ABSTRACT
To promote resourceful utilization of argon oxygen decarburization (AOD) slag, this research developed a new three-ash stabilized recycled aggregate with AOD slag, cement, fly ash (FA), and recycled aggregate (RA) as raw materials. The AOD slag was adopted as an equal mass replacement for fly ash. The application of this aggregate in a road base layer was investigated in terms of its mechanical properties and mechanistic analysis. First, based on a cement: FA ratio of 1:4, 20 sets of mixed proportion schemes were designed for four kinds of cement dosage and AOD slag replacement rates (R/%). Through compaction tests and the 7-day unconfined compressive strength test, it was found that a 3% cement dosage met the engineering requirements. Then, the unconfined compressive strength test, indirect tensile strength test, compressive rebound modulus test, and expansion rate test were carried out at different age thresholds. The results showed that the mixture's strength, modulus, and expansion rate increased initially and then stabilized with age, while the strength and modulus initially increased and then decreased with increasing R. Secondly, based on X-ray diffraction (XRD) and scanning electron microscopy (SEM) used to analyze the mechanism, it was found that the strength, modulus, and expansion rate of the new material can be promoted by blending AOD slag, due to its ability to fully stimulate the hydration reaction and pozzolanic reaction of the binder. Finally, based on the strength and modulus results, R = 3% was identified as the optimal ratio, which provides a reference point for the effective application of AOD slag and RA in road base materials.
ABSTRACT
Background: Wenhua Juanbi Recipe (WJR) is widely used for the treatment of rheumatoid arthritis (RA) in China. However, its mechanism of action remains unclear. This study was designed to investigate the potential therapeutic effects of WJR on the proliferation and apoptosis of synovial fibroblasts in RA and its efficacy in inhibiting miRNA-146a-mediated cellular autophagy. Methods: A collagen-induced arthritis (CIA) Wistar rat model was established. The model rats were administered WJR or methotrexate (MTX) to assess the therapeutic effect of the drugs. The chemical components of WJR were analyzed using UPLC-Q/TOF-MS. Histological changes; miRNA-146a, ATG5, ATG7, ATG12, Beclin1, LC3II, Bax, and Bcl2 expression; synovial apoptosis; and cellular proliferation were assessed. Primary synovial fibroblasts (FLS) were cultured in vitro using tissue block and transfected with miRNA-146a; an autophagy inducer was added to FLS, inhibiting the PI3K/AKT/mTOR pathway. FLS were cocultured with WJR-containing serum to observe the effects of miRNA-146a-mediated autophagy via the PI3K/AKT/mTOR pathway on CIA-affected rats. Results: Forty and thirty-one compounds were identified in WJR in the positive and negative ion modes, respectively. WJR significantly reduced toe swelling, arthritis scores, and expression of miRNA-146a and autophagy genes (ATG5, ATG7, ATG12, Beclin1, LC32, and Bcl2). Moreover, Bax expression, apoptosis, and attenuated proliferation were observed in rats. WJR could, therefore, regulate autophagy by influencing the miRNA-146a-mediated PI3K/AKT/mTOR pathway, which induces apoptosis and proliferation of FLS. Conclusion: WJR can inhibit autophagy, apoptosis, and proliferation in a CIA rat model by inhibiting the miRNA-146a-mediated PI3K/AKT/mTOR pathway.
