• Asian-Australasian Journal of Animal Sciences
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• v.16 no.11
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• pp.1673-1679
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• 2003

Two hundred forty 1-d-old Arbor Acres broiler chicks were used to investigate the effects of Cu (II)-exchanged montmorillonite (CEM) or montmorillonite on the growth performance, intestinal microflora, bacterial enzyme activities and morphology of broilers. The chicks were assigned randomly into three groups with 80 chicks per treatment. The three dietary treatments were basal diet only (control group), basal diet +1 g $kg^{-1}$ montmorillonite, and basal diet +1 g $kg^{-1}$ CEM. The results showed that the addition of CEM to the diet increased significantly the body weight and feed efficiency, but a similarly significant increase was not found in broilers fed the diet containing montmorillonite. Supplementing the CEM in the diet of broilers also decreased the numbers of Clostridium perfringens and Escherichia coli in the small intestine and cecum. The addition of either CEM or montmorillonite to the diet depressed the activities of $\beta$-glucosidase and $\beta$-glucuronidase in the small intestinal and cecal contents. Data of villus height and crypt depth for duodenum, jejunum and ileum indicated that dietary addition of CEM or montmorillonite improved the small intestinal mucosal morphology.

• Journal of Korea Technology Innovation Society
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• v.10 no.3
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• pp.431-457
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• 2007

The main purpose of this study is to analyze the determinants of innovation in the medium core firms that belong to components and materials industry. For this purpose, we introduce the Schumpeterian hypothesis as a theoretical background at first. According to the Schumpeterian hypothesis, large firms in concentrated markets are likely to have more innovative activities. That means, firm site and market structure are the main determinant of innovation. Then, we propose other economic factors that have been considered to have effects on firms' innovative activities in previous studies. Those factors are export, profit, growth rate, R&D expenditure and capital intensity. In order to analyze the determinants of innovation, we estimate whether firm size, market structure, export, profit, growth rate, R&D expenditure and capital intensity affect to the possibility of creating innovation in medium core firms. In order to do this, our study uses survey data from 'Korean Innovation Survey(2005)' conducted by STEPI as well as utilizes the probit model as an analytical method. According to the empirical results, firm size has a positive relationship with innovative activities of medium core firms but market concentration does not. We find the negative correlation between market concentration and innovative activities in this study. Thus, was have to say that we do not fully support the Schumpeterian hypothesis in this case. Among other variables, profit and R&D expenditure are estimated to have positive relationship with innovative activities, while export and capital intensity are estimated to have negative relationship with innovative activities. In case of growth rate, we do not find any significant relationship with innovative activities. In conclusion, larger firm size, higher market competition, more access to the financial market and additional R&D investment would facilitate innovative activities of medium core firms. However, we have to review the relationship between export and innovative activities that has been estimated in this study. While the estimated effect of export on innovative activities can be explained by the own characteristics of medium core firms that produce and supply capital goods to final manufacturer, we have address this issue in the future.

• BMB Reports
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• v.29 no.6
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• pp.549-554
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• 1996

Phosphoinositide turnover in response to platelet-derived growth factor, epidermal growth factor, and bradykinin was evaluated in NIH 3T3 cells. Platelet-derived growth factor and bradykinin induced a significant increase in incorporation of $^{32}P$ into phosphatidylinositol (PI), phosphatidylinositol 4-monophosphate (PIP), and phosphatidylinositol 4.5-bisphosphate ($PIP_2$) in serum-starved NIH 3T3 cells. However, epidermal growth factor increased incorporation of $^{32}P$ into these phosphoinositides by only a small amount. Stimulation with platelet-derived growth factor, not bradykinin, caused a rapid elevation of PI and PIP kinase activities that were maximally activated within 10 min. The maximal levels of their elevation in cells with plateletderived growth factor stimulation were 3.2-fold for PI kinase, and 2.1-fold for PIP kinase. Short term pretreatment of NIH 3T3 cells with phorbol 12-myristate 13-acetate, activator of protein kinase C. caused an approximately 60% decrease in platelet-derived growth factor-induced PI kinase activities, indicating the feedback regulation of phosphoinositide turnover by protein kinase C. These results suggest that although the enhancement of phosphoinositide turnover is a rapidly occurring response in platelet-derived growth factor- or bradykinin-stimulated NIH 3T3 cells, phosphoinositide kinases may be associated with initial signal transduction pathway relevant to platelet-derived growth factor but not to bradykinin.

