Publications by authors named "Yunjung Oh"

Objective: An objective and convenient primary triage procedure is needed for prioritizing patients who need help in mass casualty incident (MCI) situations, where there is a lack of medical staff and available resources. This study aimed to develop an automated remote decision-making algorithm that remotely categorize a patient's emergency level using clinical parameters that can be measured with a wearable device.

Approach: The algorithm was developed according to the following procedures.

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Solar-energy conversion by photoelectrochemical (PEC) devices is driven by the separation and transfer of photogenerated charge carriers. Thus, understanding carrier dynamics in a PEC device is essential to realizing efficient solar-energy conversion. Here, we investigate time-resolved carrier dynamics in emerging low-cost SbSe nanostructure photocathodes for PEC water splitting.

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Organic-inorganic hybrid perovskite solar cells (PSCs) are considered promising materials for low-cost solar energy harvesting technology. An electron transport layer (ETL), which facilitates the extraction of photogenerated electrons and their transport to the electrodes, is a key component in planar PSCs. In this study, a new strategy to concurrently manipulate the electrical and optical properties of ETLs to improve the performance of PSCs is demonstrated.

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Amorphous molybdenum sulfide (a-MoS ) is a promising hydrogen evolution catalyst owing to its low cost and high activity. A simple electrodeposition method (cyclic voltammetry) allows uniform formation of a-MoS films on conductive surfaces. However, the morphology of a-MoS deposited on a TiO/SbSe photocathode could be modulated by varying the starting potential.

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Although a unique light-harvesting property was recently demonstrated in a photocathode based on 2-dimensional (2D) opals of CuFeO-shelled SiO microspheres, the performance of a monolayer of ultra-thin CuFeO-shelled microspheres is limited by ineffective charge separation. Herein, we propose an innovative design rule, in which an inner CuFeO/outer CuAlO double-shelled heterojunction is formed on each partially etched microsphere to obtain a hexagonally assembled 2D opal photoelectrode. Our Cu-delafossite double-shelled photocathode shows a dramatically improved charge separation capability, with a 9-fold increase in the photocurrent compared to that of the single-shelled counterpart.

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Efficient sunlight-driven water-splitting devices can be achieved by using an optically and energetically well-matched pair of photoelectrodes in a tandem configuration. The key for maximizing the photoelectrochemical efficiency is the use of a highly transparent front photoelectrode with a band gap below 2.0 eV.

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The purpose of this study is to investigate possible improvements in ICEVs by implementing fuzzy logic-based parallel hard-type power hybrid systems. Two types of conventional ICEVs (gasoline and diesel) and two types of HEVs (gasoline-electric, diesel electric) were generated using vehicle and powertrain simulation tools and a Matlab-Simulink application programming interface. For gasoline and gasoline-electric HEV vehicles, the prediction accuracy for four types of LDV models was validated by conducting comparative analysis with the chassis dynamometer and OBD test data.

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We demonstrated crystallization retardation of CHNHPbI thin film during single coating of precursor solution by simple addition of NaCl. NaCl was codissolved into a precursor mixture solution containing PbI and methylammonium iodide (MAI). Dissolved NaCl interacted with the PbI in solution and produced a stable intermediate phase, which was converted to a full-coverage uniform perovskite absorber layer via reaction with MAI during a single spin-coating.

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Although copper-based chalcopyrite materials such as CuInS2 have been considered promising photocathodes for solar water splitting, the fabrication route for a nanostructure with vertical orientation has not yet been developed. Here, a fabrication route for vertically aligned CuInS2 nanorod arrays from an aqueous solution using anodic aluminum oxide template-assisted growth and transfer is presented. The nanorods exhibit a phase-pure CuInS2 chalcopyrite structure and cathodic photocurrent response without co-catalyst loading.

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A nonvacuum solution-based approach can potentially be used to realize low cost, roll-to-roll fabrication of chalcopyrite CuIn(S,Se)2 (CISSe) thin film solar cells. However, most solution-based fabrication methods involve highly toxic solvents and inevitably require sulfurization and/or postselenization with hazardous H2S/H2Se gases. Herein, we introduce novel aqueous-based Cu-In-S and Se inks that contain an amine additive for producing a high-quality absorber layer.

