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Tumorous bone defects present significant challenges for surgical bio‐reconstruction due to the dual pathological conditions of residual tumor presence and extensive bone loss following excision surgery. To address this challenge, a "thermal switch" smart bone scaffold based on the silicene nanosheet‐modified decalcified bone matrix (SNS@DBM) is developed by leveraging the natural affinity between collagen and silicene, which is elucidated by molecular dynamics simulations. Benefitting from its exceptional photothermal ability, biodegradability, and bioactivity, the SNS@DBM "thermal switch" provides an integrated postoperative sequential thermotherapy for tumorous bone loss by exerting three levels of photothermal stimulation (i.e., strong, moderate, and nonstimulation). During the different phases of postoperative bioconstruction, the SNS@DBM scaffold realizes simultaneous residual tumor ablation, tumor recurrence prevention, and bone tissue regeneration. These biological effects are verified in the tumor‐bearing nude mice of patient‐derived tissue xenografts and critical cranium defect rats. Mechanism research prompts moderate heat stimulus generated by and coordinating with SNSs can upregulate osteogenic genes, promote macrophages M2 polarization, and intensify angiogenesis of H‐type vessels. This study introduces a versatile approach to the management of tumorous bone defects. [ABSTRACT FROM AUTHOR]

Marine microalgae, Platymonas helgolondica var. tsingtaoensis , were used as experimental subjects to study the acute toxic effects of graphene oxide (GO) and dibutyl phthalate (DBP), both individually and together. The growth of algae cells, production of photosynthetic pigments, cell permeability, and oxidative stress were investigated. The effects of GO on the algal toxicity of DBP were evaluated. The results showed that low concentrations of GO (0.1-10 mg·L -1 ) had no significant effect on algae density and chlorophyll production of Platymonas helgolondica var. tsingtaoensis ( P <0.05). However, the algae cell permeability increased significantly with GO concentration ( P <0.05) and reached 2.2 times that of the control group at 10 mg·L -1 . The EC 50, 96 h value of DBP for Platymonas helgolondica var. tsingtaoensis was (11.14±0. 80) mg·L -1 , which, in terms of toxicity, was much higher than that of GO (EC 50, 96 h >100 mg·L -1 ). At a GO concentration of 1 mg·L -1 , the EC 50, 96 h value of DBP decreased to (4.93±2.14) mg·L -1 , showing that low concentrations of GO enhanced the algae toxicity of DBP. When 1 mg·L -1 of GO was added, low concentrations of DBP (0.1-2 mg·L -1 ) did not have any significant effect on algae density, chlorophyll production, cell permeability, ROS, and SOD. However, the inhibitory effects of high concentrations of DPB (4 mg·L -1 ) on algae density and chlorophyll production were enhanced by GO, thereby increasing the average ROS and SOD in algae cells by 21% and 7%, respectively. SEM images showed that GO was the primary factor responsible for increasing the coverage and packing of, and the aggregation effect on, algae cells, which could be the reasons for the increased toxicity of DBP. The results of our study can provide data to reveal the risk of novel carbon nanomaterial pollutants to marine organisms.