• Clinical and Experimental Pediatrics
• /
• v.52 no.1
• /
• pp.111-118
• /
• 2009

Puopose : Exposure to dietary phytoestrogens such as genistein during early childhood is a growing public health concern. We examined the effect of early exposure to genistein on sexual maturation in immature rats. Methods : Weaning (3wk-old) Sprague-Dawley female rats were assigned to three groups (n=6 for each): fed by high dose of genistein (100 mg/kg/d), low dose of genistein (10 mg/kg/d) and control group. First vaginal opening (VO) day was observed. Structural alterations in the ovary and uterus were assessed by histologically. Expression of genes of $ER{\alpha}$, $ER{\beta}$, and progesterone receptor (PR) in the ovary and uterus were investigated by RT-PCR. Results : High genistein group had earlier VO than control and low genistein group. Graafian follicles and corpora lutea were observed from the ovary of genistein-treated groups, while primary, secondary follicles and small atretic follicles were observed in the control group. Hypertrophy of luminal and glandular uterine epithelia were found in the genistein-treated groups while poor development of gland and fewer myometrial cell layers were evident in control group. In ovary, the transcriptional activities of $ER{\alpha}$ and $ER{\beta}$ were higher in high genistein group than in controls. In uterus, the transcriptional activities of $ER{\alpha}$, $ER{\beta}$ and PR were higher in low genistein group than in controls. Conclusion : Acute exposure to genistein during the prepubertal period could activate the reproductive endocrine system resulting in the early onset of puberty in female rats. Further clinical investigation on the effect of genistein on the sexual maturation in children is warranted.

• Journal of Korea Technology Innovation Society
• /
• v.17 no.3
• /
• pp.604-628
• /
• 2014

We analyse the impact of R&D cooperation on Industrial R&D programs of Government (Ministry of Trade, Industry & Energy, MOTIE), specially performance differentiating between type of R&D partners, type of R&D project leader organizations. And considering five performance measures: paper, patent, technology transfer, commercialization, new employment. Using data on a large sample of post-performance survey of MOTIE in Korea (2013), we examine the impact of R&D cooperation in 2008-2012. The method of analysis is binary logistic regression models operated by SPSS. The results of this study are follows; the performance is statistically significantly different between type of R&D partners, type of R&D project leader organizations on R&D cooperation. Specially, when a private enterprise cooperate with non-profit institutions, performance has a greater success of paper, patent, new employment. On the other hand, when a private enterprise cooperate with a private enterprise cooperate, performance decrease success of paper, technology transfer. Lastly, when non-profit institutions cooperate with a private enterprise, performance has a greater success of patent, technology transfer.

• The Journal of the Petrological Society of Korea
• /
• v.3 no.3
• /
• pp.185-195
• /
• 1994

An experimental study of iron-aluminium partitioning between synthetic garnet and synthetic epidote was carried out, as equilibrium was maintained in the exchange reaction expressed as follows : $Ca_3Fe_2Si_3O_12\+\2\Ca_2Al_2AlSi_3O_12$(0H) = $Ca_3Al_2Si_3O_12\+\Ca_2Al_2FeSi_3O_12$(0H) Temperature has a pronounced effect on the distribution of Fe and A1 between the minerals. However, the pressure effect is not so drastic as in the exchange reaction. With increasing temperature, $Fe^{+3}$ becomes redistributed from garnet into epidote, whereas A1 becomes redistributed from epidote into garnet. This is in line with the general principle of phase correspondence, as the temperature increases the more electropositive metal aluminium redistributes from epidote into garnet. The agreement between the experimental results of this study and the natural samples suggests that $K_D=X^{Ep}_{Fe}/X^{Gr}_{Fe}$ may be a useful geothermometer for metamorphic rocks containing garnet and epidote that are close to binary Fe-A1 compounds.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.10 no.11
• /
• pp.3363-3372
• /
• 2009

Continued jobless growth in economy, coupled with the current economic recession, is aggravating the situation of job market. In order to create more jobs and reduce the economic gap in a society, an independent creative firm of a sole entrepreneurs is suggested as an alternative mean. Understanding entrepreneurial motivations of a sole entrepreneur will be helpful in developing educational programs on starting an independent creative firm and in establishing a relevant government policy. This study, therefore, proposes a new model on entrepreneurial motivations in the independent creative firm and performs case study. The results of the study show that the personal environment and the personal characteristics of entrepreneurs have much effects on motivation of starting the independent creative firms. Among the personal environments, entrepreneurs' educational backgrounds, work experiences, and personal networks have great influences on entrepreneurial motivations. The processes of sustained entrepreneurship involve: (a) the determination of business ideas and goals, (b) the inception of a new business and managerial activities, (c) the entrepreneur's assessment of both intrinsic and extrinsic rewards of business performances, and (d) the adjustment of business ideas and goals in accordance with the results of the assessment. The results of the study could be applied in developing educational programs and consulting guidelines on independent creative firms and in establishing government's supportive policies on the firm.

• Korean Journal of Materials Research
• /
• v.11 no.5
• /
• pp.405-412
• /
• 2001

Corrosion tests were carried out in $360^{\circ}C$ water and $360^{\circ}C$ 70ppm LiOH solution to investigate the corrosion behavior of new zirconium alloys (Zr-0.4Nb-0.8Sn-xFeCrMn, Zr-0.2Nb-1.1Sn-xFeCrMn, Zr-1.0Nb-xFeCu). Microstructures of tested alloys were analyzed by optical microscope and TEM. The cross-sectional surface and crystalline structure of the oxide layer were analyzed by SEM and XRD. From the results of corrosion test, all the alloys showed higher corrosion rates in $360^{\circ}C$ 70ppm LiOH aqueous solution thats in $360^{\circ}C$ water. Especially, high Nb-containing alloy exhibited the acceleration of corrosion rate in LiOH solution. The low Nb- and Sn-added alloys showed better corrosion resistance than the Sn- free high Nb alloy. from the effect of final annealing on the corrosion, it was observed that the partially recrystallized alloys showed better corrosion resistance than fully recrystallized alloys. This would be related to the size and distribution of the second phase particles.

