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The paper deals with the study of the features of the process of YAG phase formation via the Solid-State Reaction (SSR) method according to the proposed multi-stage scheme, including three stages of various mechanical and thermal processing (pre-milling in a ball mill for 24, 48 and 72 h, as well as firing at 1150 °C, 1250 °C, and 1450 °C with intermediate grinding step). The commercial micrometer-sized Y2O3and Al2O3powders were used as starting materials. The phase transformation was monitored by the X-ray diffraction in each synthesis stage. The microstructure and elemental distribution of samples were studied by scanning electron microscopy and energy-dispersive X-ray spectrometry. During the work, we found the dual effects of partially reacted mixture grinding, which can accelerate or slow down the synthesis rate depending on the YAG content in the preceding stage. We have proposed a simple model including the concept of “critical YAG concentration”. When the lower limit of this parameter (over 60 %) is reached, grinding has a negative effect on the further course of the SSR.  Carrying out the synthesis according to a three-stage scheme makes it possible to obtain a product with a YAG content above 90 %, regardless of the pre-milling time, and the use of a two-stage synthesis scheme provides a monophasic raw material (99 % of YAG) suitable for further single crystals growth. The increased efficiency of the multi-stage YAG synthesis scheme was demonstrated in comparison with the conventional one-stage obtaining process that yielded only up to 60% of the target phase in the temperature range up to 1500 °C.

Quantitative description of hepatic microvascular bed could contribute to understanding perfusion CT imaging. Micro-CT is a useful method for the visualization and quantification of capillary-passable vascular corrosion casts. Our aim was to develop and validate open-source software for the statistical description of the vascular networks in micro-CT scans. Porcine hepatic microvessels were injected with Biodur E20 resin, and the resulting corrosion casts were scanned with 1.9–4.7 $$\upmu \hbox {m}$$ μm resolution. The microvascular network was quantified using newly developed QuantAn software both in randomly selected volume probes (n= 10) and in arbitrarily outlined hepatic lobules (n= 4). The volumes, surfaces, lengths, and numbers of microvessel segments were estimated and validated in the same data sets with manual stereological counting. Calculations of tortuosity, radius histograms, length histograms, exports of the skeletonized vascular network into open formats, and an assessment of the degree of their anisotropy were performed. Within hepatic lobules, the microvessels had a volume fraction of 0.13 $$\pm $$ ± 0.05, surface density of 21.0 $$\pm $$ ± 2.0 $$\hbox {mm}^{-1}$$ mm-1 , length density of 169.0 $$\pm $$ ± 40.2 $$\hbox {mm}^{-2}$$ mm-2 , and numerical density of 588.5 $$\pm $$ ± 283.1 $$\hbox {mm}^{-3}$$ mm-3 . Sensitivity analysis of the automatic analysis to binary opening, closing, threshold offset, and aggregation radius of branching nodes was performed. The software QuantAn and its source code are openly available to researchers working in the field of stochastic geometry of microvessels in micro-CT scans or other three-dimensional imaging methods. The implemented methods comply with reproducible stereological techniques, and they were highly consistent with manual counting. Preliminary morphometrics of the classical hepatic lobules in pig were provided.

Multi-polar space is a generalization of the notion of vector space. In this paper, we deal with a three-polar vector space over a semi-field of double (hyperbolic complex) numbers. We introduce and study operations of addition and multiplication such that they form a commutative ring with unit on the three-polar space

Our aim was to use stereology to quantify the volume fraction of osteocyte lacunes, volume fraction of large blood vessels, numerical density of osteocyte lacunes, volume of osteocyte lacunae and bone surface in series of micro-CT images representing samples of spongy and compact bone of human tibia. The spongy bone had a smaller volume fraction of osteocyte lacunes, a greater numerical density of bone lacunes, a smaller volume of the lacunes within the same bone volume and a greater bone surface density when compared to the compact bone. Stereology provided us with data on hierarchical organization of bone structural heterogeneity with reasonable time costs.

We used corrosion casts and micro-CT for quantitative description of microvascular network in porcine liver. Using stereological methods, manual tracing of microvessels and analysis of orientation in 3D, we quantified the volume fraction, the surface density, the numerical density, the length density and the tortuosity of microvessels in series of images with 1.875 μm pixel resolution. Biodur E 20 resin was more suitable for preparing and quantifying microvascular tree corrosion casts when compared to Mercox II resin. Quantified data could be applicable for correlating 3D models with 2D liver histopathology, for enhancing the interpretation of routine medical CT and for providing data for computer models of tissue perfusion and angiogenesis.

Toxicity and accumulation of Cd2+in yeasts were studied in eight different yeast species. The adaptation to toxic concentration of this metal was dependent on the production of extracellular yeast glycoproteins. The highest concentration of Cd2+ions in the growth medium was tolerated by a Hansenula anomala, strain while the lowest tolerance was found by the strain of species Saccharomyces cerevisiae. Extracellular glycoproteins of Hansenula anomala absorbed nearly 90% of the total content of Cd2+ions bound by yeast cells, while extracellular glycoproteins of Saccharomyces cerevisiae bound only 6% of the total amount of cadmium. This difference is caused by the variable composition of the saccharide moiety in the extracellular glycoproteins. The composition of extracellular glycoproteins changed during the adaptation of the yeast cells to the presence of Cd2+ions.