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Studies on the Dynamics of Fish Community in Wonju Stream (원주천의 어류군집 동태)

  • Choi, Jun-Kil;Byeon, Hwa-Kun;Seok, Hyung-Kun
    • Korean Journal of Ecology and Environment
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    • v.33 no.3 s.91
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    • pp.274-281
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    • 2000
  • The dynamic of fish community was investigated in the Wonju stream from March 1998 to February 1999. The collected species during the surveyed period were 24 species belonging to eight families. Eight species (33%) of them were endemic species of Korea. According to relative abundance in the studied areas, Moroco oxycephalus (30.7%), Zacco platypus (29.6%), Carassius auratus (10%), Pseudogobio esocinus (9.4%) and Rhinogobius brunneus (3.6%) dominated. Hemibarbus longirostris, Pungtungia herzi, Squalidus japonicus coreanus, Zacco temmincki, Cobitis rotundicaudata, Silurus asotus, Silurus microdorsalis and Micropterus salmoides were rare to the areas, which occupied less than 0.1% in relative abundance. Dominant species was M. oxycephalus (Kumda-ri, Kwanseol-dong, Hanggu-dong, heongyang-ri), Z. platypus (Gaeun-dong) and C. auratus (Jusan-ri). It was revealed by the analysis of community that St. 3 was the most diverse among all study stations. Coreoleuciscus splendidus and Coreopera herzi have been assumed vanished in the Wonju stream. The species occurring in suddenly decreasing trend were Microphysogobio yaluensis, Liobagrus andersoni, Cottus poecilopus and R. brunneus. The species occurring in representative increasing trend were Cyprinus carpio, C. auratus, P. esocinus, M. oxycephalus, and Z. platypus.

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Why Does m-Methyl Substituted Pesticides Show Higher Insecticidal Activity? On the Phenyl N-methylcarbamate and m-xylyl-N-methylcarbamate Derivatives (왜 m-methyl 치환 살충제들은 강한 살충작용을 나타낼까? -Phenyl N-methylcarbamate와 m-xylyl-N-methylcarbamate 유도체들에 관하여-)

  • Sung, Nack-Do
    • Applied Biological Chemistry
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    • v.32 no.2
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    • pp.170-177
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    • 1989
  • In order to seek the molecular basis of higher insecticidal activity of the carbamates with two methyl groups, m-xylyl-N-methylcarbamate(MXNMC) than the corresponding unsubstituted phenyl N-methylcarbamate(PNMC), these two derivatives have been studied by molecular orbital(MO) theoretically using extended $H\ddot{u}ckel$ theory(EHT), and analysis of regression and linear free energy relationship(LFER). The most stable stereo structure(Z, Z) shows that the phenyl group occupies vertical(${\theta}=90^{\circ}$) position on the plane of the N-methylcarbamyl group. Regression analysis shows that especially good correlation exists between the $pI_{50}$ values and the calculated MO quantities when the hydrogen atomic charge of metaposition and of m-methyl groups, and LUMO energy are taken as variables. The LFER analysis on the carbamylation indicates that field(F) effect(60%) is slightly larger than resonance(R) effect(40%) in PNMC(E>R), whereas, in case of MXNMC, R effect(98.6%) is much larger than F effect(1.4%)($R{\gg}F$). From the basis on the findings, the enhancement of insecticidal activity of MXNMC may be the result of hyperconjugation by m-methyl groups.

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Mechanism of gemcitabine-induced apoptosis (Gemcitabine의 세포사멸 기전 연구)

  • Seol, Jae-Won;Lee, You-Jin;Kang, Dong-Won;Kang, Hyung-Sub;Kim, Nam-Soo;Kim, In-Shik;Park, Sang-Youel
    • Korean Journal of Veterinary Research
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    • v.45 no.4
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    • pp.495-500
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    • 2005
  • The nucleoside analogue gemcitabine (2', 2-difluorideoxycytide) is potential against a wide variety of solid tumors and considered to be one of the most active drugs in the treatment of non-small cell lung cancer (NSCLC). In this study, we investigated the signals of gemcitabine-induced apoptosis, especially in point of caspase pathway in A549. We exposed A549 cells to gemcitabine for dose/time dependent manner and the results showed that gemcitabine induced apoptotic cell death in a time/dose-dependent manner. We also treated to gemcitabine and Z-VAD-fmk as a pan-caspase inhibitor for 24 hours. Gemcitabine alone induced 35.3% cell death, and co-treatment with gemcitabine and Z-VAD-fmk induced 15.1% apoptotic cell death. Our results demonstrated that Z-VAD-fmk as a pan-caspase did not completely block the gemcitabine-induced apoptosis. Western blotting analysis showed that gemcitabine increased caspase-3, active caspase-8, p21 and p53 protein expressions in A549. Co-treatment with Z-VAD-fmk completely blocked caspase-3 and active caspase-8 protein expressions, but did not change the level of p21 and p53 protein expressions. Our data indicate that gemcitabine induced apoptosis through caspase-dependent and -independent pathways in A549.

