• Title/Summary/Keyword: Marine Model

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Overexpression of Galectin-3 in Macrophages of C57BL/6 mice with Experimental Autoimmune Encephalomyelitis (자가면역성 뇌척수염을 유도한 C57BL/6 마우스 큰포식세포에서의 Galectin-3의 과발현)

  • Kim, Dae Seung;Hwang, Insun;Park, Suk-jae;Ahn, Ginnae;Park, Sang-Joon;Park, Hyun Jeong;Joo, Hong-Gu;Jee, Youngheun
    • Korean Journal of Veterinary Research
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    • v.51 no.2
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    • pp.139-149
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    • 2011
  • Experimental autoimmune encephalomyelitis (EAE) is an inflammatory disease in the murine central nervous system (CNS) and has long been used as an animal model for human multiple sclerosis. Development of EAE requires coordinated expression of a number of genes that are involved in the activation and effector functions of inflammatory cells. Galectin-3 (Gal-3) is a member of the betagalactoside- binding lectin family and plays an important role in inflammatory responses through its functions on cell activation, cell migration or inhibition of apoptosis. We investigated the functional role of Gal-3 in EAE mice following immunization with myelin oligodendrocyte glycoprotein $(MOG)_{35-55}$ peptide. During the peak stage of EAE, the localization of Gal-3 in inflammatory cells markedly increased in subarachnoid membranes and perivascular regions of CNS. In contrast, Gal-3 was weakly detected in cerebrum and spinal of the recovery stage of EAE. Consistent with this finding, western blot analysis revealed that Gal-3 expression was significantly increased at the peak stage while it was slightly decreased at the recovery stage in the CNS. In addition, the population of $CD11b^{+}$ macrophage expressing Gal- 3 in spleen of EAE mice was markedly increased compared with control mice. In fact, most of activated macrophages isolated from spleen of EAE mice expressed Gal-3. Taken together, our results demonstrate that the over-expression of Gal-3 in activated macrophages may play a key role in promoting inflammatory cells in the CNS during EAE.

The Age of the Earth: Reappraisal (지구의 나이: 재평가)

  • Kwon, Sung-Tack
    • The Journal of the Petrological Society of Korea
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    • v.23 no.3
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    • pp.273-277
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    • 2014
  • This paper presents a brief historical review of various attempts to estimate the age of the Earth, and reappraises the study of Patterson (1956) which revealed for the first time that the age of the Earth is $4550{\pm}70Ma$ by measuring Pb isotope ratios of several meteorites and a marine sediment. The standard model for the planetary formation of early solar system is: formation of solid particles condensed from the cooling of hot nebular gas -> formation of planet-sized bodies by accretion of those solid particles. The Moon is supposed to have formed from the accretion of the relicts produced by the collision of proto-Earth with Mars-sized body. It is not easy to pinpoint the age of the Earth, considering the series of events related to the formation of the Earth. So, I propose that the collision age as that of the Earth, since the present status of the Earth is thought to be the direct product of the collision. According to the previous studies, the collision age can be broadly constrained between the age ($4567.30{\pm}0.16Ma$) of the earliest condensates (CAI, calcium-aluminum rich inclusion) of the nebula gas, i.e., the age of the solar system, and the oldest age ($4,456{\pm}40Ma$) among rocks and minerals of the Earth and the Moon. We need more precise estimation of the collision age, since it is important in estimating time scale for the formation of planet-size body and in revealing thermal evolution of magma oceans of the Earth and the Moon presumably developed right after the collision.

Schisandrae Fructus ethanol extract attenuates particulate matter 2.5-induced inflammatory and oxidative responses by blocking the activation of the ROS-dependent NF-κB signaling pathway

