• Journal of Powder Materials
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• v.17 no.3
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• pp.230-234
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• 2010

Homogenous silica-coated $CoFe_2O_4$ samples with controlled silica thickness were synthesized by the reverse microemulsion method. First, 7 nm size cobalt ferrite nanoparticles were prepared by thermal decomposition methods. Hydrophobic cobalt ferrites were coated with controlled $SiO_2$ using polyoxyethylene(5)nonylphenylether (Igepal) as a surfactant, $NH_4OH$ and tetraethyl orthosilicate (TEOS). The well controlled thickness of the silica shell was found to depend on the reaction time and the amount of surfactant used during production. Thick shell was prepared by increasing reaction time and small amount of surfactant.

• Journal of The Korean Society of Agricultural Engineers
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• v.62 no.4
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• pp.23-31
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• 2020

Recently, meteorological disasters have been increasing by climate change, excessive rainfall, and landslide. The purpose is to develop new fabric concrete that can prevent and recover from damages because some of areas are vulnerable to meteorological disaster. Specifically, this technology can minimize time and space constraint when repairing the concrete structure and installing a formwork. The structure of fabric concrete is a mixture of fabric concrete and a high-speed hardened cement, Silica sand, wollastonite mineral fiber, fabric material and waterproof PVC fabric. In this study, the ratio of mechanical properties and durability of the fabric concrete mixture was evaluated by deriving the binder: silica sand mix ratio of the fabric concrete mixture and substituting part of the cement amount with wollastonite mineral fiber. Best binder in performance evaluation: Silica sand mix ratio is 6: 4 and the target mechanical performance and durability are the best when over 15% wollastonite binder is replaced by silicate mineral fiber.

• Molecular & Cellular Toxicology
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• v.5 no.4
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• pp.310-316
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• 2009

Some environmental chemicals have been shown to cause liver-toxicity as the result of bioaccumulation. Particularly, fungicides have been shown to cause varying degrees of hepatictoxicity and to disrupt steroid hormone homeostasis in in vivo models. The principal objective of this study was to evaluate the liver-toxic responses of environmental chemicals-in this case selected fungicides and parasiticides-in order to determine whether or not this agent differentially affected its toxicogenomic activities in hepatic tumor cell lines. To determine the gene expression profiles of 3 fungicides (triadimefon, myclobutanil, vinclozolin) and 1 parasiticide (dibutyl phthalate), we utilized a modified HazChem human array V2. Additionally, in order to observe the differential alterations in its time-dependent activities, we conducted two time (3 hr, 48 hr) exposures to the respective IC20 values of four chemicals. As a result, we analyzed the expression profiles of a total of 1638 genes, and we identified 70 positive significant genes and 144 negative significant genes using four fungicidic and parasiticidic chemicals, using SAM (Significant Analysis of Microarray) methods (q-value<0.5%). These genes were analyzed and identified as being related to apoptosis, stress responses, germ cell development, cofactor metabolism, and lipid metabolism in GO functions and pathways. Additionally, we found 120 genes among those time-dependently differentially expressed genes, using 1-way ANOVA (P-value<0.05). These genes were related to protein metabolism, stress responses, and positive regulation of apoptosis. These data support the conclusion that the four tested chemicals have common toxicogenomic effects and evidence respectively differential expression profiles according to exposure time.

• Pediatric Infection and Vaccine
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• v.30 no.2
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• pp.104-110
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• 2023

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) mainly causes respiratory symptoms such as fever, cough, sputum, and rhinorrhea, as well as digestive symptoms such as diarrhea, vomiting, and abdominal pain in children. In this report, we describe a case of a child with a SARS-CoV-2 infection who presented with epigastric pain and was subsequently diagnosed with acute pancreatitis without any concomitant infections in other organs. The epigastric pain was relieved with goal-directed vigorous fluid therapy for acute pancreatitis for 24 hours, and the serological and radiological findings normalized after two months. Acute pancreatitis should be considered as a differential diagnosis when a child with a history of COVID-19 visits the hospital with epigastric pain.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.3
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• pp.349-354
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• 2014

