• Korean Journal of Social Welfare
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• v.50
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• pp.235-263
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• 2002

The present study is designed to explore restructuring direction of the old-age income maintenance system and development direction of the Seniority Pension Scheme(SPS) in Korea. While the SPS is trifling scheme with tiny benefit amount and small budget, the SPS has important role that function as only public income maintenance scheme for both the low income class and the excluded from public pension and public assistance at present stage because of immature National Pension. This study starts with the research question why serious mis-matching problem between needs and resources in old-age income maintenance system occur. Thus this study explores fundamental change direction of the old-age income maintenance system which is coincide with further situation change(demography, labour market, family structure). Also this study explores desirable SPS's development direction as taking into account relation with other public old-age income maintenance system. This paper suggests basic direction of old-age income maintenance system as follows: principle of universal and individual security; principle of sustainability; principle of equity. Under general principle, this paper also proposes largely two development scenario of the SPS. The one is to maintain present transitional and provisional scheme with trying scheme's substantiality. The other is to change into permanent old-age income maintenance scheme for the excluded public pension and public assistance. At this point it is the public pension's role that the SPS's development direction is determined. If the public pension keep one pension per one earner as present system, non-contribution pension as present SPS should maintain continuously. However, if the public pension reorganize into basic pension of one pension per one person and earning-related pension, the SPS should be managed temporarily until mature of public pension. Therefore whether the public pension play basic security role for all elderly or not will determine the SPS development direction.

• Journal of Embryo Transfer
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• v.30 no.3
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• pp.149-159
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• 2015

This study was designed to know the possibility in repeat uses of elite donor cows for getting mass production of OPU-derived embryo production (OPU-IVP). Ultrasound transvaginal ovum pick-up (OPU) performed in 6 Korean native cows was aged 4 to 10 years old. The aspiration of immature oocytes for OPU derived embryo was carried out 2 times per week, and OPU-IVP of $1^{st}$ period was carried out 22~48 sessions from each donors. And the break time for OPU-IVP of $2^{nd}$ period after $1^{st}$ OPU from each donors were 2~25 months. The OPU-IVP of $2^{nd}$ period each donors conducted total 15~65 times for 2~8 months by an ultrasonographic, was guided follicular aspiration system. The average numbers of collected oocytes, grade 1 + grade 2(G1+G2) oocytes and cleavage embryo from $1^{st}$ period OPU-IVP were significantly differences between donors (p<0.05). Total collected oocytes of donor D were significantly higher compared with donors of A, B, C, E and F (average 17.0 per session vs. 11.2, 10.1, 8.5, 10.2 and 9.6; p<0.05) and also oocytes of G1+G2 were significantly higher compared with r A and D and subsequently to donors of B, C, E and F (average 7.9 and 8.5 per session vs. 5.0, 2.7, 6.0 and 1.6; p<0.05). Cleavage rate of donor D was significantly higher compared with donors of A, B, C, E and F (average 13.1 per session vs. 10.1, 9.1, 6.9, 8.9 and 6.7; p<0.05). The average numbers of OPU-IVP for $1^{st}$ period was significantly higher from donors of B, D and E than those from donors of A, C and F (average 6.5, 7.1 and 6.5 per session vs. 3.5, 4.2 and 2.8; p<0.05). The possibility investigation of $2^{nd}$ OPU-IVP was carried out after 2~25 months rest periods from $1^{st}$ period OPU session. Total average numbers of collected oocytes, cleavages and blastocyst development rates were significantly higher from $1^{st}$ period OPU compared with $2^{nd}$ period one (p<0.05). The OPU-IVP efficiency by break for more embryo production from elite cow was analysis comparing without rest of donor A, under 6 months rest period as B and over 6 months rest period as C and then the average numbers of collected oocytes, cleavages and blastocysts were significantly higher from A group (11.8, 9.5 and 5.2 per session) than those from B and C groups (7.9, 6.2 and 2.6 vs. 9.2, 7.5 and 3.9, p<0.05), and also C group was significantly higher than B group. In conclusion, $1^{st}$ period OPU-IVP was more efficient compared with $2^{nd}$ period repeated uses of donor, and the break times for additional production of embryo on donor were needed more than over 6 months after $1^{st}$ period OPU-IVP. This repeating uses of elite donor cows given more emphasis for getting the opportunity on mass production of elite cow OPU-IVP embryo should be increased G1+G2 possibility of genetic improvement of livestock within short period.

