• KOREAN JOURNAL OF CROP SCIENCE
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• v.20
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• pp.27-62
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• 1975

These studies were aimed at clarifying whether or not selecting agronomic characteristics of hybrid-rice populations under greenhouse conditions was useful. The selection of two quantitative characteristics, culm length and heading date, and two qualitative characteristics, shattering and awnedness, was very effective, but the flag leaf length and the exsertion of panicle was not consistent, varying from one cross to another.

• Korean Journal of Environment and Ecology
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• v.30 no.4
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• pp.724-729
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• 2016

Environmental factors that affect the singing of cicadas have not been studied extensively, especially those affecting the cicadas' singing during the nighttime. Therefore, the objective of this study is to identify the effects of tropical night and light pollution on the cicadas' singing in a downtown area. The study sites were an apartment complex in Seocho-gu, Seoul, and the Chiaksan National Park in Wonju-si. The study subjects were Hyalessa fuscata and Cryptotympana atrata, which are the dominant species in Korea during summer. Cicada songs were recorded 24 hours a day, every day. The recording period was between July and August, lasting 25 days at the Seoul site and 14 days at the Chiaksan National Park. Temperature, precipitation, humidity, and amount of sunshine were selected as the environmental factors that potentially affect the cicadas' singing. Statistical analyses included correlations of meteorological factors with the cicadas' singing per hour, per 24 hours, and at nighttime (21:00~04:00). The results showed that: 1) H. fuscata began singing during the dawn hours, and the singing increased in intensity early in the morning. C. atrata's singing reached its peak in the morning and afternoon, ceased during sunset hours, thereby exhibiting a difference in the singing pattern of the two species. 2) The frequency of singing by H. fuscata decreased when C. atrata began to sing intensively in numbers, thereby exhibiting interspecific influence. 3) The results of the correlation analysis between meteorological factors and the singing of H. fuscata and C. atrata showed that both species tended to sing more when the temperature was higher and sang less on rainy days. 4) When limited to nighttime only, C. atrata showed a tendency of singing when the nighttime temperature was high ($24-30^{\circ}C$, average $27^{\circ}C$), whereas H. fuscata did not show a correlation with meteorological factors. However, since H. fuscata sang during the night in areas with artificial lighting, it was concluded that its singing was due to light pollution.

• Journal of the Korean Society for Marine Environment & Energy
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• v.16 no.1
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• pp.25-35
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• 2013

Dominance and survival strategy of toxic dinoflagellate Alexandrium tamarense and A. catenella under the dissolved inorganic nitrogen (DIN) limited conditions were examined in the laboratory and field observations. In Masan Bay, DIN was limiting factor for growth of phytoplankton during spring to early summer when Alexandrium spp. have been observed. They have a disadvantageous position compared with diatoms because Ks of nitrate calculated from growth kinetics experiment of A. tamarense and A. catenella was higher than diatoms. However, A. tamarense and A. catenella were able to grow using dissolved organic nitrogen (DON) compounds such as urea and amino acids as well as DIN. Therefore, DON utilization of A. tamarense, A. catenella might contribute to not only their population growth but also dominance and interspecific competition in the DIN-limited conditions in Masan Bay.

• The Korean Journal of Pesticide Science
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• v.8 no.1
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• pp.30-37
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• 2004

This study estimated the correlation between surface area/weight ratios and pesticide residues in two varieties of tomato, mini tomato and tomato. The ratios of surface area/weight of mini tomato and tomato were $2.15cm^2g^{-1}$ and $1.00cm^2g^{-1}$ respectively. Pesticide residues were measured with four kinds of pesticide, chlorothalonil WP, chlorothalonil SC, oxadixyl WP, thiophanate-methyl WP. Ie residue amount of mini tomato was $1.4\sim2.4$ times higher than those in tomato regardless of the application date and frequency. The ratios of surface area/weight on tomato varieties played a key role for determining pesticide residue.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.3
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• pp.270-274
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• 1997

This experiment was conducted to evaluate the combining ability of japonica rices for improving the salinity tolerance at seedling stage. Nine varieties used in partial diallel analysis included three varieties of each tolerant, moderately tolerant and susceptible one. Twelve-day-old seedlings were grown in saline solution, initially at an EC of 6 dS /m for four days, followed by an EC of 12 dS /m for 20 days. The agronomic characters at seedling stage such as plant height, dry shoot weight and dry root weight were measured to analyze for combining ability of the parents. General combining ability(GCA) and specific combining ability(SCA) effects were highly significant for all tested parameters. However, mean squares for GCA were about five times larger than that for SCA suggesting the preponderance of additive gene action. Among tolerant varieties, Gaori and Namyang 7 were good combiner for improving the salinity tolerance at seedling stage in GCA as well as SCA.

