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The rutting and cracking distresses of asphalt pavement severely affect its service life. Enhancing the visco-toughness and mechanical properties of asphalt by using graphene may improve the durability of asphalt pavement. To enhance the visco-toughness and mechanical properties of asphalt, dimethyl sulfoxide pretreated graphene (DG) was utilized to modify asphalt, and its effects on the microstructure and mechanical properties of asphalt were investigated using X-ray diffraction, Charpy impact, bending fracture, and other tests, thus revealing DG's enhancement mechanism Results indicate that the layer spacing of DG is increased, indicating that intercalation structures between asphalt and DG are formed. When the crack tip meets the intercalated DG, the partial fracture energy is absorbed, enhancing the asphalt's tenacity and hindering crack propagation. The energy absorption capacity and impact visco-toughness are also enhanced. Finally, the DG intercalation structure disperses the primary crack propagation by producing many microcracks, so that the brittle fracture is reduced at low temperatures. DG shows much promise as an application for improving the mechanical properties of asphalt. [ABSTRACT FROM AUTHOR]

Therapeutic benefits of immunotherapy are restricted by cancer immune-resistance mechanisms. Rediocide-A (Red-A), a natural product extracted from Traditional Chinese Medicine, is a promising agent to battle against cancer which acts as an immune checkpoint inhibitor. To investigate the effect of Red-A on NK-cell tumouricidal activity. NK cells were co-cultured with A549 or H1299 cells and treated with 10 or 100 nM Red-A for 24 h. Cells treated with 0.1% dimethyl sulphoxide (DMSO) was employed as vehicle control. NK cell-mediated cytotoxicity was detected by biophotonic cytotoxicity and impedance assay. Degranulation, granzyme B, NK cell-tumour cell conjugates and ligands profiling were detected by flow cytometry. Interferon-γ (IFN- γ) production was assessed by enzyme-linked immunosorbent assay (ELISA). Red-A increased NK cell-mediated lysis of A549 cells by 3.58-fold (21.86% vs. 78.27%) and H1299 cells by 1.26-fold (59.18% vs. 74.78%), compared to vehicle control. Granzyme B level was increased by 48.01% (A549 cells) and 53.26% (H1299 cells) after 100 nM Red-A treatment. INF-γ level was increased by 3.23-fold (A549 cells) and 6.77-fold (H1299 cells) after 100 nM Red-A treatment. Red-A treatment down-regulated the expression level of CD155 by 14.41% and 11.66% in A549 cells and H1299 cells, respectively, leading to the blockade of tumour immuno-resistance to NK cells. Red-A overcomes immuno-resistance of NSCLCs to NK cells by down-regulating CD155 expression, which shows the possibility of developing checkpoint inhibitors targeting TIGIT/CD155 signalling to overcome immuno-resistance of cancer cells. [ABSTRACT FROM AUTHOR]

• The graphene pretreated by DMSO is more evenly dispersed in bitumen than that by NMP; • The DG effectively inhibits the formation of sulfoxide groups during the bituminous aging; • The intercalation structures formed between DG and asphalt inhibit the bituminous aging; • The DG modified bitumen has a weaker absorption and stronger reflection capacity to UV; • A method is developed to prepare DG modified bitumen with better anti-aging performance. To increase the graphene dispersity in bitumen, the dispersant solvent dimethyl sulfoxide (DMSO) pretreated graphene (DG) and N-methylpyrrolidone (NMP) pretreated graphene (NG) were first prepared, and were used as modifiers to prepare modified bitumen, respectively. After a comprehensive evaluation, it is found that DG is more uniformly dispersed in bitumen. DG modified bitumen shows better mechanical properties, and is selected to assess the impacts of DG contents on bituminous different properties after aging. Results indicate that DG effectively inhibits the formation of sulfoxide groups in the aging process of modified bitumen. The intercalation structure between DG and bitumen reduces the entry amount of oxygen, and slows down the transformation progress from micromolecular to macromolecular components in bitumen. Additionally, the modified bitumen with the DG content of 0.4 wt% has a weaker ultraviolet absorption ability and stronger ultraviolet reflection capacity, increasing the aging resistance of modified bitumen. Moreover, the ultraviolet absorption capacity of DG modified bitumen is decreased as the aging degree is increased. The DG content of 0.4 wt% is proposed to prepare modified bitumen, improving mechanical and anti-aging properties of bitumen. [ABSTRACT FROM AUTHOR]