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.

주식시장간 수익률 전이

정헌용 남서울대학교 2012 남서울대학교 논문집 Vol.18 No.2

The purpose of this study is to examine the relevence of return among stock markets in countries. We use Granger causality test to examine the revelence existing in 9 Asian countries and U.S.A. before and after 1997 Asian financial crises. As a result, first, in the total period, US stock market return transmitted to Japan, Korea, Hong Kong, and Singapore stock markets. Japan stock market return transmitted to US, Singapore, and Indonesia stock markets. And Korea stock market return transmitted to US, Malaysia, Indonesia, and Thailand stock markets. Second, in the before Asian financial crises period, we do not find the relevence of return among stock markets in countries. Third, in the after Asian financial crises period, US stock market return transmitted to Japan, Korea, Hong Kong, and Singapore stock markets. Japan stock market return transmitted to US, Hong Kong, and Singapore stock markets. And Korea stock market return transmitted to US, Hong Kong, Malaysia, Indonesia, and Thailand stock markets. The results suggest substantial increased Asian stock market comovement. This implies that the benefits of diversification within the 9 Asian stock markets have decreased over the recent years. Key Words : Granger causality, KOSPI, return spillover

상해증권거래소의 거래제도와 특성

정헌용 남서울대학교 2011 남서울대학교 논문집 Vol.17 No.2

The Shanghai Stock Exchange(SSE) is the most preeminent stock market in mainland China in terms of listed companies, number of shares of listed, total market value, and securities turnover in value. SSE composite index takes December 19, 1990 as the base day and the total market capitalization of all the listed stocks on the same day as the base period, with a base of 100 points. It was published from July 15, 1991and is the most widely used index in China's securities market. We examine the daily stock returns over the eleven years from January 4, 2000 through December 30, 2010. Because of the test statistics of significant skewness, excess kurtosis, autocorrelations, it is reasonable to empoly GARCH models. We use the univariate GARCH(1,1)-M model developed by Engle et al.(1987).The results of the estimation of the GARCH(1,1)-M model for SSECI daily returns show that the risk premium effect on mean equation is not significant. Using the GARCH(1,1)-M model with exogenous variables, we find significant information spillover effect from KOSPI to SSECI and from SSECI to KOSPI in the mean equation. But we cannot find significant information spillover effect from KOSPI to SSECI and from SSECI to KOSPI in the variance equation. Key Words : SSE, SSECI, KOSPI, GARCH model, spillover effect

명태의 행동제어용 심전도 도출에 관한 연구

박용석,이창헌,이유철,서두옥 제주대학교 해양연구소 1997 해양자원연구소연구보고 Vol.21 No.-

In the walleye pollock. Theragra chalcogramma. which has a heart with a strong electromotive force, the ECGs were found to be recordable by electrodes placed in the water from fish's body. The day on the experiment, fish was operated on in order to install a leading-out bipolar electrode. This electrode was used for recording of the cardiosignal of the fish on a digital storage oscilloscope. The electrode was made from a fish book which was re-shaped according to the shaped of fish heart and body surface. This hook was then connected to the lead-code insulated with paint, and the connecting part was covered with paint. The pointed end was stripped off slightly for conduction of electricity and the another pointed edge was used for hooking the electrode into the chest cavity. QRS complex of the ECG was marked. The amplitude of QRS complex was about 0.1-lmV. This method enabled us to observe the heart beat rate of the walleye pollock under least disturbed state. Ordinary heart beat rate was not quite regular. Very slight stimulation was enough to bring about cardiac inhibition. which was also accompanied by a considerable reduction in the amplitude of the QRS. After rough treatment. such as sound stimulus or electric shock. the heart beat rate showed remarkable decrease. reaching a value a few times lower than the normal level.

