RESUMO
Background: The parietal pleural adhesion/invasion of lung cancer can contribute substantially to poor prognosis and difficulty in surgery. The value of ultrasound in evaluating the parietal pleural adhesion or invasion (pleural adhesion/invasion) of lung cancer remains uncertain. This study investigated the value of B-mode ultrasound and contrast-enhanced ultrasound (CEUS) in diagnosing parietal pleural adhesion/invasion of subpleural lung cancer. Methods: The study animals included 40 male New Zealand white rabbits. A rabbit subpleural lung cancer model was constructed by injecting VX2 tumor tissue under ultrasound guidance. In the 1-3 weeks after subpleural lesion formation, parietal pleural adhesion/invasion of the largest subpleural lesion was evaluated with B-mode ultrasound and CEUS by two sonographers. The parietal pleural adhesion/invasion was also determined using the gold standard method of findings from anatomical and pathological examination. Results: Ultimately, 34 rabbits were subjected to complete ultrasonic evaluation. There were 20 and 14 cases with and without parietal pleural adhesion/invasion, respectively, as confirmed by anatomical and pathological evaluations. The diagnostic sensitivity, specificity, and accuracy of sonographer 1 using B-mode ultrasound were 50.0% [95% confidence interval (CI): 26.0-74.0%], 100%, and 70.6% (95% CI: 54.5-86.7%), respectively; for CEUS, they were 90.0% (95% CI: 75.6-100.0%), 100.0%, and 94.1% (95% CI: 85.8-100.0%), respectively. The diagnostic sensitivity, specificity, and accuracy of sonographer 2 using B-mode ultrasound were 45.0% (95% CI: 21.1-68.9%), 92.9% (95% CI: 77.5-100.0%), and 64.7% (95% CI: 47.8-81.6%), respectively; for CEUS, they were 85.0% (95% CI: 67.9-100.0%), 100.0%, and 91.2% (95% CI: 81.1-100.0%), respectively. The diagnostic accuracy of sonographer 1 was higher with CEUS than with B-mode ultrasound, but not significantly so (94.1% vs. 70.6%; P=0.08). The diagnostic accuracy of sonographer 2 was significantly higher with CEUS than with B-mode ultrasound (91.2% vs. 64.7%; P=0.03). The interrater reliability was higher for CEUS than for B-mode ultrasound (κ=0.941 vs. κ =0.717). Conclusions: Based on an animal model, B-mode ultrasound and CEUS both exhibited good diagnostic efficacy and interrater reliability in evaluating parietal pleural adhesion/invasion of subpleural lung cancer although CEUS outperformed B-mode ultrasound for both measures.
RESUMO
All-inorganic perovskites (CsPbX3) with the merits of high stability and remarkable optical gain property are attractive for achieving on-chip coherent light sources. Unfortunately, traditional solution-processed CsPbX3 films suffer from inevitable poor surface integrity and pinhole defects, severely hindering their optical properties. Here, from the perspective of precursor solution chemistry, we use an ionic liquid solvent methylammonium acetate (MAAc) to fabricate compact, pinhole-free, and smooth CsPbX3 thin films in a one-step air process without antisolvent treatment. Optically pumped amplified spontaneous emission (ASE) with a straightforward visible spectral tunability (418-725 nm) is achieved under both nanosecond and femtosecond laser excitation. For the representative CsPbBr3 films, the threshold reaches down to 11.4 µJ cm-2 under nanosecond laser pumping, which is comparable to the value under one-photon femtosecond pumping. The long gain lifetime up to 258.2 ps is revealed by transient absorption spectroscopy. Most importantly, the films show excellent optical stability and humidity stability with no obvious degradation under the pulsed laser irradiation for more than 210 min, stable ASE output under 95% high humidity, and conspicuous ASE after 1000 h of storage in air condition without encapsulation. These results demonstrate that the method of fabricating inorganic perovskite films with an ionic liquid solvent is promising in developing high-performance full-color visible lasers.
RESUMO
The poor stability, in particular with respect to temperature, moisture, and light exposure, remains a ubiquitous impediment virtually for metal halide perovskite materials and devices in their future practical application. Herein, from the perspective of precursor solution chemistry, ionic liquid solvent methylammonium acetate (MAAc) is introduced to prepare high-quality MAPbBr3 perovskite thin films in a one-step air-processing process without anti-solvent treatment. Due to formation of pinhole-free, uniform, and compact MAPbBr3 perovskite film, excellent amplified spontaneous emission (ASE) with high emission efficiency and low threshold is obtained under nanosecond laser. Furthermore, the prepared MAPbBr3 perovskite exhibits excellent two-photon induced ASE with a low threshold of 100 µJ cm-2 under 800 nm femtosecond laser excitation. More importantly, in comparison with the traditional MAPbBr3 films prepared with N,N-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO), the MAPbBr3 film prepared with MAAc shows excellent optical stability: no signs of degradation under more than 2 h pulsed laser excitation, stable ASE emission spectra under the humidity of 95% and ASE spectra can be stimulated when films are kept in air for more than 6000 h without encapsulation.
