• Journal of the korean academy of Pediatric Dentistry
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• v.48 no.4
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• pp.437-448
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• 2021

The purpose of this study is to analyze morphological characteristics of maxillary primary molar's root and root canal. 268 children aged 3 - 7 years (175 boys, 93 girls) who had CBCT (152 children) and 3D CT (116 children) taken in Seoul National University Dental Hospital from January 2006 to April 2020 were included. The number of roots and root canals were analyzed in 1002 teeth without any root resorption or periapical pathologies. Curvature, angulation, length of root and root canal, as well as cross-sectional shapes of the root canal were analyzed in 218 teeth. By using Mimics and 3-Matics software, volume, surface area, and volume ratio of root canal was analyzed in 48 teeth. More than half of maxillary primary molars have 3 roots and 3 root canals. The degree of symmetry of root canal type was about 0.63 (Cohen's kappa coefficient). The most frequent shape of roots and canals was linear in 1^st primary molars and curved in 2^nd primary molars. Angulation, length of root and root canals was the largest on palatal roots. Most teeth showed ovoid or round shapes at apex. The largest root canal volume, surface area, volume ratio was found in the palatal roots.

• Korean Journal of Culture and Social Issue
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• v.27 no.4
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• pp.561-584
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• 2021

This study was conducted to classify 601 Korean adults into latent classes according to their love types and identify the differences in depression and find variables that affect the latent classes classification. As a result of the latent class analysis, the latent group for love types of Korean adults were classified into the L-H (7.7%) group, which showed the highest level of all three factors of intimacy, passion, and commitment, and the L-MH (33.6%) group, which all three factors were higher than the average, the L-M (39.8%) group with the mean of all three factors, the L-ML (14.6%) group with all three factors lower than the mean, and the L-L (4.3%) group with the lowest all three factors. Also, as a result of ANOVA, the L-MH group was psychologically healthier and more adaptive than the L-ML group. As a result of multinomial logistic analysis, females were more likely to belong to L-M, L-ML and L-L groups than males. In addition, singles were more likely to belong to the L-M and L-ML groups than those who were married. Also, the higher the anxiety attachment level, the higher the likelihood of belonging to the L-M, L-ML, and L-L groups than the L-H and L-MH groups, the L-ML and L-L groups than the L-M groups, and the L-L group rather than the L-ML groups. However, age, neuroticism, and emotional regulation did not affect the classification of latent classes. This study is meaningful in that it identified the various latent classes for the love types of Korean adults more three-dimensionally and suggested the possibility of differential interventions according to the characteristics of each group.

• Korean Journal of Culture and Social Issue
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• v.22 no.4
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• pp.487-522
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• 2016

The main purpose of this research is to investigate Korean adolescents' perception of stress experiences, and related social support. To this end, adolescents were asked about stress events, as well as stress symptoms, in their lives. Also, the adolescents were asked about the people that provided social support and the types of social support provided. The participants were 952 Korean adolescents (Primary 219; Middle 280; High 212; University 241). Among the four measures (stress events, stress symptoms, social supporters, and types of social support), the measure of stress symptoms yielded a reliability of Cronbach α=.88, while the remaining three measures yielded an inter-judger reliability of 89.6%, Kappa=.87. The results were as follows. First, for stress events, the most frequent responses were related to Academic Achievement, followed by Career/Job, Family Relations, Friend Relations, Lack of Capacity, and Financial Difficulties. For high-school students the most frequent responses were related to Academic Achievement, while for university students Career/Job. Second, for stress symptoms there were significant differences among the groups, in that the high-school students showed the highest level of symptoms, while primary school students the lowest. Third, for social supporters, the most frequent responses were related to Friends, followed by Myself, Parents, Teacher, Siblings, and Seniors/Juniors. As the groups aged (from primary to university), support from Friends and Seniors/ Juniors increased, while support from Parents decreased. Fourth, for the types of social support, the most frequent responses were related to Emotional Support, followed by None, Advice, Supporter Directly Solved Problem, and Talked with Me. The highest frequencies of responses were found for Emotional Support among all groups. As the groups aged (from primary to university), Advice increased while Supporter Directly Solved Problem decreased.

