• Title/Summary/Keyword: 해석적 연구

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Inhibition of Phorbol 12-myristate-13-acetate Induced Cyclooxygenase-2 Activity by Three-step Fermented Soybeans (PMA에 의해 유도된 cycooxygenase-2 활성에 대한 새로운 발효법에 의한 대두산물의 억제 효능)

  • Park, Cheol;Lee, Jeong-Ok;Ryu, Chung-Ho;Choi, Yung-Hyun
    • Journal of Life Science
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    • v.18 no.2
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    • pp.180-186
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    • 2008
  • In this study, we examined the effects of the fermented soybeans by Bacillus subtilis (FSB) and the novel three-step fermented soybeans (TFS) on the expression and activity of COX-2 in human leukemic U937 cell model. Treatment of phorbol 12-myristate 13-acetate (PMA) significantly induced pro-inflammatory mediators such as COX-2 expression and prostaglandin $E_2\;(PGE_2)$ production, whereas the levels of COX-1 remained unchanged. However, pre-treatment with FSB and TFS significantly attenuated the PMA-induced COX-2 protein as well as mRNA, which was associated with inhibition of $PGE_2$ production. Moreover, TFS exerts a much better inhibitory activity than FSB against PMA-induced activation of COX-2 and production of $PGE_2$ in U937 cells. Taken together, these findings provide important new insights into the possible molecular mechanisms of the anti-inflammatory activity of FSB and TFS.

An Experimental Study on the Flexural Behavior of the Round Concrete Panels according to the Evaluation Method of Biaxial Flexural Tensile Strengths (휨인장강도 평가 방법에 따른 콘크리트 원형패널의 휨거동에 관한 실험적 연구)

  • Kim, Ji-Hwan;Zi, Goang-Seup
    • Journal of the Korea Concrete Institute
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    • v.23 no.4
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    • pp.479-486
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    • 2011
  • In this study, we conducted experiment and finite element analysis on the flexural behavior of the round concrete panels according to the evaluation method of biaxial flexural tensile strengths. The Round Panel Test (RPT) and the Biaxial Flexure Test (BFT) were used to determine the biaxial flexural strength of round plain concrete panels. In order to understand the stress distribution on the panels, we measured load-strain relationship at the center of the panels' bottom surface. Test results show that fracture pattern in RPT and BFT panels are similar, and the tensile stress distribution is uniform in all directions at the center of the bottom surface of the panels for both RPT and BFT. The distribution of stresses in two test specimens coincided with the analysis result. The average biaxial flexural strength of RPT is about 29% greater than those of the BFT. The coefficient of variations (COV) of the RPT and BFT for the biaxial flexure strength is 8%, 6%, respectively, which indicates that BFT method is useful and reliable for determining biaxial flexural strengths of the concrete.

Field Load Test Results and Suggestion of Simple Settlement Estimation Method for Granular Compaction Piles (조립토 다짐말뚝에 대한 현장재하시험 결과 및 간편 침하량 산정방법의 제시)

  • Hwang Jung-Soon;Kim Hong-Taek;Kim Jung-Ho;Lee Sang-Kyung;Lee Hyung-Kyu
    • Journal of the Korean Geotechnical Society
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    • v.21 no.3
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    • pp.159-168
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    • 2005
  • In the previous studies, settlement behaviors of granular compaction piles have generally been analyzed with an evaluation of the settlement reduction factor based on tile load-sharing ratio and the replacement ratio. In this approach, however, since the reinforced ground with granular compaction piles is simplified as the composite ground, only the difference of a relative vertical strength between piles and soils is taken into account without reflecting lateral behaviors of granular compaction piles. In the companion research paper, the method of estimating the settlement of granular compaction piles was proposed by synthetically considering a vertical strength of the ground, lateral behaviors of granular compaction piles, the strength of pile materials, a pile diameter, and an installation distance of the pile. In the presented study, to validate a propriety of the previously proposed method, large scale field load tests and three dimensional numerical analyses are performed. The results are analyzed in detail and compared with the predicted settlements by the proposed method. Finally, a simple method to estimate the settlement of granular compaction piles is suggested for an easy application of the practical design.

