• 미생물학회지
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• 제32권1호
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• pp.7-11
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• 1994

미산소성 세균으로 알려진 질소고정균 Arcobacter nitrofigilis는 brucella 액체배지에서 호기적 생장의 특성을 나타내었다. 일반대기의 산소조건(21% $O_2$)하에서 최대생장의 특성을 보여주었다. 2% 이하의 산소조건하에서 산소 이외의 다른 최종산소수용체를 첨가하지 않은 액체배지에서 이 세균은 적은 정도의 생장을 나타내었다. 이 세균은 전자전달계 구성성분인 세포막에 함유되어 있는 cytochrome b 및 c, 그리고 용해성 cytochrome c를 가지고 있었다. 일반대기의 산소조건에서의 최대생장, 낮은 산소 농도하에서의 적은 정도의 생장 및 cytochrome c의 존재로 볼 때 이 세균은 미산소성 세균이나 통성혐기성 세균이 아니고, 호기성 세균임을 나타내주며, 또한 이 세균은 산소를 이용한 호픕에 의해 에너지를 얻음을 나타내준다.

• 한국지역사회생활과학회지
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• 제21권1호
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• pp.71-79
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• 2010

This study was conducted to develop fresh-cut and processed pears. After treatment of citric acid (1%) or N-acetylcysteine (0.2 M), and co-treatment of citric acid (1%) and N-acetylcysteine (0.2 M) into the pears c.v. 'Wonhwang', the quality changes of pears during cold storage ($1^{\circ}C$) for 10 days were investigated respectively. Pear quality and the taste of pears increased much more in those treated with anti-browning agents than those in the control group at 10 days after anti-browning treatment and cold storage. Changes in Hunter b values of pears treated with 0.2 M N-acetylcysteine were insignificant. Those with Polyphenol oxidase (PPO) activity and ethylene production were had the most decreased effects and those with the phenolics compound contents were the most lowered. Firmness of fruits increased in treatment of 0.2 M N-acetylcysteine + 1% citric acid solution. The amount of respiration decreased in the application of 1% citric acid solution. Consequently, fruit freshness can be maintained more effectively by the treatment of the anti-browning agent compared to non-treatment, even if the effectiveness were different among different kinds of anti-browning agents.

• Biomolecules & Therapeutics
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• 제9권3호
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• pp.224-230
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• 2001

DKY is an oriental drug preparation composed of 17 natural products and is known to have antihyperglycemic action at 100 mg/kg po in animal tests. The general pharmacological properties of DKY preparation were investigate in mice, rats, guinea pigs and rabbits. This preparation did neither show any effects on central nervous system, nor effects on algesia, nor epilepsia at the large doses of 3000 mg/kg po in mice or rats. However, the preparation showed hypothermic action at the doses of 330 and 1000 mg/kg po. In the guinea pig ileum, rat fundus strip and estrogenized rat uterus, DKY did not influence their tension at a concentration of 3$\times$10$^{-3}$ g/ml, and the spasmogenic actions produced by histamine, ACh and 5-HT were not blocked in the presence of DKY at 3$\times$10$^{-3}$ g/ml. The blood pressure and respiration were not considerably influenced at 10 mg/kg iv of DKY in rabbits. It did not influence the intestinal propulsion of mice and the normal gastric secretion of rats. These results may suggest that DKY preparation have little effects on central nervous, autonomic and gastrointestimal systems, except hypothermic action.

• 생태와환경
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• 제43권4호
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• pp.453-458
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• 2010

DOC (Dissolved Organic Carbon) is an operational terminology for organic carbon molecules dissolved in natural waters. DOC has been studied by ecologists extensively, because it plays a key role in various ecological functions such as substrates for secondary production and the carbon cycle. DOC also represents a substrate for microbial growth within potable water distribution systems, and can react with disinfectants (e.g., chloride) to form harmful disinfection by-products. In addition, residual DOC may carry with it organically bound toxic heavy metals. DOC in aquatic ecosystems may ultimately be transported to the oceans, or released back to the atmosphere by heterotrophic respiration, which can accelerate global climate change. There is evidence that DOC concentrations in aquatic ecosystems are increasing in many regions of the world including Europe, North America, and even in Korea. Land use changes, elevated temperature, elevated $CO_2$, recovery from acidification, and nitrogen deposition have been proposed as mechanisms for the trend. However, the key driving mechanism is yet to be conclusively determined. We propose that more extensive and longer-term observations, research of chemical properties of DOC, impacts of elevated DOC on environmental issues and interdisciplinary approaches are warranted as future studies to fill the gaps in our knowledge about DOC dynamics.

