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Crystal structures of Ca2SiO4, Na2SO4–K2SO4 sulfates, and related minerals bubnovaite K2Na8Ca(SO4)6 and dobrovolskyite Na4Ca(SO4)3 were described as consisting of microblocks for the first time. A microblock [M(TO4)6] that consisted of an octahedron interlinked by six vertices with six adjacent tetrahedra was considered a structural unit inherited upon cooling from a high-temperature disordered parent unit. The relationship between the parent and inherited microblocks was established. Based on this relationship, 15 possible types of microblocks maintaining a trigonal symmetry were derived. The minerals and compounds structurally related to α-Na2SO4-derived superstructures were formed as a result of the cooling of the high-temperature phases containing the disordered parent microblock. Here, the inheritance driving force was the tendency of the structure to become ordered upon cooling. The reasons for the formation of a microblock from the parent microblock were mainly determined by the ionic radius and type of cation occupying the octahedral site. The identification of minerals with the described structural features could be a promising tool for the synthesis of novel compounds with useful properties. [ABSTRACT FROM AUTHOR]

The clinical application of mesenchymal stem cells (MSCs) is attracting attention due to their excellent safety, convenient acquisition, multipotency, and trophic activity. The clinical effectiveness of transplanted MSCs is well-known in regenerative and immunomodulatory medicine, but there is a demand for their improved viability and regenerative function after transplantation. In this study, we isolated MSCs from adipose tissue from three human donors and generated uniformly sized MSC spheroids (∼100 µm in diameter) called microblocks (MiBs) for dermal reconstitution. The viability and MSC marker expression of MSCs in MiBs were similar to those of monolayer MSCs. Compared with monolayer MSCs, MiBs produced more extracellular matrix (ECM) components, including type I collagen, fibronectin, and hyaluronic acid, and growth factors such as vascular endothelial growth factor and hepatocyte growth factor. Subcutaneously injected MiBs showed skin volume retaining capacity in mice. These results indicate that MiBs could be applied as regenerative medicine for skin conditions such as atrophic scar by having high ECM and bioactive factor expression.

The main difficulties of application of high-frequency (HF) heating for sealing by soldering of microblock packages made of aluminum alloys is the low efficiency of heating, long processing time and considerable heating of the internal electronic module while sealing. The purpose of this study was to use effectively the physical phenomena of HF heating in order to optimize the HF heating parameters of sealing by soldering using fusible solders of microwave microblock packages made of diamagnetic alloys. Effects of HF heating (superficial, proximity and concentration of power lines) of the electromagnetic field are applied to sealing using soldering of microwave microblock packages made of diamagnetic alloys. The optimized parameters of HF heating provide energy efficiency and productivity of sealing: frequency of the electromagnetic field and the inductor design. When soldering microelectronic devices containing electronic parts sensitive to the electric field component, the energy of electromagnetic field in the package should be significantly lower than the energy of elements degradation, in which case the skin layer reaches the field penetration depth which is equal to 4 package thickness values. In order to increase the HF heating efficiency, there should be a concentration of the inductor current on the package surface facing the inductor, which is done by using a ferrite magnetic core. Using a ferrite magnetic core inside the inductor concentrates tension of magnetic field due to concentration of power lines of magnetic field in 1,2-1,3 times. The optimal frequency range for HF soldering is 0,4-2,0 MHz when at electromagnetic field penetration depth into the material of the package equal to 4 thickness values of the skin layer, the field strength is 152 times weaker in comparison with the surface.

The clinical application of mesenchymal stem cells (MSCs) is attracting attention due to their excellent safety, convenient acquisition, multipotency, and trophic activity. The clinical effectiveness of transplanted MSCs is well-known in regenerative and immunomodulatory medicine, but there is a demand for their improved viability and regenerative function after transplantation. In this study, we isolated MSCs from adipose tissue from three human donors and generated uniformly sized MSC spheroids (∼100 µm in diameter) called microblocks (MiBs) for dermal reconstitution. The viability and MSC marker expression of MSCs in MiBs were similar to those of monolayer MSCs. Compared with monolayer MSCs, MiBs produced more extracellular matrix (ECM) components, including type I collagen, fibronectin, and hyaluronic acid, and growth factors such as vascular endothelial growth factor and hepatocyte growth factor. Subcutaneously injected MiBs showed skin volume retaining capacity in mice. These results indicate that MiBs could be applied as regenerative medicine for skin conditions such as atrophic scar by having high ECM and bioactive factor expression., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Park, Lee, Park, Yoo, Kwon, Park, Kang, Lee and Cho.)