• Development and Reproduction
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• v.10 no.1
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• pp.41-45
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• 2006

The spawning behavior of Liobagrus obesus was observed at Kumgang river, Yeongdong-gun, Chungcheongbuk-do from Apirl to July 2004. The fertilized eggs collected by dip net and skimming net were carried to the laboratory of Chonnam National University, and then egg, larvae and juvenils development were studied. Hatching of the embryo began about at 225 hrs 15 mins after morula stage in water temperature of $19.5{\sim}24.9^{\circ}C$(mean $22.8^{\circ}C$). The newly-hatched larvae were $7.30{\sim}7.90mm$(mean 7.66mm) in total length (TL), their mouth and anus were already opened with 14+28=42 myotomes. Sixteen days after hatching, the postlarvae were $13.00{\sim}14.05mm$(mean 13.48mm) TL, the yolk sac was completely absorbed. The juvenile stage was reached when all fin-rays were formed at 24 days after hatching, and $15.31{\sim}17.20mm$(mean 16.31mm) TL.

• KDI Journal of Economic Policy
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• v.13 no.4
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• pp.59-90
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• 1991

The purpose of this paper is to determine whether the rate schedule of the Korean income tax system embodies the theoretically desirable distribution of the tax burden by income classes. The paper follows the approach of Young (1990) who has estimated the utility function and calculated the magnitude of sacrifice, i.e., the tax burden. The main point of the study is to estimate the utility function. The estimation results may differ if different data sets are used. Therefore, this paper employs the effective as well as the nominal tax rate schedule. The findings derived in this paper are 1) that the effective rate schedule is more appropriate in estimating the utility function; 2) that the middle class has born the relatively heavier burden over time; 3) that the current income tax credit scheme curtails the tax burden on the middle class while intensifying the tax burden of the lower and upper income classes; 4) that reducing the amount of deduction moves the distribution of tax burdens by income classes closer to the theoretically desirable model; 5) that the rate schedule of the Korean income tax system, particularly in 1991, did not conform to the desired model as did the tax systems of developed countries such as the United States, Italy, Japan, and Germany.

• Parasites, Hosts and Diseases
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• v.26 no.4
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• pp.255-262
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• 1988

An epidemiological study on brugian filariasis was carried out in endemic areas including Cheju Island in Korea, with a brief review of literatures. The results showed that the incidence among residents has remarkably decreased in Cheju Island, which was the main endemic area. Reviewing available informations on the prevalence of filariasis reported in recent years and also judging from the present socio·economic conditions which enable people to practice personal protection against mosquitos, it can be said with confidence that alariasis has almost disappeared from Cheju Island and inland areas. The disease is considered to remain at a low level of endemicity in Hugsan Islands. Certainly mass diethylcarbamasine (DEC) treatment carried out in Cheju Island in the 1960s and 1970s and remarkable economic growth followed by improved living standard and altered life-style of inhabitants could all have combined effects on the disappearance of this mosquito-borne disease in this island. If the present trends go on, the possibility of resurgence of filariasis in Cheju Island is hardly postulated.

• Journal of the Korean Chemical Society
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• v.60 no.1
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• pp.16-20
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• 2016

The solvolysis rate constants of biphenyl-4-carbonyl chloride (C₆H₅C₆H₅COCl, 1) in 19 different solvents are well correlated with the extended Grunwald-Winstein equation, using the N_T solvent nucleophilicity scale, Y_Cl solvent ionizing scale, and I aromatic ring parameter with sensitivity values of 0.31±0.10, 0.46±0.05, and 0.96±0.20 for l, m, and h, respectively. These l, m, and h values can be considered to support a dissciative S_N2 reaction pathway. This interpretation is further supported by the activation parameters, i.e., relatively small positive ΔH^‡ (15.3~16.1 kcal/mol) values and large negative ΔS^‡ (−17.2~−20.0 cal/mol·K) values.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.5 no.2
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• pp.169-180
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• 2010

