• Title/Summary/Keyword: Science and Technology (S&T)

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Magnetic relaxation measurement of infinite layer superconductor Sr$_{0.9}$La$_{0.1}$CuO$_2$

  • Kim, Heon-Jung;Kim, Mun-Seog;Cung, C.U.;Kim, Ji-Yeon;Lee, Sung-Ik
    • 한국초전도학회:학술대회논문집
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    • v.10
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    • pp.121-124
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    • 2000
  • The time dependence of irreversible magnetization of grain aligned infinite layer superconductor Sr$_{0.9}$La$_{0.1}$CuO$_2$ was measured in temperature range of 2 K < T < 30 K for H= 0.5 T, 1.0 T and 1.5 T parallel to c-axis. From this, we calculated normalized flux creep rate S(T) ${\equiv}$ dlnM/dlnt and found that the temperature independent region in S(T) is significantly wide in comparision with other cuprate superconductors. Using the method of Maley et al., we also deduce the current density dependence of pinning potential and glassy exponent ${\mu}$.

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Coherent X-ray Diffraction Imaging with Single-pulse Table-top Soft X-ray Laser

  • Kang, Hyon-Chol;Kim, H.T.;Lee, S.K.;Kim, C.M.;Choi, I.W.;Yu, T.J.;Sung, J.H.;Hafz, N.;Jeong, T.M.;Kang, S.W.;Jin, Y.Y.;Noh, Y.C.;Ko, D.K.;Kim, S.S.;Marathe, S.;Kim, S.N.;Kim, C.;Noh, D.Y.;Lee, J.
    • Proceedings of the Optical Society of Korea Conference
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    • 2008.02a
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    • pp.429-430
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    • 2008
  • We demonstrate coherent x-ray diffraction imaging using table-top x-ray laser at a wavelength of 13.9nm driven by 10-Hz ti:Sapphire laser system at the Advanced Photonics Research Institute in Korea. Since the flux of x-ray photons reaches as high as $10^9$ photons/pulse in a $20{\times}20{\mu}m^2$ field of view, we measured a ingle-pulse diffraction pattern of a micrometer-scale object with high dynamic range of diffraction intensities and successfully reconstructed to the image using phase retrieval algorithm with an oversampling ratio of 1:6. the imaging resolution is $^{\sim}150$ nm, while that is much improved by stacking the many diffraction patterns. This demonstration can be extended to the biological sample with the diffraction limited resolution.

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Theoretical Review on the Welfare Policy of Science & Technology Personnel (과학기술인 복지 정책에 관한 이론적 고찰 - Soft Infra 구축을 중심으로 -)

  • Lee Jong Min;Park Jeong Su;Hwang Du Hui;Jeong Seon Yang
    • Proceedings of the Technology Innovation Conference
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    • 2005.06a
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    • pp.140-158
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    • 2005
  • Science & Technology (S&T) is the most important thing to attain competitiveness in the 21st century. Our traditional S&T policies have been focused on hardware infra structure. But, we should consider soft infra of S&T to enhance welfare development of S&T personnel. S&T should be had a correct understanding method of the creation for S&T culture. It implies that S&T policy in the 21st century should consider non-material factors which include social, human, environment and culture. Under this background. This paper defines the concept of welfare of S&T personnel. Also this paper deals with the change of S&T policy of Korea and analyzes the characteristic of each phase. This paper argues that all actors (for example S&T personnel, corporate using S&T, public) should participate in the process of S&T innovation since the 21st century is the generation of popularization of S&T. The purpose of this paper is to suggest a few methods of welfare improvement of S&T personnel to reinforce soft infra structure of S&T.

