• Journal of Periodontal and Implant Science
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• v.23 no.1
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• pp.97-108
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• 1993

One of the important initial events required for periodontal regeneration is the attachment and subsequent spreading of periodontal ligament cells on the root surface. The purposes of this study is to investigate the attachment and spreading pattern of human periodontal ligament cell on the surface of glass slides. After establishment of a cell line of the primary cell culture from the periodontal ligament of 1st premolar teeth which were extracted for the purpose of orthodontic treatment, author dispersed the cells at $5{\times}10^3\;cells/ml$ into the each 35mm culture petri-dish containing 2 glass slides. To observe the morphological changes of the cells which attached to the surfaces of glasses at every designed time schedule, author used the inverted phase contrast microscope and scanning electron microscope. During the whole experiment culture condition was at $37^{\circ}C$, 100% Humidity, 5% $CO_2$ gas incubator. The following results were obtained. Periodontal ligament cells showed spherical outline and started to attach to glass surface by basal sytoplasmic extension after 10min in culture. After 30min in culture, periodontal ligament cells were attached to glass surface by well - developed filopodia which protruded from the lamellipodia. The cell surface is covered with bubble-like structures and occasional microvillus can be seen with diffculty among these structures. After 1.5hr in culture, peridontal ligament cells shhowed radially well-spread cytoplasm and the nucleus was centered on its cytoplasm. Unspread central region of the cell was covered with numerous microvilli. The change of cell attachment and spreading pattern was manifest at 6hr in culture. At this time, periodontal ligament cell showed elongated outline and an oval-shaped nucleus. After 12hr in culture, periodontal ligament cells showed more stretched fibroblast-like appearance with polarity. Two long lamellipodia can be seen around the both terminal ends of cells. After 24hr in culture, periodontal ligament cells showed spindle shapes and an oval-shaped nucleus was slanted toward one side of the cell.

• Journal of Food Hygiene and Safety
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• v.22 no.1
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• pp.29-36
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• 2007

The using frequency of processed foods and dietician's perception against management of food service at 98 food service institutions located in Jeollabuk-Do were surveyed. Food service institutions included 13 hospitals,38 schools,40 enterprises, and 7 others. Single menu (75.5%) with two (33.7%) or three (57.1%) side dish was offered. In addition, the offering ratio of boiled water and spring water was 37.8 and 32.7%, respectively. The processed foods with high using frequency were kochujang (1.19), sesame oil (1.22), and doenjang (1.30), but that of leek, onion, Chinese cabbage, and radish were 4.95, 4.62, 4.60, and 4.26, respectively. Dietician's major affairs in all type of food service institutions were cooking (64.3%), purchase (48.0%), and personnel managements (39.8%). Dieticians, however, had a low perception against safety and nutrition management. Therefore, in order to prevent the outbreak of food-borne diseases, we estimated that the education and the conversion of dietician' perception against safety and nutrition management were needed.

• Journal of Preventive Medicine and Public Health
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• v.30 no.3 s.58
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• pp.609-622
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• 1997

Nitrogen dioxide $(NO_2)$ has been regarded as one of the main elements among air pollutants, and we measured $NO_2$ levels of near gas range, kitchen, living room and outdoor on 489 apartments in Pusan area. $NO_2$ were sampled by using Palmes tubes (diffusion tube sampler) during August 16-25, 1995 (summer) and January 15-29, 1996 (winter), respectively. Authors wanted to know comparison of $NO_2$ levels in summer and winter, $NO_2$ levels categorized by variables, and variables affected to $NO_2$ levels. According to this study, we conducted to establish the degree of indoor-outdoor air pollution of urban apartments in Korea and methods to reduce indoor air pollution. The results of this study were summarized as follows: 1) Mean $NO_2$ levels of near gas range, kitchen, living room, and outdoor were $25.9{\pm}10.0ppb,\;23.3{\pm}8.0ppb,\;19.9{\pm}6.1ppb,\;and\;19.0{\pm}6.0ppb$ in summer, and $34.5{\pm}16.8ppb,\;28.2{\pm}13.4ppb,\;25.3{\pm}12.5ppb,\;21.8{\pm}9.8ppb$ in winter, respectively. 2) Mean $NO_2$ levels according to the floor levels were not significantly different in summer, and in winter, $NO_2$ levels were decreased as the floor levels were increasing, but those were increased above 16th floor. 3) Variables showing significant correlation(p<0.05) with $NO_2$ levels were as follows; Summer: floor level, family size, number of family during a meal, number using gas range during rice cooking per day, and natural ventilation. Winter: floor level, family size, number of person who have been respiratory disease in a house, number of family during a meal, total number of meals, and number using gas range during rice or side-dish cooking per day. 4) We suggest that the methods of reducing indoor $NO_2$ levels are ventilation during cooking, complete combustion, decreasing number and time of cooking, and substitution of fuels.

