• Korean Journal Plant Pathology
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• v.13 no.2
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• pp.90-94
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• 1997

Interaction of races of rice blast fungus and cultivars has been evaluated. Dongjinbyeo was infected by four KJ races and two KI races, while other varieties were susceptible to four to six KJ or KI races. Among the single spores reisolated from the leaf blast lesion of Dongjinbyeo after mixed inoculation of 10 races, 63% was race KJ-301 which produced a small number and small size lesions, while 30% was race KI-313 which produced a large number of lesions. However, 93% of single spores reisolated from Palgongbyeo was a highly virulent race KJ-105. On the other hand, all the races were equally reisolated from the susceptible cultivar Jinmibyeo. Frequency of races isolated from the naturally infected leaf blast lesions in the field was similar to that of reisolated races from the cultivars inoculated with 10 mixed races in the greenhouse. However, 30% of single spores isolated from the naturally infected Dongjinbyeo was race KI-329 ut ace KI-313 was not detected. Genetic relationship of the isolates collected from leaf and neck blast fungus of Jinmibyeo and Nakdongbyeo showed specific bands on RFLP-P64, However, their genetic similarity was 80%.

• Korean Journal Plant Pathology
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• v.1 no.3
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• pp.178-183
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• 1985

The present researches were carried out to investigate the peroxidase activity in association with the reactions of the 4 cultivars of rice plant, Nagdong, Jinheung, Nongbaek and Taebaek to Pyricularia oryzae race KJ-I0l and KJ-301. Although the peroxidase activity was increased during the growth of the rice seedlings, the significant difference in the activity was not found among 4 cultivars. After inoculation of the fungus, the peroxidase activity was enhanced in diseased leaves, being considerably higher in the compatible than in the incompatible cultivars. The isozyme bands of peroxidases observed in mycelium of rice blast fungus were not found in the diseased leaves on the gel electrophoresis. The peroxidase activity was not affected by the increased application of nitrogenous fertilizer.

• KSBB Journal
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• v.21 no.4
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• pp.267-272
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• 2006

Five strains producing ethanol were isolated from soil near traditional alcohol production factory in Gwangju, Korea. One of the isolated strains maintained relatively stable ethanol production in shaking culture. The isolated strain KJ was proved to be Saccharomyces italicus, based on several biochemical and morphological tests containing assimilation of carbon compounds. In investment of the most suitable carbon for ethanol production, ethanol concentration of 5.46 g/L and yield of 0.53 g-ethanol/g-glucose were obtained in condition of glucose 10 g/L in YM medium. Experimental optimal conditions for ethanol fermentation by S. italicus KJ were as follows; temperature $30^{\circ}C$, initial pH 5.0, initial concentration 10% of glucose, anaerobic condition in the liquid cultivation. When enzymatically saccharified food wastes(SFW) were used as the production medium, ethanol production yield was 0.57 g-ethanol/g-reducing sugar. Therefore, SFW will contribute to lower the production cost of ethanol for industrial application.

• Journal of Microbiology and Biotechnology
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• v.23 no.3
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• pp.397-404
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• 2013

Paenibacillus xylanilyticus KJ-03 was isolated from soil samples obtained from a field with Amorphophallus konjac plants. A gene encoding xylanase was isolated from KJ-03 and cloned using a fosmid library. The xynA gene encodes xylanase; it consists of 1,035 bp and encodes 345 amino acids. The amino acid sequence deduced from the P. xylanilyticus KJ-03 xylanase showed 81% and 69% identities with those deduced from the P. polymyxa E681 and Paenibacillus sp. HPL-001 xylanases, respectively. The xynA gene comprises a single domain, consisting of a catalytic domain of the glycosyl hydrolase (GH) 10 family. The xynA gene was expressed in Escherichia coli BL21 (trxB), and the recombinant xylanase was purified by Niaffinity chromatography. The purified xylanase showed optimum activity with birchwood xylan as a substrate at $40^{\circ}C$ and pH 7.4. Treatment with $Mg^{2+}$ and $Li^+$ showed a slight decrease in XynA activity; however, treatment with 5 mM $Cu^{2+}$ completely inhibited its activity. The results of the thin layer chromatography analysis indicated that the major hydrolysis product was xylobiose and small amounts of xylose and xylotriose. XynA showed increased activity with oat spelt xylan and birchwood xylan, but showed only slight activity with locust bean gum.

