자동차산업의 동향 및 전망

이성익,Lee, Seong-Ik 대한타이어공업협회 1997 타이어 Vol.188 No.-

전기 · 자기 재료 : 고온 초전도체의 특성

이성익 ( Sung Ik Lee ),( Jin Woo Chung ) 대한금속재료학회 ( 구 대한금속학회 ) 1988 재료.물성 심포지엄 Vol.- No.-

담배 니코틴에 의한 사람 태아 성상세포에서 종양괴사인자(TNF-α)의 발현 억제작용

손일홍,이성익,양현덕,한선정,석승한,이재규,김재현,박주영,문형인,이성수,Son, Il-Hong,Lee, Sung-Ik,Yang, Hyun-Duk,Han, Sun-Jung,Suk, Seung-Han,Lee, Jai-Kyoo,Kim, Jae-Hyun,Park, Joo-Young,Moon, Hyung-In,Lee, Sung-Soo 대한화학회 2007 대한화학회지 Vol.51 No.3

니코틴은 사람 대식세포에서 interleukin 2 (IL-2)와 종양괴사인자 (tumor necrosis factor-alpha; TNF-α) 가 생성되는 것을 억제하는데, 이러한 억제작용은 cytokine 유전자 발현 중 전사단계에서 전사인자의 활성을 억제함으로써 일어난다. 이러한 니코틴의 면역반응 억제작용은 아프타성궤양 및 궤양성대장염, 알레르기성폐 포염, 건초열 등에서도 보고되고 있다. 만일 중추신경계에서도 위와 같은 니코틴의 면역억제 작용이 일어난 다면 다발성경화증과 같은 면역반응 매개질환의 치료에 새로운 전기가 마련될 수 있을 것이다. 본 연구에서 는 중추신경계의 여러 면역반응 매개질환의 병태생리에 대한 이해를 넓히고자, 이미 알려진 니코틴의 cytokine 생성억제가 사람 중추신경계의 성상세포에서도 일어남을 확인하고 그 억제기전을 밝히고자 하였다. 이를 위 하여 사람 태아 성상세포에 다양한 농도의 니코틴과 IL-1β를 처리한 다음 TNF-α mRNA의 발현 정도와 NF- κB의 활성을 비교, 분석하여 다음과 같은 결과를 얻었다. 1. 사람 태아 성상세포를 0.1-20 μg/ml의 니코틴으로 처리해 본 결과 10 μg/ml 이상의 농도에서 세포독성능이 나타나기 시작하였다. 2. 사람 태아 성상세포에 IL- 1β를 처리하면 2시간만에 TNF-α mRNA가 최대로 발현되었으며 그 이후로는 점진적으로 감소하였다. 3. 사 람 태아 성상세포를 1 및 0.1 μg/ml의 니코틴으로 전처리한 후 IL-1β로 자극한 군에서는 IL-1β 단독 처리군에 비해 TNF-α mRNA의 발현이 감소하는 양상을 보였다. 1 μg/ml의 니코틴을 처리한 경우에는 8시간 이후부터 TNF-α mRNA의 발현이 현저하게 감소하여 12시간에 최대로 감소하였다. 또한 0.1 μg/ml의 니코틴을 처리한 군에서는 24시간에 가장 현저하게 감소하였다. 4. 성상세포에 IL-1β로 처리한 군에서는 강력한 NF-κB의 활성 을 확인할 수 있었으며, 니코틴을 전처리하고 IL-1β 자극한 군에서는 NF-B의 활성이 감소하였다. 결론적으로 일정농도 이상의 니코틴은 세포독성효과를 나타내나 적정한 농도와 시간 경과후 니코틴은 사람 태아 성상세포에서 IL-1β에 의해 유도되는 TNF-α의 발현 감소를 유도하며, 이는 NF-κB의 활성을 감소시킴으로써 나타난다고 생각된다. The Tumor necrosis factor-α, (TNF-α), is involved in the pathogenesis of multiple sclerosis and contributes to the degeneration of oligodendrocytes as well as neurons. Nicotine has been found to have immunosuppressive and inflammation-suppressing effects. Astrocytes, the major glial cells in the CNS, are capable of producing TNF-α at both the mRNA and protein levels in response to interleukin-1 (IL-1) or TNF-α. Nicotine has been shown to influence glial cell functions. To order to explore the role of astrocytes in the production of TNF-α, astrocytes were pretreated with nicotine and are stimulated with IL-1β to determine their effects on TNF-α production. The results are as follows. Cytotoxic effects of nicotine on human fetal astrocytes were noted above 10 μg/ml of nicotine. The effect of IL-1β on TNF-α mRNA expression in primary cultured human fetal astrocytes was maximal at 2 h after IL- 1β(100 pg/ml) treatment. Human fetal astrocytes were pretreated with 0.1, 1, and 10 μg/ml of nicotine and then stimulated with IL-1β (100 pg/ml) for 2 h. The inhibitory effect of nicotine on expressions of TNF-α mRNA in human fetal astrocytes with pretreated 0.1 μg/ml of nicotine is first noted at 8 hr, and the inhibitory effect is maximal at 12 h. The inhibitory effect at 1 μg/ml of nicotine is inhibited maximal at 24 h. Nicotine at 0.1, 1 and 10 μg/ml concentrations significantly inhibits IL-1β-induced NF-κB activation. Collectively, this study indicates that nicotine might inhibit the expression of TNF-α in activated human fetal astrocytes.

