난소절제후 Estrogen을 투여한 흰쥐 대동맥에서 Protein Kinase C-α와 Fas 발현의 변화

이왕수,이상엽,안지현,송영빈,김학진,이광재,유재격,김상욱,김태호,김치정,류왕성 중앙대학교 의과대학 의과학연구소 2001 中央醫大誌 Vol.26 No.3

Estrogen is believed to decrease coronary artery disease. Protein kinase C-α(PKCα)appear to be important in signal conduction pathways. Estrogen treatment increases catalytic activity of PKCα,and activation of PKCαcan modulate estrogen receptor levels and responsiveness. And it was reported that activation of PKC can protect cells from apoptosis induced by Fas ligation. But the beneficial effect of estrogen on PKCαwas not clearly demonstrated. The objective of this study was to evaluate the role of PKCαafter ovariectomy and estrogen therapy in rat aorta. The results were summarized as below: 1. The significant pathological changes were not observed in the rat aorta irrelevant to ovariectomy and estrogen therapy. 2. The expression of Fas was decreased in the aorta of estrogen-treated rats than that of ovariectomized rats without estrogen therapy. 3. Increased expression of PKCαwas more marked in the aprta of estrogen-treated rats than that of ovariectomized rat without estrogen therapy. In conclusion,PKCαmay be important in signal conduation pathway on the effect of estrogen. Activation of PKCαby estrogen reduced Fas expression, suggesting that PKCαactivation may play a role in protection against atherasclerosis. Further studies are needed to elucidate the role of PKCαafter estrogen therapy.

A field study of colloid transport in surface and subsurface flows

Zhang, Wei,Tang, Xiang-Yu,Xian, Qing-Song,Weisbrod, Noam,Yang, Jae E.,Wang, Hong-Lan Elsevier, etc 2016 Journal of hydrology Vol.542 No.-

<P><B>Abstract</B></P> <P>Colloids have been recognized to enhance the migration of strongly-sorbing contaminants. However, few field investigations have examined combined colloid transport via surface runoff and subsurface flows. In a headwater catchment of the upper Yangtze River, a 6m (L) by 4m (W) sloping (6°) farmland plot was built by cement walls to form no-flow side boundaries. The plot was monitored in the summer of 2014 for the release and transport of natural colloids via surface runoff and subsurface flows (i.e., the interflow from the soil-mudrock interface and fracture flow from the mudrock-sandstone interface) in response to rain events. The water sources of the subsurface flows were apportioned to individual rain events using a two end-member model (i.e., mobile pre-event soil water extracted by a suction-cup sampler <I>vs</I>. rainwater (event water)) based on <I>δ</I> <SUP>18</SUP>O measurements. For rain events with high preceding soil moisture, mobile pre-event soil water was the main contributor (generally >60%) to the fracture flow. The colloid concentration in the surface runoff was 1–2 orders of magnitude higher than that in the subsurface flows. The lowest colloid concentration was found in the subsurface interflow, which was probably the result of pore-scale colloid straining mechanisms. The rainfall intensity and its temporal variation govern the dynamics of the colloid concentrations in both surface runoff and subsurface flows. The duration of the antecedent dry period affected not only the relative contributions of the rainwater and the mobile pre-event soil water to the subsurface flows but also the peak colloid concentration, particularly in the fracture flow. The <10μm fine colloid size fraction accounted for more than 80% of the total suspended particles in the surface runoff, while the colloid size distributions of both the interflow and the fracture flow shifted towards larger diameters. These results highlight the need to avoid the application of strongly-sorbing agrochemicals (e.g., pesticides, phosphorus fertilizers) immediately before rainfall following a long no-rain period because their transport in association with colloids may occur rapidly over long distances via both surface runoff and subsurface flows with rainfall.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Subsurface flow was apportioned into rainwater and mobile pre-event soil water. </LI> <LI> The duration of no-rain period affects peak colloid concentration. </LI> <LI> Rainfall intensity and its temporal variation govern colloid discharge dynamics. </LI> </UL> </P>

