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Purpose The shapes of surface textures have been designed to control the leakage of mechanical seals in recent years. The purpose of this paper is to demonstrate the influence of geometric properties of elliptical dimples on the leakage rate. Design/methodology/approach A new geometric feature point is expressed using an analytical solution to locate the high-pressure zones. Furthermore, a numerical model of the three-dimensional flow field for the mechanical seal with elliptical dimples is developed using ANSYS Fluent to demonstrate the influencing mechanism. Findings The location of the proposed geometric converging point coincides with the maximum pressure point under different orientation angles. An inward flow on the leakage section observed from the simulation results is responsible for decreasing the leakage rate. Originality/value The influencing mechanism of the elliptical dimple on the leakage rate is demonstrated, which can facilitate the design of surface textures.

Body-protective compound (BPC) 157 demonstrates protective effects against damage to various organs and tissues. For future clinical applications, we had previously established a solid-phase synthesis process for BPC157, verified its biological activity in different wound models, and completed preclinical safety evaluations. This study aimed to investigate the pharmacokinetics, excretion, metabolism, and distribution profiles of BPC157. After a single intravenous (IV) administration, single intramuscular (IM) administrations at three doses in successive increments along with repeated IM administrations, the elimination half-life (t1/2) of prototype BPC157 was less than 30 min, and BPC157 showed linear pharmacokinetic characteristics in rats and beagle dogs at all doses. The mean absolute bioavailability of BPC157 following IM injection was approximately 14%–19% in rats and 45%–51% in beagle dogs. Using [3H]-labeled BPC157 and radioactivity examination, we proved that the main excretory pathways of BPC157 involved urine and bile. [3H]BPC157 was rapidly metabolized into a variety of small peptide fragments in vivo, thus forming single amino acids that entered normal amino acid metabolism and excretion pathways. In conclusion, this study provides the first analysis of the pharmacokinetics of BPC157, which will be helpful for its translation in the clinic.