• Journal of Ginseng Research
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• v.26 no.3
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• pp.151-158
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• 2002

Ginseng (Panax quinquefolius L.) has become one of the most valuable herb crops grown in North America. However, traditional cropping practices are favourable to disease and significant losses due to root disease are common, despite frequent use of fungicides. Seedlots are often contaminated with pathogens, however, little is known about the causes of seed decay and the role of seed pathogens as incitants of root rots. It was shown that both Fusarium spp. and Cylindrocarpon destructans were able to rot seeds and that C. destructans was more virulent than Fusarium spp. on seedling roots. A modified rose bengal agar MRBA) medium (1 g KH$_2$PO$_4$; 0.5 g MgSO$_4$; 50 mg rose bengal; 10 g dextrose; 5 g Bacto peptone; 15 g Bacto agar; 30 mg streptomycin sulfate; 250 mg ampicillin; 10 mg rifampicin; 500mg pentachloronitrobenzene; 500 mg dicloran; and 1 L distilled water) was superior to potato dextrose agar in detecting C. destuctans in diseased roots. Isolation of C. destructans from diseased seedlings arising from seeds sown in replant soil supported the hypothesis that this pathogen is a cause of ginseng replant failure in North America.

• Korean Journal of Microbiology
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• v.25 no.1
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• pp.17-22
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• 1987

For the purpose of securing of strains which can be usefully utilized to study symbiosis between Rhizobium and legume plant, A. tumefaciens T7 was isolated and characterized and then subgroup biovar was determined. A. tumefaciens T7 induced smooth tumor like nopaline type one and did not grow at $37^{\circ}C$ and in the presence of 2% NaCl on yeast extract mannitol medium. The strain was able to grow on the New and Kerr selective media and utilize erythritol but not phenylalanine, tryptophan, and tartarate as a sole carbon source. Negative results were obtained from 3-keto-lactose production and oxidase test. The strain produced alkalifrom malonate and citrate and showed acid litmus milk reaction At least two large plasmids were detected in the cell lysate. According to all of these results, it could be concluded that subdivision of isolated strain was biovar 2.

• Journal of Microbiology
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• v.45 no.3
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• pp.213-218
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• 2007

Trametes versicolor has a lignin degrading enzyme system, which is also involved in the degradation of diverse recalcitrant compounds. Manganese-dependent peroxidase (MnP) is one of the lignin degrading enzymes in T. versicolor. In this study, a cDNA clone of a putative MnP-coding gene was cloned and transferred into an expression vector (pBARGPE1) carrying a phosphinothricin resistance gene (bar) as a selectable marker to yield the expression vector, pBARTvMnP2. Transformants were generated through genetic transformation using pBARTvMnP2. The genomic integration of the MnP clone was confirmed by PCR with bar-specific primers. One transformant showed higher enzyme activity than the recipient strain did, and was genetically stable even after 10 consecutive transfers on non-selective medium.

• Journal of Microbiology and Biotechnology
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• v.7 no.1
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• pp.25-31
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• 1997

Protoplast fusion between L. casei KCTC 1121 and L. acidophilus 88 was attempted to obtain improved strains. The fusants produced a bacteriocin against indicator strains, making a smaller inhibition zone compared to that of L. acidophilus 88. After culturing for 2 months on selective medium, the selected fusants were still stable without segregation. Fusants showed higher lipase activity compared to those of the two parent strains. Fusant No.4, 11, and 15 exhibited excellent lactic acid productivity. Fusant No.4 and 15 exhibited improved proteolysis ability compared to the two parent strains. Whereas L. casei possessed both ${\beta}-galactosidase$ and $phospho-{\beta}-galactosidase$ activities, and L. acidophilus 88 had only ${\beta}-galactosidase$ activity, the fusants had both the intermediate enzyme activities. Cell size of the fusants was greater than that of the parents.

• Nuclear Engineering and Technology
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• v.55 no.8
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• pp.2734-2741
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• 2023

Brachytherapy is a special case of radiotherapy. It should be arranged according to some principles in medical radiation applications and radiation physics. The primary principle is to use as low as reasonably achievable dose in all ionizing radiation applications for diagnostic and therapeutic treatments. Dosimetric distributions are dependent on radioactive source properties and radiation-matter interactions in an absorber medium such as phantom or tissue. In this consideration, the geometrical structure and material of the seed capsule, which surrounds a radioactive material, are directly responsible for isodose profiles and dosimetric functions. In this study, the radiometric properties of capsule material were investigated on dose distribution in a water phantom by changing its nuclear properties using the EGSnrc Monte Carlo (MC) simulation code. Effective atomic numbers of hypothetic mixtures were calculated by using different elements with several fractions for capsule material. Model 6711 brachytherapy seed was modeled by EGSnrc/Dosrcnrc Code and dosimetric functions were calculated. As a result, dosimetric parameters of hypothetic sources have been acquired in large-scale atomic number. Dosimetric deviations between the data of hypothetic seeds and the original one were analyzed. Unit dose (Gy/Particle) distributions belonging to different types of material in seed capsule have remarkably differed from the original capsule's data. Capsule type is major variable to manage the expected dose profile and isodose distribution around a seed. This study shows us systematically varied scale of material type (cross section or effective atomic number dependent) offers selective material usage in production of seed capsules for the expected isodose profile of a specific source.

