• 한국약용작물학회지
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• 제25권6호
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• pp.375-380
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• 2017

Background: The objective of this study were to determine the antibacterial activity and antibiotic activity-enhancing effect of 70% ethanol extract of the root of Rumex japonicus Houtt. and its fractions when used in combination with gentamicin against aerobic skin flora. Methods and Results: The antibacterial activity and antibiotic (gentamicin) activity enhancing effect against aerobic skin flora were determined using the disc diffusion assay. Chloroform fraction (CF) and ethyl acetate fraction (EF) showed higher activities against Staphylococcus aureus and Staphylococcus epidermidis than those shown by other fractions. Regarding the antibiotic (gentamicin) activity-enhancing effect against aerobic skin flora, the n-hexane fraction (HF) and CF showed strong activity. The combination of HF and CF with gentamicin was evaluated using the broth dilution assay to determine the inhibitory effect on the growth of aerobic skin flora. The combination of CF with gentamicin exhibited the highest inhibitory effect on the growth of S. aureus and S. epdermidis. MTT assay performed to determine the viability of L929 cells revealed that EF treatment resulted in viability of 33.96 - 116.76% at the tested concentration. The combination of 70% ethanol extract and its other fractions with gentamicin showed low cell toxicity. Conclusions: Appropriate use of antimicrobial agents is important prior to the development of new antibiotics. The 70% ethanol extract of the root of R. japonicus Houtt. and its fractions showed significant synergism with gentamicin when used in combination against S. aureus and S. epdermidis. Thus, R. japonicus Houtt. could be used as a functional materials in antimicrobial-related fields.

• The Korean Journal of Ecology
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• 제21권3호
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• pp.251-255
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• 1998

To elucidate the effects of a hydroelectric dam construction on annual ring growth of Pinus densiflora, the annual ring widths of 68 trees collected from 7 sites were closely examined. The result was analyzed to ask three special questions first, whether there are real effects of dam construction on the radial growth second, would the magnitude of the effect be different due to two periods of under-construction and post-construction the last, would it be different among age classes. Annual ring growth has been significantly enhanced by the dam construction. Specially, its effect was marked after the construction was finished and the reservoir was filled up with water. There was, however, no remarkable evidence that pine growth would be reduced while the dam was under construction, even though there was a minor decreasing trend. The magnitude of the effect was different among age groups. That is, the changed condition after the construction enhanced relatively the growth of aged trees monre. According to other meterological research since the dam was constructed, the reasons of enhancing pine growth assumed to be the increase of daily temperature, the decreased of daily temperature difference and the increased of rainy days.

• 환경생물
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• 제34권3호
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• pp.161-168
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• 2016

본 연구에서는 엽록소 형광반응 (OJIP)분석을 통해 고추재배에서 폐달걀 분해 액비의 생육증진효과에 대하여 평가하였다. 고추재배 전기간을 통하여 고추의 생장은 통계학적으로 유의성을 보이지는 않았으나, 폐달걀 분해 액비를 처리한 실험구에서 좋은 생육을 보였다. 엽록소 형광반응 실험 시작한 후 무처리구의 엽록소 형광량이 분해 액비의 형광량보다 커서 분해 액비 처리구의 광이용 효율이 더 좋았음을 알 수 있었다. 이는 결국 광합성량의 증가로 이어질 것으로 판단된다. 광화학 매개변수 중 Fo, ABS/RC, RC/ABS, TRo/RC, $DI_0$/RC, $\text{DF_{TOTAL ABS}}$ 등 6개 parameter가 광화학 반응의 효율을 나타내는 중요한 요인으로 판단되었다.

• Journal of Ecology and Environment
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• 제29권4호
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• pp.337-342
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• 2006

The total monoterpenoid content of the pine litter layer and the availability of these compounds as inhibitors/stimulators on Polysphondylium violaceum of cellular slime molds were investigated. In order to determine the several monoterpenoids in the natural environment, we examined their concentrations in fresh, senescent, and decaying needles from 3 pine species (Pinus densiflora, P. thunbergii, P. rigida) by litter bag method. Total monoterpenoid content was highest in the fresh needles, but also remained relatively high in senescent needles. The effect of monoterpenoids identified from Pinus plants on the growth of P. violaceum was studied. We tested four concentrations (1, 0.1, 0.01, and $0.001\;{\mu}g/{\mu}L$) of each compound by using a disk volatilization technique. Each compound was treated after germination of spores of P. violaceum. All of the compounds at $1\;{\mu}g/{\mu}L$ concentration had a very strong inhibitory effect on cell growth of P. violaceum. Fenchone at all concentrations, myrcene, verbenone, bornyl acetate, and limonene at low concentrations stimulated the growth of P. violaceum. These results suggest that inhibitory or enhancing effects of selected monoterpenoids depend upon the concentration of the individual compound.

• 한국식물병리학회지
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• 제11권4호
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• pp.292-297
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• 1995

We developed an in vitro assay method for evaluating plant growth promotion and providing an evidence that the growth promotion is rendered by growth enhancing factors. The amendment of culture filtrates of Trichoderma harzianum T95 and Gliocladium virens G872 and G872B in Murashige and Skoog (MS) agar medium enhanced the cotyledon growth of cucumber in terms of fresh weight and primary leaf area of cucumber cotyledon cuttings, of which the treatment of G. virens G872B was the most effective. The mycelial culture filtrate of G872B was more effective in the growth promotion than its conidial germling filtrate. The addition of 1% sucrose in MS mineral medium with 0.1% culture filtrates of the antagonists (T95 and G872B) was optimum for enhancing the effect of the filtrates on the growth of cotyledon cuttings in vitro. When cucumber seeds treated with G872B, Pseudomonas putida Pf3 or the G872B-Pf3 mixture were planted in a greenhouse, the rate of seed germination, biomass of shoot and root, and yield of cucumber fruits were increased, especially by G872B or the G872B-Pf3 mixture. Correspondingly, cucumber fruit yields in early to middle-cycles of harvest were significantly greater in the plots of G872B than the control and Pf3-treated plots, and the final yield was highest in the plots of the G872B-Pf3 mixture applications.