불면증 환자에 대한 침치료 전후 정량화 뇌파 분석: Z Scored Absolute Power and sLORETA

이고은 ( Go Eun Lee ),문수정 ( Su Jeong Mun ),이성익 ( Sung Ik Lee ),임정화 ( Jung Hwa Lim ),위영만 ( Young Man We ),문광수 ( Kwang Su Moon ),유영수 ( Yeoung Su Lyu ),강형원 ( Hyung Won Kang ) 대한한방신경정신과학회 2016 동의신경정신과학회지 Vol.27 No.3

Objectives: To investigate the neurophysiological effect of acupuncture treatment on insomnia patients using quantitative electroencephalography (QEEG) and standardized Low Resolution Brain Electromagnetic Tomography method (sLORETA). Background: Insomnia is one of the commonly encountered symptoms in primary medical care. Recent studies of acupuncture for insomnia reported that the acupuncture groups showed significant improvements compared with the control groups. However, the neurophysiological mechanism of acupuncture in the treatment of insomnia has not been revealed and a few studies have measured the effect of acupuncture treatment using QEEG. Methods: Participants who had some problems in initiating or maintaining sleep, or had non-restorative sleep for more than 3 days a week and ISI scores above 8 and below 21 were treated by acupuncture for 2 weeks (3 times a week, total 6 times). We assessed the effectiveness of acupuncture for insomnia by the PSQI (Pittsburgh Sleep Quality Index) at baseline and at 2 weeks after the end of treatment (4th week). Also, we performed EEG and analysed the EEG data at baseline and at the end of treatment (2nd week) on the linked ears montage using the Neuroguide software program and sLORETA. Results: Thirty-two participants were enrolled and 2 participants dropped out because of personal reasons. Among the 30 participants, EEGs of 12 participants were included in the analysis of QEEG and sLORETA. Total score on the ISI and PSQI was significantly decreased after acupuncture treatment. The number of electrodes exceeding the range of 90% (±1.65) or 95% (±1.96) in the z scored absolute power of beta was significantly decreased after acupuncture treatment. There was no significant change in brain activation between pre- and post-acupuncture using sLORETA. Conclusions: The deviation of absolute power compared to the normative database was significantly decreased after acupuncture treatment in the alpha and beta ranges. Therefore, we suggest that acupuncture treatment for insomnia might be effective through the central nervous system especially in the brain. There are many limitations to drawing any conclusion. Further studies are needed in the future to overcome these limitations.