Elevation of intracellular calcium ($Ca^{{+}{+}}$) triggers degranulation of mast cells by bypassing receptor activation. Flos Sophora japonica L. has been used as a natural dying source and has been reported to have biological activities such as anti-inflammatory and anti-allergic effects through $Fc{\varepsilon}RI$ and IgE crosslinking. In the present investigation, we report the regulatory effect of ethanolic extract of Flos Sophora japonica L. (S.F) on allergic mediators produced by $Ca^{{+}{+}}$ ionophore activation in mast cells. S.F significantly inhibited calcium ionophore (A23187)-induced interleukin (IL)-4 and tumor necrosis factor (TNF)-${\alpha}$ production as well as mast cell degranulation. Furthermore, administration of S.F suppressed allergic reactions in a 2,4-dinitrofluorobenzene (DNFB)-induced allergic dermatitis mouse model. Both oral administration and ear painting using 50 mg/kg of S.F significantly reduced levels of cytokines such as IL-4, TNF, and interferon-${\gamma}$ in ear tissues compared to the DNFB alone-treated group. Serum IgE level in the S.F-treated group also decreased compared to the DNFB alone-treated group. Weights of spleens and lymph nodes in the S.F-treated groups also decreased compared to the control group. Considering the data, we conclude that S.F mediates its anti-allergic effects not only through $Fc{\varepsilon}RI$ stimulation but also $Ca^{{+}{+}}$ influx in mast cells.

• Journal of Conservation Science
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• v.36 no.5
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• pp.405-420
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• 2020

A convergence research was conducted on glass beads excavated at the ruins of Hapgang-ri, Sejong, using the archeology and conservation approach. The period of appearance of Jugu Towangmyo in the ruins of Hapgang-ri can be estimated to begin in the late 2^nd century; for Jugu Towangmyo No. 15, the period spans from the late 2^nd to early 3^rd century. Form, color, and manufacturing techniques of complete glass beads were examined, and the cross-sections and chemical composition of 16 samples were observed. Based on these analyses, the glass beads were divided into blue, purple, and red colors. The blue-colored beads could be further sub-divided based on their gloss and brightness; in contrast, the red-colored beads were highly uniform with regard to these parameters. Based on the stripe and bubble arrangement on the surface of the glass beads, their drawing technique was identified. Traces of heat treatment or polishing were observed at the ends of the beads. According to their chemical composition, the 16 samples were classified into 3 potash glass and 13 soda glass groups; in the latter, the properties of the stabilizers were divided according to the blue and red bead colors. The stabilizers of the red beads are unique in that they allow the distinction among beads excavated in other areas in South Korea owing to their compositional differences. Colorants in blue- and red-colored beads are cobalt (containing MnO), and copper and iron, respectively.

• BMB Reports
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• v.51 no.4
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• pp.163-164
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• 2018

CONSTANS (CO) induces the expression of FLOWERING LOCUS T (FT) in the photoperiodic pathway, and thereby regulates the seasonal timing of flowering. CO expression is induced and CO protein is stabilized by FLAVIN-BINDING KELCH REPEAT F-BOX PROTEIN 1 (FKF1) in the late afternoon, while CO is degraded by CONSTITUTIVE PHOTOMORPHOGENIC 1 (COP1) during the night. These regulatory cascades were thought to act independently. In our study, we investigated the relationship between FKF1 and COP1 in the regulation of CO stability in response to ambient light conditions. A genetic analysis revealed that FKF1 acts as a direct upstream negative regulator of COP1, in which cop1 mutation is epistatic to fkf1 mutation in the photoperiodic regulation of flowering. COP1 activity requires the formation of a hetero-tetramer with SUPPRESSOR OF PHYA-105 (SPA1), [$(COP1)_2(SPA1)_2$]. Light-activated FKF1 has an increased binding capacity for COP1, forming a FKF1-COP1 hetero-dimer, and inhibiting COP1 homo-dimerization at its coiled-coil (CC) domain. Mutations in the CC domain result in poor COP1 dimerization and misregulation of photoperiodic floral induction. We propose that FKF1 represses COP1 activity by inhibiting COP1 dimerization in the late afternoon under long-day conditions, resulting in early flowering.