• Culinary science and hospitality research
• /
• v.21 no.5
• /
• pp.72-87
• /
• 2015

The purpose of this study is to investigate how environmental attitudes of top managers of hotel business affect on environmental commitment of hotel employees and identify of the mediator effects of line supervisor and peer group during implementing green management process using Sobel z test. Data analysis is conducted by SPSS 18.0. The findings and implications can be summarized as follows. First, environmental attitudes of top managers has significantly positive effect on environmental attitude of line supervisors and peer group. Second, environmental attitude of line supervisors and peer group, in turns, has significantly positive effect on value or normative commitment on green management of hotel employments. Third, there is positive mediating effect of environmental attitude of line supervisors and peer group between environmental attitudes of top managers and value or normative commitment of hotel employees. Hence we can conclude that implementing of green management intention of top managers to hotel employs in work place needs strong support of line supervisors and peer group.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.18 no.2
• /
• pp.85-94
• /
• 2017

This study examined the factors influencing the health status according to class and socioeconomic class recognition by the employment type. To take advantage of the 18 original sources of the Korea Labor panel materials carried out in the South Korea Labor Institute, 5,158 adults over 20 years old were included in the final analysis. The research results revealed that the incomes of regular workers and non-regular workers between the hierarchy and socioeconomic hierarchy recognition showed a statistically significant difference between the cage; it was consistent between the hierarchy in only the "heavy" category. Regular workers of society, and regardless of non-regular workers, were analyzed to be relatively low compared to the actual income. Regression analysis showed that regular jobs had higher socioeconomic hierarchy recognition. Non-regular workers had a lower income bracket and lower socioeconomic hierarchy recognition. In particular, in the case of non-regular workers, the pension was not subscribed and they had a poorer state of health. Therefore, the pension insurance payment for non-regular workers needs to compensate for the lost income during non-employment periods. In addition, the government should improve public relations through education, management fields, and cooperation with labor.

• Korean Journal of Materials Research
• /
• v.4 no.7
• /
• pp.775-782
• /
• 1994

Influence of $TiO_{2}$ addition on sintering behavior and microstructure of MgO-$ZrO_{2}$ composites was studied. $ZrO_{2}$ containing 3mol%Y203 was existed as a c-$ZrO_{2}$ phase due to the formation of solubility of MgO, $TiO_{2}$ and $ZrO_{2}$ when sintered $1400^{\circ}C$ for 2h. All the compositions employed exhibited a similar shrinkage behavior with an end-point shrinkage between 8.58 and 11.00%. The additlon of $TiO_{2}$ promoted densification and the bulk density of specimen containing 1.67wt% $TiO_{2}$ was 3.75g/$\textrm{cm}^3$(98% TD) when $1600^{\circ}C$ for 2h. The amount of solubilities of MgO and TiOz in $ZrO_{2}$ were 5.ti7wt% and 2.62wt%,respectively. They were partially segregated near $ZrO_{2}$ grain boundary in the form of Ti-compounds during cooling. This segregation resulted in the formation microcracks which decreased the bending strength.

• 한국노년학
• /
• v.36 no.3
• /
• pp.581-594
• /
• 2016

This study aims to observe the effect of age friendliness of cities on life satisfaction and to suggest ways to improve quality of life of older people. The secondary data sets were used in this study, which were '2014 Survey of Living Conditions and Welfare Needs of Korean Older People.' It's a nationwide data collected by the Korean Institute of Health and Social Affairs. A multilevel analysis model was used to analyze the data because the level of age friendliness has a hierarchical data structure. Results showed as follows: First, life satisfaction of older adults is affected by the level of age-friendliness of cities in which they live. Second, on the personal level, older people showed low life satisfaction when they are more older and have more chronic diseases and more depressed. On the contrary, life satisfaction of older adults increased when they have higher education and income. Third, on the city level, older people showed higher life satisfaction when they live in high employment rate area and participation rate of lifelong education. Cautions should be placed when interpret the result because the variables that represent the characteristics of age friendless of cities were constituted arbitrary. Based on the results, suggestions for improving the city environment age-friendly and implications for social welfare practice were provided.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.20 no.9
• /
• pp.495-503
• /
• 2019

The purpose of this study was to investigate the general characteristics, work overload, work life balance, job engagement of working adolescents and the factors affecting job engagement. We examined 1,772 working adolescents under the age of 24 years in response to the fifth Korean Working Conditions Survey. Technical statistics, t-test, ANOVA, and regression analysis were used. The study results showed that men had high-level job engagement when they were professional, self-employed, 41-52 hours per week, and never experienced employment discrimination. For women, job engagement was high if they were under 19 years of age, college graduates, professions, temporary work, 41-52 hours a week, and had never experienced gender discrimination, and employment discrimination. In addition, the job engagement of both men and women was higher when work overload was less and work life balance was good. This study is meaningful in that it examined the job engagement of working youth by using the Korean Working Conditions Survey representative of Korean workers. However, it has limitations in that it does not take into account specific circumstances such as academic status or military service. Based on the study results, it can be used as basic data for developing educational programs to manage job engagement and understanding of working adolescents.