Characteristics of Yeast Flora and Gas Generation during Fermentation of Doenjang (된장의 발효숙성에 관여하는 효모의 분포와 가스발생 특성)

  • Oh, Nam-Soon;Lee, Nam-Suk
    • Applied Biological Chemistry
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    • v.39 no.4
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    • pp.255-259
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    • 1996
  • In order to improve the quality of commercially manufactured Doenjang, yeast florae, gas and alcohol formation during fermentation of Doenjang were periodically examined. Candida rugosa, Candida zeylanoides, Pichia farinosa Saccharomyces cerevisiae and Zygosaccharomyces rouxii were isolated and identified from Doenjang at various fermentation stage. S. cerevisiae and Z. rouxii showed distintive gas and alcohol formation activities and the distribution ratio of Z. rouxii was 26% at 14 days and 76% as prevailed yeast strain after 30 days fermentation, respectively. Ethanol content of Doenjang was gradually increased into 2.19% at final stage of fermentation. The amount of gas generated during fermentation was 9.75 ml/g after 14 days, 4.5 ml/g after 30 days and decreased into negligible amount after 45 days fermentation. These inhibitory effects on gas generation by fermentation period would be ascribed to the ethanol Produced for fermentation. This results suggest that gas generation in commercially manufactured Doenjang could be eliminated through the effective control of fermentation by yeast without application of any preservatives.

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Fish Fauna and Community in Cheongpyeong Reservoir (청평호의 어류상 및 어류군집)

  • Choi, Jae-Seok
    • Korean Journal of Ecology and Environment
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    • v.38 no.1 s.110
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    • pp.63-72
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    • 2005
  • The fish fauna and community structure were investigated in the Lake Cheongpyeong, Korea, from August 2003 to April 2004. During the period, 43 species belonging 10 families were collected. There were 18 Korean endemic species 41.9%. The five dominant species numerically were A. gracilis (17.4%), Zacco platypus (14.6%), A. yamatsutae (13.2%), Hemibarbus labeo (11.9%), Rhinogobius brunneus (11.7%), and Zacco temmicki (3.0%). The five dominant species in biomass were Erythroculter erythropterus (15.07 kg), H. labeo (13.21 kg), Carassius cuvieri (6.47 kg), A. gracilis (6.05 kg), and Z. platypus (4.71 kg). Of 6 exotic fishes in the lake C. cuvieri, Lepomis macrochirus and Micropterus salmoides were originated from foreign countries but Anguilla japonica, Tridentiger brevispinis, and Chaenogobius urotaenius were introduced from other watershed in Korea.

Proline Accumulation and P5CS ($\Delta^1$-pyrroline-5-carboxylate synthetase) Gene Expression in Response to Salt Stress in Zoysiagrasses

  • Lee, Dong-Joon;Hwang, Cheol-Ho
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.48 no.1
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    • pp.20-24
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    • 2003
  • Proline is known as an osmotrotectant to enhance tolerance against both salt and dehydration stresses. A P5CS ($\Delta^1$-pyrroline-5-carboxylate synthetase) plays a major role in regulation of synthesis of proline. An overexpression of the mothbean P5CS gene in transgenic tobacco plant increased the levels of proline and osmotolerance. In an attempt to look for the possibility to use content of proline as well as a level of P5CS gene expression as molecular markers for salt tolerance, the amounts of proline and transcript levels of P5CS were measured as functions of either concentration of NaCl or length of treatment period among different species of zoysiagrass. Hybridzoysia showed the highest level of proline ($329\mu\textrm{g}$/g.f.w.) among five different species of zoysiagrass at 250 mM NaCl in 24 hours. The level of P5CS transcript was also the highest in the hybridzoysia at 250 mM NaCl in 24 hours. The transcriptions of P5CS gene were induced at the rates of 1.2, 1.2, 1.8, and 1.8, upon treatment of 250 mM NaCl in Z. japonica, Z. matrella, Z. sinica and hybridzoysia respectively. Based on a correlation between the level of P5CS transcript and the proline content among different species of zoysiagrass, a comparative structural analysis of the gene for P5CS from either Z. sinica or hybridzoysia may lead to an understanding of mechanism for salt tolerance shown differently among zoysiagrasses.

