• Title/Summary/Keyword: Biological systems

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Evaluation of Biological Organic and Nutrient Removal Performance in Intermittent MBR Systems by Computer Simulation (컴퓨터 시뮬레이션을 이용한 간헐폭기 MBR시스템에서의 유기물 및 영양염류 처리 성능 평가)

  • Yoo, Hosik;Rhee, Seung-Whee
    • Journal of the Korea Organic Resources Recycling Association
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    • v.21 no.3
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    • pp.82-92
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    • 2013
  • The Intermittent Aeration MBR systems have the advantage of controlling reaction time by changing aeration period and are one of economic BNR systems since these processes do not require MLSS recirculation that demands capital and operation costs. In this study, two intermittent aeration MBR systems were studied by computer simulation: an intermittent aeration MBR system that had both 1hr/1hr and 4hr/4hr aeration/unaeration periods at intermittent reactor and NEW INTERMITTENT-process that was an energy saving process and certified as a new process by Korean government. Since DO concentration reached only at 0.23mg/L at intermittent reactor when it was aerated, the Intermittent aeration MBR system having 1hr/1hr aeration/unaeration period showed simultaneous nitrification/denitrification and had the highest nitrogen and phosphorus removal efficiencies that were 57% and 55%, respectively. Since this study was based on the constant influent flow and characteristics, more studies are needed to define the operational characteristics of intermittent aeration MBR systems under dynamic influent conditions.

Alcohol Impairs learning of T-maze Task but Not Active Avoidance Task in Zebrafish

  • Yang, Sunggu;Kim, Wansik;Choi, Byung-Hee;Koh, Hae-Young;Lee, Chang-Joong
    • Animal cells and systems
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    • v.7 no.4
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    • pp.303-307
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    • 2003
  • The aim of this study is to investigate whether alcohol alters learning and memory processes pertaining to emotional and spatial factors using the active avoidance and T-maze task in zebrafish. In the active avoidance task, zebrafish were trained to escape from one compartment to another to avoid electric shocks (unconditioned stimulus) following a conditioned light signal. Acquisition of active avoidance task appeared to be normal in zebrafish that were treated with 1% alcohol for 30 min for 17 days until the end of the behavioral test, and retention ability of learned behavior, tested 2 days later, was the same as control group. In the T-maze task, the time to find a reservoir was compared. While the latency was similar during the 1 st training session between control and alcohol-treated zebrafish, it was significantly longer in alcohol-treated zebrafish during retention test 24 h later. Furthermore, when alcohol was treated 30 min after 2nd session without prior treatment, zebrafish demonstrated similar retention ability compared to control. These results suggest that chronic alcohol treatment alters spatial learning of zebrafish, but not emotional learning.

Radish phospholipid hydroperoxide glutathione peroxidase provides protection against hydroperoxide-mediated injury in mouse 3T3 fibroblasts

  • Li, Tian;Liu, Guan-Lan;Duan, Ming-Xing;Liu, Jin-Yuan
    • BMB Reports
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    • v.42 no.10
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    • pp.648-654
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    • 2009
  • Overexpression of phospholipid hydroperoxide glutathione peroxidase (PHGPx) genes has been reported to play an important role in protecting host cells from oxidative injury in several model systems. A radish phospholipid hydroperoxide glutathione peroxidase (RsPHGPx) known to have high catalytic activity was applied to mouse 3T3 fibroblasts to determine the protective effects of PHGPx against oxidative injury triggered by hydroperoxides such as hydrogen peroxide ($H_2O_2$), tert-butyl hydroperoxide (t-BHP) and phosphatidylcholine hydroperoxide (PCOOH). We observed that preincubation of cells with RsPHGPx significantly increased cell viability, reduced levels of malondialdehyde (MDA), inhibited generation of reactive oxygen species (ROS), and maintained natural cell shapes after treatment with $H_2O_2$, t-BHP or PCOOH, indicating that the exogenous RsPHGPx can act as an effective hydroperoxide-scavenger and may also protect target cells from oxidative damage. These results suggest the possibility for use of RsPHGPx as a therapeutic protectant.

