The population growth and reproduction of Tetrahymena pyriformis were studied under shaken (aerobic) and unshaken (anaerobic) conditions by applying the growth models, exponential and logistic growth models and the population growth of Tetrahymena was showed the logistic growth model under both, shaken and unshaken conditions and also, the more oxygenated samples had greater population size (N) and three times faster growth rate (r) than less oxygenated samples during incubation periods.

본 연구는 유산소운동능력의 차이를 보이는 두 집단이 각각 로윙에르고미터 최대하 운동을 실시한 후 혈중 활성산소의 변화에 어떠한 차이를 나타내는지 구명하는데 목적이 있으며 연구대상으로는 조정 선수집단 6명과 비선수집단 6명을 대상으로 최대유산소운동능력을 검사한 후 각각의 목표심박수 85~90%를 적용하여 로윙에르고미터 운동을 실시하였고 운동 전, 직후, 10분, 20분, 차30분에 각각 채혈하여 활성산소의 변화를 분석하였다. 그 결과는 유산소운동능력의 차이에 따른 활성산소의 변화에서 집단과 시기 간 상호작용 효과는 유의한(p<.05) 차이를 나타내어 시기에 따른 변화의 양상이 집단 간 차이가 있었고 사후검증 결과 회복기 10분에서 20분 그리고 20분에서 30분 구간에서 유의한 차이가 나타났다. 결론적으로 인체에 부정적인 영향을 미치는 활성산소로부터 유산소운동능력이 우수한 조정선수집단이 비선수집단에 비해 긍정적인 회복 패턴을 보였다.

Rice seeds germinate in the complete absence of oxygen. Under anoxia, the seeds have greater stress in abiotic condition than in aerobic one. Antioxidant enzymes play an important role of ROS(Reactive Oxygen Species) scavenging in various anoxic stress. We investigated the relationship between antioxidant enzymes and early seedling growth of four rice cultivars (Iksan 429, Khaiyan, FR13A, and Nampyeong) under anoxic and aerobic conditions. Rice seeds immersed into a sealed water bottle for 10 days. During anoxia, rates of cleoptile elongation were faster in tolerant varietise Iksan 429 and Khaiyan than in FR13A and Nampyeong. In the anoxic water condition, the activity of SOD in Iksan 429 and Khaiyan increased slightly until 5 days , while that of Nampyeong and FR13A decreased significantly after 7 days. The activity of peroxidase in Khaiyan was higher than that of FR13A. These results suggest that the ability to increase SOD and POX may be one of the determinants in anoxia tolerance of rice.

Dinitrophenol is preventing cells from making energy for growth and it has been suggested that pH may be important in mitigating effects of uncouplers. The effect of pH on toxicity of dinitrophenol at high concentration was investigated, over a pH range of 5.7 to 8.7. DNP inhibition was found to be strongly dependent on mixed liquor pH. The DNP degradation rate was highest in the pH range of 7.0 to 7.8; at pH 6.0 degradation of 0.41 mM dinitrophenol was significantly inhibited; at pH <5.7, dinitrophenol degradation was completely inhibited after approximately 25% of the dinitrophenol was degraded. However no significant effect of pH variation was seen on glucose uptake by the activated sludge mixed culture.