빔 구조물의 손상평가를 위한 임피던스 기술의 응용

홍동표,홍용,왕고평,김병진,김영문,이재정,김재열 한국공작기계학회 2006 한국공작기계학회 추계학술대회논문집 Vol.2006 No.-

This paper presents a primary study for a new method of enhancing measurement using impedance analysis method, which is widely used for structure health monitoring. Many of skyscrapers, bridges, tunnels, which have been built up several years, and nearly reached their operating life due to aging crack, material deterioration, and so on. therefore, the health monitoring technique has obtained considerable attention. The goal of this research is to show basic information to evaluate structural health condition using piezoelectric sensors. The piezoelectric materials have various merits. It is easy to shape various forms and can be embedded on the materials more conveniently. Moreover, the excitation frequency can be changed and the piezoelectric sensors cost less. All these features make the piezoelectric-based system applicable to structural healthy monitoring. This work presents a study for the development of a practical and quantitative technique for assessment of the structural health condition by piezoelectric impedance-based technique associated with longitudinal wave propagation. To estimate the damage condition numerically, we suggest the evaluation method Cov (Covariance) and CC (Correlation Coefficient) in this paper.

와이어컷 방전에 의한 합금공구강과 초경합금의 북현상에 관한 연구

김원일,왕덕현,이재명 慶南大學校 附設 工業技術硏究所 1997 硏究論文集 Vol.14 No.2

와이어컷 방전가공에서 합금공구강과 초경합금을 대상으로 여러가지 방전인자가 북현상에 미치는 영향을 관찰하였다. 북현상은 방전극간전압과 방전주기가 작고, 두께가 얇고 와이어장력이 크며, 가공횟수를 많이 할수록 줄어든다. 두께 60mm초경합금을 보통의 조건으로 가공하면 전해작용에 의해 결합제인 코발트가 용출되어 주성분인 탄화텅스텐이 탈락되어 북현상이 커지므로 전도도를 낮게 해야한다. From the experimental study of wire-cut Electric Discharge Machining for alloyed steel and tungsten carbide, the characteristics such as hand drum form has been observed and evaluated for various conditions. Hand drum form can be improved when gap voltage and spark cycle become smaller, their thickness become thinner, wire tension become larger and no. of cuttings is done so many times. When wire-cut 60mm thickness tungsten carbide in normal condition. Hand drum form becomes larger due to the low conductivity inducing cobalt composite rising by electrolysis.

가속도 전향보상을 이용한 유도전동기의 속도제어

김상훈,이재왕 강원대학교 산업기술연구소 2000 産業技術硏究 Vol.20 No.B

In this paper, a novel speed control strategy using an acceleration feedforward compensation by the estimation of the system inertia is proposed. With the proposed method, the enhanced speed control performance can be achieved and the speed response against the disturbance torque can be improved for the vector-controller cannot be made large enough. The experimental results confirm the validity of the proposed strategy.

중합체 복합재료의 드릴가공시 발생하는 적층분리

김원일,왕덕현,이윤경,이재만,신경오 경남대학교 신소재연구소 1997 論文集 Vol.9 No.-

다방향 적층구조 중합체 목합재료의 드릴가공시 발생하는 적층분리 현상에 대해서 절삭속도 및 이송속도의 변화시키면서 실험적 연구를 진행하였다. 드릴가공시 발생되는 재료거동의 탄성파의 변형을 시편의 측면에서 음향방출신호로 측정하였으며, 광학현미경과 전자현미경으로 적층분리된 측정값과 표면거칠기 측정에서 얻은 결과를 얻어 비교하였다. 음향방출 신호로 측정한 결과와 공구현미경의 실제측정값 및 표면거칠기에서 적층분리가 발생한 지점이 거의 일치함을 확인하였다. 본 실험결과 드릴공구로 사용된 소결합금 공구는 이송속도가 낮고 절삭속도를 큰 경우 적층분리 현상을 억제하여 양호한 가공면을 얻을 수 있었다. An experimental study on the delamination phenomena during drilling of laminate polymer composites, was conducted according t o the change of cutting speed and feed rate. The analysis of acoustic emission signals was in good agreement with measured values by optical microscopy. And also the surface roughness characteristics of workpiece in drilling was accumulated and compared. It was found that the delamination location measured by AE signals and real measurement values by tool microscope are almost same. The better surface and prevention of delamination was obtained by the slight increase of cutting speed and the decrease of feed rate when sintered tool was used.

