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Chiseon Ryu,1 Hwangjae Lee,1 Hohyeon Kim,2 Seong Hwang,1 Yaser Hadadian,2,3 Ayeskanta Mohanty,4 In-Kyu Park,4 Beongki Cho,1 Jungwon Yoon,2,3 Jae Young Lee1 1School of Materials Science and Engineering, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea; 2School of Integrated Technology, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea; 3Research Center for Nanorobotics in Brain, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea; 4Department of Biomedical Sciences, Chonnam National University Medical School, Hwasun-gun, Jeollanam-do, Republic of KoreaCorrespondence: Jungwon Yoon; Jae Young Lee Tel +82 62 715 5332; +82 62 715 2358Email jyoon@gist.ac.kr; jaeyounglee@gist.ac.krIntroduction: Iron oxide magnetic nanoparticles (IONPs) have attracted considerable attention for various biomedical applications owing to their ease of synthesis, strong magnetic properties, and biocompatibility. In particular, IONPs can generate heat under an alternating magnetic field, the effects of which have been extensively studied for magnetic hyperthermia therapy. However, the development of IONPs with high heating efficiency, biocompatibility, and colloidal stability in physiological environments is still required for their safe and effective application in biomedical fields.Methods: We synthesized magnetic IONP/polymer nanocomposites (MNCs) by embedding IONPs in a poly(L-lactic acid) (PLA) matrix via nanoemulsion. The IONP contents (Fe: 9– 22 [w/w]%) in MNCs were varied to investigate their effects on the magnetic and hyperthermia performances based on their optimal interparticle interactions. Further, we explored the stability, cytocompatibility, biodistribution, and in vivo tissue compatibility of the MNCs.Results: The MNCs showed enhanced heating efficiency with over two-fold increase compared to nonembedded bare IONPs. The relationship between the IONP content and heating performance in MNCs was nonmonotonous. The highest heating performance was obtained from MNC2, which contain 13% Fe (w/w), implying that interparticle interactions in MNCs can be optimized to achieve high heating performance. In addition, the MNCs exhibited good colloidal stability under physiological conditions and maintained their heating efficiency during 48 h of incubation in cell culture medium. Both in vitro and in vivo studies revealed excellent biocompatibility of the MNC.Conclusion: Our nanocomposites, comprising biocompatible IONPs and PLA, display improved heating efficiency, good colloidal stability, and cytocompatibility, and thus will be beneficial for diverse biomedical applications, including magnetic hyperthermia for cancer treatment.Keywords: iron oxide nanoparticle, hyperthermia, inter-particle interactions, nanomedicine

Electrochemical CO2 conversion to fuel molecules is an attractive strategy towards atmospheric carbon attenuation. In the fuel conversion catalysis of carbon dioxide, surface adsorbed CO was often identified as a key intermediate, and the inherently low concentration of which has recently been highlighted as an important factor in the low yields of C2+ fuels. Here a bipotentiostatic tandem catalysis system was designed such that the loads for electrosynthesis of CO from CO2 and the subsequent C–C coupling reaction were split to two separate working electrodes with independent potential programming. Coulometric tracking of the reaction indicated efficient turnover of the electrosynthetic CO to fuel molecules at the second working electrode, achieving a high C2+ yield of 67.3% and a 6.5% faradaic efficiency towards 1-propanol. Importantly, the unique capability of the tandem catalysis system allowed control of the CO flux to the second working electrode, which enabled the direct quantification of the C–C coupling turnover frequency on a surface copper atom (0.43 ± 0.06 s−1), when the reaction current was electrode-kinetics controlled with sufficient CO mass transport. Furthermore, the bipotentiostatic reaction platform developed here exhibits modular tunability, such that the expansion of the platform to other sequential electrocatalyses is imaginable. [ABSTRACT FROM AUTHOR]

Lithium–air batteries are highlighted as one of promising next generation battery technology with high gravimetric energy density. To date, however, cyclability of lithium–air batteries has been low, insufficient for commercial use. Many recent research accounts focused on understanding the mechanism of the discharge reaction in attempts to improve the cyclability, and revealed that two structurally distinct lithium peroxide species form during discharge, thin films and toroids, among which toroids formation results in beneficial effects in both cyclability and overall discharge capacity. In this work, scanning electrochemical microscopy was applied to investigate electron transfer dynamics of the two lithium peroxide species, from which a much faster surface electron transfer was observed from lithium peroxide toroids compared to that of thin films. The difference is postulated to stem from the difference in the formation mechanism of the two species. [ABSTRACT FROM AUTHOR]

This article, published in the journal Endoscopy, presents a retrospective study on the long-term outcomes of endoscopic submucosal dissection (ESD) for undifferentiated early gastric cancer (EGC). The study analyzed two groups of patients based on tumor size (group A: up to 2 cm, group B: 2-3 cm) and evaluated en bloc resection, R0 resection, and curative resection. The results showed that while the R0 resection rate was lower in group B compared to group A, the recurrence rate was not significantly different between the two groups. The study suggests that ESD is a recommended treatment for undifferentiated EGC with a size of 2 to 3 cm. [Extracted from the article]

This article compares the effectiveness of endoscopic subtumoral dissection (ESD) and surgical resection for the removal of gastric subepithelial tumors (GSETs) originating from the muscularis propria. The study involved 17 patients who underwent ESD and 76 patients who underwent surgical resection. The ESD group had smaller tumor sizes and higher endoluminal ratios compared to the surgery group. While the ESD group had a lower rate of complete resection and higher complication rates, the severity of complications was higher in the surgery group. The study suggests that ESD can be a viable alternative to surgical resection for certain types of GSETs. [Extracted from the article]

ABSTRACT Computational fluid dynamic (CFD) analysis of the thermal flow in the combustion chamber of a solid waste incinerator provides crucial insight into the incinerator's performance. However, the interrelation of [...]