Although the pericentromeric regions of chromosomes that are enriched in tandemly repeated satellite DNA represent a significant part of eukaryotic genomes, they remain understudied, which is mainly due to interdisciplinary knowledge gaps. Recent studies suggest their important role in genome regulation, karyotype stability, and evolution. Thus, the idea of satellite DNA as a junk part of the genome has been refuted. The integration of data regarding molecular composition, chromosome behaviour, and the details of the in situ organization of pericentromeric regions is of great interest. The objective of this work was a cytogenetic analysis of the interactions between pericentromeric regions from non-homologous chromosomes in mouse spermatocytes using immuno-FISH. We analysed two events: the associations between centromeric regions of the X chromosome and autosomes and the associations between the centromeric regions of the autosomal bivalents that form chromocenters. We concluded that the X chromosome forms temporary synaptic associations with different autosomes in early meiotic prophase I, which can normally be found until the pachytene–diplotene, without signs of pachytene arrest. These associations are formed between the satellite-DNA-rich centromeric regions of the X chromosome and different autosomes but do not involve the satellite-DNA-poor centromeric region of the Y chromosome. We suggest the hypothetical model of X chromosome competitive replacement from such associations during synaptic correction. We showed that the centromeric region of the X chromosome in association remains free of γH2Ax-dependent chromatin inactivation, while the Y chromosome is completely inactivated. This finding highlights the predominant role of associations between satellite DNA-rich regions of different chromosomes, including the X chromosome. We suppose that X-autosomal transient associations are a manifestation of an additional synaptic disorder checkpoint. These associations are normally corrected before the late diplotene stage. We revealed that the intense spreading conditions that were applied to the spermatocyte I nuclei did not lead to the destruction of stretched chromatin fibers of elongated chromocenters enriched in satellite DNA. The tight associations that we revealed between the pericentromeric regions of different autosomal bivalents and the X chromosome may represent the basis for a mechanism for maintaining the repeats stability in the autosomes and in the X chromosome. The consequences of our findings are discussed.

In this paper, we consider the proposed method for identifying the average integral heat transfer coefficient of an axial heat pipe (ATT) coolant to a capillary—porous wick as a function of temperature. The purpose of axial heat pipes is to divert thermal energy from the heat-generating equipment and redistribute it over the surface of the radiator to ensure the regular functioning of the thermostatically controlled equipment. This problem is solved by determining the global extremum of the RMS functional of the discrepancy between the theoretical and experimental temperature field at the temperature sensor installation sites. The method of thermal balances was chosen as a method for solving the “direct” problem of heat transfer inside a heat pipe, and the gradient method of conjugate directions was chosen as an optimization method, as the most accurate method of the first order of convergence of the iterative process. As a criterion for stopping the iterative process, a superposition of errors is used that introduce incorrectness into the studied formulation of the heat transfer problem, such as systematic, error in the formulation of the “direct” heat transfer problem, etc. The resulting identified solution is compared with the classical experimental method for determining the heat transfer coefficient based on the analysis of thermal resistances of the structure.