• Title/Summary/Keyword: Korean Studies

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Determination of Stream Reach for River Environment Assessment System Using Satellite Image (위성영상을 활용한 하천환경 평가 세구간 설정)

  • Kang, Woochul;Choe, Hun;Jang, Eun-kyung;Ko, Dongwoo;Kang, Joongu;Yeo, Hongkoo
    • Ecology and Resilient Infrastructure
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    • v.8 no.4
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    • pp.179-193
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    • 2021
  • This study examines the use of satellite images for river classification and determination of stream reach, which is the first priority in the river environment assessment system. In the river environment assessment system used in South Korea, it is proposed to set a stream reach by using 10 or 25 times the width of the river based on the result of river classification. First, river classification for the main stream section of Cheongmi stream was performed using various river-related data. The maximum likelihood method was applied for land cover classification. In this study, Sentinel-2 satellite imagery, which is an open data technology with a resolution of 10 m, was used. A total of four satellite images from 2018 was used to consider various flow conditions: February 2 (daily discharge = 2.39 m3/s), May 23 (daily discharge = 15.51 m3/s), June 2 (daily discharge = 3.88 m3/s), and July 7 (daily discharge = 33.61 m3/s). The river widths were estimated from the result of land cover classification to determine stream reach. The results of the assessment reach classification were evaluated using indicators of stream physical environments, including pool diversity, channel sinuosity, and river crossing shape and structure. It is concluded that appropriate flow conditions need to be considered when using satellite images to set up assessment segments for the river environment assessment system.

Inhibitory Effect of Protaetiamycine 9 Derived from Protaetia brevitarsis seulensis Larvae on LPS-mediated Inflammation in RAW264.7 Cells (LPS로 자극한 RAW264.7 대식세포에서 흰점박이꽃무지 유충 유래 Protaetiamycine 9의 항염증 효과)

  • Choi, Ra-Yeong;Seo, Minchul;Lee, Joon Ha;Kim, In-Woo;Kim, Mi-Ae;Hwang, Jae-Sam
    • Journal of Life Science
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    • v.31 no.11
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    • pp.987-994
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    • 2021
  • Our previous studies have reported that antimicrobial peptides (AMPs) derived from the larvae of white-spotted flower chafer (Protaetia brevitarsis seulensis) exert anti-inflammatory and neuroprotective activities. This study explored the anti-inflammatory effects of protaetiamycine 9 (CVLKKAYFLTNLKLRG-NH2), a novel AMP, derived from P. b. seulensis against lipopolysaccharide (LPS)-mediated inflammatory response in RAW264.7 macrophage cells. Protaetiamycine 9 (25, 50, 75, and 100 ㎍/ml) did not cause cytotoxic effects against RAW264.7 cells. The RAW264.7 cells were pre-treated with various concentrations of protaetiamycine 9 (25-100 ㎍/ml) for 1 hr and then exposed to LPS (100 ng/ml) for 24 hr. Protaetiamycine 9 treatments decreased the LPS-induced secretion of inflammatory mediators, such as nitric oxide (NO), in a dose-dependent manner. Protaetiamycine 9 (25-100 ㎍/ml) effectively downregulated the LPS-induced increase in mRNA and the protein expression of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2), which are involved in the production of inflammatory mediators. Protaetiamycine 9 also suppressed the production and gene expression of pro-inflammatory cytokines, including interleukin (IL)-6 and IL-1β, compared to the presence of LPS alone. Furthermore, protaetiamycine 9 inhibited the degradation of inhibitory kappa B alpha (IκB-α) and the phosphorylation of mitogen-activated protein kinases (MAPKs), such as extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38. In conclusion, these results suggest that protaetiamycine 9 exhibits LPS-mediated inflammatory responses by blocking IκB-α degradation and MAPK phosphorylation.

