• Clean Technology
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• v.27 no.4
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• pp.332-340
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• 2021

With the recent reinforcement of emission standards, it is necessary to make efforts to reduce NOx from air pollutant-emitting workplaces. The NOx reduction method mainly used in industrial facilities is selective catalytic reduction (SCR), and the most commercial SCR catalyst is the ceramic honeycomb catalyst. This study was carried out to reduce the NOx emitted from steel plants by applying De-NOx catalyst coated on metallic monolith. The De-NOx catalyst was synthesized through the optimized coating technique, and the coated catalyst was uniformly and strongly adhered onto the surface of the metallic monolith according to the air jet erosion and bending test. Due to the good thermal conductivity of metallic monolith, the De-NOx catalyst coated on metallic monolith showed good De-NOx efficiency at low temperatures (200 ~ 250 ℃). In addition, the optimal amount of catalyst coating on the metallic monolith surface was confirmed for the design of an economical catalyst. Based on these results, the De-NOx catalyst of commercial grade size was tested in a semi-pilot De-NOx performance facility under a simulated gas similar to the exhaust gas emitted from a steel plant. Even at a low temperature (200 ℃), it showed excellent performance satisfying the emission standard (less than 60 ppm). Therefore, the De-NOx catalyst coated metallic monolith has good physical and chemical properties and showed a good De-NOx efficiency even with the minimum amount of catalyst. Additionally, it was possible to compact and downsize the SCR reactor through the application of a high-density cell. Therefore, we suggest that the proposed De-NOx catalyst coated metallic monolith may be a good alternative De-NOx catalyst for industrial uses such as steel plants, thermal power plants, incineration plants ships, and construction machinery.

• Applied Chemistry for Engineering
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• v.30 no.1
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• pp.114-121
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• 2019

In this study, antioxidative, antibacterial and cytoprotective effects of the ethanol extract and ethylacetate fraction of Lycopus lucidus (L. lucidus) were compared and analyzed. Free radical scavenging activities ($FSC_{50}$) of the L. lucidus extract and fraction were found to be 65.1 and $64.9{\mu}g/mL$ respectively. In the $Fe^{3+}-EDTA/H_2O_2$ system, the reactive oxygen species (ROS) scavenging activities ($OSC_{50}$) for the extract and fraction were 6.6 and $6.3{\mu}g/mL$, respectively which showed excellent total antioxidant abilities. The extract showed antibacterial activity against S. aureus, while the fraction showed in all the bacteria except for A. niger. The cytoprotective effect of L. lucidus extract was compared to that of the fraction and the effect against $^1O_2$-induced cellular damage of human erythrocytes (${\tau}_{50}$) was 51.3 and 73.7 min at $50{\mu}g/mL$, respectively. For the cytoprotective effect of keratinocytes damaged by $H_2O_2$ and UVB, the extracts did not show any efficacy but showed efficacy at $1-2{\mu}g/mL$, respectively. The fraction increased the cell viability up to 85.8 and 81.9%, respectively. As a result of intracellular ROS scavenging activity, the scavenging activity was observed at $1-2{\mu}g/mL$ of the fraction. From the results comparing the physiological activities of L. lucidus extract and the fraction, the ethylacetate fraction of L. lucidus has antioxidative effect similar to that of the extract whereas superior antimicrobial and cytoprotective effects than that of the extract. Overall, the ethylacetate fraction of L. lucidus protects cells from an external stress which can be used as a potential cosmetic material.

• The Korean Journal of Nuclear Medicine Technology
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• v.22 no.2
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• pp.74-78
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• 2018

Purpose $[^{11}C]$acetate has been proved useful in detecting the myocardial oxygen metabolism and various malignancies including prostate cancer, hepatocellular carcinoma, renal cell carcinoma and brain tumors. The purpose of study was to improve the radiosynthesis yield of $[^{11}C]$acetate on a automated radiosynthesis module. Materials and Methods $[^{11}C]$acetate was prepared by carboxylation of grignard reagent, methylmagnesium chloride, with $[^{11}C]$$CO_2$ gas, followed by hydrolysis with 1 mM acetic acid and purification using solid phase extraction cartridges. The effect of the reaction temperature ($0^{\circ}C$, $10^{\circ}C$, $-55^{\circ}C$) and cyclotron beam time (10 min, 15 min, 20 min, 25 min) on the radiosynthesis yield were investigated in the $[^{11}C]$acetate labeling reaction. Results The maximum radiosynthesis yield was obtained at $-10^{\circ}C$ of reaction temperature. The radioactivities of $[^{11}C]$acetate acquired at $-10^{\circ}C$ reaction temperature was 2.4 times higher than those of $[^{11}C]$acetate acquired at $-55^{\circ}C$. Radiosynthesis yield of $[^{11}C]$acetate increased with increasing cyclotron beam time. Conclusion This study shows that radiosynthesis yield of $[^{11}C]$acetate highly dependent on reaction temperature. The best radiosynthesis yield was obtained in reaction of grignard reagent with $[^{11}C]$$CO_2$ at $-10^{\circ}C$. This radiolabeling conditions will be ideal for routine clinical application.

