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Pathophysiological Regulation of Vascular Smooth Muscle Cells by Prostaglandin F2α-dependent Activation of Phospholipase C-β3 (Prostaglandin F2α 의존적 phospholipase C-β3 활성화에 의한 혈관평활근세포의 병태생리 조절 연구)

  • Kang, Ki Ung;Oh, Jun Young;Lee, Yun Ha;Lee, Hye Sun;Jin, Seo Yeon;Bae, Sun Sik
    • Journal of Life Science
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    • v.28 no.12
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    • pp.1516-1522
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    • 2018
  • Atherosclerosis is an obstructive vessel disease mainly caused by chronic arterial inflammation to which the proliferation and migration of vascular smooth muscle cells (VSMCs) is the main pathological response. In the present study, the primary responsible inflammatory cytokine and its signaling pathway was investigated. The proliferation and migration of VSMCs was significantly enhanced by the prostaglandin $F_{2{\alpha}}$ ($PGF_{2{\alpha}}$), while neither was affected by tumor necrosis factor ${\alpha}$. Prostacyclin $I_2$ was seen to enhance the proliferation of VSMCs while simultaneously suppressing their migration. Both prostaglandin $D_2$ and prostaglandin $E_2$ significantly enhanced the migration of VSMCs, however, proliferation was not affected by either of them. The proliferation and migration of VSMCs stimulated by $PGF_{2{\alpha}}$ progressed in a dose-dependent manner; the $EC_{50}$ value of both proliferation and migration was $0.1{\mu}M$. VSMCs highly expressed the phospholipase isoform $C-{\beta}3$ ($PLC-{\beta}3$) while others such as $PLC-{\beta}1$, $PLC-{\beta}2$, and $PLC-{\beta}4$ were not expressed. Inhibition of the PLCs by U73122 completely blocked the $PGF_{2{\alpha}}$-induced migration of VSMCs, and, in addition, silencing $PLC-{\beta}3$ significantly diminished the $PGF_{2{\alpha}}$-induced proliferation and migration of VSMCs. Given these results, we suggest that $PGF_{2{\alpha}}$ plays a crucial role in the proliferation and migration of VSMCs, and activation of $PLC-{\beta}3$ could be involved in their $PGF_{2{\alpha}}$-dependent migration.

Technological Diversities Observed in Bronze Objects of the Late Goryo Period - Case Study on the Bronze Bowls Excavated from the Burial Complex at Deobu-gol in Goyang - (고려 말 청동용기에 적용된 제작기술의 다양성 연구 - 고양 더부골 고분군 출토 청동용기를 중심으로 -)

  • Jeon, Ik Hwan;Lee, Jae Sung;Park, Jang Sik
    • Korean Journal of Heritage: History & Science
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    • v.46 no.1
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    • pp.208-227
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    • 2013
  • Twenty-seven bronze bowls excavated from the Goryo burial complex at Deobu-gol were examined for their microstructure and chemical composition to characterize the bronze technology practiced by commoners at the time. Results showed that the objects examined can be classified into four groups: 1) objects forged out of Cu-near 22%Sn alloys and then quenched; 2) objects cast from Cu-below 10% Sn alloys containing lead; 3) objects cast from Cu-10%~20% Sn alloys containing lead and then quenched; 4) objects forged out of Cu-10~20% Sn alloys containing lead and then quenched. This study revealed that the fabrication technique as determined by alloy compositions plays an important role in bronze technology. The use of lead was clearly associated with the selection of quenching temperatures, the character of inclusions and the color characteristics of bronze surfaces. It was found that the objects containing lead were quenched at temperatures of $520^{\circ}{\sim}586^{\circ}C$ while those without lead were quenched at the range of $586^{\circ}{\sim}799^{\circ}C$. The presence of selenium in impurity inclusions was detected only in alloys containing lead, suggesting that the raw materials, Cu and Sn, used in making the lead-free alloys for the first group were carefully selected from those smelted using ores without lead contamination. Furthermore, the addition of lead was found to have significant effects on the color characteristics of the surface of bronze alloys when they are subjected to corrosion during interment. In leaded alloys, corrosion turns the surface light green or dark green while in unleaded alloys, corrosion turns the surface dark brown or black. It was found that in fabrication, the wall thickness of the bronze bowls varies depending on the application of quenching; most of the quenched objects have walls 1mm thick or below while those without quenching have walls 1mm thick or above. Fabrication techniques in bronze making usually reflect social environments of a community. It is likely that in the late Goryo period, experiencing lack of skilled bronze workers, the increased demand for bronze was met in two ways; by the use of chief lead instead of expensive tin and by the use of casting suitable for mass production. The above results show that the Goryo bronze workers tried to overcome such a resource-limited environment through technological innovations as apparent in the use of varying fabrication techniques for different alloys. Recently, numerous bronze objects are excavated and available for investigation. This study shows that with the use of proper analytical techniques they can serve as a valuable source of information required for the characterization of the associated technology as well as the social environment leading to the establishment of such technology.

