Publications by authors named "Sujeong Heo"

Fluorescent protein-DNA-binding peptides or proteins (FP-DBP) are a powerful means to stain and visualize large DNA molecules on a fluorescence microscope. Here, we constructed 21 kinds of FP-DBPs using various colors of fluorescent proteins and two DNA-binding motifs. From the database of fluorescent proteins (FPbase.

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The Korean government recommends intermittent operation of air purifiers (APs) as a measure to maintain indoor particulate matter (PM) concentrations below the mandatory standards and reduce exposure to indr PM (PM with a diameter smaller than ). However, there is no guideline to inform occupants of when and how long APs should be operated to comply with the standards. In this study, we developed a dynamic mass-balance model to predict indoor PM concentrations in an office considering penetration of outdoor particles, change in number of occupants, and operational status of the AP.

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As an eco-friendly alternative fuel material, ammonium dinitramide (ADN, NH₄N(NO₂)₂) is safe and stable at room temperature; however, it requires high purity for practical applications. A small amount of impurities can retard the catalytic decomposition of the monopropellant in the thruster, lower the specific impulse, and induce side effects such as clogging of the nozzle. Therefore, we purified NH₄N(NO₂)₂ by performing repeated extractions, adsorption by powdered activated carbon, and low-temperature extractions.

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To evaluate the level of fine particulate matters in elementary schools located in a high traffic area of Seoul and verify the emission source, a field study on the classrooms was conducted under the uncontrolled condition. The indoor PM was lower than that of the outdoors as indicated by an I/O ratio of 0.52-0.

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A hexaaluminate support was prepared by a co-precipitation method, and a metal (Cu, Pt, or Ir) was impregnated on the support to prepare a powdered catalyst. After that, organic and inorganic binders were added to the powdery catalyst and then pellets were formed. The so-formed catalysts were heat-treated at 1200°C, and their physicochemical properties were analyzed by N₂-adsorption, X-ray diffraction (XRD), X-ray fluorenscence (XRF), and scanning electron microscopy (SEM).

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The aim of this study is to elucidate the influence of an iridium loading strategy over hexaaluminate on the catalytic performance during the decomposition of liquid monopropellants based on ammonium dinitramide (ADN). Powder-type and pellet-type Ir/hexaaluminate catalysts were prepared and their chemico-physical properties were characterized by N₂ adsorption, XRD, XRF, and SEM. There were considerable differences in the Ir amounts present on the surface according to the impregnation method employed.

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Ordered mesoporous Cu-Mn binary metal oxide (meso-CuMnOx) catalysts were successfully synthesized by a hard-templating method from a mesoporous silica template with a cubic Ia3d mesostructure (KIT-6) or hydrophobic KIT-6, exhibiting a well-developed crystalline framework, a regular pore size distribution and a high surface area. The copper and manganese elements in the mesoporous Cu-Mn binary metal oxides (meso-CuMnOx-N and meso-CuMnOx-HP), obtained from the KIT-6 and hydrophobic KIT-6, respectively, were homogeneously dispersed in the whole particles. The activities of meso-CuMnOx catalysts for the decomposition of a liquid monopropellant containing an energetic ionic liquid, ammonium dinitramide, were much higher than that over a CuMnOx catalyst prepared by a conventional precipitation method.

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Mesoporous CuCe-based ternary metal oxides were synthesized using KIT-6 as a hard template through a nano-casting method. The mesoporous CuCe-based metal oxides were applied to the catalytic decomposition of the ammonium dinitramide-based liquid monopropellant. The decomposition onset temperature over the meso-CuCe ternary metal oxides was much lower than that over the CuCeOx catalyst prepared by conventional precipitation method.

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Conventional treatments do not appreciably improve fecundity in women with extremely low-serum levels of anti-Müllerian hormone (AMH). In Korea, herbal medicine is widely used to treat female infertility. We report a case in which an infertile woman with a very low AMH level naturally conceived after two months of herbal treatment (Bogungsamul-tang), ultimately giving birth to a full-term baby.

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Background: Inspired concentrations of desflurane ≥ 1 minimum alveolar anesthetic concentration (MAC) have been related to sympathetic stimulation such as hypertension and tachycardia. The current study examined whether labetalol, an α(1) and β-adrenergic antagonist would blunt these hemodynamic responses.

Methods: Fifty-four ASA physical status I patients, aged 20-60 years, were enrolled in this study.

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