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The article examines the state of the organization of state control at the present stage of economic development in the field of ensuring labor and equipment safety. An analysis of inspections in this area showed a decrease in their number by federal inspections in order to reduce the burden on business. When studying the regulatory framework of the Russian Federation on labor and equipment safety, as well as examining statistical data regarding the state of labor protection and equipment safety in the Russian Federation, a conclusion was made about the lack of control in this area. In this regard, the organizational development of public control is proposed.

Consideration is being given to the geochemical composition of the rocks, representing the hidden part of the volcanic and intrusive material in the structure of the Yenisei-Khatanga Trough (YKT), in relation to its belonging to a large igneous province (LIP) of Siberia. The geochemical characteristics of mafic rocks, presenting in the sedimentary complexes of the YKT, correspond to three types of mafic rocks allocated to the Siberian LIP: Nadezhdinsky (low Ti), Morongovsky (low Ti), and, in limited quantities, Ivakinsky (rift-related high Ti). Based on the seismic data, there was constructed a deep structural-tectonic cross-sectional model, and there was considered the position of mafic intrusions in the sedimentary section in the western junction zone of the Siberian Platform and the Kara (Taimyr-Severozemelsky) orogen. The seismic data show an anomalous area in the lower crust and at the crust–mantle boundary immediately below the YKT depocenter, whose seismic section is characterized by a chaotic scattered wave field with no reflective boundaries.

The bumble bee fauna of the Russian Arctic is rather poorly known. Kolguev Island, a remote insular territory in the Barents Sea, is one of the deficiently studied areas. In this study, material on Kolguev’s bumble bees is re-examined, phylogeographic data analysed, putative scenarios explaining the origin of the bumble bee fauna on the island discussed, and the biology and phenology of these insular populations described. Five bumble bee species, i.e., Bombus flavidus, B. lapponicus, B. jonellus, B. pyrrhopygus, and B. balteatus, were recorded on this island. All of these species are widespread throughout the Eurasian Arctic. Bumble bee populations on Kolguev Island are characterised by a low level of molecular divergence from mainland populations. Based on paleogeographic reconstructions and phylogeographic patterns, it is hypothesised that the bumble bees appeared on this island in the Early Holocene. The lack of rodents (lemmings and voles) sharply decreases the number of available nesting places for bumble bees on Kolguev Island.

The paper presents the results of studies of composite materials based on epoxy resins with different types of filling are considered. It is shown that a material with a metal filler has higher mechanical characteristics compared to a material filled with ceramics. The material retains high mechanical properties at low temperatures and after interaction with petroleum products. Hydraulic tests showed that the material with a ceramic filler withstood only on non-through defects. The metal-filled material has passed the tests for non-through defects and through defects at pressures up to 4,0 MPa. The material with a filler based on Fe and Cr powder can be used in pipeline construction for temporary repair of valves with non-through defects or through defects of valves operating up to 1,6 MPa.

Gliomas are the most common primary tumors of the central nervous system. Their aggressive form – glioblastomas is characterized by an unfavorable prognosis and a high frequency of relapses. It is believed that prior traumatic brain injury is one of the possible factors for the subsequent development of glial brain tumors. Several authors have proposed several criteria for establishing a possible causal relationship between traumatic brain injury and gliomas. However, the actual role of antecedent brain injury in the pathogenesis of this tumor type is still a matter of debate. It has been suggested that traumatic injuries cause an active and prolonged inflammatory process, while disrupting the permeability of the blood-brain barrier, which leads to exposure of the brain tissue to carcinogenic (toxic) substances, various growth factors or cells of the immune system circulating in the bloodstream, which ultimately can lead to malignant transformation of glial cells. One of the evidence for this hypothesis is supported by reports of meningiomas located adjacent to posttraumatic meninges and cerebral scars. In this paper, we will try to elucidate the potential relationship between traumatic brain injury and the formation of glial brain tumors.