동일가중 지수수익률의 효율성에 관한 실증연구

정헌용 남서울대학교 1998 남서울대학교 논문집 Vol.4 No.-

This paper tests for the relations between trading volume and subsequent returns patterns in individual securities' returns and the effectiveness of equal-weighed index return. I examine value-weighted index return versus equal-weighted index return with respect to unbiasedness of the market-adjusted abnormal returns. The data consist of weekly returns and trading volume for individual stocks in the KIS-SMAT file between 1980 and 1996. The results of this study suggest that abnormal returns estimated using the price index of Korean Stock Exchange are overestimated, while abnormal returns estimated using equal-weighted index return are not overestimated.

폐쇄성 황달에 대한 내시경적 비 담도 배액법(ENBD)의 효과

이헌영,김남재,정현용 충남대학교 의과대학 지역사회의학연구소 1995 충남의대잡지 Vol.22 No.2

To evaluate the clinical effects of ENBD in patients with biliary obstruction, 18 patients were included in this study. The results were as follows ; 1) The causes of obstructive jaundice in 18 patients, with performed ENBD were distal CBD cancer (3 cases), CBD stone with cholangitis (14 cases) and CBD stone without cholangitis (1 case). 2) The duration of ENBD was 12.5 days (8-20 days). 3) The positive results of bacteriologic culture via ENBD tube revealed 8 cases among 13 (61.5%). 4) Amory 15 cases with CBD stones, Basket removal (2 cases) and Mechanical lithotripsy (1 case) perfomed in 3 cases after EST and 4 cases had an operation after ENBD. Three patients with CBD cancer underwent ERBD. In conclusion, ENBD is a safe and effective noninvasive biliary drainage method for initial decompression of malignant or benign biliary obstruction with or without cholangitis (especially with).

괴사후성과 비괴사후성 간경변증에서 원인별 주석교질 (^99mTc-tin colloid) 간스캔의 차이

이헌영,허승식,이강욱,정현용,김삼용,신영태,김영건,노흥규 충남대학교 의과대학 지역사회의학연구소 1992 충남의대잡지 Vol.19 No.2

The differences of the liver scintigraphic features between postnecrotic and nonpostnecrotic liver cirrhosis were studied for 69 patients. Degrees of mottling and splenomegaly were no different between two groups but shrinked form was more frequent finding in postnecrotic type(23:10), and normal shape & enlarged left lobe with shrinked right lobe were relatively dominant in non-postnecrotic group(15:6, 10:2). Grade of extrahepatic uptake of ^99mTc-tin colloid was significantly higher in Child-Pugh B & C group than A group(p<0.05), but there was no difference between postnecrotic and non-postnecrotic groups. These will be important results on the dicision for the presence of cirrhosis according to the variable causes.

아가리쿠스버섯에서 분리한 조단백다당류의 막분리 및 분무건조 특성

홍주헌,윤광섭,최용희 한국식품저장유통학회 ( 구 한국농산물저장유통학회 ) 2004 한국식품저장유통학회지 Vol.11 No.1

η_(evap)분자량에 따라 다양한 생리활성을 나타내는 아가리쿠스버섯에서 분리한 조단백다당류를 고부가가치 기능성 소재로 개발하기 위하여 막분리 및 분무건조 공정에 따른 특성을 조사하였다. 아가리쿠스버섯 조단백다당류를 분자량 크기에 따라 여과하는 동안 공정온도에 따른 투과플럭스의 변화는 10 kDa와 150 kDa 모두에서 유사하였는데, 막분리 온도 및 압력이 증가함에 따라 비례적으로 증가하였으며,40℃에서의 투과플럭스가 가장 높았다. 시간에 따른 투과플럭스의 변화는 막분리 30분 경과시 급속히 감소하였으며, pore size가 10 kDadhk 150 kDa일 때 공정압력이 각각 1.2 kg_(f)/㎠ 와 2 kg_(f)/㎠에서 가장 높았다. 한외여과 후 아가리쿠스버섯 조단백다당류의 점도는 여과 전 13.9cP에서 여과후 10 kDa이하와 10∼150 kDa구간은 각각 10.8, 11.9cP로 점도가 저하되었으나, 150 kDa이상은 20.1cP로 점도가 증가되었다. 분자량 크기가 다른 3가지 분획물에 대한 분무건조 공정에서의 열효율성은 가열공기온도, 시료공급속도 및 농도가 증가할수록 열효율성이 증가함을 알 수 있었으며, 시료공급속도가 가장 중요한 영향인자임을 확인하였다. This study was conducted to investigate the characteristics of ultrafiltration and spray drying process for crude protein bound polysaccharide(CPBP) isolated from Agaricus blasei Murill. In ultrafiltraion process, the permeate flux increased with the increase of operating pressure and temperature. The permeate flux declined continuously while the fouling materials were accumulated on the membrane as the operation time increased. In comparing of raw CPBP and filtered CPBP, the viscosity of CPBP treated UF was decreased and AE value of treated samples was increased. Thermal efficiencies of spray drying process were increased by increasing inlet temperature, feed rate and feed concentration.