• Applied Chemistry for Engineering
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• v.30 no.2
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• pp.241-246
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• 2019

In this paper, reactive surfactants were synthesized by using acrylic acid or 3-butenoic acid as nonionic surfactants, polyoxyethylene(23) lauryl ether (Brij 35) and polyoxyethylene(20) stearyl ether (Brij S20). The synthesis of surfactants was confirmed by FT-IR and $^1H$-NMR. The surface tension, emulsifying property, and foam power and stability were also measured. The surface tension value was 35~41 dyne/cm at an critical micelle concentration (cmc) which was measured as $1.0{\times}10^{-4}{\sim}9.7{\times}10^{-5}mol/L$ using a surface tension method. The emulsifying power of synthesized surfactant was measured with benzene, soybean oil and monomer. Also, the initial height of the bubbles and the height after 5 minutes were measured and the values were compared with each other.

• The Korea Journal of Herbology
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• v.35 no.1
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• pp.1-8
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• 2020

Objectives : This study was conducted to evaluate the effects of Corni Fructus, the dried fruits of Cornus officinalis Sieb., on unilateral common carotid artery occlusion (UCCAO) in mouse model. Methods : The Corni Fructus used in the experiment was extracted with anhydrous methanol, then filtered and freeze-dried. C57BL/6 mice used in the experiments were conducted left UCCAO surgery to set up UCCAO rodent model for mice. The mice were divided into five groups for evaluate the effect of methanol extract of Corni Fructus (COM) on UCCAO induced ischemic brain injury. The expression levels of nitric oxide in cerebrum and serum, body weight change were measured. To determine the effect of UCCAO and COM administration on brain neurons, morphological changes of the cerebrum through a microscope was conducted. And western blot was performed to confirm the underlying mechanism of neuroprotective effect of COM administration. Results : COM administered UCCAO groups (CO50, CO150, and CO500) had no significant effects on nitric oxide production in ipsilateral hemisphere proteins and sera. The CO500, 500 mg/kg COM administration, attenuated UCCAO-induced p38 inflammatory signaling pathway and inflammatory mediators such as iNOS and COX-2. The CO500 group showed resilient morphological changes of hippocampus neuronal cells about brain damage caused by decreased flow of blood. These group also showed decreased inflammation and cellular stress response in neuronal cells. Conclusions : From these results, COM has a neuroprotective property via moderating inflammatory factors and cellular stress inducing factors in brain cells.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.4
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• pp.397-407
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• 2022

This study investigated the collagen and texture properties of commonly consumed sliced raw fish species (CC-SRF) [olive flounder (OF), red seabream (RS), Atlantic salmon (AS), coho salmon (CoS) and sockeye salmon (SS)] distributed in Korea as sliced raw fishes. The crude lipid contents of CC-SRF were 5.5% for OF, 6.8% for RS, 18.5% for AS, 16.1% for CoS, and 5.7% for SS. The collagen content and solubility from CC-SRF were 622 mg/100 g and 78.0%, respectively, in OF, 270 mg/100 g and 75.6%, respectively, in RS, 237 mg/100 g and 24.1%, respectively, in AS, 341 mg/100 g and 65.7%, respectively, in CoS, and 246 mg/100 g and 17.9%, respectively, in SS. The texture of CC-SRF was affected by the lipid content, collagen content, acid solubility, hydroxylation, and cross linkage degree. The highest hardness of CC-SRF was obtained from OF, followed by RS, SS, AS and CoS. There was, however, no difference (P>0.05) in hardness between OF and RS and between AS and CoS.