National Report for the IAG of the IUGG 2019-2022

Major results of researches conducted by Russian geodesists in 2019-2022 on the topics of the International Association of Geodesy (IAG) of the International Union of Geodesy and Geophysics (IUGG) are presented in this issue. This report is prepared by the Section of Geodesy of the National Geophysical Committee of Russia. In the report prepared for the XXVII General Assembly of IUGG (Germany, Berlin, 11-20 July 2023), the results of principal researches in geodesy, geodynamics, gravimetry, in the studies of geodetic reference frame creation and development, Earth's shape and gravity field, Earth's rotation, geodetic theory, its application and some other directions are briefly described. For some objective reasons not all results obtained by Russian scientists on the field of geodesy are included in the report.Comment: Misprint in the title of the arXiv record has been corrected. The submission content is not affecte

The scattering from generalized Cantor fractals

We consider a fractal with a variable fractal dimension, which is a generalization of the well known triadic Cantor set. In contrast with the usual Cantor set, the fractal dimension is controlled using a scaling factor, and can vary from zero to one in one dimension and from zero to three in three dimensions. The intensity profile of small-angle scattering from the generalized Cantor fractal in three dimensions is calculated. The system is generated by a set of iterative rules, each iteration corresponding to a certain fractal generation. Small-angle scattering is considered from monodispersive sets, which are randomly oriented and placed. The scattering intensities represent minima and maxima superimposed on a power law decay, with the exponent equal to the fractal dimension of the scatterer, but the minima and maxima are damped with increasing polydispersity of the fractal sets. It is shown that for a finite generation of the fractal, the exponent changes at sufficiently large wave vectors from the fractal dimension to four, the value given by the usual Porod law. It is shown that the number of particles of which the fractal is composed can be estimated from the value of the boundary between the fractal and Porod regions. The radius of gyration of the fractal is calculated analytically.Comment: 8 pages, 4 figures, accepted for publication in J. Appl. Crys

Atomic Force Microscopy Study of Nano-Physiological Response of Ladybird Beetles to Photostimuli

Background: Insects are of interest not only as the most numerous and diverse group of animals but also as highly efficient bio-machines varying greatly in size. They are the main human competitors for crop, can transmit various diseases, etc. However, little study of insects with modern nanotechnology tools has been done. Methodology/Principal Findings: Here we applied an atomic force microscopy (AFM) method to study stimulation of ladybird beetles with light. This method allows for measuring of the internal physiological responses of insects by recording surface oscillations in different parts of the insect at sub-nanometer amplitude level and sub-millisecond time. Specifically, we studied the sensitivity of ladybird beetles to light of different wavelengths. We demonstrated previously unknown blindness of ladybird beetles to emerald color (,500nm) light, while being able to see UV-blue and green light. Furthermore, we showed how one could study the speed of the beetle adaptation to repetitive flashing light and its relaxation back to the initial stage. Conclusions: The results show the potential of the method in studying insects. We see this research as a part of what might be a new emerging area of ‘‘nanophysiology’ ’ of insects

Эволюция озёр у ледника Джикиуганкез (Северное Приэльбрусье) в 1957–2020 гг. с учётом подземных каналов стока

Evolution of lakes near the Dzhikiugankez Glacier in the north of Elbrus for the period of 1957–2020 was studied using a comparative interpretation of aerial and satellite images as well as aerial and ground surveys in 2007–2018. Within this period the area of the Dzhikiugankez Glacier (43,35 N, 42,53 E) decreased by 8.2 km2. On the territory previously occupied by the glacier and close to it, 19 lakes appeared at different times, which dynamically developed and broke through. The lakes cover the area of 0.43 km2, that equals to 5.21% of the total icefree area. The average area of the lakes is 26.6 thousand m2. The maximum (the lake East Birdzhaly) is 89 thousand m2. In total there were six lakes larger than 25 thousand m2. They are concentrated in depressions on the surface of an ancient lava flow dammed by glaciers, dead ices and moraine lines. At a certain stage in the evolution of lakes, water from them penetrated through these barriers and, thus, formed subglacial and underground drainage channels. In 2013, during helicopter flights, an underground drainage channel with a length of more than 80 m was detected in the moraine line around the Lake «Podkova». The survey made possible to determine decreasing in the lake level by 2 m, and the accumulation of water with a volume of up to 48 thousand m3 in the cavities of the moraine massif, until it reaches the outer slope. The accumulated volume of water interflowed through the underground channel gradually, but despite the pot-holes on its bottom, no mudflow happened in the valley. Although in another case, the formation of an underground drainage channel from the Severnoye Chungurchat Lake was accompanied by a lake breakthrough and a mudflow. Other characteristic features of the evolution of lakes and changes in the direction of drainage from glaciers are also analyzed in the paper.По данным дешифрирования аэрофотоснимков и космических снимков за 1957–2020 гг., а также полевых наблюдений и вертолётных облётов определены особенности эволюции озёр у ледника Джикиуганкез и механизмы их прорыва, в том числе по подземным каналам. На примере озёр Подкова, Северное Чунгурчат и Балык Южное показано, что формирование подземных каналов стока не обязательно приводит к сходу селевых потоков, однако даже небольшие озёра могут быть очагами значительных селей

The research activities in Agrarian faculty of the Russian Peoples' Friendship University of 2011-2013

The analysis of the Russian Peoples' Friendship University Agrarian faculty research activities of 2011-2013