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Objective: The objective of this study is to segment creeping fat and intestinal wall on computed tomography enterography (CTE) and develop a radiomic model to predict 1-year surgery risk in patients with Crohn's disease., Methods: This retrospective study included 135 Crohn's disease patients who underwent CTE between January and December 2021 (training cohort) and 69 patients between January and June 2022 (test cohort). A total of 1874 radiomic features were extracted from the intestinal wall and creeping fat respectively on the venous phase CTE images, and radiomic models were constructed based on the selected features using the Boruta and extreme gradient boosting algorithms. The combined models were established by integrating clinical predictors and radiomic models. The receiver operating characteristic curve, calibration curve, and decision curve analyses were used to compare the predictive performance of models., Results: In the training and test cohorts, the area under the curve (AUC) values of the creeping fat radiomic model for surgery risk stratification were 0.916 and 0.822, respectively, similar to the intestinal model with AUC values of 0.889 and 0.822. Moreover, the combined radiomic model was superior to the single models, showing good discrimination with the highest AUC values (training cohort: 0.963; test cohort: 0.882). Addition of clinical predictors to the radiomic models failed to significantly improve the diagnostic ability., Conclusion: The CTE-based creeping fat radiomic model provided additional information to the intestinal radiomic model, and their combined radiomic model enables accurate surgery risk prediction of Crohn's disease patients within 1 year of CTE., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

In this study, we investigated the utility of native T 1 mapping in differentiating between various grades of fibrosis and compared its diagnostic accuracy to magnetization transfer imaging (MTI) in a rat model of CD. Bowel specimens (64) from 46 CD model rats undergoing native T 1 mapping and MTI were enrolled. The longitudinal relaxation time ( T 1 value) and normalized magnetization transfer ratio (MTR) were compared between none-to-mild and moderate-to-severe fibrotic bowel walls confirmed by pathological assessments. The results showed that the correlation between the T 1 value and fibrosis ( r = 0.438, p < 0.001) was lower than that between the normalized MTR and fibrosis ( r = 0.623, p < 0.001). Overall, the T 1 values ( t = -3.066, p = 0.004) and normalized MTRs ( z = 0.081, p < 0.001) in none-to-mild fibrotic bowel walls were lower than those in moderate-to-severe fibrotic bowel walls. The area under the curve (AUC) of the T 1 value (AUC = 0.716, p = 0.004) was significantly lower than that of the normalized MTR (AUC = 0.881, p < 0.001) in differentiating moderate-to-severe fibrosis from none-to-mild fibrosis ( z = -2.037, p = 0.042). Our results support the view that the T 1 value could be a promising imaging biomarker in grading the fibrosis severity of CD. However, the diagnostic performance of native T 1 mapping was not superior to MTI.

Graphene-nickel (G-Ni) composites were in situ fabricated by a powder metallurgy method. The effects of graphene content on the tribological behavior of G-Ni composites were investigated. The tribochemistry and structural evolution of graphene were analyzed by X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy to understand the lubricating role of graphene in the G-Ni composite. The results show that graphene protects the nickel matrix from severe oxidation at the expense of its oxidation during sliding friction. Graphene on the friction interface transforms from a structure with less defects to a disordered amorphous structure. Polymeric segments are also generated by the tribochemical reactions of graphene. The formation of the tribofilms containing amorphous carbon and polymers is responsible for the self-lubricating behavior of the G-Ni composites., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)