안동호 상류 운곡천의 이화학적 수질특성과 식물플랑크톤 군집 특성

이중복,이희무,이건주,박정원,박재충,김동걸,권기석 7개 국립대학교 환경연구 논문집 공동발행 위원회 2002 환경연구논문집 Vol.2 No.1

This investigation is about the characteristics of phytoplankton community and physciochemical water quality of specific 6-point the Woon-kog stream system in upsteam of the Andong Lake. DO value was showed over 8.1㎎/L at each site and COD_Mn, BOD, T-N, T-P tend to increase as they stream down and that the existence and dominance of phytoplankton was low and it was difficult to conclude the definite correlation of water quality and phytoplankton community. Finally, it seemed to be desirable that alternatives for pollutional reduction should be made and performed on the basis of the continuous monitoring of the inflow to preserve the Andong Lake.

Fluoxetine이 Schedule-Induced Polydipsia가 유발된 백서 뇌에서 Tyrosine Hydroxylase 발현에 미치는 영향

이기철,이정호,최영민,정주호,정홍경,이용민,김도형,이대환 大韓神經精神醫學會 2001 신경정신의학 Vol.40 No.2

연구목적: Fluoxetine은 serotonin을 매개하여 간접적으로 dopamine 신경전달기능을 억제한다고 추정되고 있다. 또한 운동장애에서 운동기능의 악화를 유발한다고 알려져 있다. 그러나 신경세포체에서 fluoxetine이 dopamine에 어떠한 영향을 주는지는 아직까지 확실치 않다. 저자들은 schedule-induced polydipsia를 유발시킨 백서 뇌의 흑질, 복부피개영역, 미상핵에서 tyrosine hydroxylase(TH) 발현이 저하됨을 발견하였다. 이를 통해서 fluoxetine이 백서 뇌의 dopamine 기능에 긍정적인지 혹은 부정적인지를 규명하고자 하였다. 방법: 4주간의 schedule-induced polydipsia 과정을 거친 백서에서 면역죄치화학적인 방법으로 흑질, 복부피개영역, 미상핵의 tyrosine hydroxylase 발현이 저하됨을 확인한 후, 실험동물들에게 fluoxetine 10mg/kg를 3주간 복강내 주사하였다. 실험백서들을 희생시켜 뇌 조직을 적출하여, TH 면역조직화학 염색법을 이용하여 흑질, 복부피개영역, 그리고 미상핵의 TH 면역반응세포를 관찰하고 이를 정상백서와 비교하였다. 결과: 1) 다갈증이 유발된 백서의 흑질, 복부피개영역, 미상핵에서 tyrosine hydroxylase 발현이 정상백서 보다 저하됨을 관찰하였다. 2) 3주간에 걸친 fluoxetine 투여후 흑질, 복부피개영역, 미상핵의 tyrosin hydroxylase 발현이 다시 증가하는 소견을 보였다. 결론: Fluoxetine 만성투여가 흑질, 복부피개영역 그리고 미상핵의 tyrosin hydroxylase를 증가시키는 소견을 얻었다. 이러한 결과는 임상에서 dopamine 결핍과 연관된 질환들에서 fluoxetine을 만성투여하면 운동기능을 포함한 증상들의 개선을 가져올 수도 있다고 추정된다. Objective: It has been suggested that fluoxetine inhibits the dopaminergic neurotransmission by serotonergic mediation. And also, it has been shown to inhibit synthesis of DOPA in dopamine-rich areas of the rat forebrain. These dopamine-antagonistic capacity of fluoxetine is only supported by anecdotal report that the increased amount of motor disability in patients with idiopathic Parkinson's disease after exposure to fluoxetine. However, there is still no evidence of the direct effect of fluoxetine on dopaminergic neuronal cell body in the substantia nigra, VTA, caudate & putamen. This study was designed to evaluate the effects of fluoxetine in rat brain which showed decreased numbers of dopaminergic neuronal cell body induced by schedule-induced polydipsia(SIP). Method: We incidentally found that 4 weeks of schedule-induced polydipsic rats revealed the suppression of tyrosine hydroxylase expression in the substantia nigra, VTA, caudate & putamen with the immunohistochemistric measures. After 3 weeks of intraperitoneal injection of 10mg/kg of fluoxetine to the schedule induced polydipsic rats, the tyrosine hydroxylase expression was also measured with immunohistochemistry. We compared the tyrosine hydroxylase expression among the normal control, the polydipsic rats, and the rats with fluoxetine treatment. Results: 1) By contrast with the control, the polydipsic rats revealed the evidence of decreased tyrosine hydroxylase expression in the substantia nigra, VTA, caudate & putamen. 2)After daily injection of fluoxetine for 3 weeks, the polydipsic rats showed increment of tyrosine hydroxyase expression in those areas. Conclusions: In previous studies, a great deal of results suggest that fluoxetine negatively influence the dopaminergic systems indirectly via serotonergic activation such as inhibition of dopamine synthesis or transport system. Although our results are obtained from rodents, we suggest that fluoxetine directly and positively enhance the dopamine system in the substantia nigra, VTA, caudate & putamen. The chronic adminstration of fluoxetine may be helpful to dopamine-depleted condition in clinical situations. We anticipate the replication studies of our findings and well-controlled clinical trial.