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Background: Wound healing of the endothelium occurs through cell enlargement and migration. However, the peripheral corneal endothelium may act as a cell resource for the recovery of corneal endothelium in endothelial injury.

Aim: To investigate the recovery process of corneal endothelial cells (CECs) from corneal endothelial injury.

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Recently, environmental-friendly, solution-processed, flexible Cu(In,Ga)(S,Se)2 devices have gained significant interest, primarily because the solution deposition method enables large-scale and low-cost production of photovoltaics, and a flexible substrate can be implemented on uneven surfaces in various applications. Here, we suggest a novel green-chemistry aqueous ink that is readily achievable through the incorporation of molecular precursors in an aqueous medium. A copper formate precursor was introduced to lower the fabrication temperature, provide compatibility with a polyimide plastic substrate, and allow for high photovoltaic performance.

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Solution processing of earth-abundant Cu2ZnSn(S1-x,Sex)4 (CZTSSe) absorber materials is an attractive research area in the economical and large-scale deployment of photovoltaics. Here, a band-gap-graded CZTSSe thin-film solar cell with 7.1% efficiency was developed using non-toxic solvent-based ink without the involvement of complex particle synthesis, highly toxic solvents, or organic additives.

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We investigated the temporal alterations of adrenocorticotropic hormone (ACTH) immunoreactivity in the hippocampus after seizure onset. Expression of ACTH was observed within interneurons in the pre-seizure group of seizure sensitive gerbils, whereas its immunoreactivities were rarely detected in seizure resistant gerbil. Three hr after the seizure, ACTH immunoreactivity was significantly increased in interneurons within all hippocampal regions.

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To understand the effects of HCN as potential mediators in the pathogenesis of epilepsy that evoke long-term impaired excitability; the present study was designed to elucidate whether the alterations of HCN expression induced by status epilepticus (SE) is responsible for epileptogenesis. Although HCN1 immunoreactivity was observed in the hippocampus, its immunoreactivities were enhanced at 12 hrs following SE. Although, HCN1 immunoreactivities were reduced in all the hippocampi at 2 weeks, a re-increase in the expression at 2-3 months following SE was observed.

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Although the phospholipase C (PLC)β-1 isoform is associated with spontaneous seizure and distinctively expressed in the telencephalon, the distribution of PLCβ-1 expression in the epileptic gerbil hippocampus remains controversial. Therefore, we determined whether PLCβ-1 is associated with spontaneous seizure in an animal model of genetic epilepsy. In the present study, PLCβ-1 immunoreactivity was down-regulated in seizure-sensitive (SS) gerbils more than in seizure-resistant (SR) gerbils.

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Background: The gamma aminobutyric acid type A (GABA(A)) receptor is a prime target of many anesthetics, including midazolam and propofol. Although these anesthetics have sedative and hypnotic properties by enhancing GABA(A) receptor activity, their interactions at the GABA(A) receptors have not been explored. We investigated the interaction of midazolam and propofol with α(1)β(2)γ(2)L and α(1)β(2)γ(2)S GABA(A) receptors.

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A 47-year-old woman underwent orthotopic liver transplantation (OLT) for hepatitis B virus (HBV)-related end-stage liver cirrhosis. The patient received hepatitis B immunoglobulin prophylaxis after OLT. Despite the protective level of the serum anti-hepatitis-B surface antibody, HBV recurred at 22 months post-OLT and induced subacute hepatic failure.

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We report a case of hepatocellular carcinoma (HCC) with pulmonary metastases treated with repeated hepatic arterial infusion chemotherapy (HAIC) comprising epirubicin and cisplatin, and systemic infusion of 5-fluorouracil (a modified EC/F protocol), which led to complete remission. A 49-year-old man with compensated liver cirrhosis experienced intrahepatic recurrence of HCC with extensive lung metastases. The modified EC/F therapeutic protocol, which was applied at the tenth cycle every 4-5 weeks, resulted in disappearance of the pulmonary metastases and normalization of serum alpha-fetoprotein levels.

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A polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) technique was used to determine the microfloral composition during the fermentation of kimchi, a traditional Korean fermented vegetable food. The kimchi was fermented at 10 degrees C or 20 degrees C for 30 or 20 days, respectively. DGGE of the partially amplified 16S rDNA was performed and the most intense bands sequenced.

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