• Korean Journal of Veterinary Research
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• v.49 no.4
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• pp.319-328
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• 2009

This study investigated the epidemiology of Listeria (L.) monocytogenes, a food-borne pathogen. The epidemiology of food-borne pathogens is of great importance for clarifying bacterial origin and preventing bacterial contamination and infection. This work examined 68 L. monocytogenes strains, including 11 reference strains and 57 isolates from imported US beef, domestic meats (beef, pork, chicken meat), raw milk, and milk plants. The random amplified polymorphic DNA (RAPD) techniques were optimized to develop a standard molecular epidemiological analysis of L. monocytogenes. There was great genetic variability among the isolates, which produced 24 and 34 RAPD patterns with primer HLWL85 and HLWL74, respectively. The discriminatory power of the RAPD methods with HLWL85 and HLWL74 primer were very high (DI = 0.957; S ${\geq}$ 80%, S ${\geq}$ 95%). Some RAPD types were specific to origin. A few RAPD types were specific for L. monocytogenes strains belonging to a particular serotype. Using the HLWL85 primer, the strains isolated from milk plants could be distinguished from the other strains. And using the HLWL74 primer, the strains isolated from imported beef (US) could be distinguished completely from the other strains.

• Nuclear Engineering and Technology
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• v.33 no.5
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• pp.468-482
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• 2001

As a process of Direct Containment Heating (DCH) issue resolution for Korean Standard Nuclear Power Plants (KSNPs), a containment load/strength assessment with two different approaches, the probabilistic and the deterministic, was performed with all plant-specific and phenomena-specific data. In case of the probabilistic approach, the framework developed to support the Zion DCH study, Two-Cell Equilibrium (TCE) coupled with Latin Hypercubic Sampling (LHS), provided a very efficient tool to resolve DCH issue. In case of the deterministic approach, the evaluation methodology using the sophisticated mechanistic computer code, CONTAIN 2.0 was developed, based on findings from DCH-related experiments or analyses. For three bounding scenarios designated as Scenarios V, Va, and VI, the calculation results of TCE/LHS and CONTAIN 2.0 with the conservatism or typical estimation for uncertain parameters, showed that the containment failure resulted from DCH loads was not likely to occur. To verify that these two approaches might be conservative , the containment loads resulting from typical high-pressure accident scenarios (SBO and SBLOCA) for KSNPs were also predicted. The CONTAIN 2.0 calculations with boundary and initial conditions from the MAAP4 predictions, including the sensitivity calculations for DCH phenomenological parameters, have confirmed that the predicted containment pressure and temperature were much below those from these two approaches, and, therefore, DCH issue for KSNPS might be not a problem.

• The Plant Pathology Journal
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• v.19 no.3
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• pp.159-161
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• 2003

The coat protein (CP) gene of Apple mosaic virus (ApMV), a member of the genus Ilarvirus, was selected for the design of virus-specific primers for amplification and molecular detection of the virus in cultivated apple. A combined assay of reverse transcription and polymerase chain reaction (RT-PCR) was performed with a single pair of ApMV-specific primers and crude nucleic acid extracts from virus-infected apple for rapid detection of the virus. The PCR product was verified by restriction mapping analysis and by sequence determination. The lowest concentration of template viral RNA required for detection was 100 fg. This indicates that the RT-PCR for detection of the virus is a 10$^3$times more sensitive, reproducible and time-saving method than the enzyme-linked immunosorbent assay. The specificity of the primers was verified using other unrelated viral RNAs. No PCR product was observed when Cucumber mosaic virus (Cucumovirus) or a crude extract of healthy apple was used as a template in RT-PCR with the same primers. The PCR product (669 bp) of the CP gene of the virus was cloned into the plasmid vector and result-ant recombinant (pAPCP1) was selected for molecule of apple transformation to breed virus-resistant transgenic apple plants as the next step. This method can be useful for early stage screening of in vitro plantlet and genetic resources of resistant cultivar of apple plants.