Regulation of Ethylene Emission in Tomato (Lycopersicon esculentum Mill.) and Red Pepper (Capsicum annuum L.) Inoculated with ACC Deaminase Producing Methylobacterium spp.

  • Yim, Woo-Jong;Woo, Sung-Man;Kim, Ki-Yoon;Sa, Tong-Min
    • Korean Journal of Soil Science and Fertilizer
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    • v.45 no.1
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    • pp.37-42
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    • 2012
  • Improvement of plant growth by Methylotrophic bacteria can be influenced through alterations in growth modulating enzymes or hormones, especially by decreasing ethylene levels enzymatically by 1-aminocyclopropane-1-carboxylate (ACC) deaminase or by production of indole-3-acetic acid (IAA). In this study, the effect of seven strains of Methylobacterium on seedling ethylene emission of tomato and red pepper plants was evaluated under greenhouse condition. Ethylene emission was lowest in Methylobacterium oryzae CBMB20 inoculated tomato plants and CBMB110 inoculated red pepper plants at 47 days after sowing (DAS). However, at 58 DAS all inoculated plants showed almost similar pattern of ethylene emission. Methylobacterium inoculated tomato and red pepper plants showed significantly less ethylene emission compared to control. Our results demonstrated that Methylobacterium spp. inoculation promotes plant growth due to the reduction of ethylene emission and therefore can be potentially used in sustainable agriculture production systems.

Reductive Dechlorination of Polychlorinated Biphenyls as Affected by Natural Halogenated Aromatic Compounds

  • Kim Jongseol;Lee Ahmi;Moon Yong-Suk;So Jae-Seong;Koh Sung-Cheol
    • Journal of Microbiology
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    • v.44 no.1
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    • pp.23-28
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    • 2006
  • We investigated the effects of halogenated aromatic compounds (HACs) including naturally occurring ones (L-thyroxine, 3-chloro-L-tyrosine, 5-chloroindole, 2-chlorophenol, 4-chlorophenol and chlorobenzene) on polychlorinated biphenyl (PCB) dechlorination in sediment cultures. A PCB-dechlorinating enrichment culture of sediment microorganisms from the St. Lawrence River was used as an initial inoculum. When the culture was inoculated into Aroclor 1248 sediments amended with each of the six HACs, the extent of dechlorination was not enhanced by amendment with HACs. The dechlorination patterns in the HAC-amended sediments were nearly identical to that of the HAC-free sediments except the 3-chloro-L-tyrosine-amended ones where no dechlorination activity was observed. When these sediment cultures were transferred into fresh sediments with the same HACs, the dechlorination specificities remained the same as those of the initial inoculations. Thus, in the present study, the substrate range of the highly selected enrichment culture could not be broadened by the HACs. It appears that HACs affect PCB dechlorination mainly through population selection rather than enzyme induction of single population.

Molecular Taxonomical Re-classification of the Genus Suillus Micheli ex S. F. Gray in South Korea

  • Min, Young Ju;Park, Myung Soo;Fong, Jonathan J.;Seok, Soon Ja;Han, Sang-Kuk;Lim, Young Woon
    • Mycobiology
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    • v.42 no.3
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    • pp.221-228
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    • 2014
  • The fungal genus Suillus Micheli ex S. F. Gray plays important roles in the survival and growth of plant seedlings. Humans have utilized these ectomycorrhizal fungi to enhance the nutrient uptake and defense systems of plants, particularly in the reforestation of coniferous forests. The genus Suillus is easily distinguishable by its distinctive morphological features, although the morphology of the fruiting body does not facilitate reliable interspecies discrimination. On the basis of micro-morphological features and internal transcribed spacer sequence analysis, we found that 51 of 117 Korean Suillus specimens had initially been misidentified. The list of the 12 Suillus species previously recorded in Korea was re-evaluated and revised to only eight distinct species: S. americanus, S. bovinus, S. granulatus, S. grevillei, S. luteus, S. pictus, S. placidus, and S. viscidus. We provide taxonomical descriptions for six of these species from the sample specimens.