에탄올이 백서의 해마에서 Neuropeptide Y 발현에 미치는 영향

정홍경,이기철,이정호,이희제,정주호,이주영 대한생물치료정신의학회 2002 생물치료정신의학 Vol.8 No.1

에탄올을 장기간 섭취한 백서에서 Acamprosate 투여가 Nitric Oxide Synthase 발현에 미치는 영향

정홍경,이기철,이정호,이승휘,이희제,정주호 대한생물치료정신의학회 2002 생물치료정신의학 Vol.8 No.1

한국 정신장애의 역학 조사 연구[I] : 각 정신장애의 유병률

조맹제,함봉진,김장규,박강규,정은기,서동우,김선욱,조성진,이준영,홍진표,최용성,박종익,이동우,이기철,배재남,신정호,정인원,박종한,배안,이충경 大韓神經精神醫學會 2004 신경정신의학 Vol.43 No.4

Objectives : This study aims to estimate the prevalence of the DSM-IV psychiatric disorders in Korean population using the Korean version of Composite International Diagnostic Interview (K-CIDI). Methods : Subjects were selected by taking multi-stage, cluster samples of 7,867 adult household residents, 18 to 64 years of age, in ten catchment areas. Total 78 trained interviewers administered the K-CIDI to the selected respondents, from June 1 to November30,2001. Results : Total 6,275 respondents completed the interview. Some 33.5% of respondents reported at least one lifetime disorder, 20.6% reported at least one-year disorder, and 16.7% reported at least one-month disorder. The most common lifetime disorders were alcohol abuse/dependence (17.24%), nicotine dependence/withdrawal (11.19%), specific phobia (5.16%), and major de-pressive disorder (4.25%). The lifetime prevalence of substance abuse/dependence (0.25%) and schizophrenia (0.16%) was very low. Nicotine and alcohol use disorder showed very high male/female ratio. Mood disorder and anxiety disorder were more prevalent among female than male. Conclusion : The prevalence of psychiatric disorders was high. In comparison with other studies, remarkable differences in distributions of psychiatric disorders across the areas and times were observed.

모형 가스터빈엔진 개발에 관한 연구

이기방,정진은 한국기술교육대학교 2005 論文集 Vol.11 No.1

A model gas turbine engine was designed and developed. The design point was set up through the cycle analysis to design the combustor which is the kernel of an engine. The length, diameter of the combustor and diameter and number etc. of an air inlet hole was designed based on the way suggested by Kunio Suzuki. The designed result is checked by a combustion intensity and a mean residence time if it was designed suitably or not. The design point of the model of the 3kW gas turbine engine was set up in conditions of outlet temperature of the combustor 900K, the rotational speed of the compressor 110,000rpm, the ratio of pressure 1.57, the air flow rate 0.07 kg/s which is supplied into the combustor. The designed specifications of the combustor are as follows : the whole length of the combustor liner 147mm, the diameter 52mm, the diameter of casing 67mm, the hole diameter - the primary zone 5.25mm, the secondary zone 4.64 mm, the dilution zone 7.32mm.