운동심리학(exercise psychology) 문헌들은 운동이 수면을 향상시키는 효과가 있다고 밝혀왔다. 이 연구의 목적은 일회성 유산소운동 강도에 따라 성인남자의 수면질(sleep quality)과 정서에 어떤 변화가 일어나는 지를 알아보는 것이었다. 연구 참여에 동의한 15명의 대학교 기숙사 남학생들은 균형배정(counter-balance)을 원칙으로 각 강도의 운동(60%, 80%, 최대강도)을 차례로 수행하였다. 피험자들은 운동을 수행한 날 저녁 취침 직전에 체온을 측정하고 잠자리에 든 시간을 기록한 후 수면을 시작하였으며, 다음 날 기상과 함께 수면질 검사지와 정서상태 검사지를 완성하였다. 조건간의 평균을 비교하기 위해 실시한 반복측정 일원변량분석(one-way ANOVA repeated measure) 사후검정(LSD) 결과 수면질은 80%강도의 운동 후가 비운동(no exercise) 후보다 높았고(p<.01), 잠드는데 걸린 시간도 80%의 운동이 비 운동에 비해 짧았으며(p<.05), 총수면시간은 60%의 운동 후가 비운동에 비해 긴 것으로(p<.05) 나타났다. 정서에서는 활력이 80%의 운동에서 비운동과 비교하여 높은 변화를 보였고(p<.05), 혼동과 총정서장애는 60%와 80% 강도의 운동 후에 비운동 후보다 낮아졌다(p<.05). 수면 전 체온은 최대운동과 비운동 사이에서만 유의한 차이가 나타났다(p<.05). 이 연구는 남자 성인들의 수면질을 향상시키기 위한 운동은 최대운동능력의 80% 강도가 적당하고, 수면 후 긍정적 정서를 위해서는 60% 강도의 운동도 권장될 수 있다는 결론에 도달하였다. 그 외 연구결과를 토대로 후속 연구들을 위한 방향이 논의되었다.

From sludge of S municipal wastewater treatment plant in Busan, Korea, we isolated the denitrifier DN-9 which showed the ability of denitrification under aerobic condition by the color change and gas formation in liquid culture with Giltay medium. The isolated strain was identified as Pseudomonas sp. DN-9 on the basis of the morphological, physiological, biochemical and nucleotide sequence analysis of 16S rRNA. The isolated strain, Pseudomonas sp. DN-9, has cytochrome cd1 nirS of nitrite reductase. By the co-existance of additional ammonium and nitrate ion, the strain was not affected largely on growth in SL series broth. It seemed the result of denitrification. Although Pseudomonas sp. DN-9 has a good nitrate reduction activity under aerobic condition, the activity is less than Pseudomonas stutzeri in same cultivation condition. However, Escherichia coli had little the activity of aerobic denitrification and Pseudomonas putida showed lower activity of aerobic denitrification than Pseudomonas sp. DN-9 and Pseudomonas stutzeri in this study.

The research was performed to compare to the biofilm characteristics and phenol removal efficiency in RBCs(Rotating Biological Contactor) using Rhodococcus sp. EL-GT(single population) and activated sludge(mixed population) as inoculum. Both reactors showed similar tendency on variations of dry weight, thickness and dry density of biofilm. However, the growth of biofilm thickness in 3 and 4 stage of single population reactor has sustained longer than that of the mixed population reactor. Unlike the mixed population reactor, the dry density of biofilm in the single population reactor had a difference between 1, 2 stage and 3, 4 stage. The single population reactor was stably operated without the decrease of phenol removal efficiency in the range of pH 6～9 and 15mM phenol was completely degraded in these pH ranges. But in case of the mixed population reactor, the phenol degradability was dramatically decreased at over 5mM phenol concentration because of the overgrowth and detachment of its biofilm.

Wastewater from the pigment industry has high levels of organics and is known as hardly biodegradable. The objective of this study is to evaluate the applicability of aerobic fixed-bed biofilm reactor packed with ceramic support carrier for the pigment wastewater treatment. Orange 2(widely used azo pigment) adsorption experiment onto biofilm and activated sludge, and continuous treatment experiments were performed. In batch adsorption experiment, maximum adsorption quantity of biofilm was at least two times higher than that of activated sludge. In continuous experiment using aerobic fixed-bed biofilm reactor, the influent concentration of COD and Orange 2 were 75∼500㎎/ℓ(0.45∼3.00㎏ COD/㎥.day), 5∼50㎎/ℓ (0.03-0.30㎏ Orange 2/㎥.day), respectively. At a COD loading rate of 2.5㎏ COD/㎥.day and Orange 2 loading rate of 0.18㎏ Orange 2/㎥.day, removal efficiency of COD and Orange 2 were over 95%, 97%, respectively.