  • Lee, Hyesook;Park, Cheol;Kwon, Da Hye;Hwangbo, Hyun;Kim, So Young;Kim, Min Yeong;Ji, Seon Yeong;Kim, Da Hye;Jeong, Jin-Woo;Kim, Gi-Young;Hwang, Hye-Jin;Choi, Yung Hyun
    • Nutrition Research and Practice
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    • v.15 no.6
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    • pp.686-702
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    • 2021
  • BACKGROUND/OBJECTIVES: Schisandrae Fructus, the fruit of Schisandra chinensis Baill., has traditionally been used as a medicinal herb for the treatment of various diseases, and has proven its various pharmacological effects, including anti-inflammatory and antioxidant activities. In this study, we investigated the inhibitory effect of Schisandrae Fructus ethanol extract (SF) on inflammatory and oxidative stress in particulate matter 2.5 (PM2.5)-treated RAW 264.7 macrophages. MATERIALS/METHODS: To investigate the anti-inflammatory and antioxidant effects of SF in PM2.5-stimulated RAW 264.7 cells, the levels of pro-inflammatory mediator such as nitric oxide (NO) and prostaglandin E2 (PGE2), cytokines including interleukin (IL)-6 and IL-1β, and reactive oxygen species (ROS) were measured. To elucidate the mechanism underlying the effect of SF, the expression of genes involved in the generation of inflammatory factors was also investigated. We further evaluated the anti-inflammatory and antioxidant efficacy of SF against PM2.5 in the zebrafish model. RESULTS: The results indicated that SF treatment significantly inhibited the PM2.5-induced release of NO and PGE2, which was associated with decreased inducible NO synthase and cyclooxygenase-2 expression. SF also attenuated the PM2.5-induced expression of IL-6 and IL-1β, reducing their extracellular secretion. Moreover, SF suppressed the PM2.5-mediated translocation of nuclear factor-kappa B (NF-κB) from the cytosol into nuclei and the degradation of inhibitor IκB-α, indicating that SF exhibited anti-inflammatory effects by inhibiting the NF-κB signaling pathway. In addition, SF abolished PM2.5-induced generation of ROS, similar to the pretreatment of a ROS scavenger, but not by an inhibitor of NF-κB activity. Furthermore, SF showed strong protective effects against NO and ROS production in PM2.5-treated zebrafish larvae. CONCLUSIONS: Our findings suggest that SF exerts anti-inflammatory and antioxidant effects against PM2.5 through ROS-dependent down-regulating the NF-κB signaling pathway, and that SF can be a potential functional substance to prevent PM2.5-mediated inflammatory and oxidative damage.

A Study on the Research Topics and Trends in Korean Journal of Remote Sensing: Focusing on Natural & Environmental Disasters (토픽모델링을 이용한 대한원격탐사학회지의 연구주제 분류 및 연구동향 분석: 자연·환경재해 분야를 중심으로)

  • Kim, Taeyong;Park, Hyemin;Heo, Junyong;Yang, Minjune
    • Korean Journal of Remote Sensing
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    • v.37 no.6_2
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    • pp.1869-1880
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    • 2021
  • Korean Journal of Remote Sensing (KJRS), leading the field of remote sensing and GIS in South Korea for over 37 years, has published interdisciplinary research papers. In this study, we performed the topic modeling based on Latent Dirichlet Allocation (LDA), a probabilistic generative model, to identify the research topics and trends using 1) the whole articles, and 2) specific articles related to natural and environmental disasters published in KJRS by analyzing titles, keywords, and abstracts. The results of LDA showed that 4 topics('Polar', 'Hydrosphere', 'Geosphere', and 'Atmosphere') were identified in the whole articles and the topic of 'Polar' was dominant among them (linear slope=3.51 × 10-3, p<0.05) over time. For the specific articles related to natural and environmental disasters, the optimal number of topics were 7 ('Marine pollution', 'Air pollution', 'Volcano', 'Wildfire', 'Flood', 'Drought', and 'Heavy rain') and the topic of 'Air pollution' was dominant (linear slope=2.61 × 10-3, p<0.05) over time. The results from this study provide the history and insight into natural and environmental disasters in KRJS with multidisciplinary researchers.

