• Title/Summary/Keyword: REF

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Hydraulic Experiments of Stem Waves along a Vertical Wall due to Unidirectional Random Waves (직립벽을 따른 일방향 불규칙파의 연파실험)

  • Lee, Jong-In;Choi, Jun-Woo;Yoon, Sung-Bum
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.20 no.1
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    • pp.49-61
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    • 2008
  • This study investigates the characteristics of stem waves along a vertical wall generated by obliquely incident random waves through laboratory experiments conducted in a wave basin and numerical simulations using REF/DIF S model developed by Kirby and $\ddot{O}zkan$(1994). The investigation is focused on the effect of random waves on the propagation characteristics of stem waves and the difference or similarity between monochromatic and random waves. The results of REF/DIF S model are compared with laboratory measurements and good agreements are obtained. The relative significant wave height along a wall is almost same with monochromatic condition, but the wave pattern along normal to the wall shows a significant difference.

Ref-1 protects against FeCl3-induced thrombosis and tissue factor expression via the GSK3β-NF-κB pathway

  • Lee, Ikjun;Nagar, Harsha;Kim, Seonhee;Choi, Su-jeong;Piao, Shuyu;Ahn, Moonsang;Jeon, Byeong Hwa;Oh, Sang-Ha;Kang, Shin Kwang;Kim, Cuk-Seong
    • The Korean Journal of Physiology and Pharmacology
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    • v.25 no.1
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    • pp.59-68
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    • 2021
  • Arterial thrombosis and its associated diseases are considered to constitute a major healthcare problem. Arterial thrombosis, defined as blood clot formation in an artery that interrupts blood circulation, is associated with many cardiovascular diseases. Oxidative stress is one of many important factors that aggravates the pathophysiological process of arterial thrombosis. Apurinic/apyrimidinic endonuclease 1/redox factor-1 (Ref-1) has a multifunctional role in cells that includes the regulation of oxidative stress and anti-inflammatory function. The aim of this study was to investigate the therapeutic effect of adenovirus-mediated Ref-1 overexpression on arterial thrombosis induced by 60% FeCl3 solution in rats. Blood flow was measured to detect the time to occlusion, thrombus formation was detected by hematoxylin and eosin staining, reactive oxygen species (ROS) levels were detected by high-performance liquid chromatography, and the expression of tissue factor and other proteins was detected by Western blot. FeCl3 aggravated thrombus formation in carotid arteries and reduced the time to artery occlusion. Ref-1 significantly delayed arterial obstruction via the inhibition of thrombus formation, especially by downregulating tissue factor expression through the Akt-GSK3β-NF-κB signaling pathway. Ref1 also reduced the expression of vascular inflammation markers ICAM-1 and VCAM-1, and reduced the level of ROS that contributed to thrombus formation. The results showed that adenovirus-mediated Ref-1 overexpression reduced thrombus formation in the rat carotid artery. In summary, Ref-1 overexpression had anti-thrombotic effects in a carotid artery thrombosis model and could be a target for the treatment of arterial thrombosis.

A Study on the Citation Analysis of korea science journal based on Digital Object Identifier (이학분야 국내학술논문의 DOI기반 인용분석 연구)

  • Jung, Eun-Kyoung;Kwak, Seung-Jin
    • Proceedings of the Korean Society for Information Management Conference
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    • 2012.08a
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    • pp.115-119
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    • 2012
  • 본 연구의 목적은 이학분야 국내학술지 중 DOI를 기반으로 하여 인용정보를 제공하고 있는 학술지를 대상으로 피인용정보를 분석하고 WoS, Scopus와 비교를 통해 유사점과 차이점을 찾는 것이다. DOI를 등록하고 있고 WoS, Scopus에 공통으로 등재되어있는 5종의 이학분야 학술지의 CrossRef 피인용정보를 분석한 결과 논문수가 많은 2개 학술지의 인용률이 높았으며 모두 낮은 자기인용률을 보이고 있다. 전체적으로 CrossRef의 고유논문은 논문수와 인용수가 가장 큰 학술지 1종만이 11%이고 나머지 4종의 학술지는 5% 미만으로 대부분 WoS, Scopus 논문에 포함되었다. DB별 비교를 위해 3년간(2008~2010) 발행된 논문의 피인용도를 확인한 결과 모든 학술지에서 WoS의 인용률이 가장 높았고 CrossRef의 경우 레코드 수는 많지만, 전문색인DB가 아니고 참고문헌 등록이 모두 이뤄지지 않아 인용률이 가장 낮았다. 하지만 CrossRef 고유논문비율이 11%인 학술지의 경우 Scopus 보다 인용률이 높은 것으로 나타났다.