• 한국시조학회지:시조학논총
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• 제19권1호
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• pp.5-35
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• 2003

운율의 음악성을 중시하는 서정시로서의 시조 교육은 현재 현실과 괴이된 노래하는 창시조로 접근하거나 눈으로 읽고 머리로 생각하는 낭독의 연행양식으로 이뤄지고 있다. 그러나 시조 교육은 무엇보다도 자연스러운 호흡으로 길게 읊조리는 낭송의 연행양식에 초점이 맞춰져야 효율성을 지닌다. 이에 낭송의 기본원리인 율격과 율독을 해명하여 낭송법을 이론적으로 구체화했다. 그리고 시조의 감상과 창작의 효율성을 높이기 위한 방편으로 체계화된 시조 낭송법의 이론적 토대 위에서 입체화된 동영상으로서의 콘텐츠화를 시도했다. 그리하여 국민문학으로서의 시조의 미적 실체를 밝히는 하나의 단초가 되고자 했으며 또한 시조 학습의 효율성을 제고하여 국민의 정서를 순화하는데 일익을 담당하고자 했다.

• 대한한의진단학회지
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• 제11권2호
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• pp.128-140
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• 2007

Purpose: We performed this study to examine the correlationship between EEG complexity and impedance cardiography data using correlation analysis. Method: This study performed on 30 healthy subjects(16 males, 14 females). Before and after natural respiration, ICG data were recorded, and EEG raw data were measured by moving windows during 15 minutes. The correlation dimension(D2) was calculated from 15 minutes data. 8 channels EEG data were analysed with 9 index of ICG data by correlation analysis. Result: 1. ACI of impedance cardiography had significant correlationship with ch.4 of EEG complexity(p=0.03). 2. VI of impedance cardiography had significant correlationship with ch.3 of EEG complexity(p=0.034) and ch.4 of EEG complexity(p=0.017). 3. HR, TFC, PEP, LVET, STR of impedance cardiography had no significant correlationship with all of 8 channel EEG complexity. Conclusions: These results suggest that nonlinear analysis of EEG and impedance cardiography have some significant correlationship. And it can make out relationship between brain system and cardiovascular system. In the future, therefore, more study of these fields are necessary.

• Journal of Microbiology and Biotechnology
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• 제34권3호
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• pp.538-546
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• 2024

Cinnamaldehyde is a natural compound extracted from cinnamon bark essential oil, acclaimed for its versatile properties in both pharmaceutical and agricultural fields, including antimicrobial, antioxidant, and anticancer activities. Although potential of cinnamaldehyde against plant pathogenic bacteria like Agrobacterium tumefaciens and Pseudomonas syringae pv. actinidiae causative agents of crown gall and bacterial canker diseases, respectively has been documented, in-depth studies into cinnamaldehyde's broader influence on plant pathogenic bacteria are relatively unexplored. Particularly, Pectobacterium spp., gram-negative soil-borne pathogens, notoriously cause soft rot damage across a spectrum of plant families, emphasizing the urgency for effective treatments. Our investigation established that the Minimum Inhibitory Concentrations (MICs) of cinnamaldehyde against strains P. odoriferum JK2, P. carotovorum BP201601, and P. versatile MYP201603 were 250 ㎍/ml, 125 ㎍/ml, and 125 ㎍/ml, respectively. Concurrently, their Minimum Bactericidal Concentrations (MBCs) were found to be 500 ㎍/ml, 250 ㎍/ml, and 500 ㎍/ml, respectively. Using RNA-sequencing analysis, we identified 1,907 differentially expressed genes in P. carotovorum BP201601 treated with 500 ㎍/ml cinnamaldehyde. Notably, our results indicate that cinnamaldehyde upregulated nitrate reductase pathways while downregulating the citrate cycle, suggesting a potential disruption in the aerobic respiration system of P. carotovorum during cinnamaldehyde exposure. This study serves as a pioneering exploration of the transcriptional response of P. carotovorum to cinnamaldehyde, providing insights into the bactericidal mechanisms employed by cinnamaldehyde against this bacterium.