• Journal of the Korean earth science society
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• v.45 no.1
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• pp.37-47
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• 2024

In the summer of 2018, the Korea-Japan (KJ) region experienced an extremely severe and prolonged heatwave. This study examines the GloSea6 model's prediction performance for the 2018 KJ heatwave event and investigates how its prediction skill is related to large-scale circulation patterns identified by the k-means clustering method. Cluster 1 pattern is characterized by a KJ high-pressure anomaly, Cluster 2 pattern is distinguished by an Eastern European high-pressure anomaly, and Cluster 3 pattern is associated with a Pacific-Japan pattern-like anomaly. By analyzing the spatial correlation coefficients between these three identified circulation patterns and GloSea6 predictions, we assessed the contribution of each circulation pattern to the heatwave lifecycle. Our results show that the Eastern European high-pressure pattern, in particular, plays a significant role in predicting the evolution of the development and peak phases of the 2018 KJ heatwave approximately two weeks in advance. Furthermore, this study suggests that an accurate representation of large-scale atmospheric circulations in upstream regions is a key factor in seasonal forecast models for improving the predictability of extreme weather events, such as the 2018 KJ heatwave.

• Journal of Life Science
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• v.8 no.3
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• pp.326-332
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• 1998

Cyclodextrin glucanotransferase from B. stearothermophilus KJ16 that can produce both cyclodextrin glucanotransferase and cyclodextrinase was purified by ammonium sulfate precipitation, DEAE-cellulose chromatography, Sephadex G-100 chromatography, and FPLC. The molecular weight of the purifice enzyme was about 65,000 dalton by SDS-PAGE. The optimal pH and temperature were 6.0 and $60^{\circ}C$, respectively. The enzyme was stable at $50^{\circ}C$ for 1 hr and in the pH range of 5.5 and 8.5. Mercaptoethanol and dithiothreitol inhibited the enzyme activity strongly. The enzyme produced 60% cyclodextrin(CD) from 5% soluble starch with the $^{\alpha}$, $^{\beta}$, $^{\gamma}$-CD ratio of 42:46:12. Amylopectin was the most suitable substrate with 67% conversion to CD.

• Journal of Photoscience
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• v.6 no.1
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• pp.1-3
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• 1999

Solar ultraviolet-A (UV-A) irradiances indicent on a horizontal surface at Taegu of Korea during 1995-1998 were calculated with 5 min averages of measurements taken every 30 seconds by a broadband UV- A sensor. The maximum and minimum of monthly averages of daily UV-A dose were 499.37 KJ m-2 day-1 inJuly and 171.09 KJ m--2 day-1 in December for 4 years of the observation period. The maxima of daily UV-A dose and instandaneous UV-A were observed as 846.46KJ m-2 day-1 June 7, 1998 and 37.22 W m-2 at 12 : 15, July 16, 1998, respectively. Increasing trends in annual maxima of daily UV-A dose and instantaneous UV-A were averaged to 6.4% and 6.7% , respectively, per year during 1995-1998 at Taegu, Korea.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.37 no.11
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• pp.762-771
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• 1988

This paper presents the experimental study to confirm the basic properties extract the operating problems of SMES. A new fast control system including u-computer and 12pulse power converter are designed and fabricated. The experiment of 25KJ SMES discharge and charge is carried out by I-C (Inductor-Converter) unit using a new proposed control system. The proposed control algorithm is proved by the simulations and control properties tests. It is also confirmed experimetally that SMES connected I-C unit controlled by this control scheme has an effects on compansating freguency fluctuation by independent active power control.

• Korean journal of applied entomology
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• v.23 no.3 s.60
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• pp.190-192
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• 1984

The 98 and 116 isolates of Pyricularia oryzae collected from Gyeong-nam Province in 1982 and 1983 were differentiated by using Korean differential rice cultivars. Twelve races from98 isolates and 11 races from 116 isolates of P. oryzae were classified indicating that KJ races group was $87\%$ and KI group was $13\%$ in total. The races KJ301 and KJ 401 were ca. $50\%$ in frequency among races identified.

• Microbiology and Biotechnology Letters
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• v.28 no.4
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• pp.219-222
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• 2000

To produce and utilize microbial cyclomaltodextrinase being industrially useful, we isolated an alkalophilic Bacillus strain from soil which was capable of degrading cyclodextrins. The newly isolated strain was aerobic, gram-positive, spore-forming, motile, rod shape(0.2~0.4$\times$1.4~4.4 $\mu\textrm{m}$), and 35.8 mol% of DNA base composition. Based on its morphological, phisiological, and biochemical properties, it was identified as alkalophilic Bacillus sp. KJ-133 and cultivated well in the ranges of $30~40^{\circ}C$ and pH 8.0~9.0 . The cyclomaltodextrinase of the strain showed maximal production after 48h of cultivation at $37^{\circ}C$, and the activity was inhibited by Ag2+, Hg2+, Cu2+, and p-chloromercuribenzoate.