Anabaena variabilis ATCC 29413의 生長과 窒素固定活性에 미치는 環境要因의 影響

宋承達,韓東勳 慶北大學校 1992 論文集 Vol.52 No.-

Anabaena variabilis ATCC 29413, a photoautotrophic and nitrogen fixing cyanobacteria, was in vestigated on the growth, heterocyst differentiation and nitrogen fixation activities(ARA) along different media and environmental treatments. The lag phase in the growth curve with N-added Allen & Arnon(AA/8) was shorter than those with N-free AA/8 and N-added BG 11 media. The nitrogen fixation activity increased for 144hours during initial cell growth (Abs_660 =0.8) with N-free medium of AA/8 and then decreased, while the growth continued. It was assumed that the drastic decline of ARA beyond the cell growth of A_660=0.8 was caused by the accumulation of nitrate(NO_3^- -N ; 4.2ppm)in the medium. The accumulation of ammonium(NH_4+ -N) in the medium was about 0.32 ppm after 156hours of cell growth. The optimal conditions for nitrogenase activity of A. variabilis ATCC 29413 were anaerobic, 10,000 lux, 30℃ and pH 8 with the N-free minimal medium. The activity was significantly inhibited by less concentrations of ammonium(1 mM) than that of nitrate(6 mM). Phosphate and carbonate inhibited the activity by high concentrations although low concentrations stimulated the activity. The treatments of several toxic heavy metals showed strong inhibition of the nitrogenase activity in the order of Hg^++>Cd^++>Co^++>Zn^++>PB^++, and the concentrations for 50% inhibition of the maximum ARA were 0.41, 0.47, 0.51, 0.66 and 8.1ppm, respectively. The recovery of ARA and growth by the carbon sources in the dark condition was observed in the low concentration(1%) and in the order of sucrose>fructose>flucose.

인천교육대학교 과학ㆍ수학 영재 캠프의 운영에 관한 기초 연구

송상헌,정동권,강호감,여상인,노석구 인천교육대학교 과학교육연구소 2003 과학교육논총 Vol.15 No.-

경기도와 인천시의 초등교사 양성을 책임지고 있는 인천교육대학교의 입장에서는 경기·인천지역의 초등 과학과 수학분야의 영재교육 프로그램을 경험하려는 학생들에게 기대와 요구를 충족시켜 줄 책임과 의무가 있다. 이에 인천교육대학교에서는 과학교육연구소가 중심이 되어 영재교육연구원이나 영재교육원을 설치하기 위한 장기적인 목표 하에 과학·수학 영재교육을 실시할 수 있는 실제적인 방안을 모색할 필요성에 따라, 우선 실험적으로 캠프 형식의 운영을 실험해 보았다. 본 연구는 이러한 구체적인 현장 사례연구를 바탕으로 인천교육대학교에서 주관하는 영재교육추진 기본 계획 수립을 위한 초등 과학·수학분야 영재교육 프로그램의 운영 모델과 그것의 실천에 필요한 장기적인 전망을 제안한다. 캠프에서 운영할 수 있는 프로그램의 성격은 심화형의 다 주제 탐구형으로 진행하면서 다양한 교과나 체험을 위주로 한 내용과 형식을 갖출 것을 권장한다. 영재캠프에 참가할 수 있는 자격 조건과 선발 기준은 운영하고자 하는 프로그램의 내용과 성격에 가장 부합하도록 특성화되어야 하고, 캠프에 참가한 학생들에 대한 지속적인 사후 관리가 필요하다. 지속적인 교육과 운영을 위해서는 장기적인 연구 계획 및 예산 수립이 필요하며, 각 교과의 전문가들과 보다 장기적인 공동연구를 수행해야만 한다. 그러면서 영재교육연구원이나 영재교육원의 운영을 목표로 영재교사 양성을 위한 직무연수 프로그램이나 부설 사회교육원의 프로그램을 통해 학부모 교실을 운영할 수 있음도 제안한다. This is a basic study on the science and math camp program for the gifted and talented children in science and mathematics. We organized and managed empirical camp twice for 2 years. From those experiences, we proposed a sample model to manage good camp and a long term vision. This is the result of the basic study on the management of the science and mathematics camp program in Inchon National University of Education.