Objectives: This study was carried out to investigate the relationship of leg length analysis and X-ray finding according to positions and valuation bases on diagnosis of pelvic malpositions. Methods: Twenty-two people who get $33.09{\pm}10.73$ as average were evaluated by leg length analysis and X-ray findings. After measuring innominate measurement(IM), femur head line. distance between S2 and posterior superior iliac spine(PSIS). ilium shadow measurement(ISM), major axis of obturator foramen(MaF), minor axis of obturator foramen(MiF) and distance between off centering measurement and symphysis pubis, those were analyzed. Results: 1. In assessment of posterior rotation malposition ilium(PI), it was showed the best coincidence between leg length analysis and X-ray analyzed by 1M in supine position(11 cases, 50.5%). 2. In assessment of inflare, coincidence index between leg length analysis and X-ray were not good($4.00{\pm}3.03$ cases, $18.15{\pm}13.82%$). And leg length analysis were not sensitive. 3. On the whole, coincidence index between leg length analysis and X-ray were not good(best: 1 case, 45.5%; worst: 11 cases, 50.0%). Conclusions: Results form this investigation showed the relationship of leg length analysis and X-ray according 10 positions and valuation bases on diagnosis of pelvic malpositions. This results are expected to contribute to establish method of assessment in diagnosis of pelvic malpositions.

• Korean Journal of Agricultural Science
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• v.12 no.1
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• pp.22-30
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• 1985

Protoplasts of Pisum sativum L. were isolated and cultured from leaf mesophyll tissue. The successful yield of protoplast was obtained in an enzyme solution of 2% 'Onozuka R-10' and 2 % 'Macerozyme R-10' contained 6mM $CaCl_2{\cdot}2H_2O$ within 4 hours. They were divided in B5 culture medium supplemented with 2mg/l kinetin, 1mg/l 2, 4-D and 0.2% Difcobacto agar. Divisions of the protoplasts were continued and led to colony formation for 1 months. The colony from protoplasts of pea mesophyll tissue was formed to callus after subculture in a medium contained macronutrients and amino acids of BII medium and micronutrients and vitamins of B5 medium, and also supplemented with 2mg/l kinetin 2mg/l NAA.

• Journal of the Korean Society of School Health
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• v.9 no.1
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• pp.43-53
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• 1996

This paper was performed to comparative study with the children's body strength status of Ethnic Korean in China and Korea. The subjects of this study were the students of each elementary school located in a rural and a urban areas in China. To compared the level of their body strength status, we investigated to the students of 2 elementary schools as comparatives group on Kojae Area in Korea. We used students' physical record in the school. The contents of the study were the body weight, the chest circumstance, and the body height of the subjects. To make out the level of the students' physique, we measured by Rohrer Index output through above body height and body weight of them. The results of this study were as follows; 1. In the case of Ethnic Korean in China, the average body weight(kilogram) is $28.94{\pm}6.68$ in male $28.51{\pm}7.58$ in female. Comparatively, the average body weight in the case of Korean is 31. $99{\pm}7.23$ in male and $31.74{\pm}7.82$ in female. The average body height of Ethnic Korean is inferior about 2-5 Kilograms to that of Korean. 2. The average chest circumstance (centimeter) is $63.51{\pm}5.21$ in male $63.05{\pm}5.87$ in female of Ethnic Korean, $65.54{\pm}6.43$ in male and $64.57{\pm}7.81$ in female of Korean. Compared to between two group, the average chest circumstance of Ethnic Korean is inferior about 2-4 centimeters to that of Korean. 3. The average body height (centimeter) of Ethnic Korean is $135.28{\pm}8.96$ in male $134.82{\pm}9.74$ in female, and that of Korean is $136.68{\pm}9.12$ in male and $136.10{\pm}9.92$ in female. Like the preceding below results, the average body height of Ethnic Korean is inferior about 2-5 centimeters to that of Korean. 4. Compared to the fullness degree of physique between two group using Rohrer Index, Ethnic Korean is thiner than Korean. 5. Temporary, in case of children from 10 to 12 years old, female is superior to male through the index contained of the body weight, the chest circumstance, and the body height. It seems that female and male had different maximum growth age.