Variation in the Lipid Class and Fatty Acid Composition of Thraustochytrium aureum ATCC 34304 (Thraustochytrium aureum ATCC 34304의 지질 및 지방산 조성 변화)

  • Jeh, Eun-Jin;Song, Sang-Kyu;Seo, Jeong-Woo;Hur, Byung-Ki
    • KSBB Journal
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    • v.22 no.1
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    • pp.37-42
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    • 2007
  • The heterotrophic marine algae Thraustochytrium aureum ATCC 34304 produces substantial amount of polyunsaturated fatty acids (PUFAs), especially docosahexaenoic acid (DHA). In this study, changes in the lipid and fatty acid compositions of Thraustochytrium aureum ATCC 34304 were investigated according to the growth stage. The major lipids of Thraustochytrium aureum ATCC 34304 were found to be composed of triacylglyceride (TAG), phospholipid (PL), and sterol (ST). The content of triacylglyceride increased during the exponential phase of cell growth, but the content of phospholipid decreased. The composition of total polyunsaturated fatty acids decreased from 60.3% to 45.3% and that of docosahexaenoic acid from 42.1% to 33.9% in the triacylglyceride. The composition of total saturated fatty acids, however, increased from 24.9% to 27.8%. The content of total polyunsaturated fatty acids decreased greatly from 48.0% to 17.5% but the decrease in the content of saturated fatty acids was slight in phospholipid.

Chronological Study on the Deposits by Indicators of Woody Plants (수목지표(樹木指標)에 의한 하상퇴적지(河床堆積地)의 연대학적(年代學的) 연구(硏究))

  • Chun, Kun Woo
    • Journal of Korean Society of Forest Science
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    • v.81 no.3
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    • pp.263-272
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    • 1992
  • In a torrential river, the flow of debris forms deposits in the river bed, which show the characteristics of the channel bed movement in the watershed. The annual rings of the trees, in the natural evenaged forests on the deposits, indicate when each deposit occurred. Based on the topographical and vegetational indicators on the sediment of Yongcheon and Yeounae rivers, the movement occurrence years were estimated. 1. The cross sectional shapes of deposits in torrential river are in tiers and even-aged forests tend to establish on each tier. 2. Generally the older the forest age is, the higher the height of step from the lowest base tend to become, which indicates discrete movement in magnitude and frequency. 3. The ages of trees indicate the year when deposition occurred, and so may be useful as plant indicator to get spatial-temporal information of deposits. 4. The deposits volumes(F. V.) were dependent on the age distribution of deposits in length, average width and average height. And the average width and the average height of deposits were increasing with the age.

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A Study on Applicability of Pre-splitting Blasting Method According to Joint Frequency Characteristics in Rock Slope (암반사면의 절리빈도 특성에 따른 프리스플리팅 발파공법의 적용성 연구)

  • Kim, Shin;Lee, Seung-Joong;Choi, Sung-O.
    • Explosives and Blasting
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    • v.28 no.2
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    • pp.1-16
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    • 2010
  • This study focuses on the phenomenon that the blast damaged zone developed on rock slope surfaces can be affected by joint characteristics rather than by explosive power when the pre-splitting is applied to excavate a jointed rock slope. The characteristics of rock joints on a slope were investigated and categorized them into 4 cases. Also an image processing system has been used for comparing the distribution pattern of rock blocks. From this investigation, it was found that the rock blocks bigger than 2,000 mm occupied 42% in the case of single joint set and it showed the well efficiency of pre-splitting blast. In cases of 2~3 parallel joint sets and 2~3 intersecting joint sets are developed on rock surfaces, the rock blocks in the range of 1,000~2,000 mm occupied 43.6% and 35.8%, respectively, and it showed that the efficiency of pre-splitting was decreased. When more than 3 joint sets are randomly developed, however, the rock blocks in the range of 250~500 mm occupied 35% and there was no block bigger than 1,000 mm. This denotes that the blasting with pre-splitting was not effective. The numerical analysis using PFC2D showed that the blast damaged zone in a rock mass could be directly influenced by the pre-splitting. It is, therefore, required to investigate the discontinuity pattern on rock surfaces in advance, when the pre-splitting method is applied to excavate jointed rock slopes and to apply a flexible blating design with a consideration of the joint characteristics.