• Korean Journal of Microbiology
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• v.23 no.2
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• pp.147-156
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• 1985

Seasonal and vertical variations of abiontic soil carboxymethylcellulase (CMCase) activities were assessed every other month for a year in two contrasting forest soils and evaluated the relationships between soil CMCase activity and environmental parameters. In climax deciduous soil, variations in CMCase activities caused by differences in sampling time were greater than those caused by differences in soil depth. On the other hand, counter phenomenon was obserned in coniferous soil at the stage of development. Correlation analyses showed that soil CMCase activities were significantly (p>0.01) correlated with microbial respiration rates ($O_2$ uptake) and all of the microbial population sizes. From these results, it is suggested that determination of abiontic soil CMCase activity is an useful additional index for evaluating the overall microbial growth and activity in soils.

• Korean Journal of Microbiology
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• v.22 no.2
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• pp.91-96
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• 1984

The changes in the activities of Cellulase and Xylanase of A. phoencis during the life cycle were surveyed by using synchronized culture technique. Avicelase activity of the fungus was reached at peak in the initial hyphal growth stage, but decreased gradually during the conidiophore formation, vesicle-phialide formation, and sporulation stages in decreasing order. CMCase, Salicinase, and Xylanase activities were raised very high in the initial hyphal growth stage, but decreased gradually in conidiophore formation and vesicle-phialide formation stages, and then increased, more or less, in the sporulation stage.

• Korean Journal of Medicinal Crop Science
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• v.28 no.4
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• pp.254-259
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• 2020

Background: Centella asiatica is a well-known medicinal plant having a wound healing effect. In this study, the growth, asiaticoside content, and antioxidant components and activity were investigated in C. asiatica resources under different cultivation and irrigation conditions. Methods and Results: The cultivation and irrigation methods were divided as greenhouse and open field, and sprinkler and sub irrigation. respectively. Growth characteristics were measured in aerial parts of C. asiatica. Asiaticoside content was analyzed using high performance liquid chromatography. Total polyphenol, total flavonoid and 2,2-diphenyl-1picryl hydrazyl (DPPH) radical scavenging activity were analyzed for antioxidant activities. Growth was higher under greenhouse and sub irrigation than open field and sprinkler conditions. In the leaves, asiaticoside content was 53.45 mg/g (open field) and 34.38 mg/g (sub irrigation), total polyphenol was 41.14 mg/g (open field) and 25.73 mg/g (sub-irrigation), and total flavonoid was 27.26 mg/g (open field) and 23.72 mg/g (sub-irrigation). DPPH radical scavenging activity in the leaves was 85.97 mg·ascorbic acid equivalent (AAE)/g (open field) and 54.83 mg·AAE/g (sub irrigation). Conclusions: Asiaticoside and antioxidant components and activity were not accompanied with high yield, although high growth was observed under greenhouse conditions. Therefore, cultural requirements of C. asiatica should be sufficiently considered to suit each purpose.