Self-care, Social Support, and Biological Markers in Liver Transplant Recipients (간이식 수혜자의 자가간호이행, 사회적 지지, 생리학적 지표)

  • Kim, Hyunkyung;Choi, Mona;Kim, So Sun;Kim, Soon-Il
    • Korean Journal of Adult Nursing
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    • v.27 no.2
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    • pp.170-179
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    • 2015
  • Purpose: To examine the relationships between self-care, social support, and biological markers in liver transplant recipients. Methods: The participants included 118 liver transplant recipients who visited outpatient clinic at Y University Hospital in Seoul from April to May, 2013. Questionnaires consisted of self-care and social support scales. The biological markers were collected by reviewing electronic medical records. Data were analyzed with descriptive statistics, t-test, ANOVA with Scheff$\acute{e}$ post-hoc test, and Pearson's correlation. Results: The self-care score was significantly higher in a patient group within 6 months post-transplant when compared to a patient group post-transplant 3 to 5 years (F=3.10, p=.018). The self-care showed positive correlation with social support with statistical significance (r=.36, p<.001). Conclusion: As the self-care in liver transplant recipients had a positive correlation with social support from family and healthcare providers, the development of comprehensive long-term nursing intervention systems including counseling, education, and support in consideration of progress of time period after transplantation is necessary to enhance self-care behaviors among this population.

The Effect of Idesolide on Hippocampus-dependent Recognition Memory

  • Lee, Hye-Ryeon;Choi, Jun-Hyeok;Lee, Nuribalhae;Kim, Seung-Hyun;Kim, Young-Choong;Kaang, Bong-Kiun
    • Animal cells and systems
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    • v.12 no.1
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    • pp.11-14
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    • 2008
  • Finding a way to strengthen human cognitive functions, such as learning and memory, has been of great concern since the moment people realized that these functions can be affected and even altered by certain chemicals. Since then, plenty of endeavors have been made to look for safe ways of improving cognitive performances without adverse side-effects. Unfortunately, most of these efforts have turned out to be unsuccessful until now. In this study, we examine the effect of a natural compound, idesolide, on hippocampus-dependent recognition memory. We demonstrate that idesolide is effective in the enhancement of recognition memory, as measured by a novel object recognition task. Thus, idesolide might serve as a novel therapeutic medication for the treatment of memoryrelated brain anomalies such as mild cognitive impairment(MCI) and Alzheimer's disease.

A Wrapper Model for Integrated Access to Biological Information Sources (생물 정보원에 대한 통합 접근을 위한 랩퍼 모델)

  • Park, Eun-Koung;Kang, Dong-Wan;Jung, Chai-Young;Bae, Jong-Min
    • The KIPS Transactions:PartD
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    • v.11D no.4
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    • pp.765-774
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    • 2004
  • In order to integrate heterogeneous biological information sources, it is necessary to define the view that represents unified viewpoint for the multiple sources by hiding heterogeneity of the data. We present an XML-based view definition model and show Its operating principles in designing the middleware system to integrate biological information sources. This model supports the user-defined XML view to increase flexibility in constructing the integration system and execute integrated queries on higher level ion. Based on the view-definition model, we present a wrapping model for relational database systems and web resources as well as an application program.

Applicability of the lenten's Reagent Oxidation to Biological Fixed-Film Process for Reuse of Effluents from the Petrochemical Wastewster Effluent Treatment Plant (석유화학폐수 처리장 방류수의 재이용을 위한 고정생물막 공정에서 Fenton 산화전처리의 적응가능성)

  • Lee, Kyu-Hoon;Kim, Mi-Hwa;Park, Tae-Joo
    • Journal of Environmental Science International
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    • v.4 no.5
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    • pp.115-115
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    • 1995
  • Reuse of industrial effluents through the cooling systems in a petrochemical complex was described. The partial oxidation of the effluents from the biological treatment plant was examined, using Fenton''s reagent as a pretreatment step prior to a next treatment of the effluents. Next tertiary treatment using fixed-film reactor resulted in marked reductions in COD and suspended solids. The continuous fixed-film process with Fenton oxidation pretreatment showed a 23% increase in the COD removal efficiency when compared to that without pretreatment of Fenton oxidation under the volumetric organic loading rate of 0.1 kg COD/m3/day. The Fenton oxidation treatment seemed to be a possible method for tertiary biological treatment to reduce the residual toxicity with the enhanced biodegradation of the effluents.