• The Korean Journal of Zoology
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• v.30 no.2
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• pp.107-116
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• 1987

It is the purpose to investigate the physiological toxity and mutagenicity by heavy metal compounds such as potasium dichromate, sodium arsenite and selenium dioxide on the development of Drosophila melanogaster. These chemical compounds were highly toxic at every developmental stage of Drosophila. The relative values of fecundity, viability and developmental time obtained on food media containing 5 different levels of potasium dichromate (500, 600, 700, 800, and 900 ppm), also 5 different levels of sodium arsenite and selenium dioxide (10, 15, 20, 25 and 30 ppm). Resulting in the relative values of fecundity and viability generally decreased, on the contrary developmental time generally reduced as the concentration of chemicals in the food increased. A significant reduction in the fecundity was observed between 800 and 900 ppm (p<0. 01) on the potasium dichromate media, between 15 and 20 ppm (p<0. 05) on the sodium arsenite media, between 20 and 25 ppm (p<0. 02) on the selenium dioxide media. A significant reduction in the viability was observed between 700 and 800 ppm (p<0. 01) on the potasium dioxide media, between 25 and 30 ppm (p<0. 01) on the sodium arsenite media, between 20 and 25 ppm (p<0. 01) on the selenium dioxide media. The developmental time was significantly reduced between 800 and 900 ppm (p<0. 001) on the potasium dioxide media, between 15 and 20 ppm (p<0. 001) on the sodium arsenite media, and between 25 and 30 ppm (p<0. 01) on the selenium dioxide media.

• Journal of the Korean Home Economics Association
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• v.29 no.3
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• pp.153-174
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• 1991

The purpose of this study is to examine the leisure activities of housewives, to identify the factors that influence leisure activities, and to explore the factors contribute to their life satisfaction. So, this study analyses the effects of econo-demographic and socio-cultural variables and of leisure constraint factors on the leisure activities of housewives. And it deals with how these variables and the leisure activities influence life satisfaction of housewives. For these puoposes, 508 housewives residing in Seoul & Daegu were selected for interviews. For data analysis such statistical methods as ANOVA, t-test, Pearson's correlation, adn Multiple Regression Analysis can be summarised. The main findings of the research are as follows: 1. Leisure acivities are classified in Self-developmental, Home-oriented, Time-consuming, Social and Children-concerned types by the technique of factor analysis. The average particiation level was high in Time-consuming type, but low in Self-developmental type. 2. The participation level of leisure activities shows significant differences by selected variables: The Self-developmental type shows significant differences by housewife's education level, income, husband's occupation, role orientation, home management type and leisure constraints. And Children-concerned type was differed to number of family nember, number of children, age of housewife and age of housewife and age of the youngst child. 3. The preference level of leisure activities differ by housewife's education level, income, husband's occupation, home management type and leisure constraints in the Self-developmental and the Social type. And the preference level of Home-oriented leisure activities was high in the middle class of income and husband's occupation. 4. The preference and participation level of leisure activities show differences. And the variables affecting the differences were housewife's age, education level, home management type, role orientation, leisure constraint factors in the Self-developmental type, and were demographic variables such as number of family member, housewife's age in the Home-oriented type. 5. The variables which affected the level of life satisfaction independently were leisure space, income, the participation level of the Self-developmental and the Social type and the preference level of the Self-developmental type.

• Korean Journal of Child Studies
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• v.30 no.4
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• pp.173-189
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• 2009

This study investigated contextual characteristics and developmental functions of time spent alone in early adolescence. Participants were 107 6th grade elementary school students. The Experience Sampling Method was used to measure experiences of time spent alone. Findings were that : (1) 2.6% of an early adolescents' daily waking time was involuntarily spent alone and 14.8% was voluntarily spent alone. (2) Psychological states of voluntary time spent alone were more positive than those of involuntary time spent alone, and psychological states of voluntary time spent alone were not significantly different from those of time spent with family members or friends. (3) Experiences during voluntary time spent alone were related to adjustment, suggesting that time spent alone during early adolescence contributes to positive development.

• Journal of Agricultural Extension & Community Development
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• v.4 no.2
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• pp.407-413
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• 1997

Recently, the community developmental enthusiasm is activated and emerged with the varied developmental plans since the localization was implemented in Korea. But the anxious view of the environmental problems has been gradually heightened in the Environmentally Sound and Sustainable Developmental(ESSD). The local autonomy should listen to the public opinions because the people's anti-developmental movement could obstruct the development project in the community level. The Environment-friendly Rural Development Plan(EFRDP) pursues the development and the environmental preservation of the community at the same time. Therefore EFRDP reflects the local developmental intention and consideration of environmental preservation at the step of planning. Throughout the planning process the opinions of development and environmental preservation should be adjusted, the people's planning ability can be enhanced, and new creative alternative ideas will come out at times.

