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Abstract: The articulating components of artificial joints consist mainly of metals, ceramics, or polymers. Resulting abrasive wear particles can promote osteolysis and aseptic loosening of the endo‐prosthetic implants. Ultra‐high‐molecular‐weight‐polyethylene is the material used most for bearing couples in total hip replacement. In the present study, three types of polyethylene (PE) liners varying in material composition, i.e., (1) conventional PE (C‐PE), (2) sequentially cross‐linked PE (SX‐PE), (3) cross‐linked PE blended with vitamin E (EX‐PE) articulating with two types of femoral heads were used. After ultrasound treatment of each simulator lubricant, different concentrations (0.1/0.25/0.5/1.0 mL) were taken and dissolved in hydrochloric acid (37%) in a similar manner. The aim was to analyze the characteristics of wear particles generated in a hip simulator, with respect to different volumes of the lubricant. Within the scope of particle analysis, distinct alterations for particle characteristics were determined in the lubricant volumes and types of PE material used. A significant decrease in particle number for SX‐PE liners, compared to the C‐PE inserts and even more for EX‐PE inserts, was detected at each lubricant volume. Particle morphologies varied depending on PE material. Alterations in particle size and other morphologic parameters between the four tested volumes, could be proven for each PE type. In general, particle sizes and parameters (e.g., length and width) increased with increasing serum volumes. In conclusion, the chosen volume of the simulator lubricant used for particle analysis has a crucial influence on detected particle number, size distribution, and morphologic parameters. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1299–1306, 2018. [ABSTRACT FROM AUTHOR]

Oxygen removal to very low residual contents in methane-rich gas streams and carbon dioxide as co-component (simulated biogas) was achieved via three different methods at various temperatures, namely, by reduction with hydrogen admixtures on Pt/ γ-Al2O3 catalysts, by oxygen absorption affinity of YBaCo4O7+ δ, and by the catalytic reaction with methane on both the materials, respectively. The three methods have characteristic advantages and disadvantages which are discussed in the context of existing methods for gas treatments focused on oxygen removal. Finally, the advantage of dielectric radio-frequency heating on the powdered functional materials is suggested as alternative to conventional routes. [ABSTRACT FROM AUTHOR]

Twelve patients underwent an osteosynthesis with titanium to treat upper and lower jaw fractures. Six to 12 months later, the miniplates were removed. Tissue samples were analyzed by light and electron microscopy for detection of a metallosis. The analysis showed new bone formation like callus tissue around the miniplates. In some cases small, rounded deposits and accumulation of colloid-like particles located next to bigger titanium artifacts were detected in the cytoplasm of histiocytes and in the matrix of connective tissue. The titanium was identified by elemental analysis using EDX in SEM as well as by EELS and electron diffraction in TEM. Both kinds of particles contain titanium, but they seem to be different in composition and derivation. The bigger particles seem to consist of metallic titanium and sourced by working on the metallic implants during the implantation itself. On the other hand, the colloidal-like, small, rounded particles in tissue macrophages and outside the cells in the matrix of connective tissue are presumably of other origin; for example, they could be derived from biodegradation and chemical conversion of the metallic implants. The titanium miniplates were examined before and after implantation by using ESCA technique and revealed metallic titanium and different compositions with other elements. The amount of titanium load of the tissue was very low in most cases and presumably not of biomedical relevance. [ABSTRACT FROM AUTHOR]