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This paper contains an extended presentation of a new approach to the macroscopic description of anisotropic pore space structure of rigid permeable material, utilizing the concept of Minkowski metric space. The metrics of the Minkowski and Euclidean spaces are used to determine double measures of any line, surface and volume elements, and to define geometrical macro-parameters characterizing anisotropic pore space structure: the volume and surface porosities, and the tortuosity of the pores. It is shown that the metric tensor of the Minkowski space can be interpreted as a tensor of the pore tortuosity, and its inverse as a tensor of the surface porosity. This means that the pore tortuosity has a pure geometrical character and is of fundamental importance for description of anisotropic pore space structure and for all physical processes taking place in the pore space. The approach presented in this paper allows a description of fluid dynamics in the anisotropic pore space in the framework of rational mechanics. [ABSTRACT FROM AUTHOR]

In the majority of pharmaceutical applications, polymers are employed extensively in a diverse range of pharmaceutical products, serving as indispensable components of contemporary solid oral dosage forms. A comprehensive understanding of the properties of polymers and selection the appropriate methods of characterization is essential for the design and development of novel drug delivery systems and manufacturing processes. Orally disintegrating film (ODF) formulations are considered to be a potential substitute to traditional oral dosage forms and an alternative method of drug administration for children and uncooperative adult patients, including those with swallowing difficulties. A multitude of pharmaceutical formulations with varying mechanical and biopharmaceutical properties have emerged from the modification of the original polymeric bulk. Here we propose different formulation approaches, i.e. solvent casting (SC), 3D printing (3DP), electrospinning (ES), and lyophilization (LP) that enabled us to adjust the disintegration time and the release profile of poorly water soluble haloperidol (HAL, BCS class II) from PVA (polyvinyl alcohol) based polymer films while maintaining similar hydrogel composition. In this study, the solubility of haloperidol in aqueous solution was improved by the addition of lactic acid. The prepared films were evaluated for their morphology (SEM, micro-CT), physicochemical and biopharmaceutical properties. TMDSC, TGA and PXRD were employed for extensive thermal and structural analysis of fabricated materials and their stability. These results allowed us to establish correlations between preparation technology, structural characteristics and properties of PVA films and to adapt the suitable manufacturing technique of the ODFs to achieve appropriate HAL dissolution behaviour., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Thin-walled and thick-walled microcellular moldings were obtained by MuCell ® technology with nitrogen as a supercritical fluid. 2 mm thick polyamide 6 (PA6) with 30% wt. glass fiber (GF) samples were cut from automotive industrial elements, while 4 mm, 6 mm, and 8.4 mm thick moldings of PA6.6 with 30% wt. GF were molded into a dumbbell shape. The internal structure was investigated by scanning electron microscopy (SEM) and X-ray computed microtomography (micro-CT) and compared by numerical simulations for microcellular moldings using Moldex3D ® 2022 software. Young's modulus, and tensile and impact strength were investigated. Weak mechanical properties of 2 mm thick samples and excellent results for thick-walled moldings were explained. SEM pictures, micro-CT, and simulation graphs revealed the tendency to decrease the cell size diameter together with increasing sample thickness from 2 mm up to 8.4 mm.

Ce 3+ doped Al 2 O 3 -YAG eutectics were successfully grown by the horizontal directional crystallization method. The crystallization rate of eutectic growth was changed in the 1-7.5 mm/h range at a growth temperature of 1835 ℃. The microstructure of eutectic samples was investigated using scanning electron microscopy and X-ray microtomography. The intrinsic morphology of eutectic represents the stripe-like channel structure with a random distribution of the garnet Y 3 Al 5 O 12 (YAG) and Al 2 O 3 (sapphire) phases. The content of these phases in the stripes changes in the 52.9-55.3% and 46.1-47.1% ratios, respectively, depending on the growth rate of the crystallization of the eutectic samples. The luminescent properties of the eutectic demonstrated the dominant Ce 3+ luminescence in the garnet phase. The luminescence of the Ce 3+ ions in Al 2 O 3 has also been observed and the effective energy transfer processes between Ce 3+ ions in the Al 2 O 3 and YAG garnet phases were revealed under high-energy excitation and excitation in the UV Ce 3+ absorption bands of sapphire. The phosphor conversion properties and the color characteristics (Al 2 O 3 -YAG):Ce eutectic with different thicknesses were investigated under excitation by a blue LED. We have also tested the prototypes of white LEDs, prepared using a blue 450 nm LED chip and (Al 2 O 3 -YAG):Ce eutectic photoconverters with 0.15 to 1 mm thicknesses. The results of the tests are promising and can be used for the creation of photoconverters for high-power white LEDs.

The paper shows that osteoporosis (OA) changes the SF content and the lipid profile substantially. To estimate the implication of the lipid environment in case the articular cartilage (AC) changes, we measured friction coefficient normal samples, with early and late stages of (OA). During joint inflammation and osteoarthritis, enzymatically activated β 2 -Glycoprotein I is transformed into antibody conformation. Our hypothesis about cartilage degradation of PL bilayers by antibodies (β 2 -Glycoprotein I) is considering antiphospholipid syndrome (APS), which was not discussed in the literature before. Deactivated PL molecule has no ability to form bilayers, lamellar phases, and liposomes. The phospholipid content in synovial fluid (SF) during joint inflammation, osteoarthritis, and rheumatoid arthritis is significantly higher (2-3 times) above the normal concentration of PL, and has a poor boundary-lubricating ability is deactivated., (Copyright © 2018. Published by Elsevier B.V.)

A one-dimensional problem of propagation of plane harmonic wave in macroscopically inhomogeneous materials is analyzed. A general description is proposed for the material of the equivalent fluid type characterized locally by two acoustical parameters: the wavenumber and the acoustical impedance. The coupled system of ordinary differential equations for amplitudes of forward and backward waves is derived. As an example the problem of wave interaction with a layer of inhomogeneous material placed between two homogeneous halfspaces is considered. The analytical solution and explicit expressions for reflection and transmission coefficients are obtained. It is shown that the presence of the inhomogeneous transition layer causes strong frequency dependence on both coefficients.