Fabrication of Strain Sensor Based on Graphene/Polyurethane Nanoweb and Respiration Measurement (그래핀/폴리우레탄 나노웹 기반의 스트레인센서 제작 및 호흡측정)

  • Lee, Hyocheol;Cho, Hyeon-seon;Lee, Eugene;Jang, Eunji;Cho, Gilsoo
    • Science of Emotion and Sensibility
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    • v.22 no.1
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    • pp.15-22
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    • 2019
  • The purpose of this study is to develop a strain sensor based on a nanoweb by applying electrical conductivity to a polyurethane nanoweb through the use of Graphene. For this purpose, 1% Graphene ink was pour-coated on a polyurethane nanoweb and post-treated with PDMS (Polydimethylsiloxane) to complete a wearable strain sensor. The surface characteristics of the specimens were evaluated using a field emission scanning electron microscope (FE-SEM) to check whether the conductive material was well coated on the surface of the specimen. Electrical properties of the specimens were measured by using a multimeter to measure the linear resistance of the specimen and comparing how the line resistance changes when 5% and 10% of the specimens are tensioned, respectively. In order to evaluate the performance of the specimen, the gauge factor was obtained. The evaluation of the clothing was performed by attaching the completed strain sensor to the dummy and measuring the respiration signal according to the tension using MP150 (Biopac system Inc., USA) and Acqknowledge (ver. 4.2, Biopac system Inc., U.S.A.). As a result of the evaluation of the surface characteristics, it was confirmed that all the conductive nanoweb specimen were uniformly coated with the Graphen ink. As a result of measuring the resistance value according to the tensile strength, the specimen G, which was treated with just graphene had the lowest resistance value, the specimen G-H had the highest resistance value, and the change of the line resistance value of the specimen G and the specimen G-H is increased to 5% It is found that it increases steadily. Unlike the resistance value results, specimen G showed a higher gauge rate than specimen G-H. As a result of evaluation of the actual clothes, the strain sensor made using the specimen G-H measured the stable peak value and obtained a signal of good quality. Therefore, we confirmed that the polyurethane nanoweb treated with Graphene ink plays a role as a breathing sensor.

An Analysis on the Survey of the Cultural Heritage Committee (문화재위원회 설문조사 분석)

  • Kim, Hong-real
    • Korean Journal of Heritage: History & Science
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    • v.37
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    • pp.405-444
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    • 2004
  • The Cultural Heritage Committee is an advisory committee established under the Cultural Heritage Administration with the aim of carrying out examination and deliberation on preservation, management and use of cultural heritage. The Cultural Heritage Administration is the highest administrative organization in terms of Korean cultural heritage. It was founded to produce and execute policies on cultural heritage, an important task that requires a high level of specialized knowledge, skills and academic expertise. It involves in-depth investigation and consultation of experts in the field of cultural heritage. An organization consisting of distinguished experts, the Cultural Heritage Committee plays an important role in policymaking on cultural heritage of Korea. The Korean government established the Bureau of Cultural Heritage in October 1961, and enacted provisions (as a presidential decree) on the organization on March 27, 1962, according to the Cultural Heritage Act established on January 10 of the same year. The Cultural Heritage Committee was opened as a deliberation committee according to the law, on which currently 90 members serve in 8 subcommittees. The term of office of a committees member is two years. The deliberation of the committee, which covers the entire range of cultural heritage, including their designation and cancellation, is normally concluded by the deliberation and decision of each subcommittee. This study aims to analyze of the survey of the Cultural Heritage Committee as the highest organ for the deliberation of policies on the matters of cultural heritage. The subject of the analysis in this study is a questionnaire survey that was conducted between Oct. 20 and Nov. 29, 2003, of 116 former and current members of the committee.

