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Intervertebral disc degeneration (IDD) is the cause of low back pain (LBP), and recent research has suggested that inflammatory cytokines play a significant role in this process. Maslinic acid (MA), a natural compound found in olive plants (Olea europaea), has anti-inflammatory properties, but its potential for treating IDD is unclear. The current study aims to investigate the effects of MA on TNFα-induced IDD in vitro and in other in vivo models. Our findings suggest that MA ameliorates the imbalance of the extracellular matrix (ECM) and mitigates senescence by upregulating aggrecan and collagen II levels as well as downregulating MMP and ADAMTS levels in nucleus pulposus cells (NPCs). It can also impede the progression of IDD in rats. We further find that MA significantly affects the PI3K/AKT and NF-κB pathways in TNFα-induced NPCs determined by RNA-seq and experimental verification, while the AKT agonist Sc-79 eliminates these signaling cascades. Furthermore, molecular docking simulation shows that MA directly binds to PI3K. Dysfunction of the PI3K/AKT pathway and ECM metabolism has also been confirmed in clinical specimens of degenerated nucleus pulposus. This study demonstrates that MA may hold promise as a therapeutic agent for alleviating ECM metabolism disorders and senescence to treat IDD.

To study the effect of static pressure on the surface integrity of beryllium copper alloy during the ultrasonic rolling process, scanning electron microscope, stylus roughness tester, rockwell hardness tester, X-ray diffraction analyzer and metallographic microscope were used to measure and analyze the surface morphology, roughness, surface hardness, residual stress and microstructure of the before and after ultrasonic rolling specimens. The results indicate that the static pressure and the surface roughness show a nonlinear relationship in the range of test parameters. With the increase of static pressure, the surface roughness decreases first and then increases. Moreover, we can obtain better surface quality when the static pressure is 0.2 MPa～0.4 MPa. Work hardening and grain refinement of the material surface caused by the plastic strain generated during the ultrasonic rolling process are the main reasons for the increase in hardness. The surface hardness of the treated specimen can reach 43.3 HRC, which is 18.6% higher than that of the untreated specimen.The ultrasonic rolling treatment can transform the residual tensile stress on the surface of the material into residual compressive stress, which is of great significance for improving the surface mechanical properties of the material.

ADC12 aluminum alloy has been widely used in the aerospace, ship, and automotive fields because of its high specific strength, excellent die-casting performance, and wear resistance. Adhesion wear is the main wear mechanism of high-speed milling ADC12 aluminum alloy. The most important factor affecting adhesion wear is the tool–chip interface friction, which is directly manifested in the tool–chip interface temperature. Therefore, the temperature variation during the milling of aluminum alloy is analyzed using a temperature field model and infrared temperature measurement technology. Then, the tool wear morphology and the tool wear land width are observed using a scanning electron microscope. Finally, the tool wear mechanism considering the tool–chip interface temperature is discussed. The tool–chip interface temperature is related to the friction angle, tool–chip contact length, and friction force at the rake face, which increases first and then decreases as the cutting speed and feed rate increase. During the formation of the adhesive layer, the tool–chip interface temperature increases, the change rate of the cutting force and the tool wear rate increase, and adhesion, oxidation, and abrasive and delamination wear are generated on the tool surface. With the increase in temperature, the tool wear rate increases, the molten adhesive layer on the tool surface is accompanied by crack propagation, and adhesion wear, oxidation wear, and abrasive wear occur on the tool surface. [ABSTRACT FROM AUTHOR]

Graphene aerogels possess unique advantages for treating oil–water mixtures, but their fragile mechanical properties hinder further development, and their separation mechanisms remain unclear. Herein, a superhydrophobic silane-crosslinked graphene oxide/polyvinyl alcohol aerogel (Si-GPA) was prepared by directional freeze-drying of a graphene oxide/polyvinyl alcohol (GO/PVA) suspension and vapor-phase deposition of methyltriethoxysilane (MTES) for efficient on-demand oil–water separation, and its separation mechanism was revealed through computational fluid dynamics (CFD) simulations. With the binding of PVA polymer chains and the cross-linking of MTES monomers, the Si-GPA exhibits excellent anisotropy, radial superelasticity (over 50 000 cycles at 50% strain), and axial superstiffness (freezing direction) (more than 20 000 times its own weight), which are the best-known results to date. The Si-GPA utilizes its superelasticity to adsorb floating oil on the sea surface and oil droplets in oil-in-water emulsions, while employing its superstiffness to filter water-in-oil emulsions in pipelines for on-demand oil–water separation. More importantly, the Si-GPA overcomes the trade-off between flux and efficiency, enabling the separation of water-in-oil emulsions with water droplet sizes several times smaller than its pore size under gravity alone, and with ultra-high flux (4350 L m−2 h−2) and ultra-high purity (99.9%), 1–2 times higher than those of 2D superwetting separation membranes that require external pressure. Additionally, visualization analysis based on simulation modeling reveals the emulsion coalescence filtration mechanism of the Si-GPA. Therefore, mechanically robust superhydrophobic graphene aerogels have enormous potential in oil–water separation applications. [ABSTRACT FROM AUTHOR]