• Title/Summary/Keyword: hand culture

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Control of Both Foam and Dissolved Oxygen in the Presence of a Surfactant for Production of $\beta$-Carotene in Blakeslea trispora

  • Kim, Seon-Won;Lee, In-Young;Jeong, Jae-Cheol;Lee, Jung-Heon;Park, Young-Hoon
    • Journal of Microbiology and Biotechnology
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    • v.9 no.5
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    • pp.548-553
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    • 1999
  • A production of $\beta-Carotene$was attempted in a fed-batch culture of Blakeslea trispora by controlling both foam and dissolved oxygen in the presence of surfactant, Span 20. Results obtained from the shake flask cultures indicated that a high concentration of dissolved oxygen was needed for both cell growth and $\beta-Carotene$ synthesis, and the optimal concentration of glucose was found to be in the range of 50-100 g/l. In order to maintain the dissolved oxygen concentration level at higher than 50% of air saturation, pure oxygen was automatically sparged into the medium with air. Foam was controlled by bypassing air from the submerged aeration to the headspace in response to the foam that was caused by Span 20. High agitation speed was found to be detrimental to the cell growth due to shear damage, even though it provided sufficient dissolved oxygen. On the other hand, a low aeration speed caused stagnant regions in the fermentor because of improper mixing. Thus, for the fed-batch operation, agitation speed was increased gradually from 300 to 700 rpm to prevent cell damage at the initial stage of fermentation and to give efficient mixing for a viscous culture broth as the culture proceeded. By controlling dissolved oxygen and foam, a high concentration of $\beta-Carotene$otene (1,190 mg/l) was obtained in 6 days of the fed-batch culture of B. trispora with 2.5% of the dry cell weight, which was approximately 5 times higher than that of the batch cultures.

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Empirical Model Building and Analysis for Performance of Social Enterprises (사회적 기업의 성과분석 실증모델 구축 및 분석)

  • Lim, Kyung-Soo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.3
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    • pp.1436-1441
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    • 2014
  • Social enterprise has been increasingly recognized for as important economic and social contribution to modern society. Recently, many efforts and academic researches related to social enterprise are now emerging from practitioners and academics. This work focused on the key elements affecting the performance of social enterprises such as specifically social entrepreneurship, relationship-oriented organizational culture and government support policy. In this empirical model, two performance variables such as economic and social performance represent the dependent variables. And the size and age of the social enterprises are the controlled variables. By analyzing survey data of 107 social enterprises interesting and meaningful results are obtained. Social entrepreneurship influenced economic and social performance of social enterprises. And relationship-oriented organizational culture influenced economic and social performance of social enterprises. On the other hand, government support policy influenced economic performance of social enterprises, but did not influence its social performance. The developed empirical model of social entrepreneurship in this study showed that community-oriented organizational culture and government policy are important factors for the efficient and successful management of social enterprises in Korea.

Effects of the microbiological properties and pathogenicity of Photobacterium damselae subsp. damselae under different culture conditions (배양 조건이 Photobacterium damselae subsp. damselae의 미생물학적 성상 및 병원성에 미치는 영향)

  • Kwon, Mun-Gyeong;Cho, Byoung-Youl;Park, Myeong-Ae
    • Journal of fish pathology
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    • v.22 no.3
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    • pp.239-251
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    • 2009
  • The effects of microbiological properties and pathogenicity of Photobacterium damselae subsp. damselae were investigated under different culture conditions, temperature, pH, NaCl and iron concentration on culture media. Favorable conditions for bacterial growth were between 15-30${^{\circ}C}$, pH 5-9, 0-4% NaCl concentration and iron contents of over 10 mM, whereas the bacterial growth was inhibited under iron chelator existence. When P. damselae was cultured in iron-limited tryptic soy broth, total protein concentration of extracellular products, cytotoxic ability of ECPs on cell line, bacterial viability in flounder serum, phospholipase and siderophore activities of ECPs were significantly increased. On the other hand, the activities of P. damselae cultured under iron-added conditions were decreased. In this study, the iron-limited conditions were similar to the host in which iron concentration is low. During infection caused by P. damselae, the conditions could be related to the pathogenesis of the pathogen.

Effects of Planting Density and Fertilizer Level on Agronomic Characteristics and Yield of Solanum njgrum L. (재식밀도와 시비량이 야생약초 까마중(Solanum njgrum L.)의 주요 형질과 수량에 미치는 영향)

  • 최성규;이종일
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.36 no.4
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    • pp.340-344
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    • 1991
  • This study was investigated to find out the optimum planting densities fo Solanum njrum L. about growth characters. yield components and yield at 6 planting densities by direct sowing culture. The results obtained are summarized as follows: Studying the correlationship. the highly negative significances were found between planting densities and fresh eights weights per plant, on the other hand, the highly positive significances were found between planting densities and plant height. Plant height was long in dense planting, and short in spacious planting by direct sowing culture. Stem diameter was thick in spacious planting. and was thin in dense planting. Fresh wt. per plant was decreased in dense planting and was increased in spacious planting by direct sowing culture. Yield was highest in dense planting densities (10 x 20cm : 50plants/$m^2$) by direct sowing culture. Fertilizing ((N: P$_2$O$_{5}$ $K_2$O=6 : 6 : 6Kg/10a) was increased than without fertilizing because plant height and number of branch was good.d.

