• Title/Summary/Keyword: culture.ecology

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Effects of Cadmium on Radial Growth and Dry Mass Production of Ectomycorrhizal Fungi

  • Kim, Chang-Gi;Power, Sally Anne;Bell, John Nigel Berridge
    • The Korean Journal of Ecology
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    • v.27 no.5
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    • pp.301-306
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    • 2004
  • The sensitivity to Cd of three ectomycorrhizal fungi, Paxillus involutus, Suillus bovinus and Rhizopogon subcaerulescens, was assessed and compared in terms of radial growth and dry mass production, using both agar and liquid culture. The radial growth of S. bovinus and R. subcaerulescens was significantly reduced at the lowest concentration (0.1mg Cd/L). The 50% effective concentration (EC$_{50}$) values calculated from radial growth rates of the ectomycorrhizal fungi showed that the sensitivity of the fungi to Cd was greatest in S. bovinus and lowest in R. subcaerulescens. Cadmium addition also significantly decreased dry mass production of the ectomycorrhizal fungi. The sensitivity of the fungi to Cd in terms of dry mass production, was greatest in S. bovinus and lowest in P. involutus. Higher growth rates of P. involutus and melanisation of R. subcaerulescens appeared to contribute to reduced Cd toxicity.

Descent Systems, Paternity Uncertainty and Cousin-directed Altruism

  • Jeon, Joong-Hwan;Yoon, Ji-Young;Choe, Jae-Chun
    • Journal of Ecology and Environment
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    • v.31 no.3
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    • pp.243-247
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    • 2008
  • Jeon and Buss (2007) found that human altruistic tendencies towards different categories of cousins are adaptively regulated as a consequence of paternity uncertainty. Since the study sample was drawn from a large US city where the effects of patrilineality may be week, the question of whether descent systems also independently affect cousin-directed altruism remained unanswered. We replicated the cousin-directed altruism study in a population of urban Korean college students, who have lived in a highly patrilineal society. As predicted, mother's sister's children were favored the most, followed by both mother's brother's and father's sister's children. Contrary to our predictions, however, father's brother's children was more, not less, favored than either mother's brother's or father's sister's children. We discuss why this cross-cultural difference may be observed with regard to the highly patrilineal culture in Korea.

Effect of Alcohol and Tobacco on Sucrose Fermentation by Streptococcus mutans (알콜과 담배가 Streptococcus mutans의 자당발효에 미치는 영향에 관한 연구)

  • 김재훈
    • Korean Journal of Health Education and Promotion
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    • v.7 no.2
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    • pp.71-77
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    • 1990
  • Streptococcus mutans 10449 was cultured in sucrose-containing BHI broth with ethyl alcohol of different concentration from 1% to 18%, The pH of culture media was from pH 7.00 to pH 5.00. Tobacco smoke and tobacco extract were also used. Ethyl acohol began to inhibit sucrose fermentation by S. mutans at 2% and completely inhibited it between 9% and 18%. The lower the pH of media was, the stronger the inhibition of ethyl alcohol became. 9% Ethyl alcohol completely inhibited sucrose fermentation by S. mutans below pH 5.50, Inhibition by tobacco extract was obvious, but it did not inhibit the growth of S. mutans also. Therefore, the increase of caries activity in drinkers and smokers could be the result of indirect effect of alcohol and tobacco by oral ecology, behavior, or systematic course, rather than the result of direct effect of alcohol and tobacco to plaque bacteria and their metabolism.

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A Method for Comparing Multiple Bacterial Community Structures from 16S rDNA Clone Library Sequences

  • Hur, Inae;Chun, Jongsik
    • Journal of Microbiology
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    • v.42 no.1
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    • pp.9-13
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    • 2004
  • Culture-independent approaches, based on 16S rDNA sequences, are extensively used in modern microbial ecology. Sequencing of the clone library generated from environmental DNA has advantages over fingerprint-based methods, such as denaturing gradient gel electrophoresis, as it provides precise identification and quantification of the phylotypes present in samples. However, to date, no method exists for comparing multiple bacterial community structures using clone library sequences. In this study, an automated method to achieve this has been developed, by applying pair wise alignment, hierarchical clustering and principle component analysis. The method has been demonstrated to be successful in comparing samples from various environments. The program, named CommCluster, was written in JAVA, and is now freely available, at http://chunlab.snu.ac.kr/commcluster/.

Effects of naturally Occurring KDICicals from Pinus koraiensis on Callus Induction and Germiculture (잣나무 天然化學物質이 Callus 誘起 및 細菌培養에 미치는 影響)

  • Kil, Bong-Seop;Young-Sik, Kim;D;Kyeong Won Yun
    • The Korean Journal of Ecology
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    • v.16 no.3
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    • pp.275-285
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    • 1993
  • To study allelopathic porential of naturally occurring substances emitted from Pinus koraiensis, the effects of water exrracts and volatile substances of the tree on callus induction and bacterial culture were examined. The induction and growth of callus were inversely proportional to the concentration of the extracts and of the essential oils supplemnted to Murashige and Skoog's media. However, low concentration(5μl/l) of essential oil promoted callus growth. In germiculture of several bavteria, the extracts of Pinus koraiensis markedly showed the inhibitory effects on bacterial growth. It was, therefore, confirmed that the KDICical substances of Pinus koraiensis tree clearly showed that biological toxic activity at high concentrations.