CLK3 is a Novel Negative Regulator of NF-κB Signaling (NF-κB 신호경로에서 CLK3의 새로운 음성 조절자로서의 기능)

  • Byeol-Eun, Jeon;Chan-Seong, Kwon;Ji-Eun, Lee;Ye-Lin, Woo;Sang-Woo, Kim
    • Journal of Life Science
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    • v.32 no.11
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    • pp.833-840
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    • 2022
  • Chronic inflammation has been shown to be closely associated with tumor development and progression. Nuclear factor kappa B (NF-κB) is composed of a family of five transcription factors. NF-κB signaling plays a crucial role in the inflammatory response and is often found to be dysregulated in various types of cancer, making it an attractive target in cancer therapeutics. In this study, CDC-like kinase 3 (CLK3) was identified as a novel kinase that regulates the NF-κB signaling pathway. Our data demonstrate that CLK3 inhibits the canonical and non-canonical NF-κB pathways. Luciferase assays following the transient or stable expression of CLK3 indicated that this kinase inhibited NF-κB activation mediated by Tumor necrosis factor-alpha (TNFα) and Phorbol 12-myristate 13-acetate (PMA), which are known to activate NF-κB signaling via the canonical pathway. Consistent with data on the ectopic expression of CLK3, CLK3 knockdown using shRNA constructs increased NF-κB activity 1.5-fold upon stimulation with TNFα in HEK293 cells compared with the control cells. Additionally, overexpression of CLK3 suppressed the activation of this signaling pathway induced by NF-κB-inducing kinase (NIK) or CD40, which are well-established activators of the non-canonical pathway. To further examine the negative impact of CLK3 on NF-κB signaling, we performed Western blotting following the TNFα treatment to directly identify the molecular components of the NF-κB pathway that are affected by this kinase. Our results revealed that CLK3 mitigated the phosphorylation/activation of transforming growth factor-α-activated kinase 1 (TAK1), inhibitor of NF-κB kinase alpha/beta (IKKα/α), NF-κB p65 (RelA), NF-κB inhibitor alpha (IκBα), and Extracellular signal-regulated kinase 1/2-Mitogen-activated protein kinase (ERK1/2-MAPK), suggesting that CLK3 inhibits both the NF-κB and MAPK signaling activated by TNFα exposure. Further studies are required to elucidate the mechanism by which CLK3 inhibits the canonical and non-canonical NF-κB pathways. Collectively, these findings reveal CLK3 as a novel negative regulator of NF-κB signaling.

Antioxidative Effects of Tenebrio molitor Larvae Extract Against Oxidative Stress in ARPE-19 Cells (ARPE-19 세포에서 산화적 스트레스에 대한 갈색거저리 추출물의 항산화 효과)

  • Bong Sun, Kim;Ra-Yeong, Choi;Eu-Jin, Ban;Joon Ha, Lee;In-Woo, Kim;Minchul, Seo
    • Journal of Life Science
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    • v.32 no.11
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    • pp.865-871
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    • 2022
  • Tenebrio molitor larvae is well known as edible insect. Then, although it has been widely studied that Tenebrio molitor larvae has various bioactive functions such as antioxidant, anti-wrinkle, and anticancer. Nevertheless, antioxidant effects of Tenebrio molitor larvae water extract (TMH) has not been well described in Adult Retina Pigment Epithelial cell line (ARPE-19). In this study, we demonstrated that antioxidant effects of TMH against H2O2-induced oxidative stress in ARPE-19. Thus, we selected for our studies and performed a series of dose-response assay to determine the working concentration that lead to a consistent and high degree of cytotoxicity, which we defined as the level of H2O2 that killed 40% of the ARPE-19 cells. ARPE-19 cells were pre-treated with various concentrations of TMH (0.1 up to 2 mg/ml) before exposure to 300 µM H2O2. As we expected, TMH effectively prevented ARPE-19 cells from 300 µM H2O2-induced cell death in a dose-dependent manner. Furthermore, TMH inhibited the phosphorylation of mitogen-activated protein kinases (MAPKs) such as extracellular signal regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38. Overall, the inhibitory effects of TMH on H2O2-induced apoptosis and oxidative stress were associated with the protection cleaved caspase-3, Bax, Bcl-2, and HO-1. The TMH suppressed H2O2-induced cell membrane leakage and oxidative stress in ARPE-19 cells. Thus, these results suggest that the TMH plays an important role in antioxidant effect in ARPE-19.