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Cytoprotective effect of rhamnetin on miconazole-induced H9c2 cell damage

  • Lee, Kang Pa;Kim, Jai-Eun;Park, Won-Hwan
    • Nutrition Research and Practice
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    • v.9 no.6
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    • pp.586-591
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    • 2015
  • BACKGROUND/OBJECTIVES: Reactive oxygen species (ROS) formation is closely related to miconazole-induced heart dysfunction. Although rhamnetin has antioxidant effects, it remained unknown whether it can protect against miconazole-induced cardiomyocyte apoptosis. Thus, we investigated the effects of rhamnetin on miconazole-stimulated H9c2 cell apoptosis. MATERIALS/METHODS: Cell morphology was observed by inverted microscope and cell viability was determined using a WelCount$^{TM}$ cell proliferation assay kit. Miconazole-induced ROS production was evaluated by fluorescence-activated cell sorting with 6-carboxy-2',7'-dichlorofluoroscein diacetate ($H_2DCF$-DA) stain. Immunoblot analysis was used to determine apurinic/apyrimidinic endonuclease 1 (APE/Ref-1) and cleaved cysteine-aspartic protease (caspase) 3 expression. NADPH oxidase levels were measured using real-time polymerase chain reaction. RESULTS: Miconazole (3 and $10{\mu}M$) induced abnormal morphological changes and cell death in H9c2 cells. Rhamnetin enhanced the viability of miconazole ($3{\mu}M$)-treated cells in a dose-dependent manner. Rhamnetin (1 and $3{\mu}M$) treatment downregulated cleaved caspase 3 and upregulated APE/Ref-1 expression in miconazole-stimulated cells. Additionally, rhamnetin significantly reduced ROS generation. CONCLUSIONS: Our data suggest that rhamnetin may have cytoprotective effects in miconazole-stimulated H9c2 cardiomyocytes via ROS inhibition. This effect most likely occurs through the upregulation of APE/Ref-1 and attenuation of hydrogen peroxide levels.

Patterns of Citing Korean DOI Journals According to CrossRef's Cited-by Linking and a Local Journal Citation Database

  • Seo, Tae-Sul;Jung, Eun-Gyeong;Kim, Hwanmin
    • Journal of Information Science Theory and Practice
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    • v.1 no.2
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    • pp.58-68
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    • 2013
  • Citing literature is a very important activity for scholars in writing articles. Many publishers and libraries build citation databases and provide citation reports on scholarly journals. Cited-by linking is a service representing what an article cites and how many times it cites a specific article within a journal database. Recently, information services based on DOIs (Digital Object Identifiers) have been increasing in number. CrossRef, a non-profit organization for the DOI registration agency, maintains the DOI system and provides the cited-by linking service. Recently, the number of Korean journals adopting DOI is also rapidly increasing. The Korea Institute of Science and Technology Information (KISTI) supports Korean learned societies in DOI related activities in collaboration with CrossRef. This study analyzes cited patterns of Korean DOI journal articles using CrossRef's cited-by linking data and a Korean journal citation database. This analysis has been performed in terms of publication country and the language of journals citing Korean journal articles. The results show that DOI, SCI(E) (Science Citation Index (Expanded)), and English journals are more likely to be cited internationally.

Properties of Shrinkage Reducing Agent and Mortar with C12A7-based Slag and Petroleum Cokes Ash (C12A7계 슬래그와 석유 코크스 연소재를 사용한 수축저감재 및 모르타르의 특성)

  • Chu, Yong Sik;Park, Soo Hyun;Seo, Sung Kwan;Park, Jae Wan
    • Journal of the Korean Ceramic Society
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    • v.50 no.5
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    • pp.319-325
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    • 2013
  • In this study, petroleum cokes ash and $C_{12}A_7$-based slag were used for the shrinkage reduction and strength enhancement of mortar. The hydration properties of shrinkage reduction agents were analysed. The flow, change of length and compressive strength were experimented with mortar-added shrinkage reduction agents. As a result of this study, petroleum cokes ash : $C_{12}A_7$-based slag = 60~80% : 20~40% showed excellent results. In the case of mortar with 20% $C_{12}A_7$-based slag, the setting time and change of length were similar to Ref. mortar. The flow and compressive strength were superior to Ref. mortar. In the case of mortar with a 40% $C_{12}A_7$-based slag, the setting time was longer than Ref. mortar. The compressive strength of 3 days and 7 days were superior to Ref. mortar.

Application System Plan for Scholarly Information Producer using the result of Cited-by linking based on CrossRef DOI (CrossRef DOI 기반 Cited-by linking 결과의 학술정보생산자 활용시스템 연구)

  • Jung, Eun-Kyoung;Kim, Byung-Kyu;Jeon, Ji-Young;Choi, Seon-Heui;Kang, Mu-Yeong
    • Proceedings of the Korea Information Processing Society Conference
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    • 2011.04a
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    • pp.1573-1575
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    • 2011
  • KISTI는 CrossRef/DOI 기탁사업을 통해 학술정보생산자인 학회나 기관에게 해외유통망을 지원하는 사업을 해오고 있다. 그리고 DOI 기반의 학술논문간 인용정보 서비스인 Cited-by linking 결과를 과학 기술학회마을을 통해 논문의 인용횟수와 인용논문정보를 제공하고 있다. CrossRef에서 회원에게만 제공하는 Cited-by linking 결과를 분석해보면, KISTI에서 기탁하는 논문수가 증가함에 따라 인용논문수도 지속적으로 증가하고 있는 것을 볼 수 있다[1]. 이에 따라 Cited-by linking 결과를 학회나 기관이 쉽게 접근 할 수 있도록 KISTI 학술정보통합관리시스템에 적용하는 방안을 모색하고자 한다. 학회나 기관이 Cited-by linking결과에 쉽게 접근하여 각 학술지의 인용현황을 관리하고 그 결과 데이터를 활용하여 기존에 서비스되고 있는 정보 외에 필요한 정보를 획득할 수 있도록 지원하는 시스템이다.

