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Heterotopic ossification (HO) comprises the abnormal formation of ectopic bone in extraskeletal soft tissue. The factors that initiate HO remain elusive. Herein, we found that calcified apoptotic vesicles (apoVs) led to increased calcification and stiffness of tendon extracellular matrix (ECM), which initiated M2 macrophage polarization and HO progression. Specifically, single‐cell transcriptome analyses of different stages of HO revealed that calcified apoVs were primarily secreted by a PROCR+ fibroblast population. In addition, calcified apoVs enriched calcium by annexin channels, absorbed to collagen I via electrostatic interaction, and aggregated to produce calcifying nodules in the ECM, leading to tendon calcification and stiffening. More importantly, apoV‐releasing inhibition or macrophage deletion both successfully reversed HO development. Thus, we are the first to identify calcified apoVs from PROCR+ fibroblasts as the initiating factor of HO, and might serve as the therapeutic target for inhibiting pathological calcification. [ABSTRACT FROM AUTHOR]

In order to realize the large-scale and high-value utilization of waste architectural ceramics, high-temperature resistant materials based on waste architectural ceramics were prepared with sodium silicate as the binder, clay/bauxite and metakaolin/bauxite as coating materials, and the cold strength obtaining mechanism was explored. The phase composition, the microstructure and the mechanical properties of the high temperature resistant materials based on waste architectural ceramics were tested and analyzed. The results showed that when the heat treatment temperature was between 110-1 000, the strength of the samples mainly came from the physical adhesion of sodium silicate and fine powder. When the temperature rose to 1 100, the strength of the sample was improved since the internal low-melting-point components melted and promoted sintering. The addition of clay and bauxite can effectively enhance the flexural strength of the samples when the heat treatment temperature is 1 000. When the heat treatment temperature rises from 900 to 1 000, the flexural strength of the samples will be enhanced owing to the formation of silica alumina spinel and mullite from metakaolin. [ABSTRACT FROM AUTHOR]

The progress of research and production of bauxite based homogenized grogs in China was summarized and the achievements of their application and modification in recent years were epitomized. In combination with the shortcomings existing in the research, production and application, the suggestions of bauxite based homogenized grogs for future development were put forward. [ABSTRACT FROM AUTHOR]

The corundum-mullite bricks were prepared using brown corundum, α-AI2O3 powder, andalusite powder, and Guangxi white mud as raw materials. In order to improve the iron slag erosion and corrosion resistance of corundum-mullite bricks, 2 mass% Si powder was introduced into the corundum-mullite bricks, and the properties of the samples were compared before and after Si powder addition. The results show that compared with the corundum-mullite sample without Si powder, the sample with Si powder has uniform and small pores, and the apparent porosity decreases from 15.8% to 13.5%, the cold compressive strength increases obviously, the hot modulus of rupture increases by 5.6 times, the hot toughness and the iron slag corrosion resistance and the penetration resistance are obviously improved. [ABSTRACT FROM AUTHOR]

Recycled SiO2 micropowder solid waste (SiO2<85 mass%) was heat treated at 400,500,600,700,800,900, and 1 000 °C for 5 h, respectively, and then the heat treated powders were analyzed. The results show that the samples are gradually sintered as the heat treatment temperature increases. Below 800 °C, the original structure of granular and spherical SiO2 aggregates remains. However, at 500 °C or below, the aggregates strength is low. Above 800 °C, SiO2 micropowder agglomerates seriously and cristobalite is precipitated. When the heat treatment temperature is in the range of 600-800 °C, the spherical SiO2 micropowder with a certain strength and the bulk density of 0.73-0.95 g · cm-3 and a core-shell structure can be prepared, which can be used as a lightweight raw material for low temperature insulation castables and as a filler for other industries. [ABSTRACT FROM AUTHOR]

Periclase-spinel bricks were prepared using sintered magnesia, flotation magnesia, fused magnesium aluminate spinel and calcined Al2O3 fines as starting materials and calcium lignosulfonate as the binder, mixing, shaping and firing at 1 650 °C.Flotation magnesia particles were used to replace ordinary sintered magnesia particles and different amounts of calcined Al2O3 fines were extraadded (0%,3% and 5%, by mass) to investigate their effects on the properties of periclase-spinel bricks. The results show that:(1)the periclase-spinel bricks prepared with flotation magnesia particles have reduced apparent porosity and cold compressive strength, and enhanced bulk density, thermal shock resistance, hot strength and hot toughness;(2)in the periclase-spinel bricks prepared with flotation magnesia particles, as the calcined Al2O3 fines addition increases, the apparent porosity and the cold compressive strength decrease, and the bulk density, the thermal shock resistance, the hot strength and the hot toughness are improved. [ABSTRACT FROM AUTHOR]

Heterotopic ossification (HO) comprises the abnormal formation of ectopic bone in extraskeletal soft tissue. The factors that initiate HO remain elusive. Herein, we found that calcified apoptotic vesicles (apoVs) led to increased calcification and stiffness of tendon extracellular matrix (ECM), which initiated M2 macrophage polarization and HO progression. Specifically, single-cell transcriptome analyses of different stages of HO revealed that calcified apoVs were primarily secreted by a PROCR + fibroblast population. In addition, calcified apoVs enriched calcium by annexin channels, absorbed to collagen I via electrostatic interaction, and aggregated to produce calcifying nodules in the ECM, leading to tendon calcification and stiffening. More importantly, apoV-releasing inhibition or macrophage deletion both successfully reversed HO development. Thus, we are the first to identify calcified apoVs from PROCR + fibroblasts as the initiating factor of HO, and might serve as the therapeutic target for inhibiting pathological calcification., (© 2024 The Authors. Journal of Extracellular Vesicles published by Wiley Periodicals LLC on behalf of International Society for Extracellular Vesicles.)