A Study on Jeon Sik(1563~1642)'s Jobok Relics from the 17th Century of the Joseon Dynasty (17세기 전식(全湜, 1563~1642)의 조복 유물 고찰)

  • LEE, Eunjoo;KIM, Migyung
    • Korean Journal of Heritage: History & Science
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    • v.55 no.2
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    • pp.146-165
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    • 2022
  • The purpose of this study is to identify differences in the formative characteristics and system of Jobok by comparing the three relics Ui, Sang, and Daedae, which comprised Jeon-Sik's Jobok, with the data in the literature and five excavated Jobok relics, Sin Kyung-yu, Kwon-Woo, Hwasan-Gun, Milchang-Gun, and Lee Ik-jeong, from the 17th and 18th centuries. Jeon-Sik'sJobok was designated as a Gyeongbuk tangible cultural heritage, Sangju JeonSik Jobok and Crafts, in 2021. The three components of Jeon-Sik's Jobok are valuable as historical data since they are the oldest relics confirming colors. Regrettably, the edging fabric of the Ui made of red twill was mostly lost, with only traces remaining. Based on records, it was presumed that the edging fabric was black. It was confirmed that white decorative lines were yet to be used. In Jeon Sik's Sang, only the three front widths and one rear width remain, but the shape of the four rear widths can be inferred, and the creases were held only at the waist. Eighteenth-century Sang was connected at intervals at the end of the waist. Seventeenth-century Sang was connected with a slight overlapping of the rear Sang below the front Sang; therefore, it is assumed that Jeon Sik's Sang was also connected by overlapping the rear by more or less than 5cm below the front. After Hwasan-gun, the Sang was first made using black lines, then white lines were inserted, and, finally, it was pleated from the waist to the hem. The Daedae made the Yo and the Sin by folding the corners to form a 冂 shape with a single long band. The white Ju(紬) and the green yumunsa were used for the Daedae and the edges. This matches the color of the Daedae seen in the Jobok portraits of Milchang-gun, Lee Ik-jeong, and Jeong Hwi-ryang from the 18th century. In the 17th century, the Daedae made the Yo and the Sin by folding a long band like the Daedae of Jeon-Sik. After the 18th century, the Yo and the Sin were made separately and connected. To tie the Daedae to the waist, thin straps were attached at both ends. The relics of Jeon-Sik can be evaluated as reflecting the 17th-century Jobok system in terms of color and shape. Furthermore, it can be said that they are important historical data complementing the insufficient or inaccurate records of the Gukjoolyeui-seolye and Gyeongguk-daejeon.

Leaching Behavior of Vanadium and Possibility of Recovery of Valuable Metals from VTM Concentrate by Sulfuric Acid Leaching (바나듐함유 티탄철석 정광으로부터 황산 침출법에 의한 바나듐의 침출거동 및 유가금속의 회수가능성)

  • Joo, Sung-Ho;Shin, Dong Ju;Lee, Dongseok;Park, Jin-Tae;Jeon, Hoseok;Shin, Shun Myung
    • Resources Recycling
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    • v.31 no.1
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    • pp.65-77
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    • 2022
  • A study was conducted in Korea on the leaching behavior and possibility of recovery of vanadium and other valuable metals from domestic vanadium titanomagnetite (VTM) by direct acid leaching. In this study, a VTM concentrate containing 0.8% V2O5 was used, and the ratio of magnetite to ilmenite was calculated as 1.9:1 by using the HSC program. The leaching behavior of vanadium from the VTM was similar to that of iron, and it was affected by the concentration of sulfuric acid and temperature. Further, titanium could be leached in the form of TiOSO4 at a temperature higher than 75℃. To improve the leaching efficiency of V, Fe, and Ti in VTM, reductive sulfuric acid and oxidative sulfuric acid leaching were performed. When Na2SO3 was used as a reducing agent, the leaching rate of vanadium was 80% of that in that case of leaching by sulfuric acid. Similarly, the leaching rate of titanium increased from 20% to 50%. When Na2S2O8 was used as an oxidation agent, most of the vanadium was leached, and the main residue found by XRD analysis was ilmenite. In studies on the possibility of recovering valuable metals, the selective extraction of metals is hardly achieved by solvent extraction from oxidation leaching solutions; however, in this study, Cyanex 923, a solvation extractant from reductive leaching solutions, could selectively extract Ti.