Effect of the Simulation-based Cooperation Program on Self-efficacy, Social problem-solving ability, and College life adjustment of Health College Students (시뮬레이션 기반 연합프로그램이 보건계열 대학생의 자기효능감, 사회적 문제해결 및 대학생활 적응에 미치는 효과)

  • Oh, Eun-Young;Choi, Ye-Sook
    • Journal of Digital Convergence
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    • v.16 no.10
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    • pp.301-311
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    • 2018
  • Purpose: The purpose of this study was to examine the effects of the simulation-based cooperation program on self-efficacy, social problem-solving ability and college life adjustment of health college students. Methods: A nonequivalent control group pre-posttest design was used. Sixty-eight students were in the experimental group receiving the simulation-based cooperation program, and 68 were in the control group with no treatment. Results: There were significant increases in self-efficacy(z=-4.70, p<.001) and college life adjustment(t=2.03, p<.05) in the experimental group compared to the control group. However, there was no difference in the social problem-solving ability (z=-1.87, p=.061) between the experimental and control groups. Conclusion: The findings indicate that the simulation-based cooperation program has a significant effect on improving self-efficacy and college life adjustment in health college students. Thus the simulation-based cooperation program to promote the social problem-solving ability needs to be more developed and research related with cooperation program is further needed.

Size Effect of Concrete Compressive Strength Considering Dried Unit Weight of Concrete (콘크리트의 기건단위질량을 고려한 콘크리트 압축강도의 크기효과)

  • Sim, Jae-Il;Yang, Keun-Hyeok;Yi, Seong-Tae
    • Journal of the Korea Concrete Institute
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    • v.27 no.2
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    • pp.169-176
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    • 2015
  • Since the size effect law announced currently has been based on the normal weight concrete, for light weight concrete having different fracture characteristics, its application is questionable. Accordingly, in this study, a model equation to predict the effect of dried unit weight of the concrete on size effect of its compressive strength was developed and a database using existing research results was created. After determining the experimental constants of prediction models of Ba${\check{z}}$ant based on nonlinear fracture mechanics, Kim and Eo, and this study using the database, their results are mutually compared. Finally, it was found that the prediction model of this study considered dried unit weight of concrete predicted well the test results for light weight concrete than that of the models of Ba${\check{z}}$ant and Kim and Eo.

A Study on the Effects of ET Training for the Development of Interpersonal Relationship and Self-Identity (인간관계 효율성 훈련이 간호대학생의 인간관계와 자아정체감에 미치는 효과)

  • Yoon, Yean-Hee;Koh, Myung-Suk
    • Journal of Korean Academy of Nursing Administration
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    • v.10 no.3
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    • pp.291-298
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    • 2004
  • Purpose: This study is to investigate if the effectiveness training program, suggested by Gordon(1970), could help these nursing students with the problems of interpersonal relationship and self-identification. Method: This study was designed using nonequivalent control group protest-posttest design. The subject for this study were thirty nursing students. Fifteen nursing students of the experimental group experienced the Effectiveness Training for 8 weeks (3 hours/week). The effect of Effectiveness Training was measured using Relationship Change Scale devised by Lee, H.D. & Moon, S.M.(1979) and Ego Identity Scale devised by Dignan(1965) which was translated by Seo, B.Y.(1975) Pretest data were collected by the researcher from both experimental and control group before training. After the end of eight weeks training, posttest data collected from both experimental and control group. Samples were analyzed using SPSS PC+. Result: 1. The first hypothesis, "level of interpersonal relationship of the experiment group after 8 weeks will be significantly higher than that of the control group"(z=-1.965, p=.049)was supported. 2. The second hypothesis, "level of ego-identity of the experimental group after 8 weeks will be significantly higher than that of the control group"(z=-2.191, p=.028)was supported. 3. The third hypothesis, "level of interpersonal relationship of the experiment group will be significantly higher than that of the control group after 4 months of training"(z=-.634, p=.238)was not supported. 4. The fourth hypothesis, "level of ego-identity of the experimental group will be significantly higher than that of the control group after 4 months of training"(z=-.292, p=.642)was not supported. Conclusion: The Effectiveness Training can be considered as an effective method of nursing students's interpersonal relationship & ego-identity, because it was proved to help nursing students increase level of their interpersonal relationship & ego-identity but it was needed to reinforce for continuing of the effect of the interpersonal relationship & ego-identity.

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Development of New Hybrid Cultivar 'Senock' in Zoysiagrass (한국잔디 신품종 '세녹(Senock)' 개발)

  • Choi Soon Soo;Yang Geun Mo
    • Asian Journal of Turfgrass Science
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    • v.18 no.4
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    • pp.201-209
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    • 2004
  • This study was carried out to develope new zoysiagrass cultivar 'Senock' (Patent registration: 10-2003-0072018). Artificial crossing between collected lines of Z. sinica and Z. matrella (collected in South Korea) was conducted to develope F1 plant (CSM) which was cultivated at field for open self-pollination. Among the open pollinated progenies, CSM8 (Senock) showed superior performance in color and density rating. 'Senock' showed genetically dark green color, with medium leaf width ($3.1\pm0.17mm$), low plant height ($14\pm5.67cm$), and wide leaf angle ($67.3\pm11.1degree$). Height to the lowest leaf blade of this cultivar was $2.0\pm0.14cm$, which may allow low mowing height. Specific bands with primer number OPB7 by RAPD analysis can be used for cultivar identification.