Abstract—An EIGEN-6C4 model for the Altai-Sayan region and northwestern Mongolia constructed using data from satellite gravimetric missions and the results of ground-based measurements with absolute gravimeters and space geodesy receivers is considered. Using the EIGEN-6C4 geopotential (ETOPO1 relief), within the framework of a homogeneous crust model with the involvement of seismic exploration data on the platform part of the study area, an idea was obtained about the changes in the thickness of the earth’s crust in central Asia for the territory extending from 56° to 46° north latitude and from 80° to 100° east longitude, covering Gorny Altai, Kuznetsk Alatau, Western Sayan and Eastern Sayan, Tuva Basin, Tarbagatai Ridge (Kazakhstan), Mongolian Altai (PRC, Mongolia), Great Lakes Basin and Khangai Ridge (Mongolia). Research has shown that the depth of the Mohorovičić boundary increases from the northwest to the southeast of the territory from 40 to 55 km. For the mountainous regions in the south (Mongolian Altai, Khangai Range), the maximum crustal thickness was 55 km. For intermountain valleys and depressions (Tuva Basin, Big Lakes Basin) the depth of the Moho surface is within 45–47 km. In the north, in the flat part of the territory, the thickness of the crust is from 40 to 43 km. The differences between models constructed using gravimetric and seismic data are considered.
Markers of α2- and β1-adrenergic receptors (AR) were detected immunohistochemically in the liver of db/db mice with obesity and type 2 diabetes mellitus before and after melatonin treatment. Melatonin (1 mg/kg in 200 μl distilled water) was administered intragastrically from the 8th to the 16th week of life. The comparison groups were intact and placebo-treated db/db mice. Melatonin administration resulted in a significant increase in the relative areas of β1- and α2-AR expression, with a tendency towards an increase in the area ratio, as well as a significant increase in the ratio of β1/α2-AR concentrations due to preferential increase in β1-AR parameters. Melatonin administration apparently reduces sympathetic neuropathy of the liver and promotes the shift of lipid metabolism processes in hepatocytes towards lipolysis activation, which allows us to consider this hormone as a promising component of complex therapy of fatty liver disease.
Monitoring of the stability of technogenic objects is a critical aspect of ensuring safety and preventing emergencies caused by mining and geological processes. The integrated use of various monitoring methods allows obtaining comprehensive information on the dynamics of deformation processes. The complex system of geotechnical monitoring of technogenic objects on the basis of geospatial data was developed, which was tested in the conditions of the "Edelweiss +" open-pit coal mine (Republic of Kazakhstan). The system was based on the step-by-step integration of Earth remote sensing methods, satellite radar interferometry, aerial photography with the use of unmanned aerial vehicles (UAV), as well as modern instrumental methods - electronic tacheometry and GNSS measurements. The first stage - analysis of archive satellite images to identify areas of significant surface displacements. The second stage is aerial photography using UAV to create detailed 3D models of surface areas with deformations. The third stage includes the creation of a geomechanical monitoring system based on instrumental observation methods in areas with critical changes. The final stage is the creation and updating of a geospatial database that provides continuous monitoring of the object's condition. As a result of testing of the geotechnical monitoring system based on Sentinel-1 and TerraSAR-X/TanDEM-X satellite images, surface subsidence of up to 25 mm was detected on the northern side of the "Edelweiss +" open-pit mine. Aerial photography of the open-pit mine allowed us to construct digital 3D models of the terrain, the comparison of which confirmed deformation processes at the +556 m horizon. Instrumental observations using modern geodetic methods clarified the type and dynamics of deformations of the rock mass. Integration of geospatial data in the geotechnical monitoring system ensures prompt detection of deformations, their analysis and forecast, which allows us to minimize the risks of destruction and increase the safety of operation of technogenic objects.
Measurements of the gravitational frequency shift of a hydrogen clock were carried out when it was moved between two points located at different orthometric heights when transmitting the signal simultaneously via radio cable and optical fiber. Based on the obtained values of the average relative difference frequency, that of orthometric heights was calculated depending on the positions of the transported quantum clocks, the average value of which is 43,08 m. The maximum error based on the outcome of four height determinations is 2,58 m and it is 6,3 % of the actual value of 41,26 m. From the analysis of the obtained results, it follows that the main factor affecting the accuracy of altitude definition by the chronometric leveling method is the systematic change in the frequency of the transported quantum clocks. The main contribution to the error budget is made by the RMSD of the transported quantum clocks, which is 1,73 ⸱ 10^(–15)
This study investigates the modeling of the vertical gravity gradient (VGG) in the Republic of Kazakhstan using three non-instrumental methods: global geopotential models (GGMs), a precomputed VGG grid from the Institute of Geophysics and Planetary Physics (IGPP), and a method combining the normal gravity field with digital elevation models (DEMs). The research compares these modeled VGG values with high-precision measurements from 48 outdoor gravity stations, employing Scintrex CG-6 gravimeters for indirect VGG determination. Key findings reveal that topographic modeling is unreliable for stations located in depressions due to unaccounted mass above benchmarks. At the same time, GGMs provide results comparable to the normal gradient but lack resolution for stations on elevated terrain. After excluding problematic stations, modeling accuracy improved to approximately 10 μGal/m. The study concludes that while direct VGG measurements remain essential near the Earth's surface, modeled values can offer better accuracy than theoretical corrections in specific scenarios, depending on the detail of input data. The research highlights the importance of VGG in geodesy and gravimetry, particularly for high-precision applications. It underscores the limitations of current modeling techniques in accounting for local topographic and subsurface density variations. The work contributes to refining methods of gravity data reduction and supports the development of Kazakhstan's geodetic infrastructure.