• Korean Journal of Clinical Laboratory Science
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• v.51 no.2
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• pp.245-251
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• 2019

This study examined the effects of 2-methoxy-1,4-naphthoquinone (MQ) on the monocyte chemoattractant protein-1 (MCP-1)-induced migration of monocytes, which is an important phenomenon for the body defense and immune response. MQ is a major component extracted from Impatiens balsamina leaves, which have been used for many years in Asian medicine for the treatment of a range of diseases and pain. The cytotoxicity of MQ began to appear at a concentration of $10{\mu}M$, and approximately 50% cytotoxicity was confirmed at $100{\mu}M$. The MCP-1 induced migration of the THP-1 monocyte cell line increased after MQ treatment in a dose dependent manner and the largest increase was observed at $0.1{\mu}M$. The level of cAMP expression decreased after a treatment with $0.1{\mu}M$ MQ. The phosphorylation of extracellular signal-regulated kinases 1/2 (Erk1/2), a key signaling protein involved in the signaling pathway of C-C motif chemokine receptor 2 (CCR2), a receptor for MCP-1, was increased by the simultaneous treatment of $0.1{\mu}M$ MQ. These results show that MQ increases the MCP-1-induced migration of THP-1, decreases the level of cAMP expression, and increases the level of Erk1/2 phosphorylation.

• Journal of Life Science
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• v.31 no.2
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• pp.229-236
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• 2021

This study was carried out to evaluate the antioxidant properties of the dried leaves and branches of Stewartia koreana Nakai. The dried leaf and branch of S. koreana were extracted with 70% ethanol at 80℃. The antioxidant activities of ethanol extracts of S. koreana leaf (EESL) and S. koreana branch (EESB) were analyzed. The total polyphenol contents in EESL and EESB were 162.57±0.9 mg of GAEs/extract g and 59.1±0.9 mg of GAEs/extract g, respectively. The flavonoid contents in EESL and EESB were 59.1±0.9 mg of QEs/extract g and 4.7±0.1 mg of QEs/extract g, respectively. EESL showed a better scavenging ability with DPPH and ABTS than EESB, at 0.4 mg/ml. Moreover, EESL were more effective according to ORAC values than EESL. The toxicity of EESL was investigated using a WST-1 assay on the human skin fibroblast cell line CCD-986sk. Therefore, EESL can be used as a potential source of functional, naturally-sourced material in cosmetics as well as food.

• Journal of Life Science
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• v.31 no.3
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• pp.330-337
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• 2021

This study was conducted to investigate the potential of Stewartia koreana as oral healthcare materials. The antibacterial activity of ethanol extracts from leaves and branches of S. koreana against oral bacteria was confirmed. The leaf and branch extracts (1 mg/disc) showed antibacterial activity against P. gingivalis only among several tested oral bacteria. The leaf extracts showed higher antibacterial activity, with values similar to those of chlorhexidine, which was used as a positive control. The MIC of the leaf extract against P. gingivalis was 0.4 mg/ml and showed bacteriostatic action. The inhibitory effects of the extract on biofilm formation and on gene expression related to biofilm formation by P. gingivalis were determined by biofilm biomass staining, scanning electron microscopy (SEM), and qRT-PCR analysis. The biofilm production rate and cell growth of P. gingivalis in the cultures treated with 0.2-2.0 mg/ml of S. koreana leaf extracts were significantly decreased in a concentration-dependent manner. The inhibitory effect on the formation of P. gingivalis biofilms at concentrations of 1 mg/ml was confirmed by SEM. The qRT-PCR analysis showed concentration-dependent suppression of the fimA and fimB gene expression associated with fimbriae formation in the cultures treated with 0.2-2.0 mg/ml S. koreana leaf extract. These results support the conclusion that S. koreana leaf extracts can be used as oral healthcare materials derived from natural materials, as demonstrated by the antibacterial action and inhibition of biofilm formation of P. gingivalis.

• Journal of The Korean Society of Grassland and Forage Science
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• v.40 no.4
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• pp.203-208
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• 2020

This experiment was conducted to investigate the effects of feeding TMR(Total Mixed Ration) with Sasa quelpaertensis Nakai of Jeju cross-bred horses on the body weight and blood composition. Fourteen herds of Jeju cross-bred horses older than 36 months were selected as experimental animals. The experiment was conducted by dividing the herds into seven herds for feeding TMR with 20% Sasa quelpaertensis Nakai(treatment) and another seven herds for feeding TMR without Sasa quelpaertensis Nakai(control) and water were fed ad libitum. In the 12th week, the MPV(mean platelet volume) was statistically significantly higher with Sasa TMR than with control (p<0.05). However, both MPV levels are within a normal range and there were no health problems. With regard to the levels of cholesterol, there was a statistically significant difference between the 33.8±5.9 mg/㎗ with individual management and 25.4±8.2 mg/㎗ with control group (p<0.05). But It are also within a normal range and there were no health problems. In conclusion, feeding TMR with 20% Sasa quelpaertensis Nakai of Jeju cross-bred horses could be utilized as a feeding method for horse.

