요중 비소농도와 N-acetyl-β-D-glucosaminidase 농도와의 관련성 평가

이용찬,임동혁,엄상용,김용대,김헌 충북대학교 의과대학 충북대학교 의학연구소 2010 忠北醫大學術誌 Vol.20 No.1

Purposes: This study was performed to evaluate the possibility of impairment of renal tubular function by exposure to inorganic arsenic of low concentration. Materials and methods: Study subjects were 867 individuals (365 men and 502 women) who resided around abandoned mine areas in Chungbuk Province, Republic of Korea. Information about the life style, drinking water type, seafood intake, and mine working history was gathered, and urinary arsenic concentration and N-acetyl-β-d-glucosaminidase (NAG) activity were measured. The correlation between arsenic concentration and urinary NAG activity was tested in groups classified according to urinary NAG activity and seafood consumption prior to urine sampling. Results: No statistically significant difference in urinary arsenic concentrations was observed between different gender and age groups. The participants those who ate seafood within three days before the urinary sample showed a higher mean urinary arsenic concentration than those who did not. In a correlation analysis between natural logarithm of urinary arsenic concentrations and that of urinary NAG activities, no statistical significance was found in a total sample as well as within a gender group. In a group with the urinary arsenic concentrations higher than the geometric mean and the urinary NAG activities higher the geometric mean, the correlation coefficient between two variables was 0.182 and significant. (p-value<0.05) Conclusions: It is suggested that renal tubular damage could be induced by non-occupational exposure to low level inorganic arsenic. 연구목적 : 본 연구는 폐금속광산 주변지역 주민들을 대상으로, 저농도 비소노출에 의하여 신세뇨관 기능이상이 유발될 수 있는지를 평가하는 것을 목적으로 시행하였다. 대상 및 방법 : 충청북도에 소재하고 있는 폐금속광산의 주변에 거주하는 주민 867명을 대상으로 직접 면접조사를 실시하였다. 대상자의 소변을 채취하여 요중 비소농도와 요중 N-acetyl-β-D-glucosaminidase (NAG) 활성을 측정하였고, 조사대상자를 역학적 변수에 따라 구분하여 두 변수 사이의 상관관계를 분석하였다. 결과 : 소변시료를 채취하기전 3일 이내에 해산물을 섭취한 사람들의 요중 비소농도는 그 기간동안 해산물을 섭취하지 않은 사람들의 농도에 비하여 유의하게 높았다. 조사 대상자들의 요중 NAG 농도의 평균값은 남녀차이가 없었으나, 65세 미만 대상자와, 표본을 채취하기 전 3일 이내에 해산물을 섭취한 사람들의 요중 NAG 활성도의 평균값은 그렇지 않은 사람들에 비하여 유의하게 낮았다. 요중 비소농도가 기하평균 이상이고, 요중 NAG 활성이 기하평균 이상인 군에서 두 변수의 상관관계가 0.182 로 유의하였다. 결론 : 정상범위의 비소 노출이라도 요중 비소농도가 8.28 μg/g creatinine을 초과하는 경우에는 미세한 신장손상을 유발할 가능성이 있으며, 해산물을 섭취함으로써 체내에 흡수되는 비소는 이러한 신독성이 거의 없다.

成分檢出에 의한 오수유의 確認

엄동욱,김용성,신태용,도경삼 우석대학교 생명과학연구소 1998 생명과학연구소 논문집 Vol.2 No.-

Evodiamine and evocarpine are basic components to contain in Evodiae Fructus. After Evodiamine and evocarpine heve been isolated from the Evodiae fructus as the precipitate, they could be identifified and separated by coloured test, UV/Vis. absorption wavelength or TLC The presence of evodiamine and evocarpine are confirmed by its reaction with the TCR ion, [Co(SCN)_4]^2-, to produce the blue or yellowish blue precipitate, It is based on the formation of complex compounds by evodiamine and evocarpine with TCR reagent. The method has been found to be simple, convenient and suitable for routine identification of evodiamine and evocarpine, related basic constituents, the crude drug "Evodiae fructus" prepared from the Evodia officinalis Dode or Evodia rutaecarpa Bentham(Rutaceae).

