• Vacuum Magazine
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• v.2 no.4
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• pp.39-46
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• 2015

After stepping into a new field of vacuum 30 years ago, our company has grown up steadily as a specialized vacuum industry, and now we can provide vacuum devices covering most of the pressure range. We are planning to put out high level dry pump like a multistage Roots pump on the market in the near future. Procedures of technology development for designing, fabricating, and testing the multistage Roots pump of 600 L/min class will be briefly reported. Core items of the technical development on the multistage Roots pump are as follows; elaborated profile design of 3-lobe rotors using an involute curve, optimization of rotor dimensions, especially for clearances and rotor width, considering the pumping speed, compression ratio and heat load, and establishment of a standardized test system. At present, the multistage Roots pump is about to come into commercialization.

• Mycobiology
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• v.42 no.4
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• pp.416-421
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• 2014

In this study, we examined arbuscular mycorrhizal fungal (AMF) community structure colonizing field-cultivated ginseng roots according of different ages, such as 1- to 5-year-old plant, collected from Geumsan-gun, Korea. A total of seven AMF species namely, Funnelliformis caledonium, F. moseae, Gigaspora margarita, Paraglomus laccatum, P. occultum, Rhizophagus irregularis, and Scutellospora heterogama were identified from the roots using cloning, PCR-restriction fragment length polymorphism and sequence analysis of the large subunit region in rDNA. AMF species diversity in the ginseng roots decreased with the increase in root age because of the decreased species evenness. In addition, the community structures of AMF in the roots became more uniform. These results suggest that the age of ginseng affects mycorrhizal colonization and its community structure.

• Journal of the Korean Society of Tobacco Science
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• v.25 no.1
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• pp.80-86
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• 2003

The contents of valepotriates, valerenic acid and their derivatives as mild sedative and antispamodic principles in two Korean valerian roots (Valeriana officinalis var. latifolia Miq. and V. fauriei var. dasycarpa Hara) were investigated and were compared with those in European valerian roots(Valeriana officinalis L.) by BPLC method. Among valepotriate compounds, valtrate was detected as a small amount in two Korean valerian roots, and iso-valtrate and dihydrovaltrate were detected as a trace amount. Among valerenic acid and their derivatives, valerenic acid were contained from 0.9∼3.46 mg/g base on dry weight. Over the vegetation periods investigated, the content of valepotriates remained more or less constant, hut the content of valerenic acid reached its maximum in 3-year old age. The compound isolated from Korean V. officinalis var. latifolia was elucidated as valerenic acid by spectroscopic data such as GC-MS, $^1$H-NMR and $^{13}$ C-NMR, and comparison of GC retention time with that of authentic compound.

• The Korean Journal of Ecology
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• v.7 no.2
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• pp.85-90
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• 1983

There was a decrease in nitrate reductase activity (NRA) measured in vivo in rice roots (Oryza sativa cv. Tongil) grown in anaerobic culture solution. But it was reversed by addition of malonate to the in vivo nitrate reduction assay medium. Malonate increased the in vivo NRA during 2-5 hours incubation and decreased it in longer incubation hours. In vivo NRA was stimulated by addition of NaHCO3 to the assay medium, but not by Na2CO3. The stimulation of NRA by NaHCO3 was not observed in shoot removed rice roots. It is suggested that CO2 from NaHCO3 is carboxylated by phosphoenol pyruvate carboxylase, results in increasing the malate contents in the roots, and stimulates the in vivo NRA. NADH needed in nitrate reduction is supported by malate oxidation. In rice roots, it seems probable that malate oxidation in the mitochondria is more important to nitrate reduction than malae oxidation in cytoplasm.

• The Plant Pathology Journal
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• v.18 no.4
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• pp.169-178
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• 2002

Orchids are evolutionally known to be the most advanced plants in the order Liliales, and comprise approximately 1,000 genera and 35,000 species world-wide. In Korea, more than 110 species of Orchidaceae have been reported to be cultivated or to be collected in the wild. Orchids aye mostly dependant on orchid mycorrhizae(OM) throughout or in part of their life cycle. The OM endomycorrhizae belonging to basidiomycetes or rarley ascomycetes are needed for orchid seed germination. Various fungi, including plant pathogenic, antagonistic and symbiotic fungi, were isolated from the roots of orchid native to Korea. The OM fungi collected from the roots of Cymbidium goeringii were three species of Rhizoctonia namely, R. repens (anamorph state of Tulsanella repens), R. endophytica (Ceratobasidium cornigerum), and an unidentified species (possibly an anamorph of T. calospora). These symbiotic fungi induced peloton in the cortical cells of orchid roots, and differed biologically and in 18s rDNA sequences from plant pathogenic Rhizoctonia species. Also, the mycorrhyzal fungi enhanced the orchid root absorption of nitrogen sources and minerals from the soil. The activity of mycorrhizal fungal hyphae in the roots caused prevention from pathogenic fungi. In nature, the peloton is observed in the cortical cells of Cymbidium goeriingii roots, indicating mycorrhizal colonization in the native orchid roots. On the other hand, pathogenic fungi such as Fusarium and/or Rhizoctonia species are mostly isolated from commercial orchid plants. These suggest that application of symbiotic mycorrhizal fungi should be needed for orchid cultivation in nurseries and at the time of transplanting.