In-situ Phase Transition Study of Minerals using Micro-focusing Rotating-anode X-ray and 2-Dimensional Area Detector (집속 회전형 X-선원과 이차원 검출기를 이용한 광물의 실시간 상전이 연구)

  • Seoung, Dong-Hoon;Lee, Yong-Moon;Lee, Yong-Jae
    • Economic and Environmental Geology
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    • v.45 no.2
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    • pp.79-88
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    • 2012
  • The increased brightness and focused X-ray beams now available from laboratory X-ray sources facilitates a variety of powder diffraction experiments not practical using conventional in-house sources. Furthermore, the increased availability of 2-dimensional area detectors, along with implementation of improved software and customized sample environmental cells, makes possible new classes of in-situ and time-resolved diffraction experiments. These include phase transitions under variable pressure- and temperature conditions and ion-exchange reactions. Examples of in-situ and time-resolved studies which are presented here include: (1) time-resolved data to evaluate the kinetics and mechanism of ion exchange in mineral natrolite; (2) in-situ dehydration and thermal expansion behaviors of ion-exchanged natrolite; and (3) observations of the phases forming under controlled hydrostatic pressure conditions in ion-exchanged natrolite. Both the quantity and quality of the in-situ diffraction data are such to allow evaluation of the reaction pathway and Rietveld analysis on selected dataset. These laboratory-based in-situ studies will increase the predictability of the follow-up experiments at more specialized beamlines at the synchrotron.

Sanguinarine Induces Apoptosis in Human Hepatocellular Carcinoma HepG2 Cells through the Generation of ROS and Modulation of Akt/ERK Signaling Pathways (HepG2 인체 간암세포의 ROS 생성 및 ERK/Akt 신호전달 경로 조절을 통한 sanguinarine의 apoptosis 유도)

  • Hwang, Ju Yeong;Cho, Yung Hyun
    • Journal of Life Science
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    • v.25 no.9
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    • pp.984-992
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    • 2015
  • Sanguinarine is a benzophenanthridine alkaloid originally isolated from the roots of Sanguinaria canadensis. It has multiple biological activities (e.g., antioxidant and antiproliferative) and immune-enhancing potential. In this study, we explored the proapoptotic properties and modes of action of sanguinarine in human hepatocellular carcinoma HepG2 cells. Our results revealed that sanguinarine inhibited HepG2 cell growth and induced apoptosis in a dose-dependent manner. The induction of apoptosis by sanguinarine was associated with the up-regulation of Fas and Bax, the release of cytochrome c from the mitochondria to the cytosol, and the loss of the mitochondrial membrane potential. In addition, sanguinarine activated caspase-9 and -8, initiator caspases of the intrinsic and death extrinsic pathways, respectively, and caspase-3, accompanied by proteolytic degradation of poly (ADP-ribose) polymerase. Sanguinarine also triggered the generation of reactive oxygen species (ROS). The elimination of ROS by N-acetylcysteine reversed sanguinarine-induced apoptosis. Furthermore, sanguinarine induced the dephosphorylation of Akt and the phosphorylation of mitogen-activated protein kinases, including extracellular signal-regulated kinase (ERK), c-jun N-terminal kinase (JNK), and p38. The growth inhibition was enhanced by the combined treatment of sanguinarine with a phosphatidylinositol 3'-kinase (PI3K) inhibitor and an ERK inhibitor but not JNK and p38 inhibitors. Overall, our data indicate that the proapoptotic effects of sanguinarine in HepG2 cells depend on ROS production and the activation of both intrinsic and extrinsic signaling pathways, which is mediated by blocking PI3K/Akt and activating the ERK pathway. Thus, our data suggest that sanguinarine may be a natural compound with potential for use as an antitumor agent in liver cancer.

