Abstract
Photooxidative transformations and mechanisms of oxidative reactions in aromatic groups of hydrocarbons isolated from heavy Surakhan (Azerbaijan) petroleum under atmospheric conditions have ...been investigated. Polycyclic aromatic hydrocarbons, which are part of the aromatic components of heavy Surakhan petroleum, after irradiation with UV rays for 1÷11 hours in the presence of oxygen undergo chemical transformations: endoperoxides polycyclic aromatic hydrocarbons, quinones, etc. are formed. It was found that oxidation products under atmospheric conditions can be formed as follows: during the oxidation of acenes (naphthalene, anthracene), which are part of the aromatic groups of petroleum components, excited aromatic hydrocarbons (donor) interact with atmospheric oxygen (acceptor) in the triplet state with the transition of the acceptor to excited state with the formation of singlet oxygen
1
O
2
, in this case the donor molecule returns to the ground state. When phenanthrene is photooxidized, quinones are formed (the reaction is irreversible).
Abstract
This article focuses on the study of physical and geographical aspects of toponymy, which involves the naming and renaming of geographical objects based on the natural features of a place. ...The research in this field prioritizes the normalization and standardization of geographical names, compilation of a state register of geographical names, proper use of names, publication of toponymic dictionaries, and transliteration of geographical names. In this regard, the present paper analyzes scientific research on toponyms from various regions worldwide, including Uzbekistan. A classification system of geographical names and physical and geographical features of toponyms specific to the regions of Uzbekistan has been developed and recommended, taking into account the natural characteristics of the place. Additionally, thematic toponymic maps have been developed.
Introduction.
Modern gynecological endocrinology widely discusses various disorders accompanying the onset of menopause. Metabolic disorders are one of the leading risk factors for the development of ...ischemic heart disease and vascular dystonia in menopausal women. That is why the drugs prescribed as part of menopausal hormone therapy are contraindicated for patients with severe metabolic disorders and predisposition to thrombosis. Women with a normal body mass index may develop the menopausal metabolic syndrome, since its presentations largely depend on the total body composition and the specific gravity of visceral adipose tissue.
Aim.
To assess the patterns of clinical presentation of menopause in women with metabolic menopausal syndrome.
Materials and methods.
In the furtherance of that aim, we examined 184 women who were in menopause 1 to 5 years at the age of 52 to 57 years (average age 54.2 ± 0.5 years). Of these, 87 were diagnosed with metabolic syndrome – they were included in the main group. The comparison group included 97 menopausal women without metabolic disorders.
Results and discussion.
We assessed the severity of clinical presentations and the total body composition of the patients in the selected groups. It has been established that the body mass index cannot serve as a criterion for evaluation of metabolic processes, despite the sufficient simplicity of its computation.
Conclusions.
The authentic view of the risks of metabolic disorders in menopausal women requires the study of total body composition.
One of the most frequent clinical and laboratory manifestations and complications of inflammatory bowel diseases (IBD) is anemia. In the presented review the reasons, criteria of diagnostics and ...therapeutic correction of various variants of anemia in Crohn’s disease are considered.
Age-related macular degeneration (AMD) is one of the main causes of loss of sight and hypovision in people over working age. Results of optical coherence tomography (OCT) are essential for ...diagnostics of the disease. Developing the recommendation system to analyze OCT images will reduce the time to process visual data and decrease the probability of errors while working as a doctor. The purpose of the study was to develop an algorithm of segmentation to analyze the results of macular OCT in patients with AMD. It allows to provide a correct prediction of an AMD stage based on the form of discovered pathologies. A program has been developed in the Python programming language using the Pytorch and TensorFlow libraries. Its quality was estimated using OCT macular images of 51 patients with early, intermediate, late AMD. A segmentation algorithm of OCT images was developed based on convolutional neural network. UNet network was selected as architecture of high-accuracy neural net. The neural net is trained on macular OCT images of 125 patients (197 eyes). The author algorithm displayed 98.1% of properly segmented areas on OCT images, which are the most essential for diagnostics and determination of an AMD stage. Weighted sensitivity and specificity of AMD stage classifier amounted to 83.8% and 84.9% respectively. The developed algorithm is promising as a recommendation system that implements the AMD classification based on data that promote taking decisions regarding the treatment strategy.
