• Journal of the Korean Society of Child Welfare
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• no.54
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• pp.79-111
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• 2016

The purpose of this study was to examine the structural models in which early cumulative risk factors affect children's language(indicated by expressive vocabularies) and social development(indicated by peer competence) at age 3 thorough their effects on the home learning environment. To examine the hypothesized models, the data of 1,725 families from the second and the fourth waves of the Panel Study of Korean Children was used. Correlation analysis and structural equation modeling were conducted to test the models. First, the cumulative risk factors at age 1 and 3 were highly correlated, implying the stability of the risk factors over time. The more cumulative risk factors at age 1 predicted the lower level of the home learning environment at age 3, which, in turn, was significantly related to both language and social development at age 3. However, the early cumulative risk factors did not directly influence later developmental outcomes. Moreover, the cumulative risk factors at age 3 were directly related to the child's language development, but neither social development northe home learning environment. In addition, the mediational role of the home learning environment (i.e., cumulative risk factors at age 1${\rightarrow}$home learning environment${\rightarrow}$language and social development) was statistically supported. In conclusion, the early cumulative risk factors in infancy indirectly predicted children's development at age 3 through the home learning environment. The practical implications for the early intervention and support for the families with infants who are experiencing multiple risk factors were discussed.

• Journal of Convergence for Information Technology
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• v.9 no.12
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• pp.62-70
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• 2019

The study used cross-lagged path modeling to examine the longitudinal associations between self-esteem and community spirit among adolescents. This is a longitudinal study designed to examine the developmental changes of adolescents' self-esteem and community spirit in Korea. This study used the data collected by the Korean Children and Youth Panel Survey (KCYPS) from 2014 through 2016. Participants were surveyed from the 5^th grade to the 7^th, which belonged to the 1^st elementary school cohort panel of the KCYPS. To be used as the data of this study, children should have all information at 3-time points: the 5^th grade; 6^th grade; 7^th grade. The collected data were analyzed with PSAW 18.0 and AMOS statistical program. The participants in this study were 903 males (51.6%) and 847 females (48.4%). The level of self-esteem was 3.29±.51, 3.19±.55, and 3.15±.57 point at 5^th grade, 6^th grade, and 7^th grade each. The level of community spirit was 3.12±.52, 3.09±.59, 3.15±.55 point respectively. Community spirit from elementary school to middle school is consistently predicted by previous self-esteem. Likewise self-esteem has a significant predictive effect on subsequent community spirit.

• Korean journal of applied entomology
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• v.60 no.4
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• pp.479-487
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• 2021

This study investigated the life history of the plum sawfly Monocellicampa pruni Wei, 1998 through field observations and laboratory experiments. M. pruni is a univoltine, complete metamorphosis species with five instars at the larval stage. Adults emerge from the soil around mid-March when Japanese plum trees are in their flowering period. The adults deposit one (rarely two) egg(s) under the epidermis layer of the calyx. After hatching, the larva soon burrows into the fruitlet, consumes the endocarp and remains inside the fruit within its four-time moulting transitions before reaching full growth. At maturity (in May), the larva leaves the infested fruitlet through an exit hole and burrows into the soil at a depth of 2 - 11 cm for spinning its cocoon and hibernates until the next spring as the larval form. Under laboratory conditions (T = 20℃; RH = 40 - 60%), the male lived for a slightly shorter period than the female, 6.03 ± 0.40 and 7.55 ± 0.45 days, respectively. A female could produce 30.29 ± 4.50 eggs in her lifespan. In the field, the duration of the egg was approximately 10 - 11 days and that of the larva was approximately 31 - 34 days.

• Ecology and Resilient Infrastructure
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• v.8 no.4
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• pp.281-289
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• 2021

Commercially used disposable cups undergo fragmentation in the environment and become microplastics (MPs). These MPs can be ingested by aquatic organisms and cause a range of adverse effects. We assessed the acute and chronic toxicity of disposable cup-derived MP fragments in Daphnia magna. MP fragments were identified as a polyethylene terephthalate (PET) fragment with a size of 33.18 ± 7.76 ㎛. The presence of three additives including 1- Propanone. 1-phenyl-3-[2-(phenylmethoxy)phenyl]-, p-Xylene and ethylbenzene was analyzed from MP fragments. The 48 h acute toxicity revealed that 20 % of immobilization and mortality were found at the highest concentration of PET MP (200 mg L^-1). The 21 d chronic toxicity revealed that PET MP fragments significantly (p < 0.05) more reduced survival rate (31 %), total offspring (52 %) in D. magna compared with control group. The developmental abnormality of offspring (3.5%) by PET MP fragments was significantly (p < 0.05) higher than control groups (0.3%). These results are possibly induced by gut blocking by ingestion of MP fragments and their longer retention time. These findings indicate that the fragmentation of disposable cups (PET polymers) into small-sized MP fragments pose a significant ecological risk to aquatic organisms. Further studies are required to elucidate the underlying toxicity mechanisms.