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Organizing Korean International Broadcasting's Programming Strategy and Channel Positioning map (한국 해외홍보방송의 편성전략과 채널 포지셔닝 설정)

  • Yoon, Hong Keun
    • The Journal of the Korea Contents Association
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    • v.13 no.4
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    • pp.97-103
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    • 2013
  • The research is centered towards analyzing the differentiation of the characteristics and organization of programming strategy and channel positioning by selecting Korean International Public Relations Broadcasting Stations Arirang TV and KBS World. According to the results, Arirang TV positions Korean culture content-implied educational programs as their strategy while KBS World places the main programs of KBS1, 2TV with many entertainment programs such as dramas and entertainment shows. Arirang TV's programming strategy is well-fulfilling the purpose of promoting Korea's culture contents by organizing their programming with documentaries, tourist information, and daily living information. On the other hand, KBS World works as the agent of the spread of the Korean Wave by filling their program with dramas and K-pop programs such as . Due to the difference in programming strategy of these two broadcasting stations, Arirang TV has positioned itself as a diplomatic channel to spread Korean culture and KBS World a channel representing the Korean Wave. However, there are problems of inefficiency due to recurrent investments because of the fact that both broadcasting stations' programming strategy is to promote Korean culture and spread the Korean Wave by aiming similar targets such as foreigners or overseas Koreans.

Ontology-based Culture·Tourist Attraction Search Application (온톨로지 기반의 문화·관광지 검색 어플리케이션 구현)

  • Hwang, Tae-won;Seo, Jung-hee;Park, Hung-bog
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2017.05a
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    • pp.772-774
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    • 2017
  • Currently, there are many simple searches for local culture and tourism, but systematic information retrieval using ontology technology is weak. The keyword-based search, which is an existing search method, derives a search result that is different from a user's wanted intention. On the other hand, semantic search using ontology constructs shows the information related to the search term by creating a relation between words and words. Therefore, when tourists search for cultural and tourist attractions in the area, they provide information that includes meaning relevance in the search results. If the ontology provides information on the culture, sightseeing area, transportation, Can be more easily grasped. In this paper, we propose an ontology-based retrieval system based on culture and tourist sites utilizing public institutions database by using mobile application by extending search system which relied only on existing internal database to provide accurate and reliable information to users. This efficient structure of the ontology makes it possible to provide information suitable for the user quickly and accurately.

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Effect of Triton X-100 on Compactin Production from Penicillium citrinum

  • Park, Du-Bok;Cho, Ki-An;Cha, Wol-Suk;Ryu, Seong-Ryeol
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.9 no.3
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    • pp.171-178
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    • 2004
  • Glucose alone was found to be the most effective carbon source for producing compactin. An initial glucose concentration of 40 g/L gave the highest compactin concentration of 250mg/L. Among the various nitrogen sources, when 5g/L of pharmamedia and soybean meal as the sole nitrogen source were used, respectively, the compactin concentration was higher than 250mg/L. Especially, in the case of the mixture of 6 g/L of pharmamedia and 8 g/L of soybean meal, the compactin concentration was 400mg/L. To select the best surfactant for effective compactin production, various surfactants were investigated. When Triton X-100 was used, the maximum compactin concentration was 445mg/L. With the initial concentration ranging from 1.5 to 2.0 g/L, the compactin concentration was the highest at 465-450mg/L. The cell concentration was similar to that of the control without the addition of Triton X-100. On the other hand, when the above 4.0 g/L of Triton X-100 were used, the cell concentration decreased. Using the based results, the continuous fed-batch cultures by adding the Triton X-100 were carried out for 10 days in an air-lift bioreactor. When 1.5 g/L of Triton X-100 was added to the culture broth at 0, 4, and 8 days of culture, respectively, the compactin production was increased with the increase of culture time. The maximum compactin concentration after 10days of culture was 1,200mg/L, which was about 2.0-fold higher than that of the control without the addition of Triton X-100.

