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The resolution of inflammation, as part of standard host defense mechanism, is the process to guarantee timely termination of inflammatory responses and eventual restoration of tissue homeostasis. It is mainly achieved via efferocytosis, during which pro-resolving macrophages clear apoptotic neutrophils at the inflammatory site. Unfortunately, impaired resolution can be the leading cause of chronic inflammatory disorders and some autoimmune diseases. Existing studies have provided relatively comprehensive understandings about the recognition and uptake of apoptotic neutrophils by macrophages during early phases of efferocytosis. However, lack of information concerns macrophage metabolism of apoptotic cell-derived metabolites after being released from phagolysosomes or the relationship between such metabolism and efferocytosis. Notwithstanding, three recent studies have revealed macrophage metabolism of cholesterol, fatty acids and arginine, as well as their respective functions in the context of inflammation-resolution. This review provides an overview of the resolution of inflammation, efferocytosis and the key players involved, followed by a focus on the metabolism of apoptotic cell-derived metabolites within efferocytes. Hypotheses of more potential apoptotic cell-derived metabolites and their possible roles in the resolution are also formulated. Understanding the effect of these metabolites further advances the concept that apoptotic cells act as active players to regulate resolution, and also suggests novel therapeutic strategies for diseases driven by defective resolution and even cancer that may be treated through enhanced efferocytosis. [Display omitted] • Efferocytosis aimed at apoptotic cell clearance is the key process in inflammation resolution. • Apoptotic cells act as active players in regulating the resolution of inflammation. • Macrophage metabolism of apoptotic cell-derived metabolites promotes the resolution of inflammation via various pathways. [ABSTRACT FROM AUTHOR]

Abstract Eu2+/Eu3+ ions doped silica glasses contained In 2 O 3 nanoparticles (NPs) have been fabricated by using nanoporous silica glasses. Interestingly, efficient energy transfer from In 2 O 3 NPs to Eu2+/Eu3+ ions enhanced the photoluminescence (PL) emission of Eu2+/Eu3+ ions, which derives from lattice defects in In 2 O 3 NPs. Our work has not only demonstrated a facile way to fabricate NPs and rare earth ions co-doped silica glasses, but also extended the applications of semiconductor oxide NPs such as In 2 O 3 NPs. [ABSTRACT FROM AUTHOR]

Complex silicon carbide (SiC) ceramic components are difficult to fabricate due to their strong covalent bonds. Binder jetting (BJ) additive manufacturing has the outstanding advantages of high forming efficiency and no thermal deformation, especially suitable for printing complex structure SiC components. This study tried to obtain low silicon content silicon carbide ceramics by binder jetting followed by phenolic resin impregnation and pyrolysis (PRIP) and liquid silicon infiltration (LSI). BJ was used for the SiC green parts fabrication, and the highest compressive strength (7.7 ± 0.3 MPa) and lowest dimensional deviations (1.2–1.6 mm) were obtained with the printing layer thickness of 0.15 mm. Subsequently, PRIP treatments were introduced to increase the carbon content for the following LSI process. As the number of PRIP cycles increased, the carbon density of SiC/C preform increased and the porosity decreased. After the LSI treatment, the final Si-SiC composites processed with 2 PIRP cycles reached the highest flexural strength (257 ± 14.26 MPa) and the best wear resistance. This was attributed to the low residual silicon content (10.2 vol%) and almost no residual carbon. Furthermore, several complex structural components were fabricated using these methods. The preparation of complex components verifies the feasibility of BJ and LSI for manufacturing high-strength and high-precision SiC ceramics. Besides, this work hopes to provide technical guidance for the preparation of complex SiC composites in the future. • Si-SiC composites were fabricated by the binder jetting and liquid silicon infiltration. • The ultimate flexural strength and wear resistance were enhanced simultaneously. • Several representative complex structures (optical mirror, turbine disc, and topology) were fabricated. [ABSTRACT FROM AUTHOR]

• Introduced bimodal SiC powder, enhancing BJ process and powder properties. • All stages of microstructure and performance are investigated. • The flexural strength and fracture toughness increased by 42.3 % and 25.3 %. Binder jetting (BJ) additive manufacturing has emerged as a promising technique for batch production of complex silicon carbide (SiC) ceramic components. However, the utilization of coarse powder in BJ often leads to lower density and strength in green parts and final composites compared to conventional fabrication methods. This study aims to enhance the mechanical performance of SiC ceramics through a novel bimodal SiC powder formulation for BJ, complemented by phenolic resin impregnation and pyrolysis (PRIP) and liquid silicon infiltration (LSI). The optimal ratio of bimodal powder, comprising 75 % coarse and 25 % fine powder, was determined through a comprehensive analysis of the microstructure and properties at various stages of the preparation process. The bimodal powder achieves a packing density of 48.3 % and exhibits satisfactory flowability. Notably, the density of the green part reaches 1.78 g/cm3, which is 31 % and 4.7 % higher than that of unimodal fine and coarse powders, respectively. Following the LSI process, the final Si-SiC composites display a high flexural strength of 276.6 ± 13.3 MPa and fracture toughness of 3.52 ± 0.12 MPa·m1/2. These values represent increases of 42.4 % and 25.3 %, respectively, compared to the composites derived from unimodal coarse powder. The material compositions and fabrication strategies proposed in this work offer an effective pathway for creating high-performance SiC ceramic composites via binder jetting. [Display omitted] [ABSTRACT FROM AUTHOR]

Dynamic analysis and optimization can improve the stability of gyratory crushers. In this research, a multibody dynamic (MBD) model of a gyratory crusher was built for motion simulation, and the discrete element method (DEM) was applied to describe ore breakage numerically. Specifically, both the stiffness and damping parameters were defined for vibration analysis. A bonding particle model (BPM) was used to extract the distributed breaking force. Then, actual production data was taken to determine the value ranges of key parameters in the established DEM-MBD co-simulation system such as the self-rotation friction coefficient of the mantle, stiffness and damping of the base. Furthermore, the influence of the horizontal stiffness and damping parameters on the vibration of the gyratory crusher was analyzed using the co-simulation results. A dynamic performance prediction model of the gyratory crusher was established using the kriging interpolation method. Finally, based on the prediction model, the particle swarm optimization (PSO) algorithm was applied for the multi-objective optimization of the gyratory crusher. The simulation results indicate that mantle movement is influenced by the horizontal stiffness and damping parameters, which became more complex with the extension of breaking time. The interaction between the stiffness coefficient and the damping coefficient in the Z direction significantly influences productivity. Additionally, horizontal vibrations are significantly affected by the damping coefficient in the Z direction. After optimization, the productivity increased by 10.96 %, the root mean square (RMS) value of the vibration velocity in the X direction decreased by 21.12 %, and that in the Z direction decreased by 4.21 %. [ABSTRACT FROM AUTHOR]