ABSTRACT
Lateral growth of thin films is crucial for organic electronic devices, such as field-effect transistors. Here, we report a strategy to improve the lateral growth of pentacene films using rubrene as a surfactant-like additive. Atomic force microscopy (AFM) images confirm the enhanced lateral growth with the presence of rubrene, resulting in smooth and enlarged molecule domains in the films in comparison to those without rubrene. Molecular dynamics simulations are conducted to explore the interlayer diffusion of pentacene molecules during the growth. With the rubrene molecules as surfactant-like additives, mean square displacement (MSD) analysis shows that the pentacene molecules have a descending diffusion coefficient of 2.0 × 10-5 cm2 s-1, which is greater than the ascending diffusion coefficient of 1.6 × 10-5 cm2 s-1. The more descending molecules lead to an enhanced lateral growth of pentacene films, which is in good agreement with the experiments. As a result, the pentacene films grown with rubrene exhibit a rapid increase in carrier mobility over thickness due to the well-connected domains resulting from enhanced lateral growth. This finding will provide a new strategy to modulate the morphology of organic films for high-performance devices.
ABSTRACT
Objective: To investigate the effect of dual fluorescence imaging in identifying central lymph nodes and parathyroid glands during thyroid cancer surgery. Methods: This study was a cross-sectional study. Patients who underwent surgery for papillary thyroid cancer (PTC) at the Department of Head and Neck Surgery, Beijing Tongren Hospital, Capital Medical University between January 2022 and September 2023 were included. All patients underwent thyroid lobectomy or total resection, and central lymph node dissection was performed at the same time. During the operation, tracing injection of mitoxantrone hydrochloride and 785 nm and 660 nm dual fluorescence imaging technique were used to measure the fluorescence intensity (FI) of parathyroid glands, central lymph nodes and background. After correcting to obtain the standardized FI, the paired t-test was used to compare the standardized FI of the parathyroid glands and central lymph nodes, and the Spearman's rank correlation analysis was used to analyze the relationship between the standardized FI and various clinical indicators. Results: The study included 30 patients (8 males and 22 females), with a mean age of (41.8±10.4) years. A total of 76 parathyroid glands and 234 central lymph nodes were identified under dual fluorescence imaging, and the standardized FI of parathyroid glands was less than that of central lymph nodes (44.7±16.8 vs 99.5±28.4, P<0.001). The visualization rate, false rate and miscut rate of parathyroid glands under 785 nm wavelength excitation light were 98.7% (76/77), 0 (0/77) and 1.3% (1/77), respectively (one case with no visualization and miscutting parathyroid gland was the encapsulated type). The visualization rate of central lymph nodes under 660 nm wavelength excitation light was 98.7% (234/237). There was no significant correlation between FI and clinical indicators such as gender, age, height, weight, body mass index, preoperative thyroid stimulating hormone, thyroglobulin antibody, thyroid microsomal antibody, serum calcium, parathyroid hormone level and surgical procedure (all P>0.05). Conclusion: Dual fluorescence imaging of central lymph nodes and parathyroid glands can improve the ability to identify parathyroid gland while assisting central lymph node dissection.