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Design and Implementation of Digital Contents Service System using Re-Direction Technique (Re-Direction 기법을 활용한 전자원문 연계시스템 설계 및 구현)

  • Cho, Sung-Nam;Lee, Sang-Hwan;Lee, Sang-Gi;Hwang, Chong-Sun;Chung, Taik-Yeong
    • Proceedings of the Korea Information Processing Society Conference
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    • 2004.05a
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    • pp.1389-1392
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    • 2004
  • 정보통신 및 인터넷의 급속한 발전으로 전자원문 서비스 등 웹 서비스가 활발하게 이루어지고 있으나, 기존 웹 서비스에 대한 연구는 웹 서비스를 차별화하기 위해 HTTP의 속도지연 문제해결이나 서비스 차별화 방안에 대해 이루어지고 있다. 그러나, 타 시스템의 웹 서비스와 연계시 해당 웹 문서에 대한 제어권 확보에 관한 연구는 미미하다. 따라서, 본 논문에서는 타 시스템의 웹 문서에 대해 제어권 확보를 위해 Re-Direction Agent를 활용하여 해외전자원문 연계시스템을 구현하고자 한다.

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20(S)-Ginsenoside Rh2 displays efficacy against T-cell acute lymphoblastic leukemia through the PI3K/Akt/mTOR signal pathway

  • Xia, Ting;Zhang, Jin;Zhou, Chuanxin;Li, Yu;Duan, Wenhui;Zhang, Bo;Wang, Min;Fang, Jianpei
    • Journal of Ginseng Research
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    • v.44 no.5
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    • pp.725-737
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    • 2020
  • Background: T-cell acute lymphoblastic leukemia (T-ALL) is a kind of aggressive hematological cancer, and the PI3K/Akt/mTOR signaling pathway is activated in most patients with T-ALL and responsible for poor prognosis. 20(S)-Ginsenoside Rh2 (20(S)-GRh2) is a major active compound extracted from ginseng, which exhibits anti-cancer effects. However, the underlying anticancer mechanisms of 20(S)-GRh2 targeting the PI3K/Akt/mTOR pathway in T-ALL have not been explored. Methods: Cell growth and cell cycle were determined to investigate the effect of 20(S)-GRh2 on ALL cells. PI3K/Akt/mTOR pathway-related proteins were detected in 20(S)-GRh2-treated Jurkat cells by immunoblotting. Antitumor effect of 20(S)-GRh2 against T-ALL was investigated in xenograft mice. The mechanisms of 20(S)-GRh2 against T-ALL were examined by cell proliferation, apoptosis, and autophagy. Results: In the present study, the results showed that 20(S)-GRh2 decreased cell growth and arrested cell cycle at the G1 phase in ALL cells. 20(S)-GRh2 induced apoptosis through enhancing reactive oxygen species generation and upregulating apoptosis-related proteins. 20(S)-GRh2 significantly elevated the levels of pEGFP-LC3 and autophagy-related proteins in Jurkat cells. Furthermore, the PI3K/Akt/mTOR signaling pathway was effectively blocked by 20(S)-GRh2. 20(S)-GRh2 suppressed cell proliferation and promoted apoptosis and autophagy by suppressing the PI3K/Akt/mTOR pathway in Jurkat cells. Finally, 20(S)-GRh2 alleviated symptoms of leukemia and reduced the number of white blood cells and CD3 staining in the spleen of xenograft mice, indicating antitumor effects against T-ALL in vivo. Conclusion: These findings indicate that 20(S)-GRh2 exhibits beneficial effects against T-ALL through the PI3K/Akt/mTOR pathway and could be a natural product of novel target for T-ALL therapy.

Building and Analysis of Semantic Network on S&T Multilingual Terminology (과학기술 전문용어의 다국어 의미망 생성과 분석)

  • Jeong, Do-Heon;Choi, Hee-Yoon
    • Journal of Information Management
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    • v.37 no.4
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    • pp.25-47
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    • 2006
  • A terminology system capable of providing interpretations and classification information on a multilingual science and technology(S&T) terminology is essential to establish an integrated search environment for multilingual S&T information systems. This paper aims to build a base system to manage an integrated information system for multilingual S&T terminology search. It introduces a method to build a search system for S&T terminologies internally linked through the multilingual semantic network and a search technique on the multiple linked nodes. In order to provide a foundation for further analysis researches, it also attempts to suggest a basic approach to interpret terminology clusters generated with those two search methods.

