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Objectives: To evaluate whether MRI-based T stage (TMRI), [18F]FDG PET/CT-based N (NPET/CT), and M stage (MPET/CT) are superior in NPC patients' prognostic stratification based on long-term survival evidences, and whether TNM staging method involving TMRI + NPET/CT + MPET/CT could improve NPC patients' prognostic stratification. Methods: From April 2007 to December 2013, 1013 consecutive untreated NPC patients with complete imaging data were enrolled. All patients' initial stages were repeated based on (1) the NCCN guideline recommended "TMRI + NMRI + MPET/CT" ("MMP") staging method; (2) the traditional "TMRI + NMRI + Mconventional work-up (CWU)" ("MMC") staging method; (3) the single-step "TPET/CT + NPET/CT + MPET/CT" ("PPP") staging method; or (4) the "TMRI + NPET/CT + MPET/CT" ("MPP") staging method recommended in present research. Survival curve, ROC curve, and net reclassification improvement (NRI) analysis were used to evaluate the prognosis predicting ability of different staging methods. Results: [18F]FDG PET/CT performed worse on T stage (NRI = − 0.174, p < 0.001) but better on N (NRI = 0.135, p = 0.004) and M stage (NRI = 0.126, p = 0.001). The patients whose N stage upgraded by [18F]FDG PET/CT had worse survival (p = 0.011). The "TMRI + NPET/CT + MPET/CT" ("MPP") method performed better on survival prediction when compared with "MMP" (NRI = 0.079, p = 0.007), "MMC" (NRI = 0.190, p < 0.001), or "PPP" method (NRI = 0.107, p < 0.001). The "TMRI + NPET/CT + MPET/CT" ("MPP") method could reclassify patients' TNM stage to a more appropriate stage. The improvement is significant in patients with more than 2.5-years follow-up according to the time-dependent NRI values. Conclusions: The MRI is superior to [18F]FDG PET/CT in T stage, and [18F]FDG PET/CT is superior to CWU in N/M stage. The "TMRI + NPET/CT + MPET/CT" ("MPP") staging method could significantly improve NPC patients' long-term prognostic stratification. Clinical relevance statement: The present research provided long-term follow-up evidence for benefits of MRI and [18F]FDG PET/CT in TNM staging for nasopharyngeal carcinoma, and proposes a new imaging procedure for TNM staging incorporating MRI-based T stage and [18F]FDG PET/CT-based N and M stage, which significantly improves long-term prognostic stratification for patients with NPC. Key Points: • The long-term follow-up evidence of a large-scale cohort was provided to evaluate the advantages of MRI, [18F]FDG PET/CT, and CWU in the TNM staging of nasopharyngeal carcinoma. • A new imaging procedure for TNM stage of nasopharyngeal carcinoma was proposed. [ABSTRACT FROM AUTHOR]

Nano-silica (SiO2) has been widely used to fill rubbers (crosslinked) and usual polyolefin elastomers (POEs). SiO2 filled POE with crystalline structure can also be crosslinked. Crystallization, structure, and mechanical properties of crosslinked POE/SiO2 composites can be affected by SiO2. In this paper, crosslinked POE/SiO2 composites were obtained through two different methods: dynamic crosslinking in molten state and static crosslinking. For the non-crosslinked and static crosslinked composites, SiO2 had a more significant effect on the nucleation in non-crosslinked POE than in static crosslinked POE. For the dynamic crosslinked composite, SiO2 and crosslinking points hindered the mobility of POE chains and suppressed the POE crystallization, resulting in smaller and fewer crystals. Dynamic mechanical analysis showed that the SiO2 and POE were compatible, as evidenced by the lower tan(δ) value in SiO2-filled samples. The latter was more consistent with the higher tensile strength and elongation at break for the non-crosslinked and static crosslinked composites than for the non-filled samples. However, the dynamic crosslinked composite exhibited the worst elongation at break, resulting from the lowest number of crystals and shortened molecular chains due to the shearing that occurred during crosslinking process. The SiO2 had no observable effect on the permanent deformation of samples. [ABSTRACT FROM AUTHOR]