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Crystallizationof materials has attracted research interest fora long time, and its mechanisms in three-dimensional materials havebeen well studied. However, crystallization of two-dimensional (2D)materials is yet to be challenged. Clarifying the dynamics underlyinggrowth of 2D materials will provide the insight for the potentialroute to synthesize large and highly crystallized 2D domains withlow defects. Here, we present the growth dynamics and recrystallizationof 2D material graphene under a mobile hot-wire assisted chemicalvapor deposition (MHW-CVD) system. Under local but sequential heatingby MHW-CVD system, the initial nucleation of nanocrystalline graphenes,which was not extended into the growth stage due to the insufficientthermal energy, took a recrystallization and converted into a grandsingle crystal domain. During this process, the stitching-like healingof graphene was also observed. The local but sequential endowing thermalenergy to nanocrystalline graphenes enabled us to simultaneously revealthe recrystallization and healing dynamics in graphene growth, whichsuggests an alternative route to synthesize a highly crystalline andlarge domain size graphene. Also, this recrystallization and healingof 2D nanocrystalline graphenes offers an interesting insight on thegrowth mechanism of 2D materials. [ABSTRACT FROM AUTHOR]

This report presents a unique case of Caplan syndrome that mimicked accelerated progressive massive fibrosis. The patient, a former coal miner, had been diagnosed with coal worker's pneumoconiosis 15 years prior and had been treated for rheumatoid arthritis for over 20 years. Accelerated progressive massive fibrosis and the development of multiple nodules with cavitation in the basal lungs were subsequently observed on serial CT scans. Here, the CT manifestations of Caplan syndrome are highlighted in a case in which Caplan syndrome mimicked accelerated progressive massive fibrosis., Competing Interests: Conflicts of Interest: The authors have no potential conflicts of interest to disclose., (Copyrights © 2024 The Korean Society of Radiology.)

Purpose: This multicenter prospective study aimed to evaluate the quality and diagnostic effectiveness of cerebral angiography images obtained using low-concentration iodinated contrast agents (iohexol 240 mgI/mL, iopamidol 250 mgI/mL, and iodixanol 270 mgI/mL) and to assess the safety thereof. The study addresses the need for safer contrast agent alternatives without compromising the diagnostic quality of identifying cerebrovascular disease., Materials and Methods: Conducted in 5 medical centers in South Korea, we enrolled patients aged 19 years or older who were referred for diagnostic cerebral angiography under non-emergency conditions, excluding those with specific health conditions and sensitivities. The study design included a prospective, observational approach with a 1-way analysis of variance (ANOVA) for sample size calculation, aiming for a total sample of 231 participants for adequate power. Image quality was evaluated using a 4-level scale by 2 independent, blinded radiologists, and adverse reactions were monitored both immediately and up to 7 days post-procedure. Statistical analysis involved 1-way ANOVA and Kruskal-Wallis tests to assess the image quality and safety profiles of the contrast agents., Results: Among 266 patients screened, 243 were included in the final analysis. The evaluation revealed no statistically significant differences in image quality among the 3 types of low-concentration contrast agents. Adverse events were observed in 28.8% of patients, with 27.2% experiencing acute reactions, primarily mild reactions, and 3.3% experiencing delayed reactions. The overall safety profile showed no significant changes in vital signs or electrocardiogram readings before and after contrast agent injection., Conclusion: Using low-concentration iodinated contrast agents for cerebral angiography provides image quality comparable to that of conventional high-concentration agents, with no significant increase in adverse events, suggesting a safer alternative for patients.

It has been challenging to synthesize p-type SnO x (1 < x < 2) and engineer the electrical properties such as carrier density and mobility due to the narrow processing window and the localized oxygen 2p orbitals near the valence band. Herein, we report on the multifunctional encapsulation of p-SnO x to limit the surface adsorption of oxygen and selectively permeate hydrogen into the p-SnO x channel for thin-film transistor (TFT) applications. Time-of-flight secondary ion mass spectrometry (ToF-SIMS) measurements identified that ultrathin SiO 2 as a multifunctional encapsulation layer effectively suppressed the oxygen adsorption on the back channel surface of p-SnO x and selectively diffused hydrogen across the entire thickness of the channel. Encapsulated p-SnO x -based TFTs demonstrated much enhanced channel conductance modulation in response to the gate bias applied, featuring higher on-state current and lower off-state current (on/off ratio > 10 3 ), field effect mobility of 3.41 cm 2 /(V s), and threshold voltages of ∼5-10 V. The fabricated devices show minimal deviations as small as ±6% in the TFT performance parameters, which demonstrates good reproducibility of the fabrication process. The relevance between the TFT performance and the effects of hydrogen permeation is discussed in regard to the intrinsic and extrinsic doping mechanisms. Density functional theory calculations reveal that hydrogen-related impurity complexes are in charge of the enhanced channel conductance with gate biases, which further supports the selective permeation of hydrogen through a thin SiO 2 encapsulation.