A Small Swing Domino Logic for Low Power Consumption (저전력 소비를 위한 저전압 스윙 도미노 로직)

  • 양성현;김두환;조경록
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.41 no.6
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    • pp.17-25
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    • 2004
  • In this paper, we propose a new small swing domino logic for low-power consumption. To reduce the power consumption, both the precharge node and the output node swing the range from 0 to $V_{REF}$- $V_{THN}$, where $V_{REF}$=VDD-n $V_{THN}$ (n=1, 2, and 3). This can be done by adding the inverter structure on domino logic that allows a full swing or a small swing on its input terminal without leakage current. Compared to previous works, the proposed structure can save the power consumption of more than 30% for n=0, 1, 2, and 3 in the equation of $V_{REF}$=VDD-n $V_{THN}$. A multiplier applying the proposed domino logic has been designed and fabricated using a 0.35-${\mu}{\textrm}{m}$ n-well CMOS process under 3.3-V supply voltage. Compared with other previous works, it shows a 30% power reduction and a better feature in power-delay product.lay product.

Influence of Muscle Architecture on Force Enhancement Following Muscle Lengthening (근육 구조특성과 선행 신장성 수축에 의한 항정상태 등척성 근력 증대와의 연관성에 대한 연구)

  • Lee, Hae-Dong;Lee, Jung-Hyun
    • Korean Journal of Applied Biomechanics
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    • v.17 no.3
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    • pp.61-68
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    • 2007
  • When an active muscle is stretched, its steady-state isometric force following stretch is greater than that of a purely isometric contraction as the corresponding muscle length, referred to as force enhancement (FE). The purpose of this study was to investigate possible effects of muscle architecture on the FE. While subject performed maximal isometric dorsiflexion (REF) and isometric-stretch-isometric dorsiflexion (ECC) contractions, ankle joint angle and dorsiflexion torque using a dynamometer and electromyography of the tibialis anterior and the medical gastrocnemius muscles were measure. Simultaneously, real-time ultrasound images of the tibialis anterior were acquired. Regardless of the speed of stretch of the ECC contractions. the torques produced during the isometric phase following stretch ($37.3{\pm}1.5\;Nm$ ($10{\pm}3%$ FE) and $38.3{\pm}1.5$ ($12{\pm}3%$ FE) for the ECC contractions with $15^{\circ}$/s and $45^{\circ}$/s stretch speeds, respectively) were greater than those of the REF contractions ($34.5{\pm}2.5\;Nm$). Moreover, the amount of FE was found to be stretch speed dependent. Angles of pennation ($\alpha$) during the isometric phase following stretch were the same for the REF ($15{\pm}1^{\circ}$) and the ECC ($14{\pm}1^{\circ}$(LS), $15{\pm}1^{\circ}$(LF)). During the same phase, muscle thicknesses were the same ($14.9{\pm}0.6$, and $14.9{\pm}0.5\;mm$ for the REF and the ECC contractions, respectively). For a large limb muscle, the tibialis anterior muscle, a similar amount of force enhancement was observed as did for other human skeletal muscles. Architectural variables, pennation angle and thickness, were not systematically different between the REF and ECC contractions when FE occurred. Therefore, the results of this study suggest that muscle architecture may have little influence on the production of FE.

INEQUALITIES FOR JACOBI POLYNOMIALS

  • Pyung, In Soo;Kim, Hae Gyu
    • Korean Journal of Mathematics
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    • v.12 no.1
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    • pp.67-75
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    • 2004
  • Paul Turan observed that the Legendre polynomials satisfy the inequality $P_n(x)^2-P_{n-1}(x)P_{n+1}(x)$ > 0, $-1{\leq}x{\leq}1$. And G. Gasper(ref. [6], ref. [7]) proved such an inequality for Jacobi polynomials and J. Bustoz and N. Savage (ref. [2]) proved $P^{\alpha}_n(x)P^{\beta}_{n+1}(x)-P^{\alpha}_{n+1}(x)P{\beta}_n(x)$ > 0, $\frac{1}{2}{\leq}{\alpha}$ < ${\beta}{\leq}{\alpha}+2.0$ < $x$ < 1, for the ultraspherical polynomials (respectively, Laguerre ploynomials). The Bustoz-Savage inequalities hold for Laguerre and ultraspherical polynomials which are symmetric. In this paper, we prove some similar inequalities for non-symmetric Jacobi polynomials.

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