Function and Use Evaluation of 'Classification & Disposal Schedule Management' in the Standard Records Management System (표준 기록관리시스템의 '기준관리' 기능 및 이용 평가)

  • Chung, Sang-hee
    • The Korean Journal of Archival Studies
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    • no.37
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    • pp.189-237
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    • 2013
  • Since central governments began to establish and use the Standard Records Management System(RMS) in 2007, more and more local governments and other public organizations have constructed RMS. RMS is the essential tool for records management in electronic environments, but it is not known how well the functions of RMS reflect standards and practice related records management or how many records managers use RMS in performing their works. This paper deals with analyzing the evaluation of 'classification & disposal schedule management' function in RMS. 'Classification & disposal schedule management' function has 4 subfunctions of review of classification & preservation period, management of the schedule items, assignment of classification scheme and reclassification. Classification and disposal schedule is at the heart of intellectual control of records and core area of records management. So it is important to analyze whether this function plays well a role in RMS or not. This research carried out evaluation of function and use about classification & disposal schedule management in RMS. Functional evaluation is to compare and analyze how well RMS meets the functional requirements which home and foreign standards give. Use evaluation is to investigate how records managers use RMS in accomplishing their task of managing classification & disposal schedule and to look into what is the problem with the use. This paper could get the implications through the survey of records managers who are working at central governments, regional local governments and basic local governments. And these implications are considered in institutional, functional, use and administrative aspect. It is important to communicate with stakeholders so that 'classification & disposal schedule management' function, further, all functions of the RMS in practice of records management could be used smoothly. Users of RMS have to raise demands or call for technical solutions of the problems which come up in use, while RMS developers and administrators must make more of an effort to satisfy their demands, reflect them on the RMS and enhance the system.

Role of Dual Oxidase 2 in Reactive Oxygen Species Production Induced by Airborne Particulate Matter PM10 in Human Epidermal Keratinocytes (인간 표피 각질형성세포에서 대기 미립자 물질 PM10에 의해 유도되는 반응성 산소종의 생성에서 Dual oxidase 2의 역할)

  • Seok, Jin Kyung;Choi, Min A;Ha, Jae Won;Boo, Yong Chool
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.45 no.1
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    • pp.57-67
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    • 2019
  • Particulate matters with a diameter of < $10{\mu}m$ (PM10) exert oxidative stress and inflammatory events in various organs. The purpose of this study was to examine the molecular mechanism of reactive oxygen species (ROS) production induced by PM10 in the human epidermal keratinocytes (HEKs). When cultured HEKs were exposed to PM10, ROS production was induced and it was inhibited by apocynin, an antioxidant. The mRNA expression of NADPH oxidase (NOX) family was analyzed in order to examine their role in PM10-induced ROS production. PM10 increased the mRNA expression of NOX1, NOX2, dual oxidase (DUOX) 1 and DUOX2. HEKs expressed DUOX1 and DUOX2 at higher levels compared to other NOXs. The mRNA expression of dual oxidase maturation factors, DUOXA1 and DUOXA2, was also increased by PM10. We examined whether these calcium-dependent enzymes, DUOX1 and DUOX2, mediate the PM10-induced ROS production. A selective intracellular calcium chelator, BAPTA-AM, attenuated ROS production induced by PM10 or calcium ionophore A23187. The small intereference RNA (siRNA)-mediated down-regulation of DUOX2, but not DUOX1, attenuated the ROS production induced by PM10. PM10 increased the expression of inflammatory cytokines such as interleukin $(IL)-1{\beta}$, IL-6, IL-8 and interferon $(IFN)-{\gamma}$. SiRNA-mediated down-regulation of DUOX2 suppressed the PM10-induced expression of $IFN-{\gamma}$ but not other cytokines. This study suggests that DUOX2 plays a crucial role in ROS production and inflammatory response in PM10-exposed keratinocytes.