MCM-41 type mesoporous silica particles were obtained using a template method in an alkaline medium and cetyltrimethylammonium bromide as a matrix. The structural and adsorption characteristics of ...the mesoporous material were studied by dynamic light scattering, scanning electron microscopy, low-temperature adsorption—desorption of nitrogen, IR spectroscopy, and simultaneous thermal analysis. It was shown that the obtained mesoporous material possesses high porosity with the specific pore volume in excess of 1 cm
3
g
−1
. It was established that the size of silica particles does not exceed 200 nm, which is a value acceptable for the penetration of drugs through cell membranes. The optimal compositions of aqueous dispersions of MCM-41 with minimal sedimentation processes were determined. A drug (indomethacin) was encapsulated into the silica pores using the precipitation method at various temperatures (40 and 60 °C), the quantitative parameters of loading efficiency were calculated. The infl uence of temperature on the encapsulation ability was demonstrated.
RELEVANCE . The challenges of creating modern permanent magnet synchronous motors require solving technical problems in conjunction with economic realities. Due to the use of permanent magnets in the ...construction of synchronous motors, their cost limits their industrial application. Therefore, there is an urgent issue of optimizing the design of synchronous motors, which can be solved by changing the topology. TARGET . The goal is to create more economical permanent magnet synchronous motors (PMSMs) in low-power electric vehicles. It is planned to implement a new method for constructing PMSM. This solution will reduce weight and size parameters and increase specific power, which are important indicators for electric transport. METHODS . To modernize modern synchronous motors, a complex topological optimization method based on a genetic algorithm is proposed. RESULTS . A computer model was obtained in the form of calculation of electromagnetic fields in the stator and rotor of a synchronous motor with permanent magnets. CONCLUSION . Modeling the parameters of synchronous motors with permanent magnets has a low degree of development in the domestic mechanical engineering due to the lack of developed infrastructure in the field of low-power electric transport; the creation of domestic developments in this area is of a strategic nature.
Aim
. The aim of the study is to analyse the problem of heat dissipation in high-power transistors and develop devices for their thermal stabilisation when used in electronic equipment.
Method.
A ...method is proposed for testing power transistors using a device to to ensure thermal stabilisation in the stating volume by means of a two-position temperature controller along with a model for the use of these components in electronic devices. The proposed devices support high thermal stabilisation accuracy of power transistors in a radioelectronic device system allowing temperature to be maintained at a given level with high accuracy by means of a thermoelectric battery.
Results
. Device designs were developed for increasing the accuracy of thermal stabilisation of power transistors with high efficiency, low energy consumption and small size.
Conclusion.
Based on the results of experimental studies, optimal designs for devices for the thermostabilisation of radioelectronic device components that dissipate significant power during their operation are presented. The devices can be used to increase the accuracy of thermal stabilisation of the radioelectronic device element by means of a working substance whose melting point coincides with its thermal stabilisation temperature. The developed devices have the following functions: the thermoelectric battery sections of the thermoelectric battery will be sequentially disconnected depending on the electrical signals from the temperature sensors to which the solid phase of the working substance has moved. The battery of the thermoelectric module (TEM) removes excess heat from the heat-stabilising substance while maintaining the required temperature of the radioelectronic device element. Excess heat from the heat-generating junctions of the TEM battery is removed by the heat exchanger. During melting of the working substance, the temperature of the thin-walled metal container – and, accordingly, the temperature of the CEA element – can be maintained at a constant value equal to the melting temperature of the working substance.
Introduction.
Cervical cancer holds one of the top positions in the oncological diseases ranking among the female population in the presence of iodine deficiency in the territory of the Republic of ...Bashkortostan. It's commonly believed that it is caused by the development of cervical intraepithelial neoplasia (CIN) associated with highly oncogenic strains of the human papillomavirus (HPV). The article pays special attention to the risk factors for the development of precancerous and cancerous diseases of the cervix and their timely treatment.
The aim of the study
was to improve the diagnosis and therapy of HPV-associated CIN in the presence of iodine deficiency in the Republic of Bashkortostan.
Materials and methods.
256 women aged between 21 and 45 years with identified HPV-associated CIN I were enrolled in our study. The first stage of treatment known as preoperative was carried out in the outpatient setting. At stage 2, the patients were offered a radio-wave surgery treatment of the cervix.
Results and discussion.
The video colposcope analysis showed that the average time of epithelialization of the cervix after exposure to the destruction depended on the age and duration of the disease. For instance, complete epithelialization of the cervix in the group of patients aged between 21 to 38 years was reported in 72% of cases by Day 40, and in 62% of cases in the group of 39-45 years old on Day 40. The complete elimination of the virus was observed in 236 patients out of 256 cases (92%) 70 days after the end of therapy.
Сonclusion.
The study proves the effectiveness of the combination treatment of patients with HPV-associated CIN.
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