• Journal of the Korean Electrochemical Society
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• v.24 no.4
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• pp.120-132
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• 2021

Although the development of high-Nickel is being actively carried out to solve the capacity limitation and the high price of raw cobalt due to the limitation of high voltage use of the existing LiCoO₂, the deterioration of the battery characteristics due to the decrease in structural stability and increase of the Ni content. It is an important cause of delaying commercialization. Therefore, in order to increase the high stability of the Ni-rich ternary cathod material LiNi_0.6Co_0.2Mn_0.2O₂, precursor Ni_0.6Co_0.2Mn_0.2-x(OH)₂/xTiO₂ was prepared using a nanosized TiO₂ suspension type source for uniform Ti substitution in the precursor. It was mixed with Li₂CO₃, and after heating, the cathode active material LiNi_0.6Co_0.2Mn_0.2-xTi_xO₂ was synthesized, and the physical properties according to the Ti content were compared. Through FE-SEM and EDS mapping analysis, it was confirmed that a positive electrode active material having a uniform particle size was prepared through Ti-substituted spherical precursor and Particle Size Analyzer and internal density and strength were increased, XRD structure analysis and ICP-MS quantitative analysis confirmed that the capacity was effectively maintained even when the Ti-substituted positive electrode active material was manufactured and charging and discharging were continued at high temperature and high voltage.

• Journal of the Korean Orthopaedic Association
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• v.56 no.4
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• pp.310-316
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• 2021

Purpose: Septic arthritis of the knee is an orthopedic emergency that requires early diagnosis and surgical treatment. This study examined the effectiveness of drain insertion and irrigation in the treatment of septic arthritis of the knee under local anesthesia. Materials and Methods: A retrospective study was conducted on nine cases (eight patients) diagnosed with septic arthritis of the knee from September 2017 to February 2020 and treated with drain insertion and irrigation under local anesthesia. After penetrating through the superolateral portal to the superomedial portal and inserting the drain, daily irrigation of approximately 3 L of normal saline was done. The following were investigated: age, sex, underlying disease, cause, degree of osteoarthritis, time from diagnosis to surgery, duration of hospitalization, duration of normalization of C-reactive protein, and smear and culture. Results: The initial white blood cell count of joint fluid was 71,472±51,667/mm³ (32,400-203,904/mm³), and polymorphic leukocytes were 91.1%±2.6% (86%-95%). The average time from diagnosis to surgery was 8.3±1.3 hours (6-10 hours), and the irrigation period was 8.2±3.2 days (4-15 days). The average length of hospitalization was 20.8±8.7 days (9-37 days). There was no reoperation or recurrence. Smear and culture tests were not identified. Conclusion: In the treatment of septic arthritis of the knee, the insertion of a drain tube and irrigation under local anesthesia is a relatively fast and simple method to reduce pain by repetitive draining of purulent joint fluid and can be used as an alternative treatment for patients with a risk of general or spinal anesthesia.

• Food Science and Preservation
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• v.31 no.1
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• pp.183-196
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• 2024

This study investigated the protective effect of the aqueous extract of Eucommia ulmoides leaves (AEEL) against high glucose-induced human colon epithelial HT-29 cells. The 2,2'-azino-bis (3-ethyl benzothiazoline-6-sulfonic acid) (ABTS), 1,1-diphenyl-2-picrylhydrazy (DPPH) radical scavenging activities, ferric reducing/antioxidant power (FRAP), and malondialdehyde (MDA) analyses indicated that AEEL had significant antioxidant activities. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay showed that AEEL increased cell viability against high glucose-, H₂O₂-, and lipopolysaccharide (LPS)-induced cytotoxicity in HT-29 cells. Also, the 2'-7'-dichlorodihydrofluorescein diacetate (DCF-DA) assay indicated that AEEL decreased intracellular reactive oxygen species (ROS) against high glucose-, H₂O₂-, and lipopolysaccharide (LPS)-induced cytotoxicity in HT-29 cells. AEEL showed inhibitory activities against α-glucosidase and inhibited the formation of advanced glycation end products (AGEs). AEEL showed significant positive effects on the viability and titratable acidity of L. brevis. The high-performance liquid chromatogram (HPLC) analysis identified chlorogenic acid and rutin as the major compounds of AEEL. These results suggested that AEEL has the potential to be used as a functional food source to suppress blood glucose levels and protect the gut from high glucose-induced oxidative stress.