• Korean Journal of Comparative Education
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• v.28 no.3
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• pp.243-263
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• 2018

In order to confirm the academic authenticity of comparative education, the academic methodology which is also appropriate for the historical arrangement is the history. In this sense, this article focuses on the study of comparative education from the viewpoint of history of education and aims for a tentative approach to comparative education history. In every discipline, it is essential to organize the history of the discipline both for those majoring in it and for the development of the discipline itself. The conclusions obtained from this study are as follows. First, in general, the method of studying comparative education includes not only 'comparative studies' but also 'regional studies', but it can add academic depth through the study of time series called 'comparative education history'. Second, the developmental process of the comparative education can be classified into four stages; the first stage is 'the pre-history' of the comparative education, the second stage is the 'embryo stage', the third stage is the 'establishment stage', and the fourth stage is the 'development stage'. Especially, in the era of globalization, the academic potential of comparative education is even higher, so it is possible to add an 'expanding period'. Third, it is necessary to understand the 'comparative education history' in order to secure the academic identity of the comparative education study. It is expected that it will be possible to more easily confirm the perspectives and issues of comparative education in the future, together with a good conceptual understanding of comparative education.

• Journal of the korean academy of Pediatric Dentistry
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• v.46 no.3
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• pp.239-246
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• 2019

The purpose of this study was to examine dental complications and to evaluate the effects of initial treatment age, treatment modalities, and treatment duration on the disorder after radiation and chemotherapy in pediatric cancer patients. For 93 children with clinical and radiographic data, the number of teeth, the morphology of teeth, the shape of the roots, and development status of the dentition were evaluated. Dental development disorders were found in 61.3% of the children. The mostly found abnormality was root deformity with the prevalence of 31.2%. In children submitted to the therapy before the age of 6, the number of missing teeth (p = 0.029) and microdontia (p = 0.003) were greater compared to the children who started to receive the treatment after the age of 6. The combination of radiation and chemotherapy showed significantly greater incidences of missing teeth (p = 0.030), microdontia (p = 0.046), and root deformity (p = 0.009) when compared with the sole application of chemotherapy. When the children were submitted to anticancer therapy for 18 months or longer duration, greater number of missing teeth (p = 0.032), microdontia (p = 0.011), root deformity (p = 0.025), and total number of teeth affected (p = 0.036) were observed compared with duration less than 18 months. The number of dental abnormalities increased when the children were treated at earlier ages, with combination of radiation and chemotherapy, and for longer period of time.

• Korean Journal of Comparative Education
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• v.28 no.5
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• pp.71-90
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• 2018

The purpose of the study was to analyze the various outcomes of parent competency enhancement project for children's education by Daegu Metropolitan Office of Education in Daegu, Korea. For this, the study explored the developmental process of parent educational competency enhancement policy and the main contents of parent competency enhancement project for children's education. Based on this, the study analyzed the outcomes of parent competency enhancement project for children's education. The main results are as the followings. First, a system for enhancing parents' competency for children's education by administering parent competency enhancement project for children's education was established. Second, personnel for parent education by administering parent competency enhancement project for children's education was cultivated. Third, basic courses and in-depth courses using the needs of parent who is educational consumer by administering parent competency enhancement project for children's education were developed. Finally, the result of evaluation by student, parent, and teacher and educational expert indicated that they showed high satisfaction about parent competency enhancement project for children's education. However, it showed that it is necessary to make up the operational time and method and the profession of instructor and program and to support parent considering various types of school. The implications for the main results were discussed.