• The Korean Journal of Archival Studies
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• no.59
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• pp.207-275
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• 2019

This archiving project of the survivors of suicide was done with the survivor supporting team of the Seoul Suicide Prevention Center. The survivor supporting team was operating a Self-help Support Group for the emotional support of the survivors of suicide. A Self-help Support Group is a place for the survivors of suicide to regularly meet and share their suffering by talking of topics hard to discuss elsewhere. As the Self-help Support Group progressed members who acted as the leader of the group appeared. They formed an essay group that writes together. Two fathers who lost their sons, two mothers who lost their daughters, a mother who lost her son, a wife who lost his husband. The essay group met each week in a place facing Sajik Park. Through the windows that took up the whole side of the room, evening was coming in. The things that happened during the day went away towards Inwang mountain following the setting sun. Ten people (six members of the essay group, three from the survivor support team, a historian for unique conversation) sat around a table, facing each other. "Now, what shall we do?" History for unique conversation is a time that archives life by sharing conversations. At times a complete stranger, and other times people who share their ordinary lives sit around together (3-9 people, sometimes about 15). On the table there is coffee, bread, fruits and salads, and sometimes a dish someone heartily prepared. When a bottle of wine is placed on the table, each takes a glass. Morning, afternoon, the time the evening is welcomed in, late night. It does not matter which. For six months, 3 hours when meeting every week, 6 hours when at every other week. A room where the ambience is like that of a kitchen where sunlight enters, or a cozy living room is the best location. However, there are many times when it is held in a multipurpose room in the suburbs where many meetings are held, or in a classroom of a school. The meeting place is decided according to different situations of the time. There are no participation requirements as it is said to be for themselves to write down according to archiving form while looking back their lives thoroughly, and they are the only ones to stop themselves. The archives landscape from far away would seem like trying to do some talking. However, when going into a microscopic situation one must leave themselves to the emotional dynamics. It is because it archives the frustration and failures one experienced through life. A participator of history for unique conversation must face the sufferings of their life. The archiving project took place in 2013 to 2014. Many years have passed. Has the objective distance for archiving the situation of that time been secured? That may be uncertain, but I will speak of a few stray thoughts on archiving while depicting the process and method of operation.

• Korean Journal of Heritage: History & Science
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• v.44 no.4
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• pp.86-111
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• 2011

Wan is a tableware in which boiled rice or soup, side dish are put, and it is a representative model which shows the development of personal tableware. From the establishing period of Hanseong Baekje, the form of wan which is Jung-do Style(中島式) Plain Pottery of previous period Proto-Three Kingdoms Period was succeeded to, but wan is produced and used as a wan baked in the kiln, which is far development of the producing technique including hardness and clay. By and large, the size of $0.3{\sim}0.4{\ell}$ was the majority and the production technique of wan which used carefully selected soft quality clay are largely confirmed to be two methods which are, first, basic method by which on a clay tablet on the rotating table, clay band is accumulated and moulding is finished, and second, the new method which had the same basic moulding as that of basic method but in the last stage takes wan off the rotating table and reverse it to trim the bottom and remove the angle of flat bottom. The former, basic production method is the classical production method since wan of Jung-do Style Plain Pottery and wan was produced and used for all periods of Hanseong Baekje. On the other hand, the latter is the production method obtained through form imitation of China made porcelain flowed into through interchange between Baekje and China, and through comparison with Chinese chronogram material it is estimated to have been produced and used after middle of 4th century. Therefore it can be known that the Baekje people's demand for China made articles was big and imitation pottery was produced and used with Baekje pottery. In addition, bowl with outward mouth are confirmed in multiple number in Lakrang(樂浪) pottery wan and it is assumed that wan was the form produced under the influence.