Design of Physical Layer and Performance Analysis for MX-S2X, Ship Centric Direct Communication with the Mitigation of Multi-path Fading on Sea Environment (해상 다중경로 페이딩 극복을 위한 선박중심 직접통신(MX-S2X) 물리계층 설계 및 성능 분석)

  • Ryu, Hyung-Jick;Yoo, Hae-Sun;Kim, Won-Yong;Kim, Bu-Young;Shim, Woo-Seong
    • Journal of Navigation and Port Research
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    • v.45 no.6
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    • pp.352-359
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    • 2021
  • This paper presents the definition and importance of ship-centric direct communication concerning ship safety of maritime autonomous and unmanned ships. It also proposes the concept of MX-S2X communication based on high frequency for wide-bandwidth technology and describes the design and simulation result for the physical layer of MX-S2X. It considered high-speed communication as well as overcoming maritime multi-path fading required to be resolved in the marine environment. The physical layer of MX-S2X communication was designed to overcome the occurrence of error-floor caused by multi-path fading even with receiving sufficient signal strength. To this purpose, a performance analysis was conducted on the physical layer by applying the channel model of the actual maritime communication environment. As a result of the performance analysis of the MX-S2X physical layer, it was confirmed that the BER error-floor observed in the VDE physical layer test was overcome, and it operated within the SNR 2dB degradation range compared to the AWGN channel. It is expected that this will show enough performance suitable for short-distance ship-centered direct communication and can be used for direct communication of maritime autonomous ships, unmanned ships, and group navigation of themshortly.

A Study on the Flow Analysis for KP505 Propeller Open Water Test (유체기기의 표면 금속코팅 적용에 따른 구조건전성 평가)

  • Lee, Han-Seop;Lim, Byung-Chul;Kim, Min-Tae;Lee, Beom-Soon;Park, Sang-Heup
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.8
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    • pp.23-28
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    • 2019
  • The structural integrity of a surface metal coating was evaluated through numerical results to improve the efficiency and reduce the damage caused by cavitation in ships and marine plants. The goal was to ensure structural strength and performance, even if the thickness of the wing is reduced to reduce the weight of the material and surface coating. Analytical methods were used for four models: a non-coating model, one with the same thickness after coating, one with a thickness reduction of 3% after coating, and one with thickness reduction of 5% after coating. With a thickness reduction of 5% after coating, the stress was increased to 12%, and the safety factor was 0.99%, so the structural integrity was insufficient. However, a better material or a thicker coating could allow a sufficient safety factor to be secured. The structural integrity was improved by the coating, and even when the weight was reduced up to 5%, the structural integrity could be sufficiently secured due to the coating effect.

CFD Simulation of the Self-propulsion of a damaged Car Ferry in Waves (손상된 카페리 선박의 파랑중 자항상태 CFD 해석)

  • Kim, Je-In;Park, Il-Ryong;Kim, Jin;Kim, Kwang-Soo;Kim, Yoo-Chul
    • Journal of the Society of Naval Architects of Korea
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    • v.56 no.1
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    • pp.34-46
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    • 2019
  • This paper provides the numerical results for the self-propulsion performance in waves of a car ferry vessel with damage in one of its twin-screw propulsion systems without flooding the engine room. The numerical simulations were carried out according to the Safe Return to Port (SRtP) regulation made by the Lloyd's register, where the regulation requires that damaged passenger ships should have an ability to return to port with a speed of 6 knots in a Beaufort 8 sea condition. For the validation of the present numerical analysis study, the resistance performance and the self-propulsion performance of the car ferry in intact and damaged conditions in calm water were calculated, which showed a satisfactory agreement with the model test results of Korea Research Institute of Ship and Ocean engineering (KRISO). Finally, the numerical simulation of self-propulsion performance in waves of the damaged car ferry ship was carried out for a normal sea state and for a Beaufort 8 sea state, respectively. The estimated average Brake Horse Power (BHP) for keeping the damaged car ferry ship advancing at a speed of 6 knots in a Beaufort 8 sea state reached about 47% of BHP at MCR condition or about 56% of BHP at NCR condition of the engine determined at the design state. In conclusion, it can be noted that the engine power of the damaged car ferry ship in single propulsion condition is sufficient to satisfy the SRtP requirement.