• Korean Journal of Poultry Science
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• v.16 no.2
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• pp.91-100
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• 1989

This study was conducted to observe 1) the changes of cellular association in seminiferous tubles from 2 to 8 weeks of age, and 2) the cycle phenomena of seminiferous epithelia at 14 weeks of age in Japanese quail. Total 80 birds were examined at a week interval from 2 to 8 weeks, and 14 weeks of age. The results were summarized as follows： 1) The body and testis weights showed most prominent increase during 4 to 5 weeks and 6 to 8 weeks of age respectively. And also the diameters of seminiferous tubles were abruptly enlaged during 6 to 8 weeks of age. 2) Genocytes in the seminiferous tubles were still in existence at 3 weeks of age, however they did not come out after 4 weeks of age. Spermatogonia, primary spermatocytes and spermatids made their first arpearances in the seminiferous from 3, 4 and 6 weeks of age, respectively. Spermatozoa were observed for the first time at 7 weeks of age, but full spermatogenic activity was completed from 8 weeks of age. 3) At 14 weeks of age, the average weight at testis was 3.7g and its ratio to the body weight was approximately 3.0 percent. And at this age, average diameter of seminiferous tubules was 192.08 $\mu\textrm{m}$, and average numbers of spermatogonia, spermatocytes, spermatids and spermatozoa within the cross section of seminiferous tubules were 7.74, 40.81, 28.42, 104.55 and 105.98, respectively. Spermatogonia and spermatid were classfied into 2 and 3 types, respectively. 4) At 14 weeks of age, the cycle of seminiferous epithelium could be divided into S stages with following characteristics. (1) Stage I： Seminiferous tubules showing type I and II spermatids. (2) Stage II： Seminiferous tubules showing type III spermatids only. (3) Stage III： Immature spermatozoa gathered near the sertoli cytoplasm. (4) Stage IV： Forming a bundle of 15-20 spematozoa. (5) Stage V： Spermatozoa bundle leaving the sertoli cytoplasm into lumen of the seminferous tubule. 5) Usually 2-3 stages of the seminiferous epithelium cycle were concurrently appeared within a tubular cross section, and frequency of each stage from I to V within cross section of seminiferous tubules were 11.91%, 27.03%, 27.96%, 19.04% and 17.98%, respectively.

• Korean Journal of Poultry Science
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• v.42 no.3
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• pp.247-256
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• 2015

There are approximately 1,500 broiler farms in Korea, each raising 55,000 birds. Ninety-five percent of the farms are contracted with Integration Company. According to the Korean broiler performance index, broilers in Korea are marketed at 32 days with 1.52 kg of body weight. In contrast, the market age and body weight of broilers are 47 days/2.8 kg in the United States and 42 days/2.5 kg in Europe. Because of the younger market age of the Korean broiler, the pre-starter feed is important. Chicks exhibit poor absorption of dietary nutrients up to 7 days after hatching due to an immature digestive system and low enzyme secretion rate and activity. At the beginning of hatching, chicks obtain their nutrients from the egg yolk sac. It is highly recommended that chicks, after consuming the nutrients in the egg yolk sac, are given supplemented pre-starter feed to increase early growth rates and improve the performance of broiler production. Pre-starter nutrient requirements are not expressed in NRC, so Korean feeding standards for poultry and commercial breeding companies determine the nutrient requirements of pre-starter broiler chickens. Three approaches are followed to formulate specially designed pre-starter feeds for broiler chicks: (i) selective use of raw materials, (ii) proper standards of nutrient supply, and (iii) application of feed additives such as exogenous enzymes. In the selection of raw materials, those with high digestibility can be used. The absorption rate of carbohydrates in grains can be increased through feed processing at high temperature and high pressure. Soy proteins and fish meal can also be added as protein sources. As an energy source, vegetable oils are preferred over animal fats because of the former's high digestibility. It is suggested that the levels of proteins and amino acids are higher in pre-starter feed than in starter feed. With regard to energy, the sources of energy are more important than the levels of energy in feed. Feed additives such as exogenous enzymes can be used to improve nutrient digestibility. In addition, organic acids and plant extracts can be used as alternatives to animal growth promoters to stimulate immunity and prevent diseases. The growth performance of broilers is affected by various factors, such as management and disease control, in addition to the nutritional strategy; however, nutritional strategies play an important role in improving the productivity of broilers. Therefore, nutritional strategies, along with management and disease control, are required for improving the productivity of broilers in Korea.