• Journal of Plant Biotechnology
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• v.39 no.4
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• pp.242-252
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• 2012

Seed storage oils are essential resources for not only human and animal diets but also industrial applications. The primary goal of this study was to increase seed oil content through comparative analysis of two seed-specific promoters, AtFAE1 from Arabidopsis Fatty Acid Elongase 1 gene and BnNapin from Brassica napus seed storage protein gene. AtWRI1 and AtDGAT1 genes encoding an AP2-type transcription factor and a Diacylglycerol Acyltransferase 1 enzyme, respectively, were expressed under the control of AtFAE1 and BnNapin promoters in Arabidopsis. The total seed oil content in all transgenic plants was increased by 8-11% compared with wild-type seeds. The increased level of oil content in AtWRI1 and AtDGAT1 transgenic lines under the control of both promoters was similar, although the activity of the BnNapin promoter is much stronger than that of AtFAE1 promoter in the mature stage of developing seeds where storage oil biosynthesis occurs at a maximum rate. This result demonstrates that the AtFAE1 promoter as well as the BnNapin promoter can be used to increase the seed oil content in transgenic plants.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.6
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• pp.513-518
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• 2006

This study was conducted to investigate the relations between brown planthopper (BPH, Nilapavata lugens) resistance and specific organic acids (oxalic acid, silicic acid, and trans-aconitic acid) known as BPH sucking inhibitors on different rice varieties and/or lines. There were no specific relations between BPH resistance and the contents of oxalic and silicic acids in the rice plant tissues. However, the stronger the BPH resistance was occurred, the higher the content of trans-aconitic acid was contained in the rice plants. The relations between the injury rate of rice plant by BPH and the content of trans-aconitic acid in the rice plants were negatively correlated, which were -0.84 and -0.82 at 30 and 60 days after seeding, respectively. Therefore, the content of trans-aconitic acid in rice plant tissues might be utilized as an index for improving BPH resistance of rice varieties.

• Journal of Korean Society of Water and Wastewater
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• v.14 no.4
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• pp.311-317
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• 2000

The operation of flocculation process and the evaluation thereof have been mainly based on G, t and $G{\times}t$ values which are available from design guidelines and texts. However, their suggested ranges are too wide to find the optimum condition specific to a particular water treatment plant and none of the existing method can be used to evaluate and suggest the optimum operational condition. Recently, a commercially available particle counter is found to be useful in determining the flocculation process based on the particle dynamics. The optimum condition is defined as one that best suits the purpose of flocculation; the number of small particles should decrease, while that of large particles should increase. The experiments were performed at two conventional water treatment plants in Korea, one with horizontal mechanical flocculators, and another with vertical type mechanical flocculators. In this paper, experiences to evaluate the flocculation process and to suggest the optimum operation condition will be presented. Although particle counting method is found to be beneficial compared to any other existing methods, the optimum condition is very much site-specific and should be evaluated at each water treatment plant for different conditions.

• The Korean Journal of Ecology
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• v.21 no.1
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• pp.47-63
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• 1998

In order to compare species-specific calcium metabolism, we collected 127 species belonging to 40 different families grown on various habitats including saline, limestone, wetland during the 1996 vegetation period, and analyzed their inorganic ion contents. Plants investigated were divided into 5 groups according to their physiological properties: 1) Chenopodiaceae, Aizoaceae, Caryophyllaceae, Portulacaceae and Phytolaccaceae of Centrospermales and Polygonaceae (Polygonales had a little water-soluble $Ca^{2+}$ but contained high contents of insoluble $Ca^{2+}$ particularly as Ca-oxalate (Chenopodiaceae type), 2) Some plant species such as Rosaceae produced oxalate in amounts insufficient to precipitate all incoming $Ca^{2+}$ and thus contained a surplus of dissolved $Ca^{2+}$ (Rosaceae type), 3) The contents of water-soluble $Ca^{2+}$ in plant species of Crassulaceae. Plantaginaceae, Asclepiadaceae, and Zygophyllaceae were equal to or greater than those of K ($K/Ca{\leq}1$; Crassulaceae type), and 4) K/Ca ratios of Compositae were significantly fluctuated depending on species and soil $Ca^{2+}$ level of their habitats (Compositae type). 5) Certain monocots (Gramineae, Cyperaceae, Juncaceae), in contrast to the dicotyledonous plant families mentioned above, showed a very distinct type of calcium metabolism, that is, the K/Ca ratios of 8~10 were maintained indifferently in the species and their habitat types (Graminae type). These results plants within the same taxon have similar physiological aspects as weel as morphological attributes. To understand calcium metabolism of certain plant species, therefore, it is desirable to approach on the basis of physiological concept (calciotroph or calciophobe) rather than the ecological one (calcicole or calcifuge).