Vortex Avalanche in Gold-Coated and Finite-Sized MgB2 Thin Films

최은미,이성익,{AA}. A. F. Olsen,D. V. Shantsev,Hyun-Sook Lee,T. H. Johansen 한국물리학회 2006 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.48 No.5I

The vortex avalanches in carbon-free MgB2 thin films were studied using magneto-optical imaging. The main focus of this study was the effect of a gold coating and the sample size on the occurrence of dendritic flux avalanches. For this purpose, we prepared two different sets of MgB2 films. In the first, the films had gold coatings of various thickness, and in the second set bare MgB2 films were patterned into long strips of different widths. The dendritic flux avalanches essentially disappeared for gold coatings thicker than 2.5 μm. Also, for strip widths less than 0.3 × 3 mm2, the formation of flux dendrites were suppressed. The results are consistent with a thermomagnetic origin of the dendritic instability.

Nature of the Fluctuation Conductivity in La1:87Y0:13CuO4

Hyun-Sook Lee,이성익,Akio Tsukada,Heon-Jung Kim,Hyun-Jung Kim,Michio Naito 한국물리학회 2006 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.48 No.5I

The in-plane resistivity (½) of La1:87Y0:13CuO4 with Tc ¼ 17 K was measured and analyzed as a function of the temperature (T). From the ½(T) measured under various magnetic .elds (H) for H k c, we determined the °uctuation conductivity ¾fl = 1=½(T) ¡ 1=½n(T). The normal-state resistivity ½n(T) in this compound was shown to follow a T2 dependence for 20 K < T < 200 K and a logarithmically corrected T2 dependence for 200 K < T < 300 K. The ¾fl followed the three-dimensional (3D) scaling behavior suggested by Ullah and Dorsey. This is consistent with the previously reported 3D nature of La1:87Y0:13CuO4 obtained from the angle-dependent critical current density and the angle-dependent vortex glass transition temperature [1,2].

Effect of $Y_2O_3$ Nanoparticles on Critical Current Density of $YBa_2Cu_3O_{7-x}$ Thin Films

위창환,강병원,오상준,이성익,Tran, H.D.,Reddy, D.Sreekantha,Wie, C.H.,Kang, B.,Oh, Sang-Jun,Lee, Sung-Ik 한국초전도학회 2009 Progress in superconductivity Vol.11 No.1

Introduction of proper impurity into $YBa_2Cu_3O_{7-x}$ (YBCO) thin films is an effective way to enhance its flux-pinning properties. We investigate effect of $Y_2O_3$ nanoparticles on the critical current density $J_c$ of the YBCO thin films. The $Y_2O_3$ nanoparticles were created perpendicular to the film surface (parallel with the c-axis) either between YBCO and substrate or on top of YBCO, YBCO/$Y_2O_3$/LAO or $Y_2O_3$/YBCO/STO, by pulsed laser deposition. The deposition temperature of the YBCO films were varied ($780^{\circ}C$ and $800^{\circ}C$) to modify surface morphology of the YBCO films. Surface morphology characterization revealed that the lower deposition temperature of $780^{\circ}C$ created nano-sized holes on the YBCO film surface which may behave as intrinsic pinning centers, while the higher deposition temperature produced much denser and smoother surface. $J_c$ values of the YBCO films with $Y_2O_3$ particles were either remained nearly the same or decreased for the samples in which YBCO is grown at $780^{\circ}C$. On the other hand, $J_c$ values were enhanced for the samples in which YBCO is grown at higher temperature of $800^{\circ}C$. The difference in the effect of $Y_2O_3$ can be explained by the fact that the higher deposition temperature of $800^{\circ}C$ reduces intrinsic pinning centers and $J_c$ is enhanced by introduction of artificial pinning centers in the form of $Y_2O_3$ nanoparticles.

