• Microbiology and Biotechnology Letters
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• v.40 no.2
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• pp.83-91
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• 2012

Quorum sensing (QS) is a cell-to-cell communication system, which is used by many bacteria to regulate diverse gene expression in response to changes in population density. Bacteria recognize the differences in cell density by sensing the concentration of signal molecules such as N-acyl-homoserine lactones (AHL) and autoinducer-2 (AI-2). In particular, QS plays a key role in biofilm formation, which is a specific bacterial group behavior. Biofilms are dense aggregates of packed microbial communities that grow on surfaces, and are embedded in a self-produced matrix of extracellular polymeric substances (EPS). QS regulates biofilm dispersal as well as the production of EPS. In some bacteria, biofilm formations are regulated by c-di-GMP-mediated signaling as well as QS, thus the two signaling systems are mutually connected. Biofilms are one of the major virulence factors in pathogenic bacteria. In addition, they cause numerous problems in industrial fields, such as the biofouling of pipes, tanks and membrane bioreactors (MBR). Therefore, the interference of QS, referred to as quorum quenching (QQ) has received a great deal of attention. To inhibit biofilm formation, several strategies to disrupt bacterial QS have been reported, and many enzymes which can degrade or modify the signal molecule AHL have been studied. QQ enzymes, such as AHL-lactonase, AHL-acylase, and oxidoreductases may offer great potential for the effective control of biofilm formation and membrane biofouling in the future. This review describes the process of bacterial QS, biofilm formation, and the close relationship between them. Finally, QQ enzymes and their applications for the reduction of biofouling are also discussed.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.20 no.1
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• pp.37-42
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• 1984

This paper deals with the characterics of the stability of uncontinuous plate structures with cracks. The relation between the J-intergal of the cracks existing in the stress-concentrated regions and local strain are investigated experimentally and theoretically. The BEM(boundary element method)analysis and test results lead to the follow conclusions: 1. A non-dimensional J was computed in a plate stress and strain condition for several kind of loads and crack types. The J design curves are defined as follows: J sub(E)/$\sigma$ sub(y) super(2) a=3.345(e/e sub(y) ) super(2) at e/e sub(y)$\leq$1 J sub(E)/$\sigma$ sub(y) super(2) a=3.345(e/e sub(y) ) at e/e sub(y)$\geq$1 2. Use of this curve provides a good estimation for the uncontinuous plate structures with cracks existing in the stress and strain concentrated region. 3. The stability of the characteristics is mainly depenent upon not the length of cracks but the type of the cracks.

• Journal of Korea Entertainment Industry Association
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• v.13 no.8
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• pp.117-130
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• 2019

After Marx, the issues regarding human labour have been the alienation towards production means and the distributive justice. Fourth industrial revolution and development of AI(Artificial Intelligence) opened the possibility of a independent production and economy system absolutely excluding against human nature and labour. Using robots and AI will deepen demarcation between living things and one not having life, separating the intelligence from the consciousness. At present, so called pre-stage of post human, seeking interests for life, new social relationship and new community will be increased as well. We can understand that interests for small community, self-sufficiency, dailiness, food and body in this context is increasing too. Representative trend towards this cultural phenomena is called as the 'Kinfolk culture.' Work-life balance, 'Aucalme', 'Hygge', 'So-Hwak-Haeng'(a small but reliable happiness) are the similar culture trends as. Vital capitalism, presented by O-Yong Lee, seeks focusing onto living things principles, e.g. 'topophilia', 'neophilia', and 'biophilia' as the dynamics looking for the history substructure, not class struggle and conflicts. He also argues the 'Vital Capitalism' be regarded as a new methodology to anticipate a social system after post human era. G. Deleuze said "arts is another expression method for existential philosophy. It gives a vitality onto philosophy and gives a role to letting abstract concept into definite image." We can find a lot cases arts' imagination overcomes critical point of scientific prediction power in the future prediction. This paper reviews ideas and issues of 'vital capitalism' in detail and explorers imaginating initial ideas of vital capitalism in the film 'Little Forest.'

• Journal of Sasang Constitutional Medicine
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• v.11 no.1
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• pp.41-61
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• 1999

The purpose of this article is to investigate Lee Je-rna'os viewpoint of Morpho-Image. In the first place, I will define the viewpoint of Morpho-Image as the the structure of recognition and study it through bibliographic study on Lee Je-ma's work. The conclusions summarized as follows; 1. The structure of recognition, represented in "Gyukchigo(格致藁)" "Dongyi Soose Bowon Sasang Chobonkyon(東醫壽世保元四象草本卷)", is based on Taigi(太極), Liangyi(兩儀), Sasang(四象). There are the mind of Taigi(太極), the mind of Liangyi(兩儀) separated from Taigi(太極), the mind of Sasang(四象) separated from Liangyi(兩儀). The mind of Taigi(太極) is the mind of center, the mind of Liangyi(兩儀) is the mind of the mind and body(or the wisdom and action). Two axis, the mind(or wisdom) and the body(or action), cross and make Sasang(四象), affair-mind-body-object which classifies all affairs and objects of humans, society, and the universe as four types. 2. Lee Je-ma summarized everything in view of Sasang(四象), Sasang(四象) in view of Liangyi(兩儀), Liangyi(兩儀) in view of Taigi(太極). 3. The procedure of recognition above is described in , , . Such is transformed in terms of human body and described in .

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.6
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• pp.1293-1300
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• 2001

We surveyed dietitians'perception on usage of cook/chill vegetables, The questionnaires were distributed to 245 dietitians working in elementary schools and other institutions in Busan area. According to the survey, 75.9% of the dietitians perceived that minimally processed ready -to-use vegetal)toes would be helpful for the institutional foodservice They answered that problems of vegetable usage in the foodservice mainly come from long preparation time (45.4%), a large quantity of leftover (13.1%), and a high ratio of disuse (16.0%). Degree of preparedness from raw vegetables was highest for garlic, and was in tile order of platicodcm, onions, carrots, Potatoes, Korean cabbage and radish.40.9% of the dietitians answered that it was necessary Ic develop cook/chill vegetables in their institute restaurants. The high career group ( >6 yrs.) was, however, significantly (p<0.05) negative against the use of cooHchill vegetables. The dietitians were expecting that developing cook/chill vegetables would save cooking time and processes (4.43/5.00), and reduce waste (4.53/5.00) greatly. They also estimated that focal hygiene and quality would be improved, and labor cast be reduced moderately. On the other hand, they thought that the cost of flood would not be reduced.