Quantitative Electroencephalogram Markers for Predicting Cerebral Amyloid Pathology in Non-Demented Older Individuals With Depression: A Preliminary Study (비치매 노인 우울증 환자에서 대뇌 아밀로이드 병리 예측을 위한 정량화 뇌파 지표: 예비연구)

  • Park, Seon Young;Chae, Soohyun;Park, Jinsick;Lee, Dong Young;Park, Jee Eun
    • Sleep Medicine and Psychophysiology
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    • v.28 no.2
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    • pp.78-85
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    • 2021
  • Objectives: When elderly patients show depressive symptoms, discrimination between depressive disorder and prodromal phase of Alzheimer's disease is important. We tested whether a quantitative electroencephalogram (qEEG) marker was associated with cerebral amyloid-β (Aβ) deposition in older adults with depression. Methods: Non-demented older individuals (≥ 55years) diagnosed with depression were included in the analyses (n = 63; 76.2% female; mean age ± standard deviation 73.7 ± 6.87 years). The participants were divided into Aβ+ (n = 32) and Aβ- (n = 31) groups based on amyloid PET assessment. EEG was recorded during the 7min eye-closed (EC) phase and 3min eye-open (EO) phase, and all EEG data were analyzed using Fourier transform spectral analysis. We tested interaction effects among Aβ positivity, condition (EC vs. EO), laterality (left, midline, or right), and polarity (frontal, central, or posterior) for EEG alpha band power. Then, the EC-to-EO alpha reactivity index (ARI) was examined as a neurophysiological marker for predicting Aβ+ in depressed older adults. Results: The mean power spectral density of the alpha band in EO phase showed a significant difference between the Aβ+ and Aβ- groups (F = 6.258, p = 0.015). A significant 3-way interaction was observed among Aβ positivity, condition, and laterality on alpha-band power after adjusting for age, sex, educational years, global cognitive function, medication use, and white matter hyperintensities on MRI (F = 3.720, p = 0.030). However, post-hoc analyses showed no significant difference in ARI according to Aβ status in any regions of interest. Conclusion: Among older adults with depression, increased power in EO phase alpha band was associated with Aβ positivity. However, EC-to-EO ARI was not confirmed as a predictor for Aβ+ in depressed older individuals. Future studies with larger samples are needed to confirm our results.

The Induction of ROS-dependent Autophagy by Particulate Matter 2.5 and Hydrogen Peroxide in Human Lung Epithelial A549 Cells (미세먼지와 산화적 스트레스에 의한 인간 폐 상피 A549 세포에의 ROS 의존적 자가포식 유도)

  • Park, Beom Su;Kim, Da Hye;Hwangbo, Hyun;Lee, Hyesook;Hong, Su Hyun;Cheong, Jaehun;Choi, Yung Hyun
    • Journal of Life Science
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    • v.32 no.4
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    • pp.310-317
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    • 2022
  • Recently, interest in the harmful factors of particulate matter (PM), a major component of air pollution, has been increasing. In particular, PM2.5 with a diameter of less than 2.5 ㎛ is well known to induce oxidative stress accompanied by autophagy in human lung epithelial cells. However, studies on whether PM2.5 increases autophagy under oxidative stress and whether this process is reactive oxygen species (ROS)-dependent are insufficient. Therefore, in this study, we investigated whether PM2.5 promotes autophagy through the generation of ROS in human alveolar epithelial A594 cells. According to our results, cells co-treated with PM2.5 and hydrogen peroxide (H2O2) showed a lower cell viability than cells treated with each alone, which was associated with increased total and mitochondrial ROS production. The co-treatment of PM2.5 and H2O2 also increased autophagy induction, which was confirmed through Cyto-ID staining, and the expression of autophagy biomarker proteins increased. However, when ROS generation was artificially blocked by N-acetyl-L-cysteine pretreatment, the reduction in cell viability and induction of autophagy by PM2.5 and H2O2 co-treatment were markedly attenuated. Therefore, the present results suggest that PM2.5-induced ROS generation may play a critical role in autophagy induction in A549 cells.