• (The) Research of the performance art and culture
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• no.41
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• pp.219-255
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• 2020

This article was triggered by Victor H. Mair's book 'Painting and performance'. The book explained that Buddhist paintings are common in the area where Buddhism was spread, and there are also performances using them. And although it has nothing to do with Buddhism, it has been shown that this form of performance can be global. However, the problem was not 'Korea'. It was because there was no record or transmission of the corresponding performance soon. In this situation, the landing method of Samcheok stable temple was announced in 2018. On the one hand, the academic community is very pleased, but on the other hand, it is troubled. The worries are summed up as 'synchronic and diachronic universality'. Is the landing method inherited from the Samcheok stable temple a unique type of temple? Otherwise, it is a question of whether it has been passed down or is it universal at the national level. However, prior to this essential question, we do not yet know the full picture of the stable landing method. So this article was prepared to show the overall outline of the stable landing method. There is a 'picture' in common throughout the landing method, and understanding how to operate it in various ways is the first step in understanding the landing method. There are five repertoires (which are called main halls) that are considered important, and more than that. What these repertoires have in common is the narrative structure of a Buddhist character. In this narrative, the most important thing is the revised figure, and it was the earthly method to inform the contents of the revised figure in various ways. In the case of Byeonsangdo, which serves as a clue to the narrative, there was a problem that could not be seen in the evening without light, which required special design. It is the way of shadow play and Yeongdeung. In other words, there are three types of performances in the landing method. The first is the method of using reparation, and the second is the method of using shadow. The third is the way of eternity. This method is not a selection based on the contents of the repertoire, but a selection based on the performance environment. If there is light and you can see the picture, use reparation. However, in the evening, it was impossible to see it dark (when there was no electricity in the past). The use of the visual method as a tool in this method is to confirm the transition to a visual culture that is a step further from the level of culture. Moreover, unlike the epic narrative, the power of the implied image provided an opportunity for viewers to experience the mystery of Buddhism through emotional stimulation.

• Research in Plant Disease
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• v.29 no.1
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• pp.23-38
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• 2023

The fire blight caused by Erwinia amylovora (Ea) is a devastating disease of Rosaceae plants, including commercially important apple and pear trees. Since the first report in Korea in May 2015, it has been spreading to neighboring regions gradually. Host plants can be infected by pollinators like bees, rainfall accompanied by wind, and cultural practices such as pruning. Many studies have revealed that wild Rosaceae plants such as Cotoneaster spp., Crataegus spp., Pyracantha spp., Prunus spp., and Sorbus spp. can be reservoirs of Ea in nature. However, wild Rosaceae plants in Korea have not been examined yet whether they are susceptible to fire blight. Therefore, the susceptibility to fire blight was examined with 25 species in 10 genera of wild Rosaceae plants, which were collected during 2020-2022, by artificial inoculation. Bacterial suspension (10⁸ cfu/ml) of Ea type strain TS3128 was inoculated artificially in flowers, leaves, stems, and fruits of each plant species, and development of disease symptoms were monitored. Moreover, the presence of Ea bacteria from inoculated samples were checked by conventional polymerase chain reaction. Total 14 species of wild Rosaceae plants showed disease symptoms of fire blight, and Ea bacteria were detected inside of inoculated plant parts. These results suggest that wild Rosaceae plants growing nearby commercial apple and pear orchards in Korea can be Ea reservoirs, and thus they should be monitored regularly to minimize the damage by Ea infection and spreading.

• Journal of Food Hygiene and Safety
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• v.38 no.2
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• pp.46-54
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• 2023

In this study, we examined the residual amounts of formaldehyde in hygiene products to determine the safety of these products in Gyeonggi-do. Formaldehyde is among the harmful substances that may remain within certain hygiene products. On the basis of an analysis of formaldehyde in a total of 222 items (6 disposable paper straws, 9 disposable paper napkins, 21 toilet papers, 13 disposable dishcloths, 16 disposable paper towels, 32 wet wipes for food service restaurants, 25 disposable cotton swabs, and 100 disposable diapers), we detected traces in three wet wipes for food service restaurants (1.87 to 4.45 mg/kg), which is approximately 9% to 22% of the standard level (20 mg/kg). We established that all the hygiene products assessed in the study met the individual standards for formaldehyde, thereby confirming that safe products are being distributed. In the standards and specifications for hygiene products, the formaldehyde test method is regulated for application with respect to three categories based on the type of product. The samples used in this study were of types for which method 1 or method 2 is applied, and the limits of detection, limits of quantification, linearity, and recovery rates were reviewed to verify the validity of each test method. When method 2 was applied, we experienced interference when performing analysis at a wavelength of 412 nm, which was associated with the influence of impurities in some samples of disposable cotton swabs and disposable diapers. Consequently, in these cases, the results were compared after analysis using method 1. By comparing the results obtained using method 2 with those obtained using method 1, the latter of which were unaffected by the interference of impurities, we were able to detect formaldehyde at low concentrations. These findings accordingly highlight the necessity to standardize the formaldehyde test method for future analyses.

