when controlling for socio-demographic variables, health-related factors and predisposing factors of insomnia. The association, however, became non-significant when precipitating and perpetuating factors of insomnia were added to the model. Structural equation modelling showed that the relationship between self-compassion and sleep quality was mediated by anxiety about sleep and through sequential mediations involving anxiety about sleep and then sleep hygiene; or anxiety about sleep, perceived stress and then sleep hygiene; or perceived stress and then sleep hygiene. Poor sleep in turn was associated with anxiety and depression, which had a negative effect on mental well-being. This study provided cross-sectional evidence that low self-compassion is a potential risk factor for poor sleep quality, and consequently, poor mental well-being. These findings provide insights into possible mechanisms underlying the relationship between self-compassion and sleep quality that could inform etiological models of insomnia.

In this work, the influence of two-dimensional state density on oscillations of transverse electrical conductivity in heterostructures with rectangular quantum wells is investigated. A new analytical expression is derived for calculating the temperature dependence of the transverse electrical conductivity oscillation and the magnetoresistance of a quantum well. For the first time, a mechanism has been developed for oscillating the transverse electrical conductivity and magnetoresistance of a quantum well from the first-order derivative of the magnetic field (differential) at low temperatures and weak magnetic fields. The oscillations of electrical conductivity and magnetoresistance of a narrow-band quantum well with a non-parabolic dispersion law are investigated. The proposed theory investigated the results of experiments of a narrow-band quantum well (InxGa1-xSb).