LUR'E 판별법과 Tzypkin 판별법의 유도

엄기환,박장환,이용구 동국대학교 산업기술연구원 1995 산업기술논문집 Vol.6 No.-

Lur'e 판별법으로부터 비선형소자 포화를 갖는 이산제어시스템의 안정도를 위한 Lyapunov 함수를 구성하고 이를 안정도 판별에 활용했다. 연속시스템에서의 Lur'e 판별법을 근거로 Popov 판별식이 유도되어지는 것과 같이, 이산 제어 시스템에서는 비선형소자 포화를 이산화함으로써 Zypkin 판별법이 유도되어 질 수 있었다. 시간영역과 주파수영역 사이의 안정도관계는 Lyapunov 함수의 존재를 근거로 하여, Kalman-Szego¨ 보조정리와 Zypkin 판별법을 유도하였다. In this paper, it is shown that the construction and application of Lyapunov-function for stability of non-linear discrete control system within on-linearity "saturation" from Lur'e-Criterion. The derivation of Popov-criterion is based on the Lur'e-criterion. In discrete control system, the derivation of Tzypkin-criterion is possible to discrization non-linearity element "saturation". Kalman-Szego¨-lemma and Tzypkin-criterion which the stability relationship between frequency domain and time domain representation, is derived based on the existence of Lyapunov-function.

콩 미이라병의 유전적 분리

엄상미,윤홍태,김용호 순천향대학교 기초과학연구소 2003 순천향자연과학연구 논문집 Vol.9 No.2

Phomopsis seed decay (PSD) is a major fungal disease found in most soybean production areas of the world. PSD significantly reduces soybean yield and seed quailty, particularly when soybean plants are exposed to high humidity and high temperature during maturation. To certificate genetic segregation ratio for PSD, PI 417479 line(resistant) and Hwaeomputkong(susceptible) were crossed and examined their inheritance mode. Experiment was conducted at glasshouse of Soonchunhyang Univ., in Korea. Different PSD seed infection levels were induced in soybean seeds by artificially infected plants exposing to above 95% relative humidity and 30˚C. A sample of seeds harvested from inoculated plants was analyzed to determine percent PSD incidence. The patterns of resistant response between Hwaeomputkong and PI 417479 were different in their seed and pod shape. The F₁plants of the resistance is governed by the two dominant genes. This results indicate that a resistance to PSD is controlled by complementary genes.

Baicalin 含有 제제의 生體利用率에 關한 硏究

엄정신,김영일,남용옥,양재헌 우석대학교 의약품개발연구소 1997 藥學硏究誌 Vol.2 No.-

In order to increase bioavailabilities of Scutellariae Radix extract(SRE), very slightly soluble in oil phases and sparingly soluble in water phases, the preparation of emulsification was attempted. In previously studies in O/W and W/O forms emulsion, the stabilities were evaluated for each forms. In this study, the dissolution and bioavailabilies of each emulsion preparation of SRE were compared. The dissolution pattern of SRE in W/O emulsion was decreased more than O/W emulsion in dilute hydrochloric acid solution(pH1.2) and in phosphate buffer solution(pH 6.8). The absorption velocity of baicalin from W/P emulsion was slower than O/W emulsion. The absorption velocity of baicalin in stomach was slower than in duodenum and jejunum of rats. The time required for the maximum serum concentration (C_max) of baicalin from water phase, oil phase, O/W and W/O emulsion in mice were 30. 60, 90, and 120 minutes after oral administration respectively. The C_max of baicalin from water phase, oil phase, O.W and W/O emulsion in mice were 2.11, 0.61, 1.57, and 1.35 ug/ml respectively. The longer was the time required for C_max, the lower was C_max. If the bioavailability to water phase is 100, the relative bioavailability(RB) to W/O emulsion is 129.14 The result suggests that the improvement of bioavailability for baicalin in W/O emulsion might be practically available.

