• Development and Reproduction
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• v.16 no.4
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• pp.279-287
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• 2012

We investigated the changes in plasma sex steroid hormones, testosterone (T), estradiol-$17{\beta}$ ($E_2$), 17,$20{\beta}$-dihydroxy-4-pregnen-3-one ($17{\alpha}20{\beta}P$), 11-ketotestosterone (11KT) and cortisol levels from ribbed gunnel, Dictyosoma burgeri in associated with annual reproductive cycle. The gonadosomatic index (GSI) of females increased from November, peaked in February and decreased rapidly from March. The GSI of males also increased from November, peaked in January and then decreased gradually. In females, $E_2$ levels increased and remained high from December to February. The levels of T showed a similar tendency and correlated ($r_s$=0.898, p<0.01) with $E_2$ levels. The levels of $17{\alpha}20{\beta}P$ increased rapidly in February ($4.78{\pm}1.01ng/ml$) and peaked in July ($5.08{\pm}0.65ng/ml$). Cortisol level was peaked in March and correlated with $17{\alpha}20{\beta}P$ levels ($r_s$=0.696, p<0.01). In males, the levels of T was peaked in January and then decreased rapidly. The levels of 11KT were remained high from October to January. On the other hand, the levels of $17{\alpha}20{\beta}P$ fluctuated during reproductive cycle. These results suggest that plasma sex steroids in ribbed gunnels have annual periodicity, and that cortisol may involve in maturation of females.

• Korean Journal of Child Studies
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• v.11 no.1
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• pp.15-28
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• 1990

The purpose of this study was (1) to investigate and order the levels of parental authority concepts established by Damon, and (2) to investigate the relationship between the development of parental authority concepts and the child's age and sex. The subjects of this study were 120 children from an elementary school in Seoul. There were 40 subjects (20 males and 20 females) in each of three age groups: 8-, 10-, and 12- year-olds. The subjects were interviewed individually using Damon's(1977) open-ended questions concerning family rules. Responses to the assessment questions were coded as positive or negative, and responses to the judgement concept questions were coded into 6 levels. Statistical analysis of obtained data was by percentage, Spearman correlation using an ordinal scale, two-way analysis of variance, and Duncan test. The results showed that (1) the developmental levels of parental authority concepts established by Damon conformed to an ordinal scale, and (2) the development of parental authority concepts was related to child's age but not to child's sex.

• Korean Journal of Child Studies
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• v.35 no.3
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• pp.157-176
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• 2014

A total of 378 $4^{th}$ and $5^{th}$ grade elementary school students (194 boys and 184 girls) participated in a study investigating the direct and indirect effects (through self-esteem and/or achievement motivation) of children's perceptions of parental expectations on school happiness. First, parental expectations did not have a direct effect on children's levels of school happiness. Second, parental expectations did not have an indirect effect on children's school happiness through self-esteem. Children who perceived higher levels of parental expectations showed higher levels of self-esteem, but the path from children's self-esteem to school happiness was not significant. Third, parental expectations had an indirect effect on children's levels of school happiness through achievement motivation. Children who perceived higher levels of parental expectations showed higher levels of achievement motivation, and children with higher levels of achievement motivation reported higher levels of school happiness. Finally, parental expectations indirectly influenced children's school happiness through self-esteem and achievement motivation. These findings suggest that both environmental and individual factors need to be considered together to more comprehensively explain children's levels of school happiness.

• International Journal of Computer Science & Network Security
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• v.22 no.7
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• pp.283-293
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• 2022

One of the important areas of state policy in the socio-economic and cultural development of the country is cultural diplomacy. It contributes to the information dissemination about the country, strengthens interstate relations, and forms a positive image. Through cultural diplomacy, we achieve a positive perception of the world community of the country, determined by its place in the modern system of international relations. The aim of the study is a comparative analysis of cultural diplomacy opportunities for sustainable development at different levels of public relations, as well as the impact of cultural diplomacy opportunities on the indicators of the Global Sustainable Competitiveness Index and the Global Sustainable Development Index. Regarding the results of the research on the impact of cultural diplomacy opportunities on the indicators of the Global Index of Sustainable Competitiveness and the Global Index of Sustainable Development, four groups are identified among the countries of the European Union: countries with a very high level of sustainable competitiveness and sustainable development; countries with a high level of sustainable competitiveness and sustainable development; countries with low levels of sustainable competitiveness and sustainable development.