• Journal of the Korean Society of International Agriculture
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• v.31 no.3
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• pp.249-254
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• 2019

'Japonica 6' is a japonica rice variety developed from a cross between 'MS11', the beginning variety adaptable to tropical region, and 'IR86743-28-1-4', an elite line of high yield and good plant type by a Korea(RDA)-IRRI cooperative breeding program at IRRI in 2017. The growth duration of 'Japonica 6' is 121 days from sowing to harvest. It is 10 days later than that of the check variety 'MS11'. The culm length of 'Japonica 6' is 70 cm, and 1,000-brown rice grain weight is 26.7 g. It has a shorter culm and a larger grain. size than that of MS11. 'Japonica 6' is moderately resistant to blast disease but susceptible to bacterial blight, tungro virus and plant hoppers. The milled rice recovery rate of 'Japonica 6' is improved than that of 'MS11'. The head rice rate of 'Japonica 6' is significantly higher than that of 'MS11'. Yield of 'Japonica 6' is averagely 3.59 MT/ha of milled rice in 5 areas of the Philippines. The 'Japonica 6' was registered in Philippines and would be adaptable to the diverse regions of tropical Asia (Registration No in Philippines. BPI-NSIC-2017-Rc 484SR).

• 한국노년학
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• v.39 no.3
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• pp.467-484
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• 2019

The purpose of this study is to explore latent classes of longitudinal medical expenses of older people and to analyze its predictors and its effects on subjective health. Among participants of the Korean Health Panel, the sample of this study includes 1,119 people who is 65-year-old or older and reported their medical expenses for nine consecutive years. The analyses were conducted in three steps. First, Growth Mixture Model (GMM) was applied to find distinct subgroups showing similar patterns in medical expenses. The results showed four groups which were classified as high medical expenditure maintenance group, medical expenditure increase group, low medical expenditure maintenance group, and medical expenditure reduction group. Second, the multinominal logistic regression found that the presence of spouse, economic participation, the number of chronic diseases, and the type of health insurance were significant predictors of latent classes in medical expenses. In particular, the greater the number of chronic diseases, the higher the likelihood of belonging to the high medical expenditure maintenance group. In addition, medical benefit recipients are more likely to belong to the low medical cost maintenance and medical cost reduction groups. Third, multiple regression analysis revealed that the older people in the groups with low or reducing expenses reported better subjective health than people with higher expenses. This study has its meanings in exploring the heterogeneity in longitudinal medical expenses among older people and its predictors and its associations with health outcome. The results of this research provide background information in establishing public health policy for older people.

• 한국노년학
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• v.39 no.3
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• pp.517-529
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• 2019

The study was conducted on the impact of employment types middle and old age group of wage earner on life satisfaction and analyzed by dividing it into variables in the employment types and demographic characteristics. Based on the data for the 12th year of the Korea Welfare Panel Study, 1,244 respondents who answered that the main types of economic activities were 'full-time, temporary, daily wage earners' or 'self-help labor, public labor, and elderly empolyment program in public sector.' among 4,341 people over 55 years of age under the age of 75 as of 2017 standard. The survey covered 1,244 people. By age group, 826 people aged 55-64 (middle-age group) and 418 people aged 65-74(old-age group). Middle age group showed that education level, spouse, health condition, beneficiaries of basic livelihood and average monthly income variables were the factors that influence the satisfaction of life. But The type of employment did not significantly affect. Old age group showed that the higher education level, in spouse with-living or spouse death, the better health condition is perceived, the less experience of beneficiaries of basic livelihood, the higher average monthly income, the more satisfied life is. The survey also found that old-aged people who participate in "self-help labor, public labor, and elderly employment program in public sector" are also found to be more satisfied with their lives. According to these results, policy for the old age group should be focused on hunting and expanding of employment program in public sector for the elderly. In order to boost life satisfaction of the elderly, more intensive vocational education and employment training should be provided.

• Journal of the Korean Society of International Agriculture
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• v.31 no.4
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• pp.428-436
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• 2019

As the main objective of rice breeding programs, rice eating quality is one of critical factors directly determining the market price and the consumer preference. However, the genetic complexity of eating quality and the difficulty in accurate evaluation often constrain improvement of the eating quality in rice breeding programs. In addition, given that the rice eating quality of current cultivars has already reached some high-level, diversifying of genetic resources are demanded more than ever to improve the rice eating quality. In this study, we developed a recombinant inbred lines (RILs) population derive from Wandoaengmi6, a japonica-type Korean weedy rice with high eating quality and a high degree of glossiness of cooked rice. Year-to-year correlations between the traits in three years were shown normal distribution for major agronomic traits and physicochemical characteristics. After evaluating tested traits related to eating quality procedure, a total of ten lines were ultimately selected from the population. Increasement of the taste of cooked rice (TA) and the overall eating quality (OE) were confirmed in the selected lines, which are caused by alleles derived from Wandoaengmi6 without any linkage drag. These results indicate that the utility of wide genomic resources in Korean landrace could be of application in various rice breeding programs and countermeasure to contribute to properly response to climate change.