Preoperative Radiological Parameters to Predict Clinical and Radiological Outcomes after Laminoplasty

  • Lee, Su Hun;Son, Dong Wuk;Shin, Jun Jae;Ha, Yoon;Song, Geun Sung;Lee, Jun Seok;Lee, Sang Weon
    • Journal of Korean Neurosurgical Society
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    • v.64 no.5
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    • pp.677-692
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    • 2021
  • Many studies have focused on pre-operative sagittal alignment parameters which could predict poor clinical or radiological outcomes after laminoplasty. However, the influx of too many new factors causes confusion. This study reviewed sagittal alignment parameters, predictive of clinical or radiological outcomes, in the literature. Preoperative kyphotic alignment was initially proposed as a predictor of clinical outcomes. The clinical significance of the K-line and K-line variants also has been studied. Sagittal vertical axis, T1 slope (T1s), T1s-cervical lordosis (CL), anterolisthesis, local kyphosis, the longitudinal distance index, and range of motion were proposed to have relationships with clinical outcomes. The relationship between loss of cervical lordosis (LCL) and T1s has been widely studied, but controversy remains. Extension function, the ratio of CL to T1s (CL/T1s), and Sharma classification were recently proposed as LCL predictors. In predicting postoperative kyphosis, T1s cannot predict postoperative kyphosis, but a low CL/T1s ratio was associated with postoperative kyphosis.

Identification of Lactobacillus spp. associated with nematodes in peach farm soil (복숭아 농장 토양에서 Nematodes와 연관된 Lactobacillus spp.의 분리 및 동정)

  • Lee, Woo-Hyun;Choi, Jae Im;Lee, Jin Il;Lee, Won-Pyo;Yoon, Sung-Sik
    • Korean Journal of Microbiology
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    • v.53 no.3
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    • pp.163-169
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    • 2017
  • Strains D4 and D5 were isolated from peach-rotten soil during the peach harvest season. The isolates were identified based on morphological and biochemical characterization, and identification was determined by 16S rRNA gene sequencing. Results showed that D4 has high similarity to Lactobacillus plantarum ATCC $14917^T$ and Lactobacillus pentosus ATCC $8041^T$ at 99.05% and 98.98%, respectively. D5 was also similar to Lactobacillus pentosus ATCC $8041^T$ and Lactobacillus plantarum ATCC $14917^T$ at 98.71% and 98.64%, respectively. In contrast, isolates showed differences in carbohydrate utilization in comparison to Lactobacillus plantarum ATCC $14917^T$ and Lactobacillus pentosus ATCC $8041^T$. In view of this we performed VITEK MS matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) analysis, multiplex PCR fingerprinting, and random amplified polymorphic DNA (RAPD)-PCR to further confirm the identification of D4 and D5. The results of these analyses showed that both strains were most similar to Lactobacillus plantarum.

An Analysis of Statistical Indicators on the Infrastructure of Science and Technology Culture in Korea (과학기술문화 하부구조에 관한 통계지표 분석)

  • Song, Sung-Soo
    • Journal of Science and Technology Studies
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    • v.6 no.2 s.12
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    • pp.185-205
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    • 2006
  • This article analyzes statistical indicators on the infrastructure of S&T culture in Korea. In the case of visible infrastructure, science museums, S&T programs in TV, and S&T books are not sufficiently secured except for internet. The utilization of visible infrastructure tends to be increased but in rudimentary stage. In relation to invisible infrastructure, public interest and understanding of &T is underdeveloped, social status of S&T personnel is low compared to social importance, and participation in S&T policy of S&T personnel and citizens organization is limited. For the development of statistical indicators in S&T culture, personal, institutional, and social contexts should be much considered, surveys on the particular social groups are systematically pursued, and a white paper on the S&T culture in Korea needs to be published.

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