Analysis on the Movement of Bag-Net in Set-Net by Telemetry Techniques (텔레메트리 기법에 의한 정치망 원통의 거동 해석)

  • 황보규;신현옥;양용림;이주희
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.37 no.1
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    • pp.24-34
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    • 2001
  • The authors reconstruct a mooring type underwater positioning system to measure the movement of bag-net in a set-net by long base line mode with four transponders attached on the bag-net in latitudinal and a transponder fixed on the sea bed. To confirm the practical use of the system, the field experiments were carried out at the Jaran Bay, Kosung, Kyungnam Prov., on October 6, 2000 (neap tide) and November 28, 2000 (spring tide). And the vertical oscillation of bag-net was observed with three data loggers attached on the bottom of bag-net in longitudinal on November 28, 2000. The longitudinal movement range, the latitudinal one and the vertical one of the bag-net were 3.2 m, 3.4 m and 2.1 m. respectively. At the spring tide, these variations were 7.8 m, 7.8 m and 5.0 m, respectively. The vertical oscillation range about the bottom of the bag-net at near point of the slope net, at the middle part and at far point from the slope net were 3.2 m, 3.7 m and 8.4 m, respectively. The depth of the bottom net was decreased and its vertical oscillation appeared frequently when the current speed was more than 10 cm/s and the current direction was significantly different from the longitudinal axis of the bag-net. The variation of hydrophone coordinates measured by the transponder fixed on the sea bed presents that hydrophones equipped to the frame line of the set-net could be moved within several meters due to the tidal current. The fact indicates that the compensation of hydrophone coordinates is necessary to reduce the measuring errors. The position measuring errors of x, y and z axis of the system measured in the cage of aquaculture were 0.6 m, 0.8 m, and 1.2 m, respectively. And the errors of the transponders those were close to the base lines or placed in the baselines were smaller than those of others.

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기운(氣韻)의 현대적(現代的) 해석(解析)에 관한 연구(硏究) -기운(氣韻)의 시각화(視覺化)를 중심(中心)으로-

  • Lee, Seong-Yeong
    • Journal of Science of Art and Design
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    • v.10
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    • pp.111-159
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    • 2006
  • The study is to examine the concept, origin, developmental process, and characteristics of 'Kioonsangdong,' or 'lively energy' to look into whether 'Kioon' maybe interpreted by modern sense and sensitivity and be applied to contemporary creative activities, and to explore whether the ideality of 'Kioon' may be transferred into visualization in pictures. The article defines the scope of 'Ki' as 'Ki(energy)' of artistry and sees the Wei, Chin and the South & North dynasties as its derived point. In Chapter I, before the examination of 'Kioon,' 'the relationship of Ki and Oon,' and 'interrelationship of Kioon (energy) and Sangdong (liveliness) are investigated. It is impossible to define Kioon in a word due to its being abstract. Thus, although it does not seem to be unlimited, focusing on putting a variety of concepts of Kioonsangdong in order, it classifies the subject, from which such Kioon reveals itself, into 'its former self,' things of the object,' 'character,' and 'brush and Chinese ink.' Then, with selected representative works for each category, it examines how Kioonsangdong is reflected in the works. In addition, it comprehensively argues on Kioon through presenting the points of Kioon theories by many an art critic and artist from the Wei, Chin and the South & North dynasties to modem China. In Chapter II, the study analyzes the Kioon-reflected works that have been examined in Chapter 1 in the light of the Kioon theories of 'blanks,' 'styles of brushmanship,' and 'techniques of Chinese ink,' and by selecting and analyzing representative artists and works in each era, it investigates how Kioon had been transformed as times had changed. In Chapter III, which is the core of the study, is on contemporary interpretations of Kioon. I intend to interpret Kioon as scent. In other words, through replacing abstract Kioon with the olfactory sense, actually realizing and forming it, and then visualizing it onto my own work, I attempt to grope for contemporary interpretations of Kioon. That is to say, I explain how Kioon is transformed into scent on the grounds that the origins of Kioon may be detected in literature and aesthetics. Besides, the study looks into the process that 'the scent of the olfactory sense' turns into 'the scent of art,' which I assert by contemporary interpretations, and shows in details that it may be visualized in pictures presenting quotes. In Chapter IV, it analyzes Kioonsangdong expressed visually as the scent of art in my own work in terms of the three techniques of blanks, brushmanship, and Chinese ink.

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