• Korean Business Review
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• v.19 no.1
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• pp.53-80
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• 2006

This research has been accomplished to build up the growth strategies of Kangwon district's small & medium-sized construction firms. For this purpose, we made an investigation of the present situation and status for existing regional small & medium construction firms by analyzing data. Based on the results from this study, the following growth strategies are suggested to gain their competitive advantages. Firstly, most of all, the role of the top manager is the most important factor since most of the top manager for the small & medium-sized construction firms coincide with the owner the firms. Secondly, the specialization strategy is to establish. Above all they concentrate their business capacities on core business. Then, this growth strategy should be based on the selective escalation of functions in order to maintain an appropriate level of construction works. Thirdly, the specialized skills and skilled workers are ensured for competitive advantages. For human resource development, they should train workers to be multi-functioned on the assumption the they could stay at firm until they wish to retire. Finally, the government must also spare no effort to encourage the small & medium-sized construction firms to build up it's competitive power and cultivate it's spontaneous generation power though the reformation of system related whit the small and medium construction industry.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.8
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• pp.992-997
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• 2008

In this study, we investigated the indirect effect of silk-fibroin on osteoclastic differentiation of RAW264.7 cells. The conditioned medium were collected from MC3T3-E1 osbeoblasts treated with $0.001\;mg/mL{\sim}0.1\;mg/mL$ silk fibroin for 6 days, mixed in 1:1 ratio with osteoclast medium, and then added into RAW264.7 cells with receptor activator of nuclear factor kappa B ligand (RANKL), a differentiation inducer for 3 days. Of osteoclastic cytokines in the conditioned medium, the protein expression of osteoprotegerin (OPG) with silk-fibroin was not significantly different. However, the protein expression of interleukin (IL)-$1{\beta}$ was specifically lower in a dose dependent manner. In RAW264.7 cells, the conditioned medium with silk-fibroin inhibited RANKL induced osteoclastic differentiation as total number of multinucleated tartrate-resistant alkaline phosphatase (TRAP)-positive osteoclasts in a dose dependent manner. Taken together, we demonstrated that the conditioned medium of silk-fibroin treated osteoblasts inhibits RANKL induced differentiation of osteoclasts with inhibiting selective expression of IL-$1{\beta}$.

• Korean Journal of Environmental Agriculture
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• v.17 no.3
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• pp.279-285
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• 1998

Fenitrothion-degrading microorganisms were isolated from 124 sampling sites of paddy, upland, forest and polluted soil, and wastewater. A total of 1,071 strains were isolated from each selective medium supplemented with 50mg/l of fenitrothion - nutrient agar (NA) 601, potato dextrose agar (PDA) 201, Actinomycetes isolation agar (AIA) 168 and basal salt medium (BSM) 101, respectively. Twenty-eight effective strains of them, which showed more than 80% degradation of fenitrothion by the gasliquid chromatography(GLC) analysis. were successfully selected from each liquid culture supplemented with 50mg/l of fenitrothion - NB 12(upland soil 3, paddy soil 3, forest soil 2, polluted soil 4), PDB 8(upland soil 1, paddy soil 2, forest soil 2, polluted soil 3) and PSB 8(upland soil 1, forest soil 1, polluted soil 6), respectively. Four strains - NPal, NFol, PFol and BPol, which have the most powerful degradation activity were finally selected among 28 fenitrothion-degrading microorganisms based on the degradation rate at the concentration of 100mg/l fenitrothion in enrichment media.

• Journal of Korean Society of Forest Science
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• v.77 no.2
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• pp.199-207
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• 1988

Three clones of Populus alba ${\times}$ P. grandidentata have been tested for susceptibility to Agrobacterium tumefaciens strains A281 and A348. We determined the optimum concentration of kanamycin sulfate for effective selection of leaf disc-derived, transgenic tissues transformed using Agrobacterium binary vector pGA472 containing a neomycin phosphotransferase gene (NPT-II) which confers kanamycin resistance. Of the wild type Ti plasmids contained by the two Agrobacterium strains, pTiBo542 of strain A281 appears to be best suited to serve as a helper plasmid for binary vector systems. A relatively low concentration (10mg/l) of kanamycin sulfate inhibited adventitious shoot initiation from leaf discs on regeneration medium. Transformed kanamycin-resistant calli were obtained by culturing Agrobacterium inoculated leaf discs on selective regeneration medium. The transformed kanamycin-resistant calli continued to grow on regeneration media supplemented with kanamycin sulfate to levels of 50 and 200mg/l. The growth of non-co-cultivated control calli was severely inhibited on regeneration medium containing 50mg/l kanamycin sulfate.

• The Journal of Society for e-Business Studies
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• v.25 no.4
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• pp.15-32
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• 2020

Increasing uncertainties in the technological innovation environment and increasing technology competition also present new challenges in terms of industrial technology security. Therefore, the purpose of this study was to identify the direction of policy change necessary for the improvement of related policies in the future by examining the importance and implementation of the government's industrial technology security support policies for small and medium-sized enterprises engaged in industrial technology innovation activities. As a result of the analysis, first of all, small and medium-sized enterprises that responded to the government's industrial technology security support policy were perceived to be less performing than the importance of the program. These results can be said to mean that selective budget expansion for related policy programs may be necessary, along with efforts to improve the quality of each program. Second, an analysis of the differences in group recognition between new technology certification firms and industrial technology verification(certification) companies showed that significant differences exist between groups for the program. These results suggest that more effective operation of the relevant policies may require policy enforcement in consideration of the level of security and will of each company in industrial technology, as much as the quantitative characteristics of the entity. This study is meaningful in providing the necessary policy directional basic information for the design and execution of more specific and effective industrial technology security policies by presenting empirical research results that domestic small and medium-sized enterprises are aware of about the government's industrial technology security policies.