• Radiation Oncology Journal
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• v.24 no.1
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• pp.51-57
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• 2006

Puroose: We examined whether intratumoral (i.t.) administration of dendritic cells (DCs) into a treated tumor could induce local and systemic antitumor effects in a mouse tumor model. Methods and Materials: C57BL/6 mice were inoculated s.c. in the right and left thighs with MCA-102 fibrosarcoma cells on day 0 and on day 7, respectively. On day 7, the tumors (usually 6 mm in diameter) on the right thigh were heated by immersing the tumor-bearing leg in a circulating water bath at $43^{\circ}C$ for 30 min; thereafter, the immature DCs were i.t administered to the right thigh tumors. This immunization procedure was repeated on days 7, 14 and 21. The tumors in both the right and left thighs were measured every 7 days and the average sizes were determined by applying the following formula, tumor $size=0.5{\times}(length+width)$. Cytotoxicity assay was done to determine tumor-specific cytotoxic T-lymphocyte activity. Results: Hyperthermia induced apoptosis and heat shock proteins (HSPs) in tumor occurred maximally after 6 hr. For the local treated tumor, hyperthermia (HT) alone inhibited tumor growth compared with the untreated tumors (p<0.05), and furthermore, the i.t. administered DCs combined with hyperthermia (HT + DCs) additively inhibited tumor growth compared with HT alone (p<0.05). On the distant untreated tumor, HT alone significantly inhibited tumor growth (p<0.05), and also HT + DCs potently inhibited tumor growth (p<0.001); however, compared with HT alone, the difference was not statistically significant. In addition, HT + DCs induced strong cytotoxicity of the splenocytes against tumor cells compared to DCs or HT alone. Conclusion: HT + DCs induced apoptosis and increased the expression of HSPs, and so this induced a potent local and systemic antitumor response in tumor-bearing mice. This regimen may be beneficial for the treatment of human cancers.

• Journal of the Korean Society of Radiology
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• v.4 no.1
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• pp.31-35
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• 2010

Recently, the incidents of direct or indirect radiation exposure due to increase of use of radiation or radioisotope are on the increase in medical and industrial circles. If cells are irradiated, free radicals are created through biological process, and cells are directly or indirectly damaged. This research intends to explore into the effect of saponin at the level of cell (in vitro) and entity (in vivo), using red ginseng extract "saponin", as radioprotective agent. In the experiment implemented at the level of cell (in vitro), degree of cell activity was measures by adding mouse mesenchymal stem cells "C3H/10T1/2 cells" into red ginseng extract "saponin(0, 0.05, 0.2, and 0.4 g/L)", and then the optimal concentration of saponin influencing cells was calculated, in 24, 48, 72, and 96 hours after gamma irradiation at the optimal concentration of saponin, each cell survival rate was observed through XTT assay. The best time period of cultivation for the optimal activity of C3H/10T1/2 cells was as 48 hours, and the degree of optimal activity was shown at 0.05 g/L. In 48 hours after irradiation of 5 Gy to C3H/10T1/2 cells at 0.05 g/L, the degree of activity of cells increased by 10%. In the experiment implemented at the level of entity (in vivo), red ginseng extract "saponin" at a dose of 100 mg/kg/day was injected into the abdominal cavity of six-week immature mouse for two weeks. Right after the last abdominal injection, total body irradiation of gamma rays was carried out at a dose of 5 Gy and 10 Gy. And after irradiation, the blood sample was taken, and then the number of red corpuscles was counted. In result, the decrement of experimental group treated with red ginseng extract "saponin" was 2.3 times larger than that of control group. In view of the results so far achieved, it was revealed that red ginseng extract "saponin" has a radiation exposure protection effect in the experiment implemented at the level of cell (in vitro). In case of animal experiment, the decrement of number of red corpuscles decreased. Finally, it is necessary to carry out more various researches continuously.

