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To improve the dry friction behavior of traditional hard coatings, MoS2/PTFE lubricating coatings were prepared on the PVD TiN-coated cemented carbide using spray method. The influences of MoS2/PTFE lubricating coatings on the primary characteristics of TiN coatings were investigated. Reciprocating sliding tests were carried out with the TiN–MoS2/PTFE coated specimen (T-M-P) under dry sliding conditions, and the tribological behaviors were compared to those of the TiN-coated one (T-N). The test results indicated that the adhesion force of coatings with substrate for T-M-P specimen increased, the surface micro-hardness, roughness and friction coefficient significantly decreased. Meanwhile, the surface adhesions and abrasion grooves of T-M-P specimen were reduced, and the main wear forms of T-M-P were abrasion wear and coating delamination. The MoS2/PTFE lubricating coatings can be considered effective to improve the friction properties of traditional hard coatings.

In order to improve the tribological behavior of Si3N4/TiC ceramics, DLC coating was fabricated on the ceramic surface through magnetron sputtering technology. The surface and cross-section micrographs, the adhesion between coating and substrate, the surface roughness and microhardness of the DLC-coated ceramics were investigated. Reciprocating friction tests sliding against cemented carbide ball were conducted under dry sliding conditions. The test results indicated that the DLC coating possessed superior tribological performance, which was conductive to decreasing the friction coefficient and enhancing the wear resistance of ceramics. The primary mechanisms responsible for performance improvement of the DLC-coated ceramics were attributed to the combined effects of low shear stress, excellent adhesion with substrate, high microhardness and good surface roughness. It was believed that the DLC coating was efficient in improving the load-carrying capacity and expanding the application area of ceramic materials.

To enhance the tribological performance of Si3N4/TiC ceramics, MoS2/PTFE composite coatings were deposited on the ceramic substrate through spraying method. The micrographs and basic properties of the MoS2/PTFE coated samples were investigated. Dry sliding friction experiments against WC/Co ball were performed with the coated ceramics and traditional ones. These results showed that the composite coatings could significantly reduce the friction coefficient of ceramics, and protect the substrate from adhesion wear. The primary tribological mechanisms of the coated ceramics were abrasive wear, coating spalling and delamination, and the tribological property was transited from slight wear to serious wear with the increase of load because of the lower surface hardness and shear strength. The possible mechanisms for the effects of MoS2/PTFE composite coatings on the friction performance of ceramics were discussed.

Carbon materials are becoming the first choice for activating persulfate due to their environmental friendliness, high chemical stability, and metal-free leaching. However, the preparation of efficient carbon catalyst and the in-depth analysis for persulfate activation is still insufficient. Herein, N-doped porous carbons (NPCs) were prepared by the pyrolysis of polyacrylonitrile and used to trigger peroxymonosulfate (PMS) for degrading organic pollutants in water. The results showed that the optimized NPC-700, with large specific surface area, rich pore structure, high content of pyridinic N and graphitic N, as well as excellent oxygen-containing functional groups, possessed the best performance in activating PMS to degrade methylene blue (MB) with 99.15% degradation rate in 30 min. Furthermore, the NPC-700 delivered high stability under a wide pH from 3.51 to 11.15. The radical quenching experiments and electron paramagnetic resonance (EPR) spectroscopy revealed that •OH, O2•-, SO4•- and 1O2 active species were involved in the catalytic oxidation of MB. Besides, the NPC-700/PMS system exhibited excellent degradation performance for various organic dyes, including rhodamine B, acid orange 7, and methyl orange. This study not only provides a promising metal-free catalyst for the removal of organic pollutant in water, but also promotes the sustainable development of carbon-based materials.

IL-17RB, a member of the IL-17 receptor family that can be activated by IL-17B, has been proved to be involved in inflammatory diseases and cancers. However, the function of IL-17RB in thyroid cancer is still unknown. In this study, IL-17RB expression in thyroid cancer cell lines and tissues was examined by real-time PCR and western blot. The effects of IL-17RB on cell invasion and migration were determined by in vitro invasion and migration assays, while the effects of IL-17RB on cell metastasis were analyzed by in vivo experiments. The results showed that IL-17RB expression was upregulated in both thyroid cancer cells and tissues. IL-17B dose-dependently promoted the invasion, growth and migration of thyroid cancer cells, whereas knockdown of IL-17RB attenuated the effects of IL-17B in vitro. Moreover, IL-17RB was involved in the metastasis and growth of thyroid cancer cells in vivo. In addition, IL-17RB induced ERK1/2 activation and increased MMP-9 expression in vitro and in vivo. Inhibition of ERK1/2 pathway blocked the IL-17RB-mediated thyroid cancer cell invasion and MMP-9 expression. Together, our findings demonstrate that IL-17RB can enhance thyroid cancer cell invasion and metastasis via ERK1/2 pathway-mediated MMP-9 expression, suggesting that IL-17RB may act as a potential therapeutic target for thyroid cancer therapy.

We propose a simple but effective implicit-surface-based (ISB) method for constructing composite porous scaffolds (including gradient, hybrid, hierarchical, stochastic porous structures, or their combinations) based on a certain number of control elements (points, line segments, polylines, polygons, etc.) that are provided by users. Our method efficiently integrates spatial partitioning and substructure assignments in an easy manner. Users need not consider complex transitions between substructures during design, as these are naturally constructed. Also, our method can easily reconstruct native tissue structures based on micro-CT data. Here we successfully fabricated porous scaffolds with polymer as well as titanium using additive manufacturing (AM) techniques for ready use in tissue engineering.

Here we propose an effective and succinct method to generate graded porous material architectures in a mathematical way. Pores with gradient pore sizes, types, orientations and porosities can be integrated to create a single architecture. The resulting structures can be readily produced by using additive manufacturing (AM) techniques for medical applications. We give relevant examples of constructing several kinds of gradient porous scaffolds and discuss their respective characteristics for use in cell culture studies.