흰쥐에서 염화비닐 폭로수준에 따른 소변내 thiodiglycolic acid 농도의 변화

왕승준,차봉석,노재훈,신동천,김명수,전근재 大韓産業醫學會 1999 대한직업환경의학회지 Vol.11 No.4

Objectives : It is the objective of this research to identify the variation of thiodiglycolic acid(TdGA) in urine with vinyl chloride monamer(VCM) exposure levels through methylation. Methods : After rats were exposed to vinyl chloride monomer of 4 levels, 0㎎/㎥, 50㎎/㎥, 150㎎/㎥, 500㎎/㎥, respectively, of which urine was sampled in each sampling time of 0 hour, 2 hours, 4 hours, 8 hours, 16 hours, 36 hours, 48 hours. After urine had been methylated with diazomethane in the preliminary experiment and the peak of 146 m/z had been verified, the main experiment was done. Results : In the variation of TdGA with sampling times, concentration of TdGA increased rapidly in 4 hours and then decreased after 8 hours. When the variation of urinary TdGA concentration in urine according to exposure level of VGM was verified through Kruskal-Wallis statistical method at each sampling time, the significant increment with the exposure levels at 2 hours, 4 hours, 8 hours after exposure was clarified. Conclusion : TdGA concentration in urine with increment of VCM exposure level increased, especially significantly at 2 hours, 4 hours, 8 hours of sampling time.

치료 불응성 Still's병에서 자가 조혈모세포 채집시 사용된 G-CSF에 의한 급성 악화 1예

이재웅,박성현,왕준광,오호석,최정혜,배상철,이영열,김인순,최일영,안명주 대한조혈모세포이식학회 2003 대한조혈모세포이식학회지 Vol.8 No.2

치료 불응성 자가면역질환에서 고용량 항암화학요법 및 자가 조혈모세포이식술이 시행되고 있으나 조혈모세포 가동화 및 이식술 시 사용되는 G-CSF에 의해 오히려 기존의 자가면역질환의 증세가 악화되었다는 보고가 있다. 저자들은 만성적으로 재발되는 Still's병 환자에서 조혈모세포 가동화를 위해 사용한 G-CSF에 의해 자가면역질환이 급성 악화된 1예를 경험하였기에 보고하는 바이다. High-dose immunosuppressive therapy with autologous stem cell transplantation is an increasingly used treatment for severe refractory autoimmune disorder including multiple sclerosis, rheumatoid arthritis, juvenile chronic arthritis, systemic lupus erythematosus. Although the optimal method of collecting stem cell is not determined, G-CSF-based mobilization is generally considered safe. However, worsening of disease status was reported in autoimmune disease undergoing mobilization with G-CSF. We report a 24-year-old male with refractory Still's disease who developed acute disease flare after administration of G-CSF for stem cell mobilization.

목원대학교 건축·도시공학부 발전방향에 관한 연구

이재연,최봉문,김도식,이왕기 牧園大學校 建築·都市硏究센터 1999 建築·都市環境硏究 Vol.7 No.-

School of Architecture and Urban Engineering, Mokwon University, was chosen the specialized school in Mokwon Univ. and has been receiving the National Strategic Financial Support(NSFS), by the Ministry of Education, Since 1997. This study was carried on for a part of NSFS programs. The objective of this study is to propose the new Educational Programs and development plannings for School of Architecture and Urban the Engineering for the specialized school in Mokwon University. This paper is the Summary of the whole study.

Polylysine을 입힌 배양면이 GH₃ 뇌하수체 종양 세포에 미치는 영향에 관한 연구

김정진,백상호,황덕호,황영일,이왕재,이병란 대한해부학회 1998 Anatomy & Cell Biology Vol.31 No.3