Graphene-based materials (GMs) have great application prospects in bone tissue engineering due to their osteoinductive ability and antimicrobial activity. GMs induce osteogenic differentiation through several mechanisms and pathways in bone tissue engineering. First of all, the surface and high hardness of the porous folds of graphene or graphene oxide (GO) can generate mechanical stimulation to initiate a cascade of reactions that promote osteogenic differentiation without any chemical inducers. In addition, change of the extracellular matrix (ECM), regulation of macrophage polarization, the oncostatin M (OSM) signaling pathway, the MAPK signaling pathway, the BMP signaling pathway, the Wnt/β-catenin signaling pathway, and other pathways are involved in GMs' regulation of osteogenesis. In bone tissue engineering, GMs prevent the formation of microbial biofilms mainly through preventing microbial adhesion and killing them. The former is mainly achieved by reducing surface free energy (SFE) and increasing hydrophobicity. The latter mainly includes oxidative stress and photothermal/photodynamic effects.Graphene and its derivatives (GDs) are mainly combined with bioactive ceramic materials, metal materials and macromolecular polymers to play an antimicrobial effect in bone tissue engineering. Concentration, number of layers, and type of GDs often affect the antimicrobial activity of GMs. In this paper, we reviewed relevant osteoinductive and antimicrobial mechanisms of GMs and their applications in bone tissue engineering.

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The stratums along the Beijing-Shanghai high-speed railway are composed mainly with soft soil. The foundation of roadbed were strengthened in hope of reducing differential and total settlement. Ram-compacted piles are mentioned in this paper, as an example of strengthening methods. Using joint test method combining liquid level settlement gauges and single point settlement gauges, total settlements and compressions at different depths were measured. Field test results showed that：1. The settlements were significantly reduced. 2. The settlement of the basement with cap at the middle of roadbed mainly appeared during filling stage, and that without cap indicated a 30-day-stablisation during preloading stage. 3. The up thorn can be decreased by pile cap. 4. The largest settlement was found at roadbed center, whereas the smallest occurred at embankment toe. Ram-compacted piles successfully reduced settlement of roadbed, offering reference value to high-speed railway design.

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: Posttraumatic chronic maxillary sinusitis deleteriously affects the life quality of patients with recurrent episodes and related discomfort. However, few studies have been performed to investigate the prevalence of chronic maxillary sinusitis after surgery of mid-facial fracture and related risk factors. The early prevention and cure of posttraumatic chronic maxillary sinusitis have received little attention. This study aimed to investigate the prevalence of chronic maxillary sinusitis after surgery for mid-facial fracture and to identify related risk factors. The authors retrospectively collected the medical history, radiographic examination, and clinical examination of patients with mid-facial fracture (experimental group) and patients with mandibular cyst (control group) in our department between January 2015 and December 2020. A total of 298 patients (416 maxillary sinuses) in the experimental group and 172 patients (344 maxillary sinuses) in the control group were included for analyses. The prevalence of chronic maxillary sinusitis in the experimental group and control group were, respectively, 9.14% and 2.04% (P < 0.05). History of sinusitis/rhinitis (odds ratio = 63.70, P = 0.000) was an independent risk factor for posttraumatic chronic maxillary sinusitis. In conclusion, these findings showed that the prevalence of chronic maxillary sinusitis after surgery for midfacial fracture was significantly higher than that in the control group and long-term follow-up may be beneficial for these patients. Moreover, patients with a history of sinusitis/rhinitis should be informed of the increased risk.