대입 재수생의 면역기능에 대한 연구

이기주,정영조,한기석 大韓神經精神醫學會 1992 신경정신의학 Vol.31 No.1

The authors examined the immune function of 18 college entrance-exam repeater group (experimental group) who are considered to experience psychological stress, comparing with university student group(control group) who are not subjected to such condition. We measured the numbers and ratio of T-cell subsets( including T4 and T8) as well as B-cell and total lymphocyte count in both groups. In comparing the experimental group with the control group, the former showed increased numbers of leukocyte, total lymphocyte, T-lymphocyte and B-lymphocyte. but significant difference was not found in the percentage of B-lymphocyte. T8 percentage, and T4/T8 ratio. But there was decrease in the percentage of T-lymphocyte and T4 in the experimental group. As was shown in the results of the study, we confirmed partially the change of immune function, especially decrease of cell-mediated immunity, which may be the results of psychological stress associated with examination. In our opinion, further studies should focus on the elucidation of whether these findings observed in our research are a direct effect of psychological stress or other attributable variables are involved. Moreover, the clinical implications of change of immune function in this study should be clarified in the subsequent study. For this purpose, qualitative immunologic tests as well as neurondocrinologic tests should be included in the future studies.

관절염 환자의 실태와 관련요인에 대한 분석적 연구

정승기,남철현,신두만,양숙희,김기열,이미경,문기내 대한보건협회 2002 대한보건연구 Vol.28 No.3

This study was conducted to examine the condition of patients with arthritis and its related factors. Data were collected from 100 people who suffered from arthritis in Seoul. Busan, Daegu, Daejun, Junjoo, and pohang from April 2, 2000 to July 31, 2000. The results of this study are summarized as follows : 1. 6L0% of the subjects were female. The incidence rate of arthritis was higher in the higher age group, lower educated group, and thinner group. In case of male, the incidence rate was higher in the groups of single, residents in big cities, and technicians. In case of female, it was higher in the groups of the married, residents in towns or villages, and housewives. 2. According to the parts of arthritis, knee joint covered 67.4% and backspine joint covered 9.0%. The incidence rate of arthritis was higher in the groups of forties, housewives, single, irreligious people, residents in towns and villages, primary school graduates, thin people, and walk exercisers. 3. The arthritis patients felt pain most when they stood up (31.5%). According to the time when they felt pain most, the time when they were active during daytime was 31.5% and nighttime was 29.8%. When they got up in the morning was 22.4%, while 10.9% felt pain all cay long. 4. they had arthralgia knees and cramp in crook of the knees (21.8%). Their knees ticked when they moved (21.1%). The had to rest hands on anyplace when they stood up (18.7%) and they could not completely unfold their knees. 5. The medical institutions which diagnosed them showed significant difference in the variables of sex, age, marital status, religion, place in residence, education level, economic status, obesity level, exercise, parts of arthritis, and posture of feeling pain. from above results, it can be concluded that it is necessary to develop appropriate medical treatment on the basis of the respondents' socio-democraphic characteristics, pain parts, period of having a pain, satisfaction level with treatment and its related factors. Therefore, related professionals and organizations must develop education program for prevention of arthritis in order to educate them.

컨버터로 제어되는 유도전동기 드라이브 시스템의 손실 모델링

정동화,이정철,박기태,이홍균 순천대학교 1999 순천대학교 자연과학논문집 Vol.18 No.2

An accurate loss model of induction motor drive controlled by the converter is proposed. Steady state fundamental and hamonics loss characteristics, besides the dynamics of the machine are analyzed and incorporated in the model, resulting in a new synchronous frame dynamics d-q equivalent circuit. The converter system has been modeled accurately for condition and switching losses.

內燃機關 燃燒室내의 壓力測定에 관한 硏究

鄭性植,李湘石,朴基龍 동아대학교 공과대학 부설 한국자원개발연구소 1990 硏究報告 Vol.14 No.1

In the present study, the influence of the measuring apparatus to the analysis of the combustion is clarified. T재 measuring system used are ; 8-bit system and 12-bit system (composed of 12-bit A/D converter and 16-bit AT grade computer). It was shown that the 12-bit system gave more accurate and more reliable data for the combustion analysis than the 8-bit system.