• Archives of Pharmacal Research
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• v.21 no.5
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• pp.595-598
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• 1998

The rate of the GSH conjugate formation, the inhibition of DNA topoisomerase-I and the cytotoxic activity against L1210 cells of the naphthoquinones showed the same order; 5,8-dimethoxy-1,4-naphthoquinone (DMNQ)>6-(1-hydroxyethyl)-DMNQ>2-(1-hydroxyethyl)-DMNQ; the steric hindrance of the substituents, particularly 2-substutuent, in reacting with cellular nucleophiles must be the main cause for lowering the bioactivities. Acetylation of 2-(1-hydroxyethyl)-DMNQ producing 2-(acetyloxyethyl)-DMNQ potentiated the bioactivities; 2-(-hydroxyethyl)-DMNQ did not react with GSH and the enzyme, and showed $ED_{50}$ of 0.146 mg/ml for the cytotoxcity. Furthermore, the acetylation 2-(1-hydroxyethyl)-DMNQ(T/C, 119%) enhanced the T/C values for the mice bearing S-180 tumor {T/C of 2-(1-acetyloxyethyl)-DMNQ, 276%]. It was assumed that the difference in bioactivities ensued by acetylation was based on the mechanism of the so-called bioreductive alkylation.

• Proceedings of the KWS Conference
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• 2007.11a
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• pp.215-217
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• 2007

철계 피삭재 가공 시 적용되는 cBN(cubic Boron-Nitride)의 경우 열적/구조적 안정성으로 인해 융착 시 계면에서 화학적 결합이 어려워, 지립이 단일층으로 형성되어야 하는 융착 공구의 경우 적용되질 못하고 있다. 이러한 문제를 해결하기 위해 세라믹과의 젖음성이 우수한 Ti 성분이 포함된 67Ag+28Cu+5Ti(wt.%) 조성의 합금분말을 이용하여 cBN을 접합을 하였으며, 이때 융착조건은 진공 분위기($6{\times}10^{-6}$Torr), $900^{\circ}C$ 온도에서 5분간 유지하여 융착을 실시하였다. 본 연구의 주목적은 Ti 합금화 된 Ag계 합금분말 및 cBN의 융착 계면에서의 융착 계면거동해석을 통한 건전한 접합공정을 찾는데 있다. 이에 온도 $900^{\circ}C$, 유지시간 5분에서 건전한 융착층을 형성함을 알 수 있었다. 또한 결합력 측정기를 이용하여 결합력을 측정한 결과 diamond와 융착하였을 때가 123N, cBN을 융착하였을 때 107N으로써, cBN 융착이 diamond 융착의 87%정도의 결합력을 보임을 알 수 있었다. 한편 cBN과 Ag-Cu-Ti계 브레이징 필러의 계면에서의 미세조직 및 화학반응의 메커니즘은 SEM, EDS를 이용하여 분석하였다.

• International Journal of Aeronautical and Space Sciences
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• v.12 no.4
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• pp.365-370
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• 2011

This paper presents the air-to-air missile autopilot design for a $180^{\circ}$ heading reversal maneuver during boost-phase. The missile's dynamics are linearized at a set of operating points for which angle of attack controllers are designed to cover an extended flight envelope. Then, angle of attack controllers are designed for this set of points, utilizing a pole-placement approach. The controllers' gains in the proposed configuration are computed from aerodynamic coefficients and design parameters in order to satisfy designer-chosen criteria. These design parameters are the closed-loop frequency, damping ratio, and time constant; these represent the characteristics of the control system. To cope with highly nonlinear and rapidly time varying dynamics during boost-phase, the global gain-scheduled controller is obtained by interpolating the controllers' gains over variations of the angle of attack, Mach number, and center of gravity. Simulation results show that the proposed autopilot design provides satisfactory performance and possesses good [ed: or "sufficient" or "excellent"] capabilities.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2003.11a
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• pp.48-53
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• 2003

The high temperature melting test for nonflammable wastes using a plasma torch was conducted. The AP-200L hollow cathode type plasma torch was installed at the pilot plasma melting furnace in NETEC. The surrogates were prepared to simulate concrete, soil and their mixture with steel. The experimental conditions such as feeding rate, the distance between melts surface and torch nozzle, torch rotation speed, gas flow rate and pressure in the furnace were decided. Basic parameters such as temperatures of cooling waters, off-gas and torch power were measured. The vitrified samples were analyzed by SEM/EDS.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2009.05a
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• pp.421-424
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• 2009

Superplastic deformation behavior and texture evolution after equal channel angular pressing (ECAP) of Zn-0.3Al alloy were investigated in this study. ECAP was conducted at temperatures from $40^{\circ}C$ to $160^{\circ}C$ on the plate type specimens of 5 mm thickness and 20 mm width. The specimens obtained by ECAP showed typical texture with basal poles tilted away from the ND toward ED. A series of compression and tensile tests was carried out at temperatures from RT to $200^{\circ}C$ under the strain rate from 0.03 to 10/s. After ECAP of the Zn-Al alloy, elongation was dramatically increased up to 1000% at above $60^{\circ}C$. The effects of ECAP on the texture and anisotropy in the superplastic deformation bebavior were found to be negligible.