• Journal of Microbiology and Biotechnology
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• 제17권6호
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• pp.1036-1040
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• 2007

Sodium butyrate (NaBu) has been used to enhance protein expression levels in mammalian cell culture. To determine the clonal variability of recombinant Chinese hamster ovary (rCHO) cells in response to NaBu addition regarding specific antibody productivity $(q_{Ab})$, three rCHO clones were subjected to different concentrations of NaBu. For all three clones, NaBu addition inhibited cell growth and decreased cell viability in a dose-dependent manner. On the other hand, the enhancing effect of NaBu on $q_{Ab}$ varied significantly among the clones. NaBu addition enhanced the antibody production of only one clone. RT-PCR analysis revealed that the changes in $q_{Ab}$ correlated linearly with those of the mRNA transcription level. Thus, it was concluded that the different enhancing effects of NaBu on protein expression in rCHO cell clones resulted from their different mRNA transcription levels.

• Mycobiology
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• 제39권1호
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• pp.7-11
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• 2011

Shimizuomyces paradoxus showed no inhibitory effect against plant pathogen fungi, such as Fusarium oxysporum f. sp. lycopersici and Alternaria solani. The S. paradoxus culture filtrate showed higher seed germination and seedling growth rates in canola than distilled water and potato-dextrose broth. A conidial suspension of $1.0{\times}10^4/mL$ resulted in the highest growth stimulating effects on total plant length, and fresh and dry weight of shoots and roots in cucumber, when compared to the highest suspension concentration. Total plant length and shoot weight increased with the foliar spray treatment, and root length and root weight increased by simultaneous treatments of soil drenching and foliar spray in cucumber. Lower concentrations of the S. paradoxus conidial suspension increased the harvest of tomato fruit.

• 기술혁신연구
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• 제22권1호
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• pp.23-58
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• 2014

본 연구는 규모가 작고 역동적인 벤처기업의 성장에 영향을 줄 수 있는 요인들 중에서 기업의 전략적 행동이나 경영자의 경영 역량과 관련된 제품 전략과 CEO(최고경영자) 특성의 효과를 실증적으로 분석하였다. 벤처기업의 표본을 이용하여 FGLS 추정법에 기반한 회귀분석의 결과에 따르면, 제품 전략과 CEO 특성은 기업 성장에 유의한 영향을 주며 추가적인 설명력을 가진다. 일반적으로 제품의 다양화와 마케팅을 강조할수록, 변화혁신을 완화할수록 성장률이 높았다. 그리고 CEO가 경영지배력을 가진 창업자가 아니거나, 현재 사업관련 분야에서 실무경험이 많을수록 성장률이 높았다. 또한, 연구개발 위주 업무경력보다 일반경영 중심의 업무경력을 가진 CEO가 관리하는 기업이 성장률이 더 높았다. 제품 전략과 CEO 특성이 벤처기업의 성장에 미치는 이런 효과들은 조직수명주기 단계에 따라서 달라졌다. 창업기 및 초기 성장기에 있는 기업에서 제품의 마케팅 강조 전략과 CEO의 일반경영 중심 업무경력이 기업 성장에 미치는 긍정적 효과가 상대적으로 강화된 반면, 성숙기 및 정체기에 있는 기업에서 이런 제품 전략과 CEO 특성이 기업 성장에 미치는 효과가 부정적이거나 유의하지 않았다.

• Asian-Australasian Journal of Animal Sciences
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• 제6권2호
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• pp.319-323
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• 1993

The effect of bovine growth hormone digested with trypsin on whole-body protein synthesis in vitro of chicken embryos was investigated by using a whole-embryo culture system. Bovine growth hormone at 5.3 and 530 ng/ml was digested partially and completely with trypsin for 4 min and 18 h, respectively. After culturing chicken embryos with a synthetic medium containing $L-[4-^3H]$ pheylalanine, whole-embryo protein synthesis was determined from the ratio of specific radioactivities of free and protein-bound pheylalanine. Whole-embryo protein synthesis of the control group cultured with no bovine growth hormone was $49.5{\pm}2.2%/d$. There was no significant interaction between digestion time and the concentration of trypsin-digested bovine growth hormone. Tryptic digestion of bovine growth hormone increased fractional synthesis rates of whole-body protein compared to the 0-min groups, and there was no significant difference between the 4-min and 18-h groups. The higher concentration (530 ng/ml) of trypsin-digested bovine growth hormone was more effective in enhancing whole-embryo protein synthesis than the lower concentration (5.3 ng/ml).

• KDI Journal of Economic Policy
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• 제39권4호
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• pp.25-50
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• 2017

Whereas a large variety of previous studies show mixed results regarding the relationship between public investment and economic outcome, several studies have been conducted on related issues in Korea. The present study deals with the effect of public investment in Korea on economic growth and productivity. Using administrative data, it exploits three different methodologies: the total factor productivity approach, production function approach, and stochastic frontier production function approach. The results of this study show that public investment has a statistically significant effect on economic growth. However, it contributes little to enhance productivity. It is explained that there exists inefficiency of production in the Korean economy. These findings indicate that public investment has played a central role in the direct input factor and not in indirect role in Korea. Thus, it is necessary for public investment policies to concentrate on enhancing the efficiency of the Korean economy.