• Journal of Life Science
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• v.17 no.12
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• pp.1766-1770
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• 2007

We describe here a case of malignant mixed osteogenic tumor of the mammary gland with alveolar carcinomatous appreance. A firm, 2 to 2.5cm (in diameter) mass under the 5th nipple, showing the structure of extraosseous osteogenic sarcoma, was removed from the left 5th mammary gland of 12-year-old female dog. When investigated under the microscope, the osteoid material undergoing mineralization was surrounded by numerous scattered osteoblasts and a few osteoclastic cells throughout the osteoid tumorous stroma. The osteoid lesions were continuous with hypercellular myoepithelial cells of a very immature character with several mitotic figures. In addition, there were also carcinomatous tubules and alveoli, with invading cells into peripheral stroma, surrounded by myoepithelial cells in the mammary gland. In these lesions, emanating cords of tumor cells appear to be continuous with the myoepithelial cell layer of a duct. The presence of all these cell types suggests the existence of a common malignant origin, the stem cell being differentiated into epithelial carcinomatous and mesenchymal sarcomatous chondral and osteogenic tissues.

• Korean Journal of Environmental Biology
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• v.35 no.4
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• pp.526-532
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• 2017

Development, survival, and reproduction of brown planthopper (BPH) Nilaparvata lugens $St{\aa}l$ (Hemiptera: Delphacidae), were studied in laboratory at $25{\pm}2^{\circ}C$, $65{\pm}5%$ RH and a 16L : 8D hours photoperiodism on five rice cultivars of: Dongjin 1ho, Chungchungbyeo, Jangseongbyeo, Chinnongbyeo and Jungmo 1045. BPH nymphs successfully survived on all rice cultivars, although survival rate was lowest on Jangseongbyeo (36.0%). Developmental time of immature stages ranged from $11.7{\pm}0.59d$ on Jungmo 1045 to $12.8{\pm}0.59d$ on Chinnongbyeo. Reproductive period and female longevity were longest on Dongjin 1ho, Chinnongbyeo and Jungmo 1045 while highest fecundity of N. lugens being observed on these three rice cultivars. Highest and lowest net reproductive rates were calculated on rice cultivars, Jungmo 1045 and Jangseongbyeo, respectively. Mean generation time was the longest on rice cultivar Dongjin 1ho. Respective descending order of intrinsic rates of population increase were on Jungmo 1045, Chinnongbyeo, Dongjin 1ho, Chungchungbyeo and Jangseongbyeo. These population parameters showed that N. lugens can successfully survive and reproduce on Chinnongbyeo and Jungmo 1045.

