• KOREAN JOURNAL OF CROP SCIENCE
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• v.21 no.1
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• pp.35-42
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• 1976

In Korea, two types of rice varieties are being cultivated widely, Japonica and Japonica-Indica cross. Generally speaking, the latter shows weak cold tolerance than the former and so brought about many problems in cultural practices. This study was conducted to investigate the effect . of various temperature conditions on rice seedlings growth, especially the contents of chlorophyll and the percentage of nitrogen. And the result obtained indicated the varieties of Japonica-Indica intend to weak cold tolerance than Japonica varieties.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.2
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• pp.137-143
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• 1987

To find out the optimum storage temperature and duration, changes in the content of sugars and soluble solids and flavor rate of two sweet corn hybrids (Great Bell and Golden Cross Bantam) and a super sweet corn (Crisp Super Sweet 720) were observed after storing at -20, 0, 5, 10, 15, 20, and 25$^{\circ}C$ for 1,3,5, and 7 days. At the temperatures below 10$^{\circ}C$, contents of soluble solids and total sugars and flavor rate were not changed significantly, but at the temperatures higher than 15$^{\circ}C$ they decreased as storage temperatures increased and duration extended. Storage duration conserving flavor seems to be 7 days at temperatures below 10$^{\circ}C$, 3 days at 15$^{\circ}C$, and 1-2 days at 25$^{\circ}C$. When corn was frozen, flavor rate was a little low compared with corn stored at 0$^{\circ}C$ although sugar content was higher. Both soluble solids and total sugar contents were positively correlated with flavor rate of cooked corn.

• Journal of fish pathology
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• v.22 no.2
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• pp.97-105
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• 2009

Scuticociliates Miamiensis avidus (syn. Philasterides dicentrarchi) causes high mortality and bad growth in olive flounder Paralichthys olivaceus. Temperature is an important factor not only for growth of pathogens but also for host immune system in poikilothermal animal. In this study, temperature affecting ciliate growth and pathogenicity against olive flounder were examined. Doubling time for the ciliate growth was 61.82 hours at $5{^{\circ}C}$, 26.32 hours at $10{^{\circ}C}$, 21.14 hours at $15{^{\circ}C}$, 16.86 hours $20{^{\circ}C}$ and 16.21 hours at $25{^{\circ}C}$. Maximum ciliate numbers were similar at $10-20{^{\circ}C}$ at the range of $1.54-1.75{\times}10^{5}$/ ml. Duplicated intraperitoneal injections were conducted with the ciliates by the concentrations of $1{\times}10^{2}$, $1{\times}10^{6}$, $1{\times}10^{4}$and $1{\times}10^{5}$/ fish (average 8.34 cm, 4.33 g) then kept at $10{^{\circ}C}$, $15{^{\circ}C}$ and $20{^{\circ}C}$. Cumulative mortality was low at $10{^{\circ}C}$ and the mortality was increasing at higher water temperatures. In addition, cumulative mortality was higher at higher dose of infections. In conclusion, Scuticocilite M. avidus grew well at higher temperature (at $5{^{\circ}C}$, $10{^{\circ}C}$, $15{^{\circ}C}$ and $25{^{\circ}C}$) in vitro, and olive flounder mortality due to M. avidus was highly water temperature and dose dependent. The results of this study suggest that water temperature control may one of the essential factor to reduce mortality due to M. avidus infection.

• Korean journal of applied entomology
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• v.37 no.2
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• pp.159-162
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• 1998

Effect of temperature on oviposition and developmental period of Oulema oryzae K. on riceplant were investigated. With the given set of temperatures of 15, 20, 23, 25, and 28"C, developmentalperiod from egg to adult emergence was shorten as temperature increased. Average number of eggs perfemale 0. oryzae increased as temperature increased from 15$^{\circ}$C to 23"C, then decreased at 25$^{\circ}$C and 28"C. Based on this result, developmental threshold temperatures for egg was estimated to be 6.4"C. Totaleffective temperatures above the thresolds required for hatching were estimated to be 75.8 degree-daysfor egg. It seemed that the optimum temperature for oviposition of Oulema oryzae on rice plant was 23"C.a oryzae on rice plant was 23"C.quot;C.

• Korean Journal of Materials Research
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• v.15 no.2
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• pp.85-88
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• 2005

[ $W-15wt.\%$ ] Cu nanocomposite powders are fabricated by ball-milling and subsequent hydrogen-reduction. The compacted parts of $W-15wt.\%Cu$ nanocomposite powders were sintered at $1200^{\circ}C$ for 1 h with various heating rates of 5 and $20^{\circ}C/min$. The homogeneity of the sintered microstructures was evaluated through homogeneity index by the standard deviation of Victor's hardness test. The W-W contiguities were calculated by using Voronoi diagrams. The sintered microstructure with the heating rate of $20^{\circ}C/min$ was more homogeneous and had lower W-W contiguity than that of $5^{\circ}C/min$. The microstructural homogeneity was directly related to the W-W contiguity. Thermal conductivity of the sintered parts with the heating rate of $20^{\circ}C/min$ was higher than that with heating rate of $5^{\circ}C/min$. This phenomenon indicates that the thermal conductivity is affected by the W-W contiguity resulting from the homogeneity of the sintered microstructure.

• Journal of Bio-Environment Control
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• v.9 no.4
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• pp.207-211
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• 2000

This study was conducted to investigate the effect of soil zone temperature on the growth responses of two grapevine varieties. Campbell Early was cultivated under unprotected environment and Black Olympia was cultivated in the greenhouse. As responses, growth, photosynthetic rate and contents of mineral elements as affected by four different soil zone temperatures (10, 15, 20, and $25^{\circ}C$)were examined. Weights of leaves, stems and roots were higher at 20 and $25^{\circ}C$ than at 10 or 15$^{\circ}C$ root zone temperature in both varieties. Chlorophyll concentration and photosynthetic rate were the greatest at 2$0^{\circ}C$ root zone temperature. Contents of phosphate, potassium, and calcium increased with increasing root zone temperature.

• Korean Journal of Poultry Science
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• v.29 no.3
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• pp.157-170
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• 2002

This experiment was conducted to investigate the change of egg qualify by the height of thick albumen of egg, storage temperature and storage period. The albumen index and Haugh unit were measured and compared among five different storage periods(0, 2, 4, 6, and 10 days), four different storage temperatures($15^{\circ}C$ , $20^{\circ}C$ , $25^{\circ}C$ and $30^{\circ}C$ ), and five different Parts(0, 3, 6, 9, and 12 mm) aparted from egg yolk. The albumen index and Haugh unit were as follows: the albumen index of eggs was significantly(P<0.01) different by the storage temperature and by the measuring position of thick albumen of eggs. It means that the albumen index can be differed by the measuring position of thick albumen even if eggs have a same qualify. For measuring egg qualify in this country, it should be announced that which Parts in thick albumen of eggs are measured. The albumen index of fresh eggs was 0.16. However, the index when measured at 3 hour after oviposition was lower than 0.16. Therefore, it indicates that the criterion of 0.06 lower than 0.16 is required to set for considering practical point during the marketing periods of eggs. When the criterion of albumen index puts 0.06, it is as 100%. Therefore, eggs can be kept the same quality for 6, 4 and 2 days when eggs were stored at $15^{\circ}C$ , $20^{\circ}C$ and 25 ~$30^{\circ}C$ , respectively. When the criterion of Haugh unit score puts 79 as 100%, the eggs can be maintained the quality for 6, 4, and 2 days when eggs are stored at $15^{\circ}C$ , $20^{\circ}C$ and 25~$30^{\circ}C$ , respectively. When the criterion of Haugh unit 55 as 100%, the eggs can be maintained the same quality for 10, 8 and 2 days when eggs are stored at $15^{\circ}C$ , $20^{\circ}C$ and 25~$30^{\circ}C$ , respectively. From the experimental results, it can be considered that calculathing egg quality by the height of thick albumin of eggs which was measured at the attachment Parts of thick albumin layer and yolk of eggs was most reasonable and suitable when considering the marketing periods of eggs.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.4
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• pp.413-419
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• 1995

This study was conducted to find out the suitable NaCl concentration and temperature for investigating the varietal difference of salinity tolerance in Italian ryegrass. Seeds of 20 cultivars including 9 diploid and 11 tetraploid were exposed to eight levels of NaCl concentration ranging from 0 to 350mM under three temperature levels of 15, 20 and $25^{\circ}C$. The NaCl concentration(C50%) inhibited germination of 50% of the viable seeds for the cultivars at 15$^{\circ}C$ was 354mM, and those at 2$0^{\circ}C$ and $25^{\circ}C$ were 342mM and 325mM, respectively. There were significant correlations among C50% at three levels of temperature, and correlation coefficient for C50% between 2$0^{\circ}C$ and 15$^{\circ}C$ was higher than that between $25^{\circ}C$ and 15$^{\circ}C$ or 2$0^{\circ}C$. C50% was positively correlated only with germination speed at 10 days after sowing when the plants were exposed to 350mM NaCl at 2$0^{\circ}C$. For the germination speed at 10 days after sowing in 350mM NaCl at 2$0^{\circ}C$, the cultivars used could be classified into three groups. Wase Aoba, Bettina, E. K -11, Tetrone, Lira Sand, Tetra Florum and Billiken belonged to the tolerant group, and Tuchi Was, Wase Yutaka, Sakura Wase, Magnolia, Limella and Delita were as the semi-susceptible group, and Atalja, Barmultra, Ajax, Liberta, LM-16, Elving and Wilo were as the susceptible group.

• Microbiology and Biotechnology Letters
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• v.20 no.3
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• pp.257-262
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• 1992

Virginiae butanolide (VB) is an autoregulator which triggers virginiamycin production in Strefltomyces virginiae. VB-C binding protein activity was investigated under various additives. The VB-C binding protein was almost fully observed in sotubte fraction (>90%) and the binding activity was optimum at pH 7.0. The VB-C binding activity was increased about 15% in 0.5 M KCI, whereas decreased about 60% in 20 mM $Mo^{6+}$. Chelating reagents (ethylenediarnine tetraacetic acid, ethyleneglycol bis(2-aminoethylether) tetraacetic acid, 8-hydroxyquinoline) and SH protecting reagents (rnercaptoethanol, dithiothreitol, thioglycerol) inhibited the VB-C binding activity about 30~55% and 3~20%, respectively. Serine protease inhibitor (phenyl methane sulfonyl fluoride), nucleotides (guanosine 5'-monophosphate, adenosine 3',5'-cyclic monophosphate), and phosphatases (alkaline, acid phosphatase) increased the VB-C binding activity about 17%, 6~20%, and 4- 13%, respectively.

• Korean journal of applied entomology
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• v.45 no.3 s.144
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• pp.381-383
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• 2006

The hatching rate of the eggs of Nannophya pygmaea Rambur, an endangered dragonfly species in Korea, was experimented in different temperature conditions ($10,\;15,\;20,\;25,\;and\;30^{\circ}C$) in laboratory. N. pygmaea eggs were collected from female adults inhabited a small wetland in Mungyong-si, Kyeongsangbuk-do, Korea, in July 2006. The hatching rate was evaluated from the number of hatched nymphs for the period of 100 days. As a result, the hatching rates were 83, 89, and 76% at $20,\;25,\;and\;30^{\circ}C$, respectively; however, eggs were not hatched at $10^{\circ}C\;and\;15^{\circ}C$ during the experiment period. The derived thermal threshold for egg hatching was $14.3^{\circ}C$, which is relatively higher than the values of other temperate dragonflies.