• Korean Journal of Plant Resources
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• v.37 no.2
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• pp.149-160
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• 2024

In Korea, potatoes have served as a side dish, but their role as snacks, such as chips or French fries, has recently gained traction. While there is a high demand for processing potatoes, there remains a dearth of research on the impact of double cropping, particularly during autumn, on processing quality. Therefore, this study was conducted to determine the effects of different spring potato cultivation periods on growth, yield, and processing quality during autumn cultivation. Following spring planting, harvest was carried out four times: 70 days, 80 days, 90 days, and 100 days. Subsequently, autumn cultivation was carried out in Gangneung and Seocheon regions using these seed potatoes. Results showed an increase in above-ground emergence rate with shorter spring growing period. When seed potatoes with a spring cultivation period of 80 and 90 days were grown in the autumn in the Gangneung region, the stem length was 47.2 to 48.9, which was greater than that of other treatments. However, stem number and leaf color (SPAD) showed no significant differences across cultivation periods. The number of tubers, tuber weight, yield, and marketable yield did not vary significantly with cultivation periods but described clear cultivar dependent differences. The tuber weight of the Saebong cultivar in Gangneung and the Eunseon cultivar in Seocheon was superior. The starch content peaked at 7.9% when seed potatoes grown for 80 days in the spring were harvested after autumn cultivation in the Gangneung region, but there was no significant differences in the Seocheon region. Glucose content showed a clear difference depending on the cultivation period, increasing with longer spring cultivation period during autumn cultivation. In conclusion, as a result of the effect of the spring potato cultivation period on the growth, yield, and processing quality of tubers when cultivating potatoes in double-cropping, the differences depending on the cultivation period were insignificant, while cultivar-based disparities were pronounced. The Eunseon cultivar exhibited robust above-ground growth and yield, while the Saebong cultivar demonstrated excellent processing quality.

• Journal of Nutrition and Health
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• v.47 no.1
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• pp.77-88
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• 2014

Purpose: This study analyzed the foodservice satisfaction and menu preference of 506 high school boarding students in Jeju surveyed from July 2-30, 2012 with the aim of providing basic data for improving the quality of boarding food-service management. Methods: The data were analyzed using descriptive analysis, t-test, and Pearson's correlation coefficients, using the SPSS Win program (version 12.0). Results: Regarding satisfaction with dormitory foodservice, the satisfaction scores for service and hygiene were 3.46 (out of 5 scales), whereas the score for menu quality was 3.26 points. In terms of satisfaction by meal, dinner showed the highest score, at 3.70 (out of 5 scales). The satisfaction scores for breakfast were significantly higher in girls (3.36) than boys (2.93). Regarding intake of meals provided, dinner showed the highest score, at 3.96 (out of 5 scales), whereas breakfast showed the lowest score, at 3.63 points. Intake of lunch and dinner was significantly higher in boys (4.12, 4.17, respectively) than girls (3.72, 3.76, respectively). Regarding the requirements of subjects for dormitory foodservice, 43.4% of subjects selected improvement of food taste and 36.6% of girls chose menu diversity. In terms of menu preferences for main dishes, the students preferred noodles (4.06) and one-dish cooked rice (3.92) to cooked rice (3.66). The subjects preferred beef rib soup (4.10) and Kimchi stew (3.99) in soups and stews. With regard to the menu preferences for side dishes, steamed foods showed the highest score, at 3.95 (out of 5 scales), whereas seasoned foods showed the lowest score, at 2.89 points. The students preferred beef, pork, and chicken to fish and vegetables. The students preferred dessert the most with fruit juices (4.52). Bread and rice cake were more favored by girls, showing significant differences between boys and girls (p < 0.05, p < 0.01, respectively). Conclusion: Development of a systematic nutrition education program that can encourage practice of proper eating habits is needed. In addition improvement of the quality of boarding school meals through the service of various menus is needed.