• The Journal of Art Theory & Practice
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• no.8
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• pp.33-58
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• 2009

This paper examines four genre paintings on the subject of child education by Jean-Baptiste-Sim${\'{e}}$on Chardin(1699-1779). The Governess, The Diligent Mother, Saying Grace, and The Morning Toilette garnered critical attention after they were exhibited in the Salon from 1739 to 1741. After the exhibition, the paintings were made into prints and frequently sold to members of the bourgeois class in Paris. The iconographical details of Chardin's genre paintings have, thus far, been compared to Dutch genre pictures of the seventeenth century. Further, most studies conducted on Chardin's paintings focus on formal analysis rather than the historical and social contexts. Through attempting social-contextual readings of Chardin's educational series, this paper argues that the significance of Chardin's painting series of child education lies in his representation of the ideal French bourgeois family and the standard of early childhood education in the eighteenth-century French Enlightenment period. In each of the four child education paintings, Chardin depicted a mother with children in a domestic space. Even though this theme derives from traditional Dutch genre paintings in the seventeenth century, the visual motifs, the pictorial atmosphere and the painting techniques of Chardin all project the social culture of eighteenth century France. Each painting in the child education series exemplifies respectively the attire of a French gentlemen, the social view on womanhood and the education of girls, newly established table manners, and the dressing up culture in a 'toilette' in eighteenth century France. Distinct from other educational scenes in previous genre paintings, Chardin accentuated the naive and innocent characteristics of a child and exemplified the mother's warmth toward that child in her tender facial expressions and gesturing. These kinds of expressions illustrate the newly structured standard of education in the French Enlightenment period. Whereas medieval people viewed children as immature and useless, people in the eighteenth century began to recognize children for their more positive features. They compared children to a blank piece of paper (tabula rasa), which signified children's innocence, and suggested that children possess neither good nor bad virtues. This positive perspective on children slowly transformed the pedagogical methods. Teaching manuals instructed governesses and mothers to respect each child's personality rather than be strict and harsh to them. Children were also allotted more playtimes, which explains the display of various toys in the backgrounds of Chardin's series of four paintings. Concurrently, the interior, where this exemplary education was executed, alludes to the virtue of the bourgeois's moderate and thrifty daily life in eighteenth century France. While other contemporary painters preferred to depict the extravagant living space of a French bourgeoisie, Chardin portrayed a rather modest and cozy home interior. In contrast to the highly decorated living space of aristocrats, he presented the realistic, humble domestic space of a bourgeois, filled with modern household objects. In addition, the mother is exceptionally clad in working clothes instead of fashionable dresses of the moment. Fit to take care of household affairs and children, the mother represents the ideal virtues of a bourgeois family. It can be concluded that the four genre paintings of child education by Chardin articulate the new standards of juvenile education in eighteenth century France as well as the highly recognized social virtues between French bourgeois families. Thus, Chardin's series of child education would have functioned as a demonstration of the ideal living standards of the bourgeois class and their emphasis on early childhood education in the French Enlightenment period.

• Journal of Bio-Environment Control
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• v.30 no.3
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• pp.237-243
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• 2021

The objective of this study was to evaluate the effect of stem number on plant growth, fruit quality, and yield of sweet peppers grown in greenhouses under supplemental lighting in winter. The seedlings were transplanted at 3.2 plants·m^-2 on October 26, 2020, and started supplemental lighting with 32 high pressure sodium lamps for 16-hour photoperiod from December 1, 2020 to May 25, 2021. Stems were differently trained with 2 and 3 numbers after branching nodes were developed. In the final harvest, the plant height was significantly shorter in the 3 stem-plants than in the 2 stem-plants. The number of nodes per stem and the leaves per plant were increased in the 3 stem-plants than in the 2 stem-plants, while the leaf area was less affected. There were no significant differences in the dry mass of leaves, stems, and immature fruits between the 2 and 3 stem-plants. The fruit fresh weight and fruit dry weight in the 3 stem-plants were decreased by 17% and 12% at 156 days after transplanting (DAT), and by 17% and 15% at 198 DAT compared to those in the 2 stem-plants, respectively. The marketable fruit rates were 93.6% and 95.4% in the 2 and 3 stem-plants, respectively. The total fruit yield in the 3 stem-plants was increased by 30.2% as compared to that in the 2 stem-plants. We concluded that the 3-stem-training cultivation positively affected the total fruit yield by sustaining adaptive vegetative growth of the plants. This result will help producers make useful decisions for increasing productivity of sweet peppers in greenhouses.