• 생태와환경
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• 제41권4호
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• pp.431-440
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• 2008

Turbid water or suspended sediment is associated with negative effects on aquatic organisms; fish, aquatic invertebrate, and periphyton. Effects of turbid water on fish differ depending on their developmental stage and a level of turbidity. Low turbid water may cause feeding and predation rates, reaction distance, and avoidance in fish, and it could make fish to die under high turbidity and long period. Therefore, it is very important to find out how turbid water or suspended sediment can affect fish in domestic watersheds. The objectives of this study were 1) to introduce international case studies and their standards to deal with suspended sediment, 2) to determine acute toxicity in 4 major freshwater fishes, and 3) to determine in relation to adverse effect of macroinvertebrates and fish. Impacts of turbid water on fish can be categorized into direct and indirect effects, and some factors such as duration and frequency of exposure, toxicity, temperature, life stage of fish, size of particle, time of occurrence, availability of and access to refugia, etc, play important role to decide magnitude of effect. A review of turbidity standard in USA, Canada, and Europe indicated that each standard varied with natural condition, and Alaska allowed liberal increase of turbidity over natural conditions in streams. Even though acute toxicity with four different species did not show any fatal effect, it should be considered to conduct a chronic test (long-term) for more detailed assessment. Compared to the control, dominance index of macroinvertebrates was greater in the turbid site, whereas biotic index, species diversity index, species richness index, and ecological score were smaller in the turbid site. According to histopathological analysis with gills of macroinvertebrate and fishes, morphological and physiological modification of gills due to suspended sediments can cause disturbance of respiration, excretion and secretion. In conclusion, in order to maintain good and healthy aquatic ecosystem, it is the best to minimize or prevent impact by occurrence of turbid water in stream and reservoir. We must make every effort to maintain and manage healthy aquatic ecosystem with additional investigation using various assessment tools and periodic biomonitoring of fish.

• Applied Microscopy
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• 제28권4호
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• pp.435-446
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• 1998

It is suggested that Urechis unicinctus is a filler feeder as like many tide and watery invertebrates which filtrate food materials by ciliary movement. However, the structure of the filter is not yet known in U. unicinctus, nor the filtering mechanism is not well understood. This study reveals ciliated epithelial cells in the foregut and the features of the cilia are good accord with that of known filtrating apparatus of other tide animals. This may implies that the foregut is in function of filtration and the food materials are filtrated by the ciliary movement. With the observation of the filtrating apparatus in the foregut, the intestine of U. unicinctus can be functionally compartmented into 3 parts. These are already known midgut and hindgut in function of digestion and respiration respectively, and the foregut in function of filtrating apparatus for foods. The filtrating apparatus of U. unicinctus is composed of the pseudostratified columnar epithelial cells with numerous cilia. The cilia are well differentiated kinocilia with the typical microtubule pattern, kinetosome and cilia roots. There are two kinds of striated cilia roots, the main root and the accessory root. The main root is extended perpendicularly from the cell surface to basement membrane and the short accessory root is branched with an acute angle of about $80^{\circ}$ from the main root at level of basal plate of the kinetosome. The spacial approaches of the main root with the large fused form of mitochondria is one of the characteristic features which might be in structural consideration an intimate association between energy source and energy mass consuming cell organelles.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 1999년도 정기총회 및 춘계 공동 학술발표회
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• pp.149-156
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• 1999

In the United States (U.S.), the monitored natural attenuation (MNA) approach has been used as an alternative remedial option for organic and inorganic compounds retained in soil and dissolved in groundwater. The U.S. Environmental Protection Agency (EPA) defines the MNA as“in-situ naturally-occurring processes include biodegradation, diffusion, dilution, sorption, volatilization, and/or chemical and biochemical stabilization of contaminants and reduce contaminant toxicity, mobility or volume to the levels that are protective of human health and the environment”. The Department of Soil Environment. National Institute Environmental Research (NIER) is in the process for demonstrating the MNA approach as a potential remedial option for the BTEX contaminated site in Uiwang City. The project is charactering the research site in terms of the nature and extend of contamination, biological degradation rate, and geochemical and hydrological properties. The microbial-degradation rate and effectiveness of nutrient and redox supplements will be determined through laboratory batch and column tests. The geochemical process will be monitored for determining the concentration changes of chemical species involved in the electron transfer processes that include methanogenesis, sulfate and iron reduction, denitrification, and aerobic respiration. Through field works, critical soil and hydrogeologic parameters will be acquired to simulate the effects of dispersion, advection, sorption, and biodegradation on the fate and transport of the dissolved-phase BTEX plume using Bioplume III model. The objectives of this multi-years research project are (1) to evaluate the MNA approach using the BTEX contaminated site in Uiwang City, (2) to establish a standard protocol for future application of the approach, (3) to investigate applicability of the passive approach as a secondary treatment remedy after active treatments. In this presentation, the overall picture and philosophy behind the MNA approach will be reviewed. Detailed discussions of the site characterization/monitoring plans and risk-based decision-making processes for the demonstration site will be included.