This research was performed to investigate the dynamics of microbial community by RBC (Rotating Biological Contactor) using Rhodococcus sp. EL-GT and activated sludge. Cell counts revealed by DAPI were compared with culturable bacterial counts from nutrient agar. Colony counts on nutrient agar gave values 20∼25% and 1∼15% of cell counts (DAPI). The cell counts for the dynamics of bacterial community were determined by combination of in situ hybridization with fluorescently-labelled oligonucleotide probes and epifluorescence microscopy. Around 90∼80% of total cells visualized by DAPI were also detected by the bacteria probe EUB 338. For both reactors proteobacteria belonging to the gamma subclass were dominant in the first stage (1 and 2 stage) and proteobacteria belonging to the gamma subclass were dominant in the last stage (3 and 4 stage).

Several microorganisms which degrade phenol and trichloroethylene (TCE) were isolated from the activated sludge of a wastewater treatment plant. Among them, one isolate EL-04J showed the highest degradability and was identified as a Pseudomonas species according to morphological, cultural and biochemical properties. The phenol-induced cells of Pseudomonas EL-04J, which were preincubated in the mineral salts medium containing phenol as a sole carbon source, degraded 90% of 25μM TCE within 20 h. This strain could also utilize some of methylated phenol derivatives (o-cresol, m-cresol and p-cresol) as the sole source of carbon and energy. Cresol-induced cells of Pseudomonas EL-04J also cometabolized TCE.

This study was conducted to evaluate capability of dyeing wastewater treatment for 3 type reactors. These reactors were Packed Bed Reactor(PBR), Fluidized Bed reactor(FBR) and Moving Media Complete Mixing Activated Sludge reactor(MMCMAS). Experiments of PBR and FBR were performed by various packing ratios and organic loading rates, experiments of MMCMAS were performed by various organic loading rates In order to obtain SBOD_5 removal efficiencies of more than 90%, the F/Mv ratios of PBR, FBR, MMCMAS were 0.11 ㎏BOD/㎏MLVSS·d, 0.12 ㎏BOD/㎏MLVSS·d, and 0.37 ㎏BOD/㎏MLVSS·d, respectively. So MMCMAS system which has more active microorganisms showed better capability of organic removal and also stronger dynamic and shock loadings than those of PBR and FBR. In PBR and FBR, the media packing ratio of 20% showed better performance of organic matters removal effciencies than 10% and 30%, but sludge production rate at media packing ratio of 30% was relatively lower than that of 10% and 20%. When more than 90% organic matters removal efficiency was obtained, the ratios of attached biomass to total biomass at PBR, FBR, MMCMAS were 89∼99%, 87∼98%, and 54∼80%, respectvely. The ratio of attached biomass to total biomass was low in MMCMAS. This was formation of thin biofilm due to shear force between rotating disc and water. The average sludge production rates(㎏VSS/㎏BODrem.) of PBR, FBR and MMCMAS were 0.20, 0.29 and 0.54, respectively.

This study aims to observe the inhibition of methane generation, the decomposition of organic matter, and the trend of outflowing leachate, using the simulated column of the anaerobic sanitary landfill structure of sulfate addition type which is made by adding sulfate to a current anaerobic landfill structure, and the simulated column of semi-aerobic landfill structure in the laboratory which is used in the country like Japan in order to inhibit methane from a landfill site among the gases caused by a global warming these days, and at the same time to promote the decomposition of organic matter, the index of stabilization of landfill site. As a result of this study, it is thought that the ORP(Oxidation Reduction Potential) of the column of semi-aerobic landfill structure gradually represents a weak aerobic condition as time goes by, and that the inside of landfill site is likely to by in progress into anaerobic condition, unless air effectively comes into a semi-aerobic landfill structure in reality as time goes by. In addition, it can be seen that the decomposition of organic matter is promoted according to sulfate reduction in case of R1, a sulfate-added anaerobic sanitary landfill structure, and that the stable decomposition of organic matter in R1 makes a faster progress than R2. Moreover it can be estimated that R1, a sulfate-added anaerobic sanitary landfill structure has an inhibition efficiency of 55% or so, compared with R2, a semi-aerobic landfill structure, in the efficiency of inhibiting methane.