Effect of Composition on Isotropic Chemical Shift of Na Silicate and Aluminosilicate Glasses Using Solid State NMR (고상 핵자기공명 분광분석을 이용한 비정질 Na 규산염 및 알루미노규산염 내 조성에 따른 등방성 화학적 차폐 변화 규명)

  • Park, Sun Young;Lee, Sung Keun
    • Journal of the Mineralogical Society of Korea
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    • v.32 no.1
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    • pp.41-49
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    • 2019
  • Probing the Na environments in Na silicate and aluminosilicate glasses is essential to the macroscopic properties of melts in the Earth. In particular, exploring the atomic structure of Na silicate and aluminosilicate glasses reveals Na-O distance, which plays an important role in transport properties of melts. Here we report the local environment around Na using $^{23}Na$ magic angle spinning (MAS) NMR. We also obtain $^{23}Na$ isotropic chemical shift (${\delta}_{iso}$) of Na silicate and aluminosilicate glasses with varying composition using Dmfit program. The Q mas 1/2 model simulates the experimental results with three simulated peaks while the CzSimple model simulates with one peak. The ${\delta}_{iso}$ decreases with increasing $SiO_2$ content in Na silicate and aluminosilicate glasses. The ${\delta}_{iso}$ increases with increasing $Na_2O$ content in Na-Ca silicate and Na aluminosilicate glasses when the $SiO_2$ content is fixed. Considering the ${\delta}_{iso}$ of Na aluminosilicate glasses available in the previous studies, together with the current simulation results, we confirm that the ${\delta}_{iso}$ has positive correlation with Al / (Al + Si). Those experimental results were reproduced better using Q mas 1/2 model. The disorder of Na in Na silicate and aluminosilicate glasses can be revealed through the simulation of 1D $^{23}Na$ MAS NMR spectra using Dmfit program in a short time.

Coarse Woody Debris (CWD) Respiration Rates of Larix kaempferi and Pinus rigida: Effects of Decay Class and Physicochemical Properties of CWD (일본잎갈나무와 리기다소나무 고사목의 호흡속도: 고사목의 부후등급과 이화학적 특성의 영향)

  • Lee, Minkyu;Kwon, Boram;Kim, Sung-geun;Yoon, Tae Kyung;Son, Yowhan;Yi, Myong Jong
    • Journal of Korean Society of Forest Science
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    • v.108 no.1
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    • pp.40-49
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    • 2019
  • Coarse woody debris (CWD), which is a component of the forest ecosystem, plays a major role in forest energy flow and nutrient cycling. In particular, CWD isolates carbon for a long time and is important in terms of slowing the rate of carbon released from the forest to the atmosphere. Therefore, this study measured the physiochemical characteristics and respiration rate ($R_{CWD}$) of CWD for Larix kaempferi and Pinus rigida in temperate forests in central Korea. In summer 2018, CWD samples from decay class (DC) I to IV were collected in the 14 forest stands. $R_{CWD}$ and physiochemical characteristics were measured using a closed chamber with a portable carbon dioxide sensor in the laboratory. In both species, as CWD decomposition progressed, the density ($D_{CWD}$) of the CWD decreased while the water content ($WC_{CWD}$) increased. Furthermore, the carbon concentrations did not significantly differ by DC, whereas the nitrogen concentration significantly increased and the C/N ratio decreased. The respiration rate of L. kaempferi CWD increased significantly up to DC IV, but for P. rigida it increased to DC II and then unchanged for DC II-IV. Accordingly, except for carbon concentration, all the measured characteristics showed a significant correlation with $R_{CWD}$. Multiple linear regression showed that $WC_{CWD}$ was the most influential factor on $R_{CWD}$. $WC_{CWD}$ affects $R_{CWD}$ by increasing microbial activity and is closely related to complex environmental factors such as temperature and light conditions. Therefore, it is necessary to study their correlation and estimate the time-series pattern of CWD moisture.