• Human Ecology Research
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• v.58 no.2
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• pp.255-266
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• 2020

This study observed and investigated the commute time of dual-earner couples from a family developmental perspective. It tested whether the household responsibility hypothesis was effective in explaining the gender gap in the commute time for these couples. I extracted 2,103 time diaries written by 1,266 matched couples from the 2014 Korean Time Use Survey data for this study. The sample was categorized by the age of the eldest child into four age groups of 0-6, 7-12, 13-18, and 19-29. Analytic results from ANOVA, Scheffé test, and OLS regression are as follows. First, husbands traveled longer hours to work than wives in all age groups, while the commute time of couples tended to increase along with the child' age. However, couples in the child group aged 7 to 12 had the shortest commute time. Second, domestic labor time of wives were negatively associated with the commute time, which appeared to support the household responsibility hypothesis. Third, in the child group aged 7 to 12, wives spent more time for work commute as their income increased; however, wives with traditional gender role attitudes had a shorter commute time in the child group aged 0 to 6. Forth, neither the wives' nor husbands' work characteristics were related to the wives' commute time; however, both wives' and husbands' work characteristics were related to the husbands' commute time. The findings suggest the possibility of spatial entrapment by working wives throughout the family life cycle due to household responsibilities, which provides implications for policy intervention in consideration of the gender gap in commute time for dual-earner couples.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 1998.07a
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• pp.63-65
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• 1998

생쥐의 초기발생과정에서 배아 세포질의 제거로 nucleus/cytoplasm ratio를 증가시켰을 경우, 발생과 gene expression에는 영향을 미치지 않았으나 형태형성은 촉진되었다. 또, nucleus/cytoplasm ratio의 변화 없이 발생후기의 cytoplasm으로 일부 치환된 배아에서 발생과 gene expression, 형태형성은 모두 촉진되었다. 이상의 결과로 보아 초기배아의 gene expression과 형태형성과정에서 일어나는 time schedule의 조절은 nucleus/cytoplasm ratio가 직접적으로 영향을 미치지 않고 난자와 배아 내에 존재하는 cytoplasm factor에 의해 조절 받으며, 특히 형태 형성의 time schedule은 cytoplasmic factor와 이들에 의해 조절되는 물질의 상대적인 농도에 의해 조절될 것으로 여겨진다.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 1998.07a
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• pp.53-54
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• 1998

햄스터 난자에서 관찰되는 SAC의 활동은 30mmHg 이내의 음압자극에 대하여 잘 관찰되었으며 단일통로의 크기나 open time에 따라 4종류로 구분될 수 있었다. SAC 활동은 PKA에 의하여 활성이 조절되었으며 수정 후 할구분할이 진행될수록 SAC 전도도가 작은 통로로 전환되어 발생 초기 SAC 활도양상이 특징적인 변화가 관찰되었다.

• Korean Journal of Childcare and Education
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• v.17 no.1
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• pp.19-37
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• 2021

Objective: This study aimed to explore the effect of the national preschool curriculum on children's development in Korea, focusing on teachers' daily practice. By comparing the effect of the teachers' curriculum practice to that of quantitatively measured free play, it tried to add practical implications beyond the statistical significance. Methods: Participants were 512 three-year-old children who participated in the Panel Study of Korean Children and their teachers. National curriculum practice and free play time at the age of three was put in the hierarchical linear regression models to discover children's developmental outcomes at the age of four, in domains of language, cognitive development, and social development. Results: Results demonstrated the significant positive influence of national curriculum practice on every domain of developmental outcomes. However, no facilitative influence of free play time was observed. Conclusion/Implications: The importance of teachers' practice of the national curriculum was emphasized. It was implied that the quantity of free play time itself did not assure the sound development of children. Policy implications were discussed regarding teacher practice and education.

• Proceedings of the KSAR Conference
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• 2004.06a
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• pp.257-257
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• 2004

The study was carried out to investigate the effects of morphology, reproductive cycle, incubation time and activation of oocytes on in vitro maturation of cat oocytes and development of IVM/IVF embryos. 1. When recovered from ovaries collected at different stages of the reproductive cycle (inactive, follicular and luteal stage), the developmental rates of oocytes to GV and MI stage were 72.5% and 27.5%, 57.5% and 7.5%, 62.5% and 17.5%, respectively. (omitted)

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2001.02a
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• pp.55-56
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• 2001

Gelatin zymograms of bFF and bS showed GA110 and 62 kDa gelatinses in adsition to several minor ones. Of these, GA110 gelatinase was abolished by treating bFF or bS with bOF and interestingly, its enzymatic activity was enhanced by adding EDTA to bFF or bS before zymographic analyses. Experiments using specific inhibitors of MMPs indicated that GA110 and 62 kDa proteins were indeed gelatinases. Immunoblotting experiments using an antibody against human MMP-2 showed that both GA110 and 62 kDa were an MMP-2 isoform and active MMP-2, respectively. The results suggest that the interaction between bFF and bOF can occur at the time of fertilization.