ROBOT식 多目的 播種機 開發

李鎔國,李大源,黃憲,吳永鎭 成均館大學校 科學技術硏究所 1992 論文集 Vol.43 No.2

Planting, transplanting, and harvesting are important processes for the successful production of farm products in Korea because those require the short term high labor intensity. In the automatic production system of the field or the green house, planting is the first process required to be automated considering subsequent operations such as transpalnting and harvesting. A proto type experimintal robotized seeder was designed and built to handle various sizes and shape of seeds. The developed seeder is automatically controlled with one chip micro-controller. System is composed of the transfer arm, pecker, and the equipments integrated with sensor such as hopper, feeder, counter, and shutter. System allows to control the number of seeds to be planted. Results of the developed experimental robotized seeder are as following : 1. For the adequate feeding and counting of seeds, components such as hopper, feeder, counter, and shutter were designed and built. 2. Kinematic motion of the transfer arm was analyzed and designed. 3. Picker was designed to dig and drop seeds into the soil by the open and close action of the bottom gate controlled by DC solenoid. Digging depth of the pecker was controlled by the transfer arm.

Aflatoxin B1에 대한 단클론 항체의 생성

김용대,김 헌 충북대학교 의과대학 충북대학교 의학연구소 1995 忠北醫大學術誌 Vol.5 No.1

Aflatoxin은 세계 여러 곳에서 식품에 오염되어 체내에 유입되고 원발성 간암 등의 치명적인 질환을 유발하는 맹독성 물질이므로 aflatoxin의 생물학적 모니터링에 이용될 수 있는 aflatoxin B1에 대한 새로운 단클론 항체를 개발하기 위하여 본 연구를 시행하였다. AFB1-BSA를 Balb/c 마우스에 면역시키고 형질세포종 세포주와의 세포융합 방법 등을 통해서 ABF1에 특이적인 단클론 항체 Ⅰ-D4와 Ⅲ-D2를 얻었으며 이것의 특이성을 조사하였다. 이 결과 Ⅰ-D4는 AFB1, AFB2, AFM1에 대해 비교적 특이성이 있었으며, Ⅲ-D2는 AFB1과 AFG1에 높은 특이성을 가지고 있는 것으로 나타났다. 따라서 본 연구에서 개발된 단클론 항체들은 생체 시료 속에 존재하는 여러 종류의 aflatoxin이나 그 대사산물을 측정하는데 유용하게 사용될 수 있을 것이다. Aflatoxins are highly carcinogenic agents consistantly found as contaminants in human food supplies in many areas of the world and epidemiologically linked to incidence of human primary liver cancer. But, there was no studies in biological monitoring to aflatoxin exposure in Korea nearly. So, in this study sntibodies against aflatoxin B1(AFB1) were obtaind from Bald/c mouse after immunization of AFB1 conjugated bovine serum albumin. The antibodies are the most specific to AFB1 and moderaterly specific to AFM1, AFG1. Therefore the monoclonal antibodies expect to use in manufacturing of immunoaffinity column for biological monitoring of aflatoxin exposure.