• Food Science of Animal Resources
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• v.30 no.6
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• pp.946-950
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• 2010

This study evaluated the antimicrobial effects of meat processing-related organic acids on Burkholderia thailandensis (Burkholderia pseudomallei surrogate) with different water activities. B. thailandensis KACC12027 (4 log CFU/mL) was inoculated in microwell plates containing tryptic soy broth pH-adjusted to 4, 5, 6, and 7 with ascorbic acid, citric acid, and lactic acid and with water activities adjusted to 0.94, 0.96, 0.98, and 1.0 with NaCl, followed by incubation at $35^{\circ}C$ for 30 h. The optical density (OD) of the samples was measured at 0, 3, 6, 12, 24, and 30 h at 595 nm to estimate the growth of B. thailandensis. Growth of B. thailandensis was observed only at water activity of 1.0. In general, more bacterial growth (p<0.05) was observed at pH 6 than at pH 7, and the antimicrobial effects of the organic acids on B. thailandensis were in the following order: Ascorbic acid > lactic acid > citric acid after incubation at $35^{\circ}C$ for 30 h. These results indicate that organic acids in meat processing-related formulations should be useful in decreasing the risk related to an emerging high risk agent (B. pseudomallei).

• Ecology and Resilient Infrastructure
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• v.5 no.2
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• pp.82-87
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• 2018

Proliferation of algae on the surface of concrete or mortar in aquatic habitat has a negative impact on maintenance of concrete-based structures. Growth of algae may decrease stability of structure by bio-deterioration. In this study, we developed a functional mortar for restraining bio-deterioration by using $Cu^{2+}$ ion. The mortar contains soluble glass beads made of $Cu^{2+}$ ion, which can dissolve into water slowly. Mortars prepared with different ratio of glass beads (0, 2, 5, 10, and 15%) were placed in a culture medium with algae and incubated over a month period. Water chemistry, chlorophyll-a, and extracellular enzyme activities were measured. The incubation was conducted in both freshwater and seawater conditions, to assess applicability to both aquatic conditions. Overall, mortar with Cu glass exhibited lower chlorophyll-a content, suggesting that the functional mortar reduced algal growth. DOC concentration increased because debris of dead algae increased. Cu glass also decreased phosphatase activity, which is involved in the regeneration of inorganic P from organic moieties. Since, P is often a limiting nutrient for algal production, algal growth may be inhibited. Activities of ${\beta}$-glucosidase and N-acetylglucosaminidase were not significantly affected because carbon and nitrogen mineralization may not be influenced by the Cu glass beads. Our study suggests that functional mortar with Cu glass beads may reduce the growth of algae on the surface, while it has little environmental impact.

• Mycobiology
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• v.37 no.1
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• pp.48-52
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• 2009

Essential oils are mixtures of volatile, lipophilic compounds originating from plants. Some essential oils have useful biological activities including antimicrobial, spasmolytic, antiplasmodial, and insect-repelling activities. In this study, we tested the antimicrobial activity of essential oil prepared from the aromatic plant, Cymbopogon citrates, against three important plant pathogenic and medical microorganisms, Pectobacterium carotovorum, Colletotrichum gloeosporioides, and Aspergillus niger. It effectively inhibited the growth of the bacterium, Pectobacterium carotovorum, in a dose-dependent fashion, and 0.5% of the oil inhibited the growth of bacteria completely. Similarly, the essential oil inhibited the growth of plant pathogenic fungus, Colletotrichum gloeosporioides, and the addition of 1% of essential oil completely inhibited the growth of fungus even after 5 days of culture. Finally, it effectively inhibited the growth of the medically and industrially important fungal species, Aspergillus spp. These results suggest that the essential oil from Cymbopogon citrates may be an environmentally safe alternative to inhibit antimicrobial agents for various uses.

• Journal of Sericultural and Entomological Science
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• v.20 no.1
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• pp.5-10
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• 1978

The effects of foliar spray of Kinetin (6-Furfurylaminopurine) on the growth of mulberry tree and the metabolic activities in the leaves were measured. The results of this experimented are summarized as follows: 1. Foliar application of Kinetin was effective in increasing of leaf area, the fresh and dry weight of the leaves, the length and diameter of shoots. 2. Chlorophyll content was generally increased in all treated leaves. 3. All the treated leaves were higher in GOT activity than the control leaves but were lower in GPT activities. 4. The activities of the carbohydrate metabolism in the mulberry leaves were higher than that of the control in all treated leaves.