• Korean Journal of Plant Resources
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• v.27 no.3
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• pp.236-241
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• 2014

A sex-linked random amplified polymorphic DNA (RAPD) marker was identified from Asparagus officinalis L. and was converted into a sequence-characterized amplified regions (SCAR) marker for the large-scale screening of male and female plants. A total of 100 arbitrary decamer oligonucleotide primers were used for the RAPD analysis. Among them, the primer UBC347 amplified one female-specific 400 base pair DNA. Subsequently, the amplified RAPD fragment was cloned and sequenced. The fragment was abundant in AT and shared sequence homology with retrotransposon elements. On the basis of the sequence obtained, a pair of SCAR primer was designed. The amplification product, named F400, was the same size as the respective RAPD fragment from which it was derived. The F400 SCAR marker resulted to be female-specific in the three asparagus varieties tested in this study. This SCAR marker can be used for an early and rapid identification of female and male plants during breeding programs of asparagus.

• Korean Journal of Plant Resources
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• v.20 no.2
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• pp.133-144
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• 2007

The vascular plants at the Wolmyung Park was listed 479 taxa: 105 families, 317 genera, 417 species, 1 subspecies, 55 varieties and 6 forms. 479 taxa listed consists of 291 taxa of edible plants (60.8%), 335 taxa of medicinal plants (69.9%), 234 taxa of ornamental plants (48.9%) and 243 taxa of the others (50.7%). Based on the list of the rare plants by the Forest Research Institute, 4 taxa were recorded in the investigated areas; Aristolochia contorta (Preservation priority order, No. 151), Magnolia kobus (No. 187), Prunus yedoensis (No. 110), Berchemia racemesa (No. 67) and based on the list of Korean endemic plants, 9 taxa were recorded; Cephalotaxus koreana, Carex okamotoi, Populus tomentiglandulosa, Prunus yedoensis, Forsythia koreana, Asperula lasiantha, Weigela subsessilis, Adenophora triphylla var. hirsuta, Aster koraiensis. Specific plant species by floral region were total 31 taxa; Prunus yedoensis, Berchemia racemosa in class V, Magnolia kobus, Wistaria floribunda in class IV, 4 taxa (Spiraea salicifolia, Acer palmatum, Asperula lasiantha, etc.) in class III, Caryopteris incana in class II, 22 taxa (Clematis patens, Orixa japonica, Euscaphis japonica, Grewia biloba var. parviflora, etc.) in class I. The naturalized plants in this site were 14 families, 35 genera, 44 species, 2 varieties, 46 taxa and naturalization rate was 9.6% of all 479 taxa vascular plants.

• Korean Journal of Plant Resources
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• v.19 no.4
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• pp.447-458
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• 2006

The resource plants at the Manduksan and Mireukbong was listed 550 taxa: 107 families, 339 genera, 481 species, 1 subspecies, 65 varieties and 3 forms. Among 550 taxa listed was confirmed 323 taxa of edible plants (58.7%), 384 taxa of medicinal plants (69.8%), 267 taxa of ornamental plants (48.5%) and 268 taxa of the others (48.7%). Based on the list of the rare plants by the Forest Research Institute, 4 taxa were recorded in the studied areas; Lilium distichum (Preservation priority order: No. 159), Tricyrtis dilatata (No. 97), Aristolochia contorta (No. 151), Prunus yedoensis (No. 110) and based on the list of Korean endemic plants, 11 taxa were recorded; Cephalotaxus koreana, Carex okamotoi, Lilium amabile, Populus tomentiglandulosa, Salix purpurea var. japonica, Pseudostellaria multiflora, Prunus yedoensis, Forsythia koreana, Paulownia coreana, Weigela subsessilis, Aster koraiensis. Specific plant species by floral region were total 30 taxa; Prunus yedoensis in class V, Wistaria floribunda in class IV, 3 taxa (Spiraea salicifolia, Acer palmatum, Asperula lasiantha) in class III, 3 taxa (Potentilla dickinsii, Viola tokubuchiana var. takedana, Caryopteris incana) in class II, 22 taxa (Pinus koraiensis, Hosta capitata, Chloranthus japonicus, Salix glandulosa, Juglans mandshurica, etc.) in class I. This site needs urgent countermeasures, because there have increased many man-made damages like planting exotic plants, picking wild plants and soil compaction induced by human trampling.