에너지 트랩 單一 電極 세라믹 필터의 주파수 스펙트럼

宋埈泰,鄭仁永,李鍾德,徐東勳 成均館大學校 科學技術硏究所 1991 論文集 Vol.42 No.1

The thickness -extensional trapped energy mode vibrations are treated analytically. In each program the solution cinsists of a sum the dominant plate eigensolutions for shoted electrodes in the electroded resgion and for zero surface charge in the unelectroded region. The driven thickness solution is also included in the electroded region in the programs of forced vibrations. Combinations of these solutions for the infinite plate, which satisfy the differance equations and boundary conditions on the major surfaces exactry, are then employed in an appropriate variational principle of the linear piezoelectricity in order to satisfy the remaining boundary conditions at the junction between the electroded and unelectroded regions approximately.

9.5/65/35 PLZT를 이용한 Color filtering 특성에 관한 연구

宋埈泰,余東勳,李範熙 成均館大學校 科學技術硏究所 1992 論文集 Vol.43 No.1

In this study 9.5/65/35 PLZT was selected which has the excellent quadratic electro-optic property and slim-loop. It was fabricated by the methods of vacuum hot-pressing and sintering. The electrode of color filter was evaporated using the interdigital type masks. They had the ratio of electrode gaps and the specimen thickness which were 1 : 1, 1.5 : 1, 2 : 1, and 2.5 : 1. Its color filtering characteristics were measured in the range of wavelength 380 to 780[nm] and electric field 0 to 15[kV/cm]. The results shows the relationship between the thickness of specimen, the electrode gap and the maximum RGB transmittance.

농촌지역 노인들의 우울증상에 관련된 요인들의 특성

송미숙,전기홍,송현종,김정은,박승구,신상건,이동훈,정성현,최연주,최완철,최민규,황재철,홍지만 아주대학교 1997 아주의학 Vol.2 No.2

This study was performed to identify risk factors for depression among the elderly in a rural area. A survey was done for the elderly living in Gosam-myenn, Ansung-kun during the period of July 28, 1997 and July 30, 1997. Demographic and sodoeconornic characteristics, and functional and health Status were assessed using a structured questionnaire, and the level of depression was measured by GDS score. The data obtained were analyzed by frequencies, percentage, t-test, ANOVA, and multiple regression, and the results were as follows: 1. The total sample consisted of 133 elderly. Of them, 47 elderly (35.4%) showed significant depressive Symptoms. 2. The GDS score was the highest for the group over 85 years of age (p < 0.05). Those living alone or widowed showed lower GDS score than those living with someone or married (p < 0.05). 3. The GDS score was the highest in the absolutely dependent group, followed by the partially dependent group, and the independent group (p < 0.01). The elderly who perceived their health Status as excellent showed the lowest GDS score. In contrast, those who had more than five chronic diseases showed the highest GDS score. 4. The elderly receiving financial and emotional support from their family or friends showed lower GDS score compared to those without any support. 5. The economically dependent group showed higher GDS score than that of independent group. 6. The elderly who involved in leisure activities showed lower GDS score than those without any involvement. 7. In terms of risk factors for depression, we found that perceived health Status, subjective economic Status, leisure activities, living arrangement and financial support were inversely associated with GDS score, whereas labor support was positively associated with GDS score. Based upon the above findings, this study suggests that these risk factors for depression in the elderly should be taken into consideration for a comprehensive mental health program for the elderly living in the rural area.

신장내 국소혈류량 조절에 대한 신교감신경의 영향

양훈모,민영기,김동진,송호연,송윤섭 순천향의학연구소 2001 Journal of Soonchunhyang Medical Science Vol.7 No.2

Control of blood pressure is affected by regulation of intrarenal blood flow. Renal sympathetic nerve simulation inhibits pressure-depressor mechanism of kidney. This antidepressor mechanism was known as happening to due to a decrease the blood supply of renal medulla. It is not known whether renal sympathetic nerve innervation of renal medulla is and it affects regulation of medullary blood flow. We tried to measure total renal blood flow(TRBF), cortical blood flow(CBF), papillary blood flow(PBF) by ultrasonic and laser Doppler techniques in Wistar rats during 3 kinds of renal sympathetic nerves stimulation. The simulation orders are tried randomly and each stimulation period is 15 minute. TRBF and CBF decreased at 1 Hz by 2 and 2%, 3Hz by 18 and 15%, 5Hz by 49 and 44%, respectively as similar to each other. But PBF increased by 1% at 1 Hz and 4% at 3 Hz, while it decreased by 4% at 5 Hz. Therefore, it seems superficial renocortical and total renal blood flows are closely regulated by renal sympathetic nerves with increasing vasoconstriction at 5 Hz, onthe other hand while medullary blood flow seems to be under strong local control, tending to offset neurogenic flows restrictions.

