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Single‐emitter luminescence is attractive for various applications, including single‐molecular biology, super‐resolution optical imaging, and single‐photon sources. Optical trapping as a particle positioning method is promising for enhancing luminescence by a precise matching of the nanoemitter to the sub‐wavelength mode volume of the photonic structure. Simultaneously satisfying the requirement of both luminescence and trapping enhancement, however, is challenging. Here, stable optical trapping and the in situ excitation of highly bright photoluminescence of a single up‐conversion nanoparticle (UCNP) are demonstrated. A quad‐nanohole structure with two bright‐field modes for enhanced excitation and emission of the UCNP, as well as a dark‐field mode for enhanced optical trapping is designed. It is experimentally demonstrated that the photoluminescence of the UCNP optically trapped in the quad‐nanohole is enhanced by a factor of 87 (as compared to a UCNP trapped in the single nanohole), and this enhancement factor surpasses that from a bowtie nanohole—one of the "gold standards" for local field enhancement. This work provides a route to assemble super‐bright single‐emitter luminescence by optical trapping. [ABSTRACT FROM AUTHOR]

Background: Coronary computed tomography (CT) angiography imaging is useful for the preprocedural evaluation of chronic total occlusion (CTO). However, the predictive value of CT radiomics model for successful percutaneous coronary intervention (PCI) has not been studied. We aimed to develop and validate a CT radiomics model for predicting PCI success of CTOs. Methods: In this retrospective study, a radiomics-based model for predicting PCI success was developed on the training and internal validation sets of 202 and 98 patients with CTO, collected from 1 tertiary hospital. The proposed model was validated on an external test set of 75 CTO patients enrolled from another tertiary hospital. CT radiomics features of each CTO lesion were manually labeled and extracted. Other anatomical parameters, including occlusion length, entry morphology, tortuosity, and calcification burden, were also measured. Fifteen radiomics features, 2 quantitative plaque features, and CT-derived Multicenter CTO Registry of Japan score were used to train different models. The predictive values of each model were evaluated for predicting revascularization success. Results: In the external test set, 75 patients (60 men; 65 years [58.5, 71.5]) with 83 CTO lesions were assessed. Occlusion length was shorter (13.00 mm versus 29.30 mm, P =0.007) in PCI success group whereas the presence of tortuous course was more commonly presented in PCI failure group (1.49% versus 25.00%, P =0.004). The radiomics score was significantly smaller in PCI success group (0.10 versus 0.55, P <0.001). The area under the curve of CT radiomics-based model was significantly higher than that of CT-derived Multicenter CTO Registry of Japan score for predicting PCI success (area under the curve=0.920 versus 0.752, P =0.008). The proposed radiomics model accurately identified 89.16% (74/83) CTO lesions with procedure success. Conclusions: CT radiomics-based model outperformed CT-derived Multicenter CTO Registry of Japan score for predicting PCI success. The proposed model is more accurate than the conventional anatomical parameters to identify CTO lesions with PCI success. [ABSTRACT FROM AUTHOR]