재해대응을 고려한 연안토지이용 관리방안에 관한 소고

전영길(Jeon, Yeong Gil),이성익(Lee, Seong Yik) 한국지적정보학회 2011 한국지적정보학회지 Vol.13 No.2

국토공간 중 연안토지이용에 관한 중요성이 크게 부각되고 있다. 이는 최근 일본의 쓰나미와 원전사고로 인해 더욱 큰 관심을 불러 일으킨다. 종래까지 한국에서는 전체적인 연안의 토지이용에 특화된 토지관리정책은 일부 있으나, 특히 재해, 재난을 대비한 연안토지이용방안에 대한 연구는 아직 미진한 실정이다. 본 연구는, 강원도 동해안의 한 지역을 사례로 하여, 다음과 같이 순차적인 연구내용의 절차를 수행한 것이다. 1) 먼저, 지진, 해일시에 파괴 및 침수가 예상되는 피해지역의 범위를 파악하고, 2) 피해지역 내의 지목별 토지이용현황을 분석하며, 3) 이를 토대로, 장래에 지진, 해일과 같은 재난에 대비하기 위한 바람직한 연안토지이용 방안을 모색해 보고자 하였다. 본 논문의 사례연구 결과, 아래와 같은 몇가지 정책적 시사점을 도출할 수 있다. 첫째, 현재 한국의 동해안 일부인 사례지역의 경우, 연안지역 전체가 지진, 해일에 매우 취약한 토지이용현황을 보이고 있다. 둘째, 구체적으로 보면, 지목 중 "내, 잡종지,도로"등의 구성비율이 높아, 지진, 해일 등의 재난이 가정될 때, 그 인적, 물적 피해가 상당하리라 염려된다. 셋째, 앞으로 연안지역의 환경보전 및 오염방지, 그리고 특히 지진, 해일 등과 같은 재난에 대비할 토지 이용구조를 유도하기 위해서는, 국가정책적으로 강력한 규제수단이 강구되어야 할 것이다. 아울러, 연안토지이용구조 통제의 강제적 규제수단의 하나로서, 필자는(가칭) "Blue Belt"의 설정을 제언하고자 한다. The importance of the management of "coastal land use"is more increasing. The recent disaster on earthquake and tsunami in Japan made us more being intrested in it. Till now, there is few specified land use policy on coastal district, and there are few research on "coastal land use" against the disaster like earthquake or tsunami in Korea. The contents of this case study is summarized, sequentially, as belows ; 1) investigation of rigions which are predicted to be damaged by disaster. 2) Analysis of the land use forms in the "damaged area" by land category. 3) Consideration on the policy for the future korean "coastal land use" against the environmental contamination or natural disaster. As a result of this case suty, we can extract some political implications ; ⅰ) Most korean "coastal land use" form is estimated as fragile to any natural disater. ⅱ) Specified by land categories, the ratio of "building site", "miscellaneous" and "road" is very high in "damaged area". So we can presume that broad area near coast area may cause big damages on physical resources and serious injuries on residents. ⅲ) We should invent powerful regulative policy urgently for the future "coastal land use", which protects the environmental contamination or resists against the natural disaster like earthquake or tsunami. As a compulsory regulation, I suggest the establishment of (so called) "Bleu Belt", which manage and control koran "coastal land use" synthetically.

Al 첨가가 $MgB_2$ 단결정의 비등방성에 미치는 영향에 대한 연구

강병원,이현숙,박민석,이성익,Kang, Byeong-Won,Lee, Hyun-Sook,Park, Min-Seok,Lee, Sung-Ik 한국초전도학회 2008 Progress in superconductivity Vol.9 No.2

We have studied superconducting properties of $Mg_{1-x}Al_xB_2$ single crystals from reversible magnetization measurements. It was found that the upper critical fields $H_{c2}$ were decreased for both H // c and H // ab as Al is substituted for Mg. As a result, the large anisotropy of $H_{c2}$ observed in pure $MgB_2$, which is considered as one of the characteristics of two-gap superconductor, was decreased with Al doping. On the other hand, the irreversibility fields $H_{irr}$ were increased for x = 0.1 and were significantly decreased for x = 0.2. In contrary to the anisotropy of $H_{c2}$, the anisotropy of $H_{irr}$ was increased as Al concentration increases.

Anisotropy of the Upper Critical Fields in Al-Substituted MgB2 Single Crystals

강병원,김헌정,Hyun-Sook Lee,이성익 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.52 No.5

The temperature dependence of the upper critical fields, Hc2, was deduced from magnetization measurements of high- quality Mg1..xAlxB2 single crystals along the two main crystallographic directions. We found that the strong temperature dependence of the anisotropy of Hc2 ( H = Hab c2=Hc c2) in pure MgB2 was drastically affected by Al doping. H(T) systematically decreased and as a result, H for x = 0.2 became nearly temperature independent. The diminished temperature dependence of H with Al doping is attributed to an enhanced anisotropic impurity scattering, which makes the bands less anisotropic.