Publications by authors named "Yun Sung Choi"

This study reports the performance and durability of a protonic ceramic fuel cells (PCFCs) in an ammonia fuel injection environment. The low ammonia decomposition rate in PCFCs with lower operating temperatures is improved relative to that of solid oxide fuel cells by treatment with a catalyst. By treating the anode of the PCFCs with a palladium (Pd) catalyst at 500 °C under ammonia fuel injection, the performance (peak power density of 340 mW cm at 500 °C) is approximately two-fold higher than that of the bare sample not treated with Pd.

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Introduction: Displaced unstable distal third fractures of the humeral diaphysis are treated surgically through open reduction and internal fixation. Conventionally, surgeons prefer using long plates for secure fixation; however, we performed short plate dual plating for robust fixation that required a smaller incision and less dissection through an anterior approach. In this study, we report the results of dual plating of fractures of the humeral shaft, with radiographic evidence and clinical analysis.

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Unlabelled: An Arabidopsis β-glucosidase, AtBG1 is known to hydrolyze glucose-conjugated, biologically inactive abscisic acid (ABA) to produce active ABA, which increases the level of ABA in plants. Since an increase of ABA in plants confers tolerance against abiotic stress such as drought, we introduced the pCAMBIA3301 vector harboring the AtBG1 gene into creeping bentgrass through Agrobacterium-mediated transformation. After transformation, putative transgenic plants were selected using the BASTA resistance assay at a concentration of 0.

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Rationale: Aspirin-induced asthma (AIA) is a distinct clinical syndrome that affects up to 10% of adults with asthma. Although eicosanoid metabolites appear to play an important role in AIA, the exact pathogenic mechanism for the syndrome remains obscure. In addition, the proposed mechanism fails to explain why aspirin does not cause bronchoconstriction in all individuals.

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Particle inhalation-induced lung inflammation acts as an adjuvant to allergens or respiratory viral infection in a process that is mediated by macrophages and epitheliums. The production of interleukin (IL)-4 and IL-13 by activated T cells is involved in the augmentation of Th2-type immune responses to particles, and IL-25 induces the synthesis of IL-4 and IL-13. However, whether IL-13 and IL-25 are directly regulated by particle instillation in the lung has not been studied.

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Background: Th2 cytokines play pivotal roles in allergic inflammation, including eosinophilia, and their actions are antagonized by Th1 cytokines, conferring them therapeutic potential.

Methods: In this study, we examined the ability of a number of cytokines to suppress the activation of eosinophils that function as effector cells for allergic airway diseases.

Results: Interleukin (IL)-5, IL-6, and tumor necrosis factor (TNF) induced an eosinophil shape change, whereas interferon (IFN)-gamma significantly inhibited the shape change.

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