An Ethanol Extract of the Brown Seaweed Hizikia fusiformis and Its Active Constituent, Fucosterol, Extend the Lifespan of the Nematode Caenorhabditis elegans (갈조류 톳(Hizikia fusiformis)의 에탄올추출물 및 이의 활성성분 fucosterol에 의한 예쁜꼬마 선충의 수명 연장)

  • Oktaviani, Diyah Fatimah;Bae, Young-Seuk;Meinita, Maria Dyah Nur;Moon, Il Soo;Hong, Yong-Ki
    • Journal of Life Science
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    • v.29 no.10
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    • pp.1120-1125
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    • 2019
  • The short-lived nematode Caenorhabditis elegans has been used as a model organism for many studies, including lifespan extension. To screen common seaweeds for natural anti-aging agents, the lifespan of C. elegans (N2 wild-type strain) was measured by its hatch rate, growth rate, survival rate, chemotaxis, brood size, and egg-laying time after exposure to nematode growth medium (NGM) containing seaweed extracts. Approximately 30 animals synchronized at the first larval stage were incubated until they reached their adult stages before laying their eggs and were transferred to fresh NGM every 3 days. We also identified the major active compound from the seaweed by gas chromatography-mass spectrometry and tested its optimal dose for longevity. Of 13 common seaweed species, an ethanol extract of the brown seaweed Hizikia fusiformis showed the greatest effect on hatching, growth, and survival rates. The lifespan of C. elegans was significantly expanded 1.54-fold and 1.23-fold in the presence of the ethanol extract (0.05 mg/ml) and the main active component, fucosterol (0.05 mg/ml), respectively. Exposure to the ethanol extract also increased chemotaxis 1.13-fold, decreased brood size 0.74-fold, and shortened egg-laying time 0.96-fold. These results suggest that the aquaculturable H. fusiformis may be a promising source of a diet supplement to support health care.

Estimation of drift force by real ship using multiple regression analysis (다중회귀분석에 의한 실선의 표류력 추정)

  • AHN, Jang-Young;KIM, Kwang-il;KIM, Min-Son;LEE, Chang-Heon
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.57 no.3
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    • pp.236-245
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    • 2021
  • In this study, a drifting test using a experimental vessel (2,966 tons) in the northern waters of Jeju was carried out for the first time in order to obtain the fundamental data for drift. During the test, it was shown that the average leeway speed and direction by GPS position were 0.362 m/s and 155.54° respectively and the leeway rate for wind speed was 8.80%. The analysis of linear regression modes about leeway speed and direction of the experimental vessel indicated that wind or current (i.e. explanatory variable) had a greater influence upon response variable (e.g. leeway speed or direction) with the speed of the wind and current rather than their directions. On the other hand, the result of multiple regression model analysis was able to predict that the direction was negative, and it was demonstrated that predicted values of leeway speed and direction using an experimental vessel is to be more influential by current than wind while the leeway speed through variance and covariance was positive. In terms of the leeway direction of the experimental vessel, the same result of the leeway speed appeared except for a possibility of the existence of multi-collinearity. Then, it can be interpreted that the explanatory variables were less descriptive in the predicted values of the leeway direction. As a result, the prediction of leeway speed and direction can be demonstrated as following equations. Ŷ1= 0.4031-0.0032X1+0.0631X2-0.0010X3+0.4110X4 Ŷ2= 0.4031-0.6662X1+27.1955X2-0.6787X3-420.4833X4 However, many drift tests using actual vessels and various drifting objects will provide reasonable estimations, so that they can help search and rescue fishing gears as well.

Development of online drone control management information platform (온라인 드론방제 관리 정보 플랫폼 개발)

  • Lim, Jin-Taek;Lee, Sang-Beom
    • Journal of the Institute of Convergence Signal Processing
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    • v.22 no.4
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    • pp.193-198
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    • 2021
  • Recently, interests in the 4th industry have increased the level of demand for pest control by farmers in the field of rice farming, and the interests and use of agricultural pest control drones. Therefore, the diversification of agricultural control drones that spray high-concentration pesticides and the increase of agricultural exterminators due to the acquisition of national drone certifications are rapidly developing the agricultural sector in the drone industry. In addition, as detailed projects, an effective platform is required to construct large-scale big data due to pesticide management, exterminator management, precise spraying, pest control work volume classification, settlement, soil management, prediction and monitoring of damages by pests, etc. and to process the data. However, studies in South Korea and other countries on development of models and programs to integrate and process the big data such as data analysis algorithms, image analysis algorithms, growth management algorithms, AI algorithms, etc. are insufficient. This paper proposed an online drone pest control management information platform to meet the needs of managers and farmers in the agricultural field and to realize precise AI pest control based on the agricultural drone pest control processor using drones and presented foundation for development of a comprehensive management system through empirical experiments.