자기동조 레귤레이터의 비선형성 보상을 위한 새로운 신경회로망 제어방식

엄기환,이용구,정성부,김진식 東國大學校 1996 東國論叢 Vol.35 No.-

In this paper, we propose a new controller design method that can get good control performance and reduce computation by loosing to small step size of conventional STR, owe to adding a neural network controller in STR with parallel for compensating for STR's nonlinearity. Through having tested the validity of the proposed controller by one link manipulator simulation and experiment, we compare with control performance for convention-al STR

DSP를 이용한 간단한 Controller Board의 설계

嚴基煥,李鎔求 東國大學校 1994 東國論叢 Vol.33 No.-

This paper deals with a design of a DSP Board for solving real-time digital control problems. A DSP Board is composed of TMS320C31, AD1678, AD565A, and 8255A. A Designed DSP Board is suitable for accuracy control and is easy to make a control systems. A DSP Board is fabricated, which is demonstrated by the speed and position control of a DC Servo Motor using the Self-Tuning control algorithm.

최대밀도점 부근의 물 속에 잠겨있는 등온 수직 긴원기둥에 의한 자연대류의 실험적 연구

엄용균,권승혜 安東大學校 工業技術硏究所 1996 공업기술연구논문집 Vol.3 No.1

An experimental study of the free convection due to a isothermal vertical long cylinder immersed in water near its density extremum has been carried out. The surface temperature of the cylinder is 0℃, the aspect ratio is 4.8×10^(-2). Time-exposure photographs of the buoyancy-driven flow adjacent to a vertical cylinder in pure water are presented for adjacent water temperatures between 2.0 and 10℃. These conditions are of special interest since between 2.0 and 10℃ the buoyancy force distribution id locally bi-directional across the thermal transport region, Oweing to the density extremum at about 4℃. Resurts of the visualization show three distinct flow regions: upware flow for 2.0℃≤T_(∞)≤4.3℃, downward flow for 5.8℃≤T_(∞), dual flow for 5.6℃<T_(∞)<5.8℃ and unsteady atate flow for 4.3℃<T_(∞)≤5.6℃. The temperature range which the upward flow regions appeared is the same with those of short cylinder, but the temperature which the dualflow region and the downflow region occur is lower than those of short cylinder. Mean Nusselt numbers were smaller at unsteady state region than at the other regions. In the downward flow region, mean Nusselt number increase with increasing the surrounding temperature. In the upward flow region, mean Nusselt number increase and decrese with increasing the surrounding temperature, so there are maxmum Nusselt number at T_(∞)=3.0℃. Comparion of mean Nusselt number with past theoretical study shows good agreement

역전파 신경회로망을 이용한 자기동조 적응제어

엄기환,손동설,박장환,이용구 동국대학교 산업기술연구원 1995 산업기술논문집 Vol.6 No.-

역전파 신경회로망을 추정기로 이용한 자기동조 적응제어방식을 제안하였다. 제안한 방식은 역전파 신경회로망을 이용하여 시스템함수를 추정하고 추정된 함수를 제어기에서 이용하는 자기동조 적응제어 기법이다. 제안한 방식의 유용성을 확인하기 위하여 가동코일형 선형 직류전동기를 제어대상으로 기존의 반복 최소 자승법을 이용한 자기동조 적응제어방식과 시뮬레이션 및 실험을 통하여 추종 특성을 비교 검토하였다. This paper proposes the self-tuning adaptive control method with back-propagation neural network using a identifier. A proposed method is self-tuning adaptive control method that estimates system functions using back-propagation neural network and estimated function is used to controller. In order to verify the usefulness of proposed method, tracking control characteristics are compared the general self-tuning adaptive control method using R.L.S by simulation and experiments.

이동 컴퓨팅 환경에서 이동 호스트들에 대한 동적 세션 관리 기법

강용혁,김문정,엄영익 成均館大學校 科學技術硏究所 2000 論文集 Vol.51 No.1

Recently, the technical advances in wireless communication technologies and the decreasing size of computer components increase the number of mobile users. In the mobile computing environments wireless links are very restricted resource, so efficient use of wireless links is the heart of an efficient mobile computing environments. This paper proposes a scheme for load reduction of foreign agent by managing the number of registered mobile hosts in a cell. This scheme presents the efficient use of wireless links without the channel rearrangement. Experimental results show that the proposed scheme reduces the number of registered mobile hosts in a cell in proportion to the cell redundancy.