• Korean Journal of Veterinary Research
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• v.39 no.3
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• pp.538-544
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• 1999

To elucidate the involvement of interleukin-$1{\beta}$ converting enzyme (ICE) in the course of experimental autoimmune encephalomyelitis (EAE), we induced EAE by immunizing rats with an emulsion of rat spinal cord homogenate with complete Freund's adjuvant supplemented with Mycobacterium tuberculosis (H37Ra, 5mg/ml) and then examined the expression of ICE in the spinal cord of rats with EAE. In normal rat spinal cords, ICE is constitutively, but weakly, expressed in ependymal cells, neurons, and some neuroglial cells. In EAE, many inflammatory cells are positive for ICE, and the majority of ICE+ cells were identified as ED1+ macrophages. During this stage of EAE, the number of ICE+ cells in brain cells, including neurons and astrocytes, increased and these cells also had increased ICE immunoreactivity. These findings suggest that the upregulation of ICE in both brain cells and invading hematogenous cells is stimulated by a secretory product from inflammatory cells, and that this enzyme is involved in the pathogenesis of EAE via the production of IL-1 beta.

• The Journal of Korean Obstetrics and Gynecology
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• v.18 no.4
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• pp.1-9
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• 2005

Purpose : 이 연구는 SKBR3 인간 유방암 세포주에 대한 Euonymus alatus (Thunb.) Sieb 추출물 (CWE) 의 증식억제, 항산화 작용 및 세포사 유발 효과를 검토하기 위해 이루어 졌다. Methods : SKBR3 세포주는 48시간 동안 다양한 농도 ($0-40\;{\mu}g/ml$)의 CWE를 첨가하면서 배양되었고, 세포의 생존 비율은 MTT 배양을 통해서 평가하였다. 또한 CWE의 증식억제 효과는 유방암 세포주의 세포사와 관련되어 있음을 형태학적인 변화와 올리고뉴클레오솜 DNA 분절을 통해 확인하였다. Results : CWE의 50%에서 효과를 나타내게 하는 약물농도인 $ED_{50}$ (effective dose 50%)은 $9.3+2.2{\mu}g/ml$이며, 약물의 농도에 의존하여 세포의 증식을 억제시켰다. 아울러, 다양한 농도와 배양시간에서 CWE가 ROS 생산을 억제하는 것을 밝힐 수 있었다. 따라서 이러한 작용과 항암예방효과는 농도와 노출 시간에 의존하였다. Conclusion : 이러한 관찰을 통해 Euonymus alatus (Thunb.) Sieb의 열수 추출물은 SKBR3 인간 유방암 세포주에 대해 강한 증식억제 효과와 강력한 항산화효과 및 세포사의 유발 효과를 가지는 것으로 인식할 수 있다.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.19 no.3
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• pp.353-362
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• 2012

Purpose: The objective of this study was to examine the correlation between HbA1C, self-care behavior, and quality of life among depressed and non-depressed patients with type II diabetes Methods: Data were collected between May 26 and July 5, 2011 using a questionnaire. The questionnaire included depression (CES-D), self-care behavior and quality of life. Hemoglobin A1C was ed from medical records. Data were analyzed by descriptive statistics, t-test, $x^2$-test, ANCOVA and Pearson's correlation coefficient. Results: In this study sample (n=301), 20.9% of diabetic patients (n=69) were depressed. After adjustment for relevant covariates, depressed patients showed to have lower self-care behavior (2.8 vs 3.4, p<.001) and quality of life (2.8 vs 3.5, p<.001) scores, but the difference in HbA1C was no longer significant. Conclusion: This study suggests that the assessment and intervention for depressed diabetic patients can result in effective self-care behavior, which accordingly leads to improvement of the quality of life.

• Journal of the Korean Home Economics Association
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• v.33 no.3
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• pp.1-16
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• 1995

The purposes of this study were to : (1) examine current curricula related to home economics in university liberal education curriculum, (2) identify the educational needs on fields and contents related to home economics in college-level liberal education curriculum perceived by university students and professors, (3) provide the findings to make recommendations for development of liberal subjects related to home economics in university liberal education curriculum. This study was conducted by means of the review of literatures and the questionnaire survey. the instruments for the survey was developed by the researcher, the one was for students and the other was for professors. They included items of needs about 6 fields related to home economics and 8 contents each, and there were items of reasons for needs about each fields. The samples for the analysis were 284 university students in Seoul, and 176 university professors of all over the country. The research findings were as follows : 1. There were differences between current curricula and students' needs related to home economics in university liberal education curriculum. 2. There were much more subjects related to home economics in woman's university than in co-ed. university. 3. Students needed such fields as follows : (1) maintenance of individual and family relation, (2) human development, (3) home management and consumer education 4. The reason why students needed the subjects was that they could be helpful to solve the problems of everyday life. 5. The reason why professors needed the subjects was that they could be useful to prepare for the future of every student.

• Journal of Families and Better Life
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• v.21 no.2
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• pp.117-130
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• 2003

This study was conducted to examine elderly users' satisfaction with welfare services and the environments of the senior citizen centers in mid-sized and small cities in Korea. Three hundred and two elderly users were surveyed for this study. Age and gender differences in the level of satisfaction were found. The male elderly users and older users were more satisfied with the education programs than the female and younger users. The elderly people who reside in single-family residences were more satisfied with the educational programs and part-time job opportunities offered at the center than the elderly users who were living in apartment buildings. This could be explained by the fact that dwellers of single housing had more freedom and more room for self-regulation in scheduling their program participation, whereas the apartment building residents had rarely experienced social exchanges with their neighbors. There were significant differences in satisfaction with the environments of the centers by gender, marital status, age, level of education, religion, and housing type. The group differences were explained by the abundance of community activities that are centered around younger and female participants. Based on these findings, it is suggested that more specialized educational and social programs should be developed for the younger users in their early 60s, that co-ed religious activities and hobby programs should be expanded, and that the home-visiting welfare staff should regularly provide the elderly users the information on programs and activities.