Publications by authors named "Jin Ha Hwang"

Combinations of semiconductor metal oxide (SMO) sensors, electrochemical (EC) sensors, and photoionization detection (PID) sensors were used to discriminate chemical hazards on the basis of machine learning. Sensing data inputs were exploited in the form of either numerical or image data formats, and the classification of chemical hazards with high accuracy was achieved in both cases. Even a small amount of gas sensing or purging data (input for ∼30 s) input can be exploited in machine-learning-based gas discrimination.

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A high-performance semiconductor metal oxide gas sensing strategy is proposed for efficient sensor-based disease prediction by integrating a machine learning methodology with complementary sensor arrays composed of SnO- and WO-based sensors. The six sensors, including SnO- and WO-based sensors and neural network algorithms, were used to measure gas mixtures. The six constituent sensors were subjected to acetone and hydrogen environments to monitor the effect of diet and/or irritable bowel syndrome (IBS) under the interference of ethanol.

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Unlabelled: This study was conducted to investigate the antimicrobial effects of 300 Asian plant extracts (PEs) against pathogenic and spoilage bacteria. The antimicrobial activities were examined using agar well or agar disc diffusion, and micro-titer methods. Results revealed that PEs exhibited higher antimicrobial effects against Gram-positive bacteria compared than against Gram-negative bacteria.

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Metal thin films have been widely used as conductors in semiconductor devices for several decades. However, the resistivity of metal thin films such as Cu and TiN increases substantially (>1000%) as they become thinner (<10 nm) when using high-density integration to improve device performance. In this study, the resistivities of MAX-phase VAlC films grown on sapphire substrates exhibited a significantly weaker dependence on the film thickness than conventional metal films that resulted in a resistivity increase of only 30%, as the VAlC film thickness decreased from approximately 45 to 5 nm.

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In this work, loess-based materials were designed based on a multicomponent composite materials system for ecofriendly natural three-dimensional (3D) printing involving quick lime, gypsum, and water. The 3D printing process was monitored as a function of gypsum content; in terms of mechanical strength and electrical resistance, in the cube-shaped bulk form. After initial optimization, the 3D printing composition was refined to provide improved printability in a 3D printing system.

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Responsive materials designed to generate signals for both surface-enhanced Raman spectroscopy (SERS) and phosphorescence lifetime-"dual-mode"-measurements are described. To demonstrate this concept, we incorporated pH-sensitive and oxygen-sensitive microdomains into a single hydrogel that could be interrogated via SERS and phosphorescence lifetime, respectively. Microdomains consisted two populations of discrete microcapsules containing either (1) gold nanoparticles capped with pH-sensitive Raman molecules or (2) oxygen-sensitive benzoporphyrin phosphors.

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This study investigated the pull-out resistance of superelastic shape memory alloy (SMA) short fibers in mortar with consideration of various end-anchorages that provide different anchoring actions. For the purpose, four types of SMA fibers were prepared using NiTi SMA wires with a diameter of 1.0 mm and the following four end shapes: straight (ST), L-shaped (LS), N-shaped (NS), and spearhead-shaped (SH).

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To date, most of the studies on quantum dot-light-emitting diodes (QLEDs) have been dedicated to the fabrication of high-efficiency monochromatic devices. However, for the ultimate application of QLEDs to the next-generation display devices, QLEDs should possess a full-color emissivity. In this study, we report the fabrication of all-solution-processed full-color-capable white QLEDs with a standard device architecture, where sequentially stacked blue (B)/green (G)/red (R) quantum dot (QD)-emitting layers (EMLs) are sandwiched by poly(9-vinylcarbazole) as the hole transport layer and ZnO nanoparticles (NPs) as the electron transport layer.

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Self-healing is an essential property of smart concrete structures. In contrast to other structural metals, shape memory alloys (SMAs) offer two unique effects: shape memory effects, and superelastic effects. Composites composed of SMA wires and conventional cements can overcome the mechanical weaknesses associated with tensile fractures in conventional concretes.

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Electrodes composed of multilayered graphene grown on a metal foam (GMF) were prepared by directly growing multilayer graphene sheets on a three-dimensional (3D) Ni-foam substrate via a self-catalyzing chemical vapor deposition process. The multilayer graphene sheets are successfully grown on the Ni-foam substrate surface, maintaining the unique 3D macroporous structure of the Ni foam. The potential use of GMF electrodes in nonaqueous redox flow batteries (RFBs) is carefully examined using [Co(bpy)] and [Fe(bpy)] redox couples.

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The effectiveness of sanitizing treatments was investigated on reducing pathogens inoculated in whole or cut fresh vegetables, including Brussels sprouts, carrots, cherry tomatoes, paprika, and lettuce. These products were inoculated with O157:H7, serovar Typhimurium, and and then treated with chlorine and alcohol sanitizers, followed by the subsequent washing procedure in sterile distilled water at 25°C for 5min. Alcohol sanitizer was the most effective in inhibiting O157:H7, S.

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Ischemic stroke and cardiovascular disease can occur from blockage of blood vessels by fibrin clots formed naturally in the body. Therapeutic drugs of anticoagulant or thrombolytic agents have been studied; however, various problems have been reported such as side effects and low efficacy. Thus, development of new candidates that are more effective and safe is necessary.