Trend Analysis of Documenting the Gardens of Old Houses with the Measurement Drawings of National Folklore Cultural Heritage (국가민속문화재의 실측도면을 통해 살펴본 고택 정원의 기록화 경향 분석)

  • LIM, Cheyeon;LEE, Jaeyong
    • Korean Journal of Heritage: History & Science
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    • v.55 no.3
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    • pp.46-58
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    • 2022
  • This study analyzed the documentation trend of garden components such as plants, infrastructure, unit facilities, and structures, based on 188 measurement drawings of 94 old houses in a report on the documentation of the national folklore cultural heritage. The findings are as follows. First, it was found that plants and structures continuously appeared as the subject of measurement drawings, while infrastructure was often omitted. It was confirmed that unit facilities, which are smaller than other components, were frequently excluded from the documentation subject as well due to frequent changes such as movement, loss, and expansion. Second, the level of expression in measurement drawings showed different aspects for each component. The unit facilities showed a large change over time with respect to the level of documentation, and the level of documentation was somewhat polarized, particularly toward the latter stage. This suggests that the level of documenting the drawings limited to specific facilities improved, but the overall level of drawings did not improve, such as a lack of diversification of expression techniques suitable for various unit facilities. On the other hand, it was confirmed that the level of documenting the drawings for plants, infrastructure and structures did not change to a significant degree, implying that no improvements were made to the expression of components. Third, as for the technique of detailed expression, in the case of plants, vegetation status was prepared without distinction of old or protected trees that have historical value. Above all, there was no record of the vegetation structure that could help grasp the vegetation landscape of the outer area. As for the infrastructure, there was no consistent expression technique to systematically convey topographic changes such as the height and slope of the land. In addition, since there was no subtype classification defined for unit facilities and structures, there was no subject or method of documentation. This study is meaningful in that it expanded the category of documentation, which has been concentrated on buildings in old houses, to gardens, and called attention to the need for documenting the gardens for the preservation and management of old houses as an integration of the building and outer area.

Comparative Crystal Chemistry of Exchanged by Cs-, Cd-, Pb-, and Sr-synthetic Mordenite Using High Resolution X-ray Powder Diffraction (고분해능 X-선 분말 회절을 이용한 Cs-, Cd-, Pb-, Sr-으로 치환된 합성 모데나이트의 격자상수 비교 연구)

  • Lee, Soojin;Lee, Hyunseung;Seoung, Donghoon;Kim, Pyosang;Kim, Hyeonsu;Lee, Yongmoon
    • Korean Journal of Mineralogy and Petrology
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    • v.35 no.3
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    • pp.345-353
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    • 2022
  • This study aimed to fundamentally understand changes of cell parameters of cation-exchanged mordenites using high resolution X-ray powder diffraction for studies that immobilization of various heavy metal cation using synthesis mordenite (Na6.6Al6.6Si41.4O96·20.4H2O, Na-MOR). As a results of measurement by Thermogravimetric analysis (TGA), it was confirmed that 19.4, 20.4 water molecules per unit cell were present in monovalent-cation substituted MOR (Cs-MOR, Na-MOR), and 21, 23.1, 23.2 water molecules per unit cell were present in divalent-cation substituted MOR (Pb-MOR, Sr-MOR, Cd-MOR). The space group of all the samples were identified as Cmcm belonging to the orthorhombic crystal system. Compared to Na-MOR, starting material, relative peak intensity of (110) and (200) is significantly changed after cation substitution whereas peak position is almost similar. Also, (220) peak that was not found in Na-MOR was clearly observed in Pb-, Cd- and Sr-exchanged MOR. Thus, it was estimated that changes of atomic distribution usually occurred on ab-plane while changes of cell parameters were little. Detailed changes in the cell parameters of cation-exchanged mordenites were derived from whole profile fitting method using the GSAS suite program. Changes in the axial lengths and unit cell volume of cation substitution showed different relationship depending on ionic radius and charge number. In case of monovalent-cation substituted MOR, the length of a-axis increases whereas the length of b- and c-axis decrease by absorbed cation radius. In the case of divalent-cation exchanged MOR, the length of a-axis usually decreases while the length of b- and c-axis increases by cation radius. It was confirmed that unit cell volume of monovalent and divalent cation substituted MORs had an independent tendency by cation radius.