When mining hard coal the underground method is prevailed. This method provides a higher quality of the mineral. Methane emissions occur in coal mines during the development of gasbearing seams. These emissions are the reason for the formation of an explosive mixture when mixed with mine air, and also contribute to the spontaneous combustion of coal. Methane alarms are used to monitor the mine atmosphere. Thermocatalytic sensor is the main element of such a gas analyzer. The sensor is placed in a breathable housing. This body is called a flame arrester. This article discusses the possibility of replacing the material used for the manufacture of a flame arrester. The basis of the existing material is nickel powder. It is proposed to replace it with a cermet bond. The composition of the ceramic material of the part is developed by the author and presented in the article. Replacement of material will lead to a significant reduction in the cost of the part and simplification of the manufacturing technology.

The influence of modification of heat-resistant nickel-based alloys on the crystallization kinetics of alloys was established by the methods of thermal analysis. This effect is expressed in the increase in solidus temperature and, as a consequence, narrowing the crystallization range of the alloy, the increase in the growth rate of a solid solution, and change in the temperature of precipitation of eutectic and strengthening phases. As a result, the use of modification with refractory particles makes it possible to exert an additional effect on the structure and properties of nickel-based alloys without additional heat treatment.

Аs a result of the study, a three-dimensional finite element model of a wheelset with rail sections is developed using a finite element of the ten-node tetrahedron type, and the maximum tangent stresses and maximum equivalent stresses are determined according to the theory of Mises and Dang Wang. It is shown that the maximum shear stresses are observed at a point located at a depth of 4,5–5,3 mm below the surface of the wheel. In case of emergency (short) braking, the maximum stresses take place on the surface of the wheel. With prolonged braking (the movement of the train on a long descent), maximum stresses occur at the point of transition from the disk to the rim on the inside of the wheel, and the value of these stresses is 2,5 times higher than in emergency braking mode. The finite element method is used to determine the stress-strain state of the wheelset of a freight car during braking.

The High Arctic bumble bee fauna is rather poorly known, while a growing body of recent molecular research indicates that several Arctic species may represent endemic lineages with restricted ranges. Such local endemics are in need of special conservation efforts because of the increasing anthropogenic pressure and climate changes. Here, we re-examine the taxonomic and biogeographic affinities of bumble bees from Novaya Zemlya using historical samples and recently collected materials (1895–1925 vs. 2015–2017). Three bumble bee species inhabit the Yuzhny (Southern) Island and the southern edge of Severny (Northern) Island of this archipelago: Bombus glacialis Friese, 1902, B. hyperboreus Schönherr, 1809, and B. pyrrhopygus Friese, 1902. Bombus glacialis shares three unique COI haplotypes that may indicate its long-term (pre-glacial) persistence on Novaya Zemlya. In contrast, Bombus hyperboreus and B. pyrrhopygus share a rather low molecular divergence from mainland populations, with the same or closely related haplotypes as those from Arctic Siberia and Norway. A brief re-description of Bombus pyrrhopygus based on the newly collected topotypes is presented. Habitats, foraging plants and life cycles of bumble bees on Novaya Zemlya are characterized, and possible causes of extremely low bumble bee abundance on the archipelago are discussed. The species-poor bumble bee fauna of Novaya Zemlya is compared with those in other areas throughout the Arctic. The mean bumble bee species richness on the Arctic Ocean islands is three times lower than that in the mainland Arctic areas (3.1 vs. 8.6 species per local fauna, respectively). General linear models (GLMs) indicate that this difference can be explained by specific environmental conditions of insular areas. Our findings highlight that the insularity is a significant factor sharply decreasing species richness in bumble bee assemblages on the Arctic Ocean archipelagoes through colder climate (lower summer temperatures), prevalence of harsh Arctic tundra landscapes with poor foraging resources, and in isolation from the mainland.

The article presents the results of work on the study of the use of a single-phase rectifier with an additional unit for obtaining pulsed modes for manual arc welding with thin-walled construction by a stick electrode. The proposed scheme of an additional block allows by selecting the parameters of the welding mode to ensure a stable quasistationary process of melting and transfer of the electrode metal. Thus, it becomes possible to weld thin-sheet structures without reducing the diameter of the coated electrode.