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Although 3D printing technology has been widely applied in fabrication of polymer composite, yet, it still exhibits low mechanical performance, restricting its application in structural materials. Herein, a new 3D printing polymer composite composed of carbon fiber and polyamide12 (PA12) is fabricated and subsequently treated by microwave treatment. It is found that the tensile strength and modulus of 3D printing CF/PA12 composite with microwave treatment are improved by 23.8% and 10.2% compared with the original specimen, respectively. Moreover, a new mechanism of mechanical reinforcement is investigated and proposed by nanoindentation and 3D X‐ray computed tomography. The work does not only confirm formation of 3D printing CF/PA12 composite with good mechanical properties, but also proposes a new mechanism of microwave treatment effect on 3D printing polymer composite based on carbon fiber. Highlights: A new 3D printing CF/PA12 composite based on microwave treatment is developed.The 3D printing composite exhibits good mechanical properties.A new mechanism of mechanical reinforcement is proposed. [ABSTRACT FROM AUTHOR]

Purpose: Microvascular invasion (MVI) is a critical factor in predicting the recurrence and prognosis of hepatocellular carcinoma (HCC) after liver transplantation (LT). However, there is a lack of reliable preoperative predictors for MVI. The purpose of this study is to evaluate the potential of an 18F-FDG PET/CT-based nomogram in predicting MVI before LT for HCC. Methods: 83 HCC patients who obtained 18F-FDG PET/CT before LT were included in this retrospective research. To determine the parameters connected to MVI and to create a nomogram for MVI prediction, respectively, Logistic and Cox regression models were applied. Analyses of the calibration curve and receiver operating characteristic (ROC) curves were used to assess the model's capability to differentiate between clinical factors and metabolic data from PET/CT images. Results: Among the 83 patients analyzed, 41% were diagnosed with histologic MVI. Multivariate logistic regression analysis revealed that Child–Pugh stage, alpha-fetoprotein, number of tumors, CT Dmax, and Tumor-to-normal liver uptake ratio (TLR) were significant predictors of MVI. A nomogram was constructed using these predictors, which demonstrated strong calibration with a close agreement between predicted and actual MVI probabilities. The nomogram also showed excellent differentiation with an AUC of 0.965 (95% CI 0.925–1.000). Conclusion: The nomogram based on 18F-FDG PET/CT metabolic characteristics is a reliable preoperative imaging biomarker for predicting MVI in HCC patients before undergoing LT. It has demonstrated excellent efficacy and high clinical applicability. [ABSTRACT FROM AUTHOR]

Owing to their attractive optical and chiroptical properties, chiral metal halide perovskites have received increasing attention, with potential applications ranging from photonics and optoelectronics to spintronics. Metal halide perovskite nanocrystals with either intrinsic or extrinsic (e.g., chiral ligand‐induced) chirality have been reported recently, and the interplay between these two types of chirality has yet to be addressed. Herein, the inversion and tuning of excitonic optical activity is reported in intrinsically chiral perovskite nanoplatelets, originating from interactions between their structural chirality (due to the spontaneously formed screw dislocations in the crystalline lattice) and the surface enantiomeric (R/S) chiral ligands R/S‐phenylethylammonium bromide. Through post‐preparative exposure of the perovskite nanoplatelets to these R/S ligands of varied contents, either chiral ligand‐induced intrinsic chirality inversion or negative and positive Cotton effects induced by the ligands via electronic coupling between the ligand and the nanoplatelets are identified. These findings deepen understanding of the modulation of excitonic optical activity in chiral perovskites and can guide the rational design and synthesis of novel chiral materials. [ABSTRACT FROM AUTHOR]

Despite the remarkable luminescent properties and temperature sensing capabilities of lanthanide materials, their photothermal effect in practical temperature measurement systems presents a major challenge to sensing reliability. Herein, taking Pr3+ as a typical exemplar, the influence of excitation wavelength and excitation approach on temperature sensing is systematically examined. The pulsed laser excitation method is identified as an efficient tactic to restrain the self‐heating of luminescence materials. In accordance with this principle, it is discovered that diverse excitation wavelengths give rise to alterations in the internal energy transport channels and further impact the temperature sensing performance. The 980 nm pulsed laser can result in the non‐thermal coupling occupying states of 3P0/3P1, which are recognized as thermal coupling energy levels in the conventional concept, and yield a relative sensitivity (Sr) performance more than three times superior to that of down‐shifting‐based sensing. The work provides a comprehensive analytical solution for achieving highly sensitive and stable temperature sensing based on excitation wavelength and working mode strategies. [ABSTRACT FROM AUTHOR]