• Horticultural Science & Technology
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• v.28 no.4
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• pp.648-655
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• 2010

This study is the first comprehensive report on the molecular cloning, structural characterization, sequence comparison between wild and mutant types, copy number in the genome, expression features and activities of a gene encoding 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) in Korean lawn grass ($Zoysia$ $japonica$). The full length cDNA of the EPSPS from Korean lawn grass ($zj$EPSPS) obtained from a 3' and 5' RACE method was 1540 bp, containing a 1176 bp ORF, a 144 bp leader sequence (5' UTR) and a 220 bp 3' UTR, which was eventually decoded 391 amino acid residues with a molecular mass of 41.74 kDa. The Southern blot detection of the $zj$EPSPS showed that the gene exists as a single copy in the Korean lawn grass genome. Sequence comparison of the $zj$EPSPS gene demonstrated that the glyphosate-tolerant mutant (GT) having a Pro-53 to Ser substitution in the gene seems to have a preferred binding activity of the enzyme to phosphoenol pyruvate(PEP) over glyphosate, which allows the continuous synthesis of aromatic amino acids in the shikimate pathway. From the Northern blotting analysis, the $zj$EPSPS was found to be highly expressed, with continuous increase until 36 hours after 0.5% glyphosate treatment in both wild and mutant samples, but 1.5-fold higher EPSP synthase activity was observed in the tolerant mutant when exposed to the glyphosate treatment. The molecular information of the $zj$EPSPS gene obtained from this study needs to be further dissected to be more effectively applied to the development of gene-specific DNA markers and zoysiagrass cultivars; nevertheless, the glyphosate-tolerant mutant having the featured $zj$EPSPS gene can be provided to turfgrass managers for weed problems with timely adoptable management options.

• Journal of Aquaculture
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• v.3 no.2
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• pp.155-165
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• 1990

The albinic phenomenon of flat-fish (Paralichthys olivaceus) was investigated by measuring protein content, tyrosinase activity, amino acid composition, and contents of vitamin A and C. These materials in the flat-fish feed-stuff were also tested. The amount of skin protein was higher than that of muscle in normal flat-fish. Catechol and L-dopa oxidase activity did not differ between normal and albinic flat-fish. The free amino acid of skin in normal flat-fish was 7.5 times that in albinic one. Sulfur-containing amino acid in normal flat-fish was also 6.3 times that in albinic ones. Vitamin A was not detected in both of flat-fish. The content of vitamin C in normal flat-fish was 7.8 times that in albinic one. The contents of protein, sulfur-containing amino acid and vitamin C in micro-encapsulated feed (one commercial feed in Japan) were the highest among the feed-stuff used in this experiment. The melanin formation of flat-fish skin was affected by substrates such as aromatic amino acid and cofactor such as sulfur amino acid.

• Korean Journal of Cognitive Science
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• v.14 no.4
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• pp.21-31
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• 2003

This paper reports our experimental study with Korean-Chinese (=KC) bilinguals as compared with Korean monolinguals. We aim to find KC bilingual speakers' sentence processing strategies, and the interaction between the Ll and U2 grammars in bilingual development. To this end, we recruited 166 subjects of all age groups from age 3 to adult in the Korean autonomous community in Yanji, China, and did a classical subject/actor identification test, where subjects are supposed to pick out the subjects/actor of both sensical and nonsensical sentences (cf. Liu, Bates & Li, 1992). We compared our results with our previous work on monolingual Koreans, and found out that KC bilinguals rely on word order as well as anumacy; that KC bilinguals make use of morphology at age 10 as compared with age 5 for monolinguals; and that KC bilingual adults rely on animacy and word order as well as morphology, while monolingual Korean adults rely solely on morphology for sentence interpretation. Given that animacy and word order play an important role in the Chinese grammar, our finding lends support to the backward transfer which Liu, Bates & Li (1992) propose for early bilingualism.