• Toxicological Research
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• v.35 no.3
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• pp.241-248
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• 2019

Pesticide exposure may induce biochemical alterations including oxidative stress and lipid peroxidation. However, in the context of developmental origin of health and disease, putative trans-generational effect of exposure to pesticides are insufficiently studied. We therefore aimed to evaluate the biochemical effect of gestational exposure to four pesticides on female Wistar rats and their offspring at adult age. We studied 30 female nulliparous Wistar rats divided into 5 equal groups. Group 1 served as the control group and received distilled water while group 2, 3, 4 and 5 received orally pesticide 1 (imidacloprid), pesticide 2 (chlorpyrifos), pesticide 3 (imidacloprid + lambda cyhalothrin) and pesticide 4 (oxamyl) respectively once daily throughout gestation at a dose equivalent to 1/10 lethal dose 50. The mothers were followed up until one month post gestation. The offspring were followed up from birth until adult age (12 weeks). In all animals at each time point we evaluated malondialdehyde (MDA), oxidative stress and liver function enzymes. There was similar variation of total body weight in all the groups during and after gestation. However, Female Wistar rats of the exposed groups had significant alterations in liver SOD (-30.8% to +64.1%), catalase (-38.8% to -85.7%) and GSH (-29.2% to -86.5%) and; kidney catalase (> 100%), GSH (> 100%). Moreover, MDA, alanine transaminase (ALT) and aspartate transaminase (AST) levels were significantly higher in pesticide exposed rats compared to the control group. Similar alterations in antioxidant enzymes, MDA and liver function enzymes were observed in offspring of treated rats evidenced at weaning and persisting until adult age. Exposure to pesticides causes oxidative stress and lipid peroxidation in exposed female Wistar rats and their offspring. The persistence in offspring at adult age suggests transgenerational adverse effects.

• Korean Journal of Child Education & Care
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• v.19 no.2
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• pp.101-116
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• 2019

Objective: The purpose of this study is to provide basic data on physical activity management plans for different developmental levels in infants. This study analyses the difference between support requests and the professional practical of evaluations, content selection, and physical activity management plans displayed by teachers of one and two-year-old infants. Methods: The subjects of the study were 221 teachers from child care centers throughout J-do to whom a questionnaire containing 51 questions was distributed. Collected data was verified with a chi-squared test and an independent samples t-test. Results: First, among variables of professional practical of physical activities, some factors including class size, class planners and leaders, the number of outdoor classes per week and requisite time, parts of related education plans, parts of content selection for physical activities, and parts of the evaluation of physical activities showed significant differences depending on the class. Second, among variables of support requests when implementing physical activities, some factors including methods of preparing physical activity plans, teaching -learning methods, evaluation methods, body expression activity programs, and parts of physical exercise in the standardized child care curriculum of refresher and extension courses showed significant differences depending on the class. Conclusion/Implications: This study discusses the effective management of refresher and extension courses as a way to improve physical activity management plans and teachers' support requests for infants aged 1 to 2.

• Korean Journal of Heritage: History & Science
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• v.38
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• pp.285-303
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• 2005

Through the excavated excellent articles of the Tang era, we have considered the building techniques and styles of a square pavilion, an octagonal pavilion, a miniature hill, a pond, etc., could read building techniques of the scenic structures on ancient literatures including records and additionally about their poetical life at that time and inquired into the arrangement, structure, building techniques, etc. of a miniature hill, a pond, a pavilion, a flowerplant, etc., on Nakyangmyungwonki. Thus, under the research on the private landscape architecture, especially the nobility gardening, around excavated excellent articles and literatures, 'A miniature hill(假山) and a pond for landscaping views formed the center of a garden, and additionally a pavilion was built and flowerplants were set. The miniature hill of laying stones and having a carven, steeping, stratifying, looking like dyed green and birds' singing among hills and eating water on the lakeshore${\ldots}$' was expressed. The pond of digging in the ground and conducting water had its water system developed. There were several kinds of pavilions such as 廳, 堂, 館, 亭, 臺, 樓, 閣, 榭, etc. As examples of landscaping plants, there were a bamboo, a lotus flower, a peony, aromatic trees a pine, a korean spindle tree, a big cone pine, an empress tree, a wild walnut, a peach, a plum, a Japanese apricot tree, an apricot tree, a chrysanthemum, arrowroot vines, etc. Thus, the garden of the Tang era, abundant, diverse and excellent, enjoyed the prime of the period of prosperity. Due to cultural exchange, it is supposed that the period of united Shilla of the same age would meet with the period of prosperity in the developmental history of Korea landscape, based on the nobility garden system '4 different dwelling-houses every season on a record "四節游宅"'.