사업장 소음 폭로에 의한 일과성 역치 상승과 회복

조수헌,하미나,한상환,주영수,성주헌,강종원,윤덕로,송동빈,이명학,김선태 大韓産業醫學會 1996 대한직업환경의학회지 Vol.8 No.2

To determine the recovery time from noise-induced temporary threshold shift(TTS), a prospective field study was conducted at three worksites where workers are known to be exposed high level of noise. Subjects were selected according to answers on a questionnaire which inquired about otological history and previous noise exposure, including avocational, military and occupational exposures. After excluding employee with past otologic problems, recent exposure to high level noise, and under medications, total 92 employees participated in the study. Among 92 participants, complete consecutive audiometric examinations were carried out at 0∼2 hours, 5∼7 hours, 14∼16 hours after worktime noise exposure on 26 participants wearing hearing protectors and 22 participants wearing no protective devices. The difference between the hearing level 0∼2 hours after noise exposure and 5∼7 hours is statistically significant by paired t-test(p<0.01). The median recovery times calculated from the data of 22 participants wearing no protective hearing devices are 15.6 hours at 4000Hz, and 7.7 hours, 10.3 hours, 8.4 hours at 1000Hz, 2000Hz and 8000Hz respectively. These data suggest that when measuring the pure tone audiometry for noise exposed workers, at least 16 hours noise-free interval is required.

Cluster analysis 에 의한 昭陽湖의 水體 分布

조규송,안태석,김범철,이동훈 江原大學校 附設 環境硏究所 1989 環境硏究 Vol.6 No.-

Cluster analysis was applied for the distinction of the water body in Soyang lake, which is the largest lake in Korea. For this analysis, the sixteen environmental parameters, such as water temperature, nutirent salts, organic materials, ets were used as the input data. The total data matrix was 16parameters X 47 points (in 14 sites). After Standardization, the Euclidean distances between two points were calculate. By the results, main stream of Soyang lake can be classified with 5 groups in March, 10 groups in February. And two shallow tributaries, showed different grouping pattern from main stream. In March, and November, the vertical mixing was detected, and in August, the water body above 10m was showed complex grouping pattern, and showed two water bodies in middle layer, and one in bottom layer.

소양호에서의 종속영양세균의 종구성 및 Alkaline phosphatase 분비 세균에 관한 연구

이동훈,안태석,조규송 江原大學校 附設 環境硏究所 1990 環境硏究 Vol.7 No.-

The total and heterotrophic bacterial distributions, compositions and alkaline pho-sphatese activities were analyzed in Lake Soyang from Sep. 1987 to Aug. 1988. The heterotrophic bacteria was small porition, 0.07-2.63% of total bacterial number which ranged from 3.2×10^(5) to 3.2×10^(6) cells/ml. The composition of bacterial commumity was less diverse insummer and at the fish farm site and Pe-ridinium blooming site. Pseudomonas and Flavo bacterium were the dominant genera in all sites. The highest proportion and activity of alkaline phsophatase was appeared in Flavobacterium, while Pseudomonas was the most predominant group.

Pseudorabies Virus의 Major Capsid Protein 유전자의 클론닝과 Baculovirus Vector System에 의한 발현

안동준,전무형,송재영,박종현,현방훈,장경수,안수환 충남대학교 생물공학연구소 1997 생물공학연구지 Vol.5 No.-

Pseudorabies is caused by Pseudorabies virus (PRV: Aujeszky's disease virus) of Herpesviridae that is characterized by 100 to 150nm in size with a linear double-stranded DNA molecule with of approximately 90 × 10 exp (6)Da. This disease affects most of domestic animals such as swine, cattle, dog, sheep, cat, chicken, etc. causing high mortality and economic losses. In swine, young piglets show high mortality and pregnant sows, reproductive failures. However the adult swine reveals no clinical signs in general. But they become a carrier state and play an importnat role for propagation of the disease. In this study, the nucleotide sequence of major casid protein gene of PRV, Yangsan strain isolated from the diseased swine in Korea was analyzed, and the recombinant MCP was produced by expression of the MCP gene in Sf-9 cell using baculovirus transfer vector system. As result, in BamHI digestion, MCP gene locus of PRV YS strain showed different from that of Indiana S strain. The patterns of enzyme mapping were also found to be unidentical each other. The sequence of the MCP gene partially analyzed showed 98.09% identity to Indiana S strain. The expression of MCP in Sf-9 cell cotransfected by pVLMCP-44 baculovirus expression vector was characterized by Southern blot hybridization, immunofluoresent and immunocytochemical tests, SDS-PAGE and Western blotting. The rMCP with M.W. 142kDa was most effectively expressed in Sf-9 cells at the 3-4th days post inoculation of the recombinant baculovirus by 2 moi.