• Archives of Pharmacal Research
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• v.27 no.1
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• pp.86-93
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• 2004

Nitric oxide (NO) has emerged as an important intracellular and intercellular messenger, controlling many physiological processes and participating in the fertilization process via the autocrine and paracrine mechanisms. This study investigated whether nitric oxide synthase (NOS) inhibitior (L-NAME) and L-arginine could regulate in vitro fertilization and early embryonic development in mice. Mouse epididymal spermatozoa, oocytes, and embryos were incubated in mediums of variable conditions with and without L-NAME or L-arginine (0.5, 1, 5 and 10mM). Fertilization rate and early embryonic development were significantly inhibited by treating sperms or oocytes with L-NAME (93.8% vs 66.3%,92.1% vs 60.3%), but not with L-arginine. In contrast, fertilization rate and early embryonic development were conspicuously reduced when L-NAME or L-arginine was added to the culture media for embryos. Early embryonic development was inhibited by microinjection of L-NAME into the fertilized embryosin a dose-dependent manner, but only by high concentrations of L-arginine. These results suggest that a moderate amount of NO production is essential for fertilization and early embryo development in mice.

• Korean Journal of Child Studies
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• v.21 no.3
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• pp.41-51
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• 2000

This study discusses the interpretation and application of a post modern perspective to child development knowledge and early childhood teacher education. The survey of literature focused on the post modern approach to child development knowledge and early childhood teacher education, research in the reassessment of child development knowledge as it is challenged by the post modern perspective, and deconstruction of both child development knowledge and early childhood teacher education. It was concluded that child development knowledge is necessary but insufficient to early childhood teacher education. In the post modern perspective, the movement toward fostering "reflective practitioners" and basic knowledge base is more significant. Therefore, the responsibility of academics is to walk the fine line between presenting a formal knowledge base so that students gain assumption to guide their thinking and practice, critiquing both theory and derived practices.

• Clinical and Experimental Reproductive Medicine
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• v.41 no.2
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• pp.47-61
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• 2014

Stored maternal factors in oocytes regulate oocyte differentiation into embryos during early embryonic development. Before zygotic gene activation (ZGA), these early embryos are mainly dependent on maternal factors for survival, such as macromolecules and subcellular organelles in oocytes. The genes encoding these essential maternal products are referred to as maternal effect genes (MEGs). MEGs accumulate maternal factors during oogenesis and enable ZGA, progression of early embryo development, and the initial establishment of embryonic cell lineages. Disruption of MEGs results in defective embryogenesis. Despite their important functions, only a few mammalian MEGs have been identified. In this review we summarize the roles of known MEGs in mouse fertility, with a particular emphasis on oocytes and early embryonic development. An increased knowledge of the working mechanism of MEGs could ultimately provide a means to regulate oocyte maturation and subsequent early embryonic development.

• Korean Journal of Human Ecology
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• v.13 no.4
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• pp.497-506
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• 2004

This study examines the influence of early English education on children's bilingual language development to see whether the early exposure to English education affects children's competencies of both English and Korean. Based on this purpose, it attempts to examine whether it supports additive or subtractive bilingualism. The competencies of both English and Korean of the children with early English education were, therefore, compared with those of the children without it, and the relation between the two competencies was also studied. For this research, two different groups of children - one with 48 children who attend English