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A heteronemertean, , was collected in Han River Estuary, South Korea. This estuarine nemertean has been known by the local fishermen for harmful effects to the glass eels, juveniles of Japanese eel , migrating to fresh water. The present study confirmed the neurotoxic effects of this heteronemertean ribbon worm at the cellular level.

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In Southeast Asian countries, including Korea, China, and Japan, the considerable amounts of raw fish have been annually consumed in the manner of live fish fillets without minimally thermal processing, increasing the risks of causing food-borne diseases. This study investigated the occurrence of total aerobic bacteria (TAB), coliform, , serovar spp., , and in jacopevers and plaices.

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This study investigated biofilm formation, cell surface hydrophobicity, colony spreading, and slime production for 112 strains isolated from various sources (leaf vegetables, pea leaf, perilla leaf, , person, and animal). When biofilm formation was classified by origin, isolated from animal origin showed a significantly higher level of biofilm formation than others (≤0.05).

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The layer-by-layer modification of ≈5 nm mercaptocarboxylic acid stabilized gold nanoparticles was studied in an effort to illustrate effective means to overcome practical issues in handling and performing surface modification of such extremely small materials. To accomplish this, each layer deposition cycle was separated into a multi-step process wherein solution pH was controlled in two distinct phases of polyelectrolyte adsorption and centrifugation. Additionally, a solvent precipitation step was introduced to make processing more amenable by concentrating the sample and exchanging solution pH before ultracentrifugation.

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Atopic dermatitis (AD) is a complex skin disease primarily characterized by psoriasis of the stratum corneum. AD drugs have usually been used in acidic and hydrophilic solvents to supply moisture and prevent lipid defects. Ceramide is a typical treatment agent to regenerate the stratum corneum and relieve symptoms of AD.

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Article Synopsis
  • The study analyzed 120 primary breast cancer samples and adjacent normal tissues using whole-transcriptome sequencing to discover new gene fusion transcripts linked to breast cancer.* -
  • Out of thousands of potential fusions detected, the researchers focused on those found in HER2 subtype cancers and validated 32 out of 70 candidates, including six recurrent fusions.* -
  • Notably, a novel fusion called EEF1DP3-FRY was identified in about 6.7% of the samples and is believed to cause early termination of the FRY gene, which is important for cell structure during division.*
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Micro-contact printing of self-assembly monolayers (SAMs), i.e., octadecyl-trichlorosilane (OTS) was combined with self limiting atomic layer deposition in order to fabricate the selective deposition of nickel oxide on amorphous Si thin films.

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Two-dimensional electron gas (2DEG) at the complex oxide interfaces have brought about considerable interest for the application of the next-generation multifunctional oxide electronics due to the exotic properties that do not exist in the bulk. In this study, we report the integration of 2DEG into the nonvolatile resistance switching cell as a bottom electrode, where the metal-insulator transition of 2DEG by an external field serves to significantly reduce the OFF-state leakage current while enhancing the on/off ratio. Using the Pt/Ta2O5-y/Ta2O5-x/SrTiO3 heterostructure as a model system, we demonstrate the nonvolatile resistance switching memory cell with a large on/off ratio (>10(6)) and a low leakage current at the OFF state (∼10(-13) A).

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Recognizing that steel fibers can supplement the brittle tensile characteristics of concrete, many studies have been conducted on the shear performance of steel fiber reinforced concrete (SFRC) members. However, previous studies were mostly focused on the shear strength and proposed empirical shear strength equations based on their experimental results. Thus, this study attempts to estimate the strains and stresses in steel fibers by considering the detailed characteristics of steel fibers in SFRC members, from which more accurate estimation on the shear behavior and strength of SFRC members is possible, and the failure mode of steel fibers can be also identified.

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Digital quantification of a two-dimensional structure was applied to a GDC(Gd₂O₃-doped CeO₂)/LSM(La₀.₈₅Sr₀.₁₅MnO₃) composite cathode employed for solid oxide fuel cells.

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P-type copper oxide nanowires (NWs) were grown on metallic copper plates and sapphire substrates. Significant variations in the morphology and distribution of the NWs, due to underlying differences in the growth mechanism and the NW densities, were observed based on the nature of the substrate utilized. The use of copper plates induced an extremely high density of copper oxide nanowires on temperature-dependent copper oxide layers.

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Annotation of the recently sequenced genome of the pea aphid (Acyrthosiphon pisum) identified a gene ApAQP2 (ACYPI009194, Gene ID: 100168499) with homology to the Major Intrinsic Protein/aquaporin superfamily of membrane channel proteins. Phylogenetic analysis suggests that ApAQP2 is a member of an insect-specific clade of this superfamily. Homology model structures of ApAQP2 showed a novel array of amino acids comprising the substrate selectivity-determining "aromatic/arginine" region of the putative transport pore.

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The nanolaminate Al2O3/Cu/Al2O3 structures were constructed on p-type Si (001) substrates using atomic layer deposition (ALD) process with the aim to fabricating nonvolatile charge-trap memories. Low temperature Cu thin layers were deposited through plasma-enhanced atomic layre depositon of Cu aminoalkoxide (Cu(dmamb)2) combined with hydrogen plasma and Al2O3 layers were prepared by thermal atomic layer deposition of trimethylaluminum (TMA) combined with H2O. Nonvolatile features were confirmed using capacitance-voltage (C-V) measurements.

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