Skin photoaging in reconstituted skin culture models (3D 피부세포 배양계를 이용한 피부광노화 연구)

  • 강상진
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.25 no.2
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    • pp.59-75
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    • 1999
  • Skin is continuously exposed to external stimuli including ultraviolet radiation, which is a major cause of skin photoaging. According to recent discoveries, UVA with a lower energy but deep-penetrating properties, compared to UVB, is likely to play a major part in causing skin photoaging. The clinical and histochemical changes of photoaging are well characterized, but the biochemical mechanisms are poorly understood partly due to the lack of suitable experimental systems. In this work, three-dimensional, reconstituted skin culture models were prepared. After certain period of maturation, the equivalent models were shown to be similar in structure and biochemical characteristics to normal skin. Mature dermal and skin equivalent models were exposed to sub-lethal doses of UVA, and the effects of UVA relevant to dermal photoaging were monitored, including the production of elastin, collagen, collagenase(MMP-1), and tissue inhibitor of metalloproteinases-1 (TIMP-1). Interestingly, dermal and skin equivalents reacted differently to acute and chronic exposure to UVA. Elastin production was increased as soon as one week after commencing UVA irradiation by chronic exposure, although a single exposure failed to do so. This early response could be an important advantage of equivalent models in studying elastosis in photoaged skin. Collagenase activity was increased by acute UVA irradiation, but returned to control levels after repeated exposure. On the other hand, collagen biosynthesis, which was increased by a single exposure, decreased slightly during 5 weeks of prolonged UVA exposure. Collagenase has been thought to be responsible for collagen degeneration in dermal photoaging. However, according to the results obtained in this study, elevated collagenase activity is not likely to be responsible for the degeneration of collagen in dermal photoagig, while reduced production of collagen may be the main reason. It can be concluded that reconstituted skin culture models can serve as useful experimental tools for the study of skin photoaging. These culture models are relatively simple to construct, easy to handle, and are reproducible Moreover the changes of dermal photoaging can be observed within 1-4 weeks of exposure to ultraviolet light compared to 4 months to 2 years for human or animal studies. These models will be useful for biochemical and mechanistic studies in a large number of fields including dermatology, toxicology, and pharmacology.

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Effect of Various Fungi on the Aflatoxin Productivity in tile Culture of Asp. Flavus (진균류(眞菌類)의 상호작용(相互作用)에 의한 Aflatoxin 생성능(生成能)에 관(關)한 연구(硏究))

  • Kim, Eu-Ju;Chung, Yong;Kwon, Sook-Pyo
    • Journal of Preventive Medicine and Public Health
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    • v.9 no.1
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    • pp.77-86
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    • 1976
  • This study was attempted to know that the interactions of various fungi, and methionine and $MgSO_4$ introduced as the substrate of culture media for fungi were affected to produce aflatoxins by Asp. flavus. 5 different fungi were isolated from the fermented soybean mash and were cultured in Chemically Defined medium (C. D. media) and soybean mash at $25^{\circ}C$ for 10 days. (1) It was confirmed that Asp. flavus produced aflatoxins in the C. D. medium and soybean mast, but that Asp. niger, Asp. oryzae, Asp. awamori and Asp. terreus did not produced them respectively. (2) Asp. flavus cultured with Asp. niger did not produce aflatoxins in C. D. medium, but produced in soybean mash, in other hand, Asp. flavus with other fungi except Asp. niger produced aflatoxins in C. D. medium and soybean mash. (3) The growth of fungi were more prosperous in the seperate culture than in the mixed culture. (4) In the C. D. medium added 20% of cultured medium of Asp. niger, Asp. flavus did not produce aflatoxins but other cultured medium did not prohibit the production of aflatoxins by Asp. flavus. (5) On the contrary, $MgSO_4$ increasing the productivity of aflatoxins by Asp. flavus in the C. D. medium, methionine known as one of precursor of aflatoxins did not affected the increasing productivity with significance.

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The Influence of Childcare Teachers' Empathy Ability and teaching flow on Happiness (보육교사의 공감능력 및 교수몰입이 행복감에 미치는 영향)

  • Park, SungYeon;Cho, Sung-je
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.6
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    • pp.299-304
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    • 2021
  • This study examined the effects of childcare teachers' empathy, teaching commitment, and feelings of happiness. The subjects were 111 childcare teachers in U city. The frequency, reliability, and correlation analysis were performed using the SPSS 22.0 program, and regression analysis was performed on the causal relationship between the variables. First, the childcare teacher's cognitive empathy factor had a positive effect on the sense of happiness. On the other hand, the emotional empathy factor, a sub-factor of the empathy ability, did not affect the feeling of happiness. Second, the childcare teacher's teaching commitment had a significant positive effect on happiness. This means that a higher cognitive empathy factor, a sub-factor of the childcare teacher's empathy ability, resulted in a higher sense of happiness. Moreover, a higher instructional commitment factor indicated a higher sense of happiness. This study provides basic data for preparing measures to improve the sense of happiness of childcare teachers by grasping the relationship between childcare teachers' empathy ability, teaching commitment, and feelings of happiness.