• International Journal of Industrial Entomology and Biomaterials
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• v.43 no.2
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• pp.85-93
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• 2021

Silkworm pupae have been utilized as a food source and have high-quality proteins and fatty acids. However, studies on the nutritional composition of pupae according to their variety, developmental stage, and sex have not been conducted. In this study, the nutritional composition of four Korean silk varieties (Baegokjam, BG; Goldensilk, GS; Juhwangjam, JH; and YeonNokjam, YN) were analyzed according to developmental stage and sex. The main ingredient of the pupa was protein, and the protein levels were higher in females than in males. Fat levels were high in males and increased in YN and GS during the late stage but decreased in BG. Fiber content rapidly increased in the late stages, and the lowest content was observed in BG. The pupae contained all essential amino acids, which were detected at higher ratios in females with a high protein content. Fatty acids had a different predominance depending on the variety. Oleic acid level was high in BG, linoleic acid and linolenic acid levels were high in GS, and palmitic acid and stearic acid levels were high in JH. In the mineral analysis, zinc was dominant in BG, whereas calcium and iron levels were relatively low. Zinc level was low in GS, and calcium and magnesium levels were high in JH. Potassium, sodium, magnesium, and phosphorus levels were low in YN. The silkworm pupae showed differences in components according to their variety, sex, and developmental stage; therefore, selecting a variety suitable for its purpose is necessary.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.3
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• pp.308-313
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• 2015

A $3{\times}3$ factorial study was conducted to investigate the effects of dietary protein and lipid levels on the growth, feed utilization and innate immunity of red seabream Pagrus major. Nine diets consisting of three protein levels (42%, 46% and 50% crude protein) and three lipid levels (10%, 14% and 18% crude lipid) were formulated. Triplicate groups of red seabream were fed the experimental diets to apparent satiation (5-6 times a day, from 08:00 to 18:00 h at 2-h intervals) for 10 weeks. At the end of the feeding trial, the weight gain and specific growth rate of fish fed P46L14 (46% protein and 14% lipid), P50L10 (50% protein and 10% lipid) and P50L14 (50% protein and 14% lipid) were significantly (P<0.05) higher than those of fish fed P42L18 (42% protein and 18% lipid). The feed conversion ratios (FCR) of the fish were affected by dietary lipid levels (P<0.039), but not dietary protein levels. The FCR tended to increase with increasing dietary lipid levels from 10% to 18% with the 46% and 50% protein levels. The weight gain, protein efficiency ratio, specific growth rate, feed intake and survival of fish were not affected by either dietary protein or lipid levels. Myeloperoxidase activity in the group fed P50L14 (50% protein and 14% lipid) was significantly higher than that in the group fed P42L10 (42% protein and 10% lipid) or P50L18 (50% protein and 18% lipid). However, the myeloperoxidase activity of fish was not affected by either dietary protein or lipid level. The fish fed P46L14 (46% protein and 14% lipid) and P46L18 (46% protein and 18% lipid) showed significantly higher superoxide dismutase activity than did the fish fed P46L10 (46% protein and 10% lipid), P50L10 (50% protein and 10% lipid) of P50L18 (50% protein and 18% lipid). In conclusion, the optimum protein and lipid levels for the growth and feed utilization of juvenile red seabream were 46% and 14%, respectively, and the optimum dietary protein to energy ratio was 27.4 g/MJ.

• Korean Journal of Animal Reproduction
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• v.20 no.3
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• pp.315-322
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• 1996

The study was conducted to determine the optimal glucose, superoxide dimutase(SOD) and catalase levels during the in vitro culture of porcine oocytes matured and fertilized in vitro for morulae and blastocyst development. Oocytes were cultured for 0~8 days in TCM-199 medium supplemented with 20% FCS, different glucose, SOD and catalase levels. The results are summairzed as follows ; 1. The in vitro developmental rates of porcine oocytes cultured in TCM-199 medium containing 0.1, 0.3, 0.5, 1.0, 3.0 mM glucose levels 0~3 and 0~8 days after insemination were 22.8, 24.2, 21.9, 20.0, 12.1 and 21.9, 26.7, 25.0, 22.6, 16.7%, respectively. 2. The in vitro developmental rates of porcine oocytes cultured in TCM-199 medium containing 100, 200, 300, 500 $\mu\textrm{g}$/ml SOD levels 0~3 and 0~8 days after insemination were 16.7~23.3 and 16.7~25.0%, respectively. High levels of SOD(500 $\mu\textrm{g}$/ml) significantly reduced the rates of molurae and blastocysts stage(P<0.05). 3. The in vitro developmental rates porcine oocytes cultured in TCM-199 medium containing 100, 200, 300, 500 $\mu\textrm{g}$/ml catalase levels 0~3 and 0~8 days after insemination were 18.8~26.7 and 19.4~28.1%, respectively, and there was significant differences on the development to the molurae and blastocysts stage among the cumulus cells and glucose levels.