• Food Science and Biotechnology
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• v.17 no.2
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• pp.430-433
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• 2008

A high performance liquid chromatography (HPLC) method has been successfully developed to identify and quantify major ginsenosides in Korean ginseng seeds and roots. Using gradient elution of acetonitrile and water without buffer, the 6 major ginsenosides ($Rb_1,\;Rb_2$, Rc, Rd, Re, and $Rg_1$) were identified. Compared with ginseng roots, the amount of ginsenoside Re and Rd in ginseng seeds were significantly higher than those in ginseng roots (p<0.05). In ginseng seeds, the content of protopanaxtriol (PPT) was higher than that of protopanaxdiol (PPD) and the ratio of PPT and PPD was approximately 2.2 : 1. However, the content of PPT was lower than that of PPD in ginseng roots. It should be mentioned that both content of PPT and PPD in ginseng seeds were much higher than those in ginseng roots.

• Applied Biological Chemistry
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• v.38 no.1
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• pp.72-77
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• 1995

The relationships between the soil chemical properties of ginseng fields and the contents of effective constituents in ginseng roots was investigated. The $NO_3-N$ contents in soils showed highly negative correlations with the contents of total sugar and reducing sugar in ginseng roots. The organic matter contents in soils showed positive correlations with the contents of sugar and ginoside in ginseng roots, while the contents of available phosphorus and exchangeable cations in soils showed highly negative correlations with the those in ginseng roots. For the Production of ginseng root of higher saponin contents, increase of the organic matter contents, and decrease of the contents of available phosphorus and exchangeable cations in soils were recommended.

• The Korean Journal of Mycology
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• v.20 no.2
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• pp.126-133
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• 1992

Using the soils containing several arbuscular mycorrhizae, the degrees of infection on the plant roots were measured with the different level of phosphate added on pot cultures. Infection on the plant roots was independent of the phosphate level for the roots of sorghum, but formation of arbuscular mycorrhizae in the roots was inversely related to the growth of soybean roots. It was concluded that infection of arbuscular mycorrhizae would be related to the phosphate level in the soils. Plants, themselves, were considered to control the infection of arbuscular mycorrhizae under the environments of soils, especially amount of phosphate.

• Journal of Plant Biology
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• v.33 no.2
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• pp.119-126
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• 1990

The content of canavanine was measured and analyzed in leaves, roots and xylem exudate of Canavalia lneata. In non-nodulated plants, the cotyledons were removed after a week of sowing and the plants were grown for 3 weeks. The quantity of canavanine measured by canavanine specific-PCAF colorimetric assay was 9-10 $\mu$mol/g fresh wt. in leaves, 5-6 $\mu$mol/g fresh wt. in roots, and 0.3-0.5 $\mu$mol/ml in xylem exudate. When free amino acids of leaves, roots, and xylem exudate were analysed by HPLC, the relative proportion of asparagine plus glycine was the highest and canavanine was high secondarily. And the relative proportion of canavanine among total free amino acids was 30-35% in leaves and roots, and 12-13% in xylem exudate. In non-nodulated plants grown for 8 weeks, the canavanine content of each part was similar to that of 3-week-old plants. By the formation of nodules, the canavanine content of leaves, roots, xylem exudate, and nodules decreased apparently. In xylem exduate, the nitrogenous compounds were also analyzed. The relative contents of NO3-, free amino acids, and ureides(allantoin and allantoic acid) were 60-80%, 20-30%, and 5%, respectively. From these results, it can be assumed that canavanine is synthesized in the root of plant and nodulation affects the canavanine content. It is obvious that canavanine is considered one of the reduced-N forms transported via xylem.

• Korean Journal of Human Ecology
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• v.23 no.4
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• pp.613-631
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• 2014

Personality education activities based on the roots of empathy program were designed and practiced in this study to investigate their effects on young children's empathic ability and emotional intelligence. The subjects of this research were 60 five years old of 2 classes in 'W' kindergarten in 'I' city, Jeonra Buk province. We randomly assigned 30 children of one class to the experimental group and 30 children of the other class to the controlled group. The personality education activities based on the roots of empathy program was by the researcher. The results of this study are summarized as follows. First, the personality education activities based on the roots of empathy program improved children's empathic ability. And that effects are shown in all sub-areas of empathic ability(sorrow/burden/joy/fear). Second, the personality education activities based on the roots of empathy program improved children's emotional intelligence. And that effects are shown in all sub-areas of emotional intelligence(recognition and expression of emotion/promotion of thinking by emotion/application of emotional knowledge/emotional reflective control).