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Genetic phenomena for the pb and zu tolerance in plants (식물의 납과 아연의 내성에 관한 유전현상)

  • Yun, Jeoung-Ok;Lee, In-Sook
    • The Korean Journal of Ecology
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    • v.15 no.2
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    • pp.173-180
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    • 1992
  • Pb, Zn tolerance of phaseolus multiflorus was investigated, based on the elongation of root and stem, pollen Germination and progeny quality in various pb, zn concentrations. The result obtained by water culture showed that the growth of roots and steams of phaseolus multiflorus from pb-zn mine site is less inhivited than that of the control site. The flower of phaseolus multiflorus from which pollen was taken were grown without added pb, zn and percent germination of pollen observed in a range of pb, zn concentrations. The percent germination of pollen from pb-zn mine site was higher than the control site. phaseolus multiflorus collected at a pb-zn mine site and the control site was site were grown at different pb, zn concentrations, its progeny was retreated with same concentrations of pb-zn mine site was more vigorous than the control site. thus, pb-zn tolerance was able to expressed in both pollen and sporophytes.

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Eco-car Manufacturing Activities as Engineering Design Education Subject in Suzuka National College of Technology

  • Mori, Kunihiko;Sakamoto, Hidetoshi;Ohbuchi, Yoshifumi
    • Journal of Engineering Education Research
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    • v.15 no.5
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    • pp.25-30
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    • 2012
  • "The engineering education program for environmental intention and value creation" has been executed from 2008 to 2010 in Suzuka National College of Technology, which program was promoted as "Good Practice for Education" by Ministry of Education, Culture, Sports, Science and Technology Japan. "Eco-car project" is one of these practical ecology/environment education programs. The project's members have been learning and researching the environmental managements by the process of design, manufacturing, and assembly of solar car, highly effective fuel consumption car (Eco-run car), electric vehicle and fuel-cell car. Also this project was supported by some professional experts of the local industries and community. The students learned the actual industrial technique, the engineering management and the structure of local industries by this project. In this paper, the environmental intention engineering design education with local industry collaboration is introduced.

The Impacts of Two-day Weekend System on Living Culture Along with Efficient Countermeasures - Taiwan Experience

  • Hsu Meei-Ruey
    • International Journal of Human Ecology
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    • v.3 no.1
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    • pp.137-150
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    • 2002
  • The purpose of this study was to explore the amis of two-day weekend system, the attitudes of people towards the system, and people's actions taken under the system implementation in Taiwan. Several other factors together with the implementation of Two-day Weekend System and at least three interrelated factors are the spurs for families to adjust their family life styles. the interrelated factors are changing economy, changing demography, and changing technology. The strategies available for families are as follows: 1. Keeping simple family life 2. Looking for flexible jobs other than a fixed daytime schedule. 3. Taking the advantages of information technology. 4. Working and getting together with family members at home and outside of the home.

The Role of Parent-Child Relationships in Developing Self-Authorship Among Korean College Females

  • Lee, So-Young;Meszaros, Peggy S.;Creamer, Elizabeth G.;Laughlin, Anne;Burger, Carol J.
    • International Journal of Human Ecology
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    • v.7 no.1
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    • pp.111-119
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    • 2006
  • The purpose of our study is to explore dynamic mechanisms within families and self-authored decisions among Korean female college students. In particular, we investigated how parent-child interactions influence the development of self-authorship and self-authored decisions within Korean culture through interviews with 14 female college students. Results showed unique cultural influences on how female college students interacted with parents and interpreted and reflected parents' opinions in their self-authored decisions. These results suggest further research on gender differences and complex family influences on self-authored decisions within cultural contexts.

A Comparative analysis of the Pre- and Post-Construction Image Analysis of the Nakdong Estuary as Coastal Tourism Resource

  • Yhang Wii-Joo;Cho Yoon-Shik
    • Journal of Environmental Science International
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    • v.14 no.10
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    • pp.905-910
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    • 2005
  • The purpose of this study is the comparative analysis of Susan citizens' images of Eulsook-do as a coastal tourism destination before and after the construction of a road bridge across the Nakdong estuary in order to analyze local people's changes in leisure patterns. Analysis of the images of a pre-construction Eulsook-do that people aged both 40 and less and 50 and more had on five dimensions showed values higher than zero(0) that suggests neutral image, while their images of a post-construction Eulsook-do showed the shrinking size of pentagon on all five dimensions: ET(Entertainment), CA(Culture & Art), EE(Environment & Ecology), RC(Recreation) and LP(Leports) dimensions. Its pre- and post- construction image analysis conducted 20 years after it came to be built finds that the road bridge construction has led to the ecological, environmental disruption of the coast and the lower Nakdong river, having negative influence on the images of Eulsook-so.