• Journal of Korean Society for Quality Management
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• v.30 no.1
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• pp.47-60
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• 2002

Recently, the range of using Internet in business is expanding rapidly. And through Internet, companies are strengthening both their internal efficiency and their external competitive advantage in the market. In recent years, building and managing companies' web sites are becoming unavoidable tasks in business. Such a trend is becoming more imperative in business over the world. There is a great deal of research in progress to study the cases of companies with increasing performance from the use of their Internet web sites. But it is considered that there has not been enough of study in the area of levels of Internet application in business especially in strategic areas and application levels among countries. This research is in the same line of the research that was carried out on such topics in 1999. study in 1999 showed that there are significant differences in the usage levels of Internet in business between countries with long history of using Internet and those who are not. The 1999 study also suggested the model on development stages of Internet usage in business. This study is the continuation of the 1999 research and used two years of data to compare and analyze the trend of the Internet development stages in leading corporations in Korea, U.S.A., and Japan. This study found that there have been significant developments in the ability to use Internet in business in three countries. The differences in Internet usage level in each stage among different countries are compared and analyzed in this study.

• Journal of Embryo Transfer
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• v.32 no.4
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• pp.267-274
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• 2017

Alpha lipoic acid (ALA) is a biological membranes compound. As the antioxidant, it decreases the oxidized forms of other antioxidant substances such as vitamin C, vitamin E, and glutathione (GSH). To examine the effect of ALA on the in vitro maturation (IVM) of porcine oocytes, we investigated intracellular GSH and reactive oxygen species (ROS) levels, and subsequent embryonic development after parthenogenetic activation (PA). Intracellular GSH levels in oocytes treated with 50uM ALA increased significantly (P < 0.05) and exhibited a significant (P < 0.05) decrease in intracellular ROS levels compared with the control group. Oocytes matured with 50 uM of ALA during IVM displayed significantly higher cleavage rates (67.8% vs. 83.4%, respectively), and higher blastocyst formation rates and total cell number of blastocysts after PA (31.6%, 58.49 vs. 46.8%, 68.58, respectively) than the control group. In conclusion, these results suggest that treatment with ALA during IVM improves the cytoplasmic maturation of porcine oocytes by increasing the intracellular GSH levels, thereby decreasing the intracellular ROS levels and subsequent embryonic developmental potential of PA.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.3
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• pp.369-374
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• 2012

A $3{\times}2$ factorial experiment was conducted to determine the effects of dietary protein and lipid levels on the growth and body composition of juvenile far eastern catfish. Six diets were formulated to contain three levels of protein (20%, 30% and 40%) and two levels of lipid (9% and 17%). Triplicate groups of fish (initial body weight of 7.6 g) were hand-fed to apparent satiation for 66 days. Final mean weight was improved with increasing dietary protein and lipid levels, and the highest final mean weight was observed in fish fed the 40/17 (% protein/% lipid) diet. No significant difference was observed in final mean weight for fish fed between 30/17 diet and 40/9 diet. Feed efficiency of fish fed the diets containing over 30% protein levels with 9% and 17% lipid levels were significantly higher than those of fish fed the 20% protein levels. Feed efficiency of fish fed the 30/17 diet was not significantly different from that of fish fed the 40/9 diet or 40/17 diet. Feed efficiency and protein efficiency ratio of fish fed the 20% protein diets with 17% lipid level were significantly higher than those of fish fed 9% lipid diet. Daily feed intake of fish tended to decrease with increasing dietary protein and lipid levels. Moisture content of whole body in fish fed the 9% lipid diets was significantly higher than that of fish fed the 17% lipid diets at the same protein level, but the opposite trends were found for crude lipid content. Significant effects of dietary lipid were observed for most fatty acids, according to their relative values in the diets. The results of this study suggest that the protein requirement for maximum growth of juvenile far eastern catfish may be higher than 40%, and an increase of dietary lipid level from 9% to 17% can improve growth and feed utilization.