Implication of High Mobility Group Box 1 (HMGB1) in Multicellular Tumor Spheroid (MTS) Culture-induced Epithelial-mesenchymal Transition (Multicellular tumor spheroid (MTS) 배양에 의한 EMT에서 HMGB1의 역할)

  • Lee, Su Yeon;Ju, Min Kyung;Jeon, Hyun Min;Kim, Cho Hee;Park, Hye Gyeong;Kang, Ho Sung
    • Journal of Life Science
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    • v.29 no.1
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    • pp.9-17
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    • 2019
  • As tumors develop, they encounter microenvironmental stress, such as hypoxia and glucose depletion, due to poor vascular function, thereby leading to necrosis, which is observed in solid tumors. Necrotic cells are known to release cellular cytoplasmic contents, such as high mobility group box 1 (HMGB1), into the extracellular space. The release of HMGB1, a proinflammatory and tumor-promoting cytokine, plays an important role in promoting inflammation and metabolism during tumor development. Recently, HMGB1 was shown to induce the epithelial-mesenchymal transition (EMT) and metastasis. However, the underlying mechanism of the HMGB1-induced EMT, invasion, and metastasis is unclear. In this study, we showed that noninvasive breast cancer cells MCF-7 formed tightly packed, rounded spheroids and that the cells in the inner regions of a multicellular tumor spheroid (MTS), an in vitro model of a solid tumor, led to necrosis due to an insufficient supply of O2 and glucose. In addition, after 7 d of MTS culture, the EMT was induced via the transcription factor Snail. We also showed that HMGB1 receptors, including RAGE, TLR2, and TLR4, were induced by MTS culture. RAGE, TLR2, and TLR4 shRNA inhibited MTS growth, supporting the idea that RAGE/TLR2/TLR4 play critical roles in MTS growth. They also prevented MTS culture-induced Snail expression, pointing to RAGE/TLR2/TLR4-dependent Snail expression. RAGE, TLR2, and TLR4 shRNA suppressed the MTS-induced EMT. In human cancer tissues, high levels of RAGE, TLR2, and TLR4 were detected. These findings demonstrated that the HMGB-RAGE/TLR2/TLR4-Snail axis played a crucial role in the growth of the MTS and MTS culture-induced EMT.

Automatic Fracture Detection in CT Scan Images of Rocks Using Modified Faster R-CNN Deep-Learning Algorithm with Rotated Bounding Box (회전 경계박스 기능의 변형 FASTER R-CNN 딥러닝 알고리즘을 이용한 암석 CT 영상 내 자동 균열 탐지)

  • Pham, Chuyen;Zhuang, Li;Yeom, Sun;Shin, Hyu-Soung
    • Tunnel and Underground Space
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    • v.31 no.5
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    • pp.374-384
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    • 2021
  • In this study, we propose a new approach for automatic fracture detection in CT scan images of rock specimens. This approach is built on top of two-stage object detection deep learning algorithm called Faster R-CNN with a major modification of using rotated bounding box. The use of rotated bounding box plays a key role in the future work to overcome several inherent difficulties of fracture segmentation relating to the heterogeneity of uninterested background (i.e., minerals) and the variation in size and shape of fracture. Comparing to the commonly used bounding box (i.e., axis-align bounding box), rotated bounding box shows a greater adaptability to fit with the elongated shape of fracture, such that minimizing the ratio of background within the bounding box. Besides, an additional benefit of rotated bounding box is that it can provide relative information on the orientation and length of fracture without the further segmentation and measurement step. To validate the applicability of the proposed approach, we train and test our approach with a number of CT image sets of fractured granite specimens with highly heterogeneous background and other rocks such as sandstone and shale. The result demonstrates that our approach can lead to the encouraging results on fracture detection with the mean average precision (mAP) up to 0.89 and also outperform the conventional approach in terms of background-to-object ratio within the bounding box.