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The adhesion of polyurethane thermal insulation to a waterproof outer casing of polyethylene in the construction of preinsulated bonded pipe systems used as a building material for directly buried hot water networks is investigated. In order to extend the life of pipes for hot water networks from standard 30 years to 50 years or more, it is proposed to use polyurea as a waterproof coating. It is proposed to determine the adhesion strength of thermal insulation with a waterproof outer casing for shear in the tangential direction at the edge "Waterproof outer casing of polyethylene - Polyurethane thermal insulation". Test results are presented. The results of calculations of the heat losses of the preinsulated pipe construction are presented. The testing results of the behaviour of polyurea coating in the ground are presented. Conclusions are drawn about the possibility of using polyurea as a waterproof coating for preinsulated bonded pipe systems for directly buried hot water networks.

This study addresses the cervical part of the vertebral column. Clinical pictures of dystrophic diseases of the cervical part of the vertebral column do not always correspond only to the morphological changes-they may be represented by connective tissue formation and nerve and vessel compression. To find out the possible reason, this morphometric study of the cervical part of the vertebral column in 40 cadavers was performed. CT scans were performed on 17 cadaveric material specimens. A total of 12 histological samples of connective tissue structures located in intervertebral canals (IC) were studied. One such formation, an intracanal ligament (IL) located in the IC, was found. Today, there is no term "intervertebral canal", nor is there a detailed description of the intervertebral canal in the cervical part of the vertebral column. Cervical intervertebral canals make up five pairs in segments C2-C7. On cadavers, the IC lateral and medial apertures were 0.9-1.5 cm and 0.5-0.9 cm, correspondingly. According to our histological study, the connective tissue structures in the IC are ligaments-IL. According to the presence of these ligaments, ICs were classified into three types. Complete regional anatomy characterization of the IC of the cervical part of the vertebral column with a description of its constituent anatomical elements was provided. The findings demonstrate the need to include the terms "intervertebral canal" and "intervertebral ligament" in the Terminologia anatomica .

Purpose: There is no systematic description of primary anatomical landmarks that allow a surgeon to reliably and safely navigate the superior and posterior mediastinum's fat tissue spaces near large vessels and nerves during video-assisted endothoracoscopic interventions in the prone position of a patient. Our aim was to develop an algorithm of sequential visual navigation during thoracoscopic extirpation of the esophagus and determine the most permanent topographic and anatomical landmarks allowing safe thoracoscopic dissection of the esophagus in the prone position., Methods: The anatomical study of the mediastinal structural features was carried out on 30 human cadavers before and after opening the right pleural cavity., Results: For thoracoscopic extirpation of the esophagus in the prone position, anatomical landmarks are defined, their variants are assessed, and an algorithm for their selection is developed, allowing their direct visualization before and after opening the mediastinal pleura., Conclusion: The proposed algorithm for topographic and anatomical navigation based on the key anatomical landmarks in the posterior mediastinum provides safe performance of the video-assisted thoracoscopic extirpation of the esophagus in the prone position., (© 2021. The Author(s).)

The research aims were to find out further intraosseous mandible organization indications and to structure it systematically., Material and Methods: in our research 400 mandibles were used: for the intraosseous examinations in total 300 mandibles of persons aged 20-65 were used. For all corpses cephalic index was measured. Segmentation of the mandibles were made by Jigley saw between medial root of the first molar at one side and central and second incisor of the opposite one. After that segments were stained with Schiff's reagent with following preparation. Dry preparations (n = 100) were used in exploration of mental foramen macroanatomy., Results: mental foramen cavity depth was divided into three types: low, n = 33 (depth 269 ± 081 mm), medium, n = 36 (depth 358 ± 092 mm) and deep, n = 31 (depth 417 ± 036 mm); transverse size of the cavity is 3109 ± 041 mm and longitudinal size is 397 ± 055 mm. According to the mandible anterior intraosseous organization research it is possible to make a mental nerve intraosseous canal types systematization: semi-oval; straight; s-shaped type, formed by two opposite and transient bends. The S-shaped type (49%) is more common in persons with a dolichocephalic skull type, especially (57.55%) in mesocephalic type and semi-oval (66.36%) in brachycephalic type., Conclusion: nerve in the eponymous mental foramen, (which we would like to call a cavity), is branched into two large branches: the extraosseous branch, which innervates the soft tissues (such as Rr. mentales, Rr. labiales and Rr. gingivales), and the intraosseous branch, which runs from the mental foramen to the symphysis, from the latter branch to the first premolar, to the canine and to the incisors., (Copyright © 2020 Elsevier GmbH. All rights reserved.)

Objective: To evaluate the status of individual hemodynamic parameters (HR) and respiratory indicators of dentists performing local anesthesia. Material and methods. In the period from April 2019 to December 2019 the determination of heart rate (Heart rate) and blood saturation at 120 doctors aged 25-55 years was performed. The value of blood saturation by non-invasive pulse oximeter technique: SpO 2 measurement range 0-99%; heart rate range 18-300 beats per minute. The limit of 95-98% was considered normal. However, we consider it correct to note the introduction of an error of 0.1% due to the constant wearing of a dentist's tight polymer mask. All subjects were preliminarily determined by Robergs-Landvere formula: maximum heart rate (MF)=205.8-(0.685·age)., Results: Maximum HR limits for the groups of subjects were 185.6±3.1 beats per minute in the first group; 178.7±3.1 beats per minute in the second group; 171.5±3.4 beats per minute in the third group. In all groups the tendency to decrease blood saturation in case of pain appearance in patients during treatment against the background of block anesthesia, as well as during anesthesia on the mandible was determined. The definition of SpO 2 showed a slight downward trend in blood saturation when pain occurs within normal parameters. Thus, the limit of changes in the index against the background of performed local anesthesia on the mandible was 95.2-96.1% and 96.3-96.6% on the maxilla., Conclusion: Measurement of arterial oxygen saturation in dentists showed a tendency for a slight decrease in this indicator within the normal range when the patient developed pain. Thus, the limit of changes in the indicator against the background of local anesthesia on the lower jaw was 95.2-96.1%, on the upper jaw - 96.3-96.6%.