• The Korean Journal of Zoology
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• v.31 no.1
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• pp.29-34
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• 1988

In order to investigate the role of nuclei and cytoplasm in early embryogenesis, interspecific nuclear transplantation was carried out Nuclei of one species of amphibian was transplanted into enucleated egg of another species. In interspecific hybrids between Rana species, development was arrested before or right after the dorsal lip formation. In intergenetic hybrids between Rana, Xenopus and axolod, developmental arrest took place at late blastula stage. Comparing the developmental capacity of each nudeocytoplasmic hybrid, the more distantly related the species, the earlier does development arrest. The general rule is that nuclear transfers between any amphibian species will form a regulary cleaved late blastula. Two plausible factors relate to limitation of tite developmental capacity of nudeocytaplasmic hybrids. One is an irreversible change in grafted nuclei and another is tunctional incompatibility between the recipient cytoplasm and transplanted nucleus. The later is postulated a more possible cause of the arrestrnent.

• Journal of Digital Convergence
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• v.12 no.3
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• pp.345-352
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• 2014

This study proposes a more comprehensive approach for FLD by analyzing the relationship of colorectal polyps, which are precursors of colorectal cancer. In Chi-Square tests of FLD and colorectal polyps, the prevalence of colorectal polyps was significantly high in cases of FLD. The polyps and correlation of each factor showed a positive relationship with all factors, and the correlation coefficient with FLD was highest (r = 0.39, p <.001). In multiple regression analysis, FLD(OR 3.80 95% CI 1.93.-7.50), FBS (OR 2.51; 95% CI 1.12-5.62), and older age (OR 2.12; 95% CI 1.27-3.54) were independent risk factors for colorectal polyps. FLD was associated with the prevalence of colorectal polyps. These results show a meaningful influenceof FLD by ultrasonography in the occurrence of colorectal polyps, and that positive consideration of colonoscopy is needed for diagnosed FLD.

• Proceedings of the Ginseng society Conference
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• 1988.08a
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• pp.133-138
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• 1988

The traditional concept of ginseng quality was investigated in relation to historical experiences. traditional quality measure and mordern analytical method. The traditional concept appears to be based on the original Korean thought of oneness in life and universe. The outside appearance such as shape and size in traditional quality measure includes the inside quality. Since certain shape and size define specific tissues. cells and biologically active substances in cells the traditional measure will he a map for analytical method to find active principles. Traditional method suggests that the balance among biologically active compounds seems to he more important than the large amount of one active compound and that the mode of active compounds in ginseng for the homeostasis of human body is the multicompound to multitarget system. Traditional method strongly suggests the importance of nitrogen compounds. especially soluble protein and heat stable protein for the balance of active principles since nitrogen compounds are more abundant in the central part (xylem-pith) that grows faster than the outer part (cortex-epidermis). The balance of physiologically active principles appeares to be meaningful in relation to the difference in traditional use of Panax species.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.3
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• pp.254-260
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• 1982

Ten soybean varieties were cultivated to know the varietal differences of lodging patterns of soybean plants under three different plant populations in two growing seasons in 1981. Lodging plant percentage was increased in higher plant populations and lodging responses to plant populations were different between soybean varieties. Lodging plant percentage was also increased by the growth of soybean plant and the patterns of lodging development along with the growth stages could be classified into four types by the varieties used, relatively lwoer iodging plant percentage from early to later growth stage but high in late and relatively high in middle stage but low in later stage. Williams, indeterminate type, and Kang-lim, determinate type, showed resistance to lodging under six different cultural practices, but Jang-yeop-kong, Dan-yeop-kong and Hwang-keum-kong showed resistance to lodging under specific cultural conditions among ten varieties used. Most of the plants lodged showed main stem bending in parts above first stem node in higher plant population and lodging resistant varieties showed lower frequency of stem bending lodging compared with those of lodging susceptible varieties.

• Korean Journal of Soil Science and Fertilizer
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• v.10 no.2
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• pp.85-92
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• 1977

The six soybean cultivars (Lee, Hill, Harosoy, Clark-63 Chippewa and R56-49) different in phosphorus sensitivity were cultured with $NH_4-N$, $NO_3-N$ or urea-N under water culture condition. Free sugars and organic chrematogram. Three peaks (unknown x, y and sucrose) were appeared as considerable main peaks. The X compound appeared as trace in the nitrate fed plant while unexpectedly high in ammonium or urea fed plant. The Y compound tend to decrase in urea fed plant. Sucrose was trace in ammonium fed plant but it was greater in urea onethan in nitrate one. The X was assumed a four carbon sugar acid derived from erythrose or a ring compound derived from purine or pyrimidine. While Y was assumed a hexose derived from glycolysis path. Since Y/x ratio is a good index of phosphorus sensitivity (inve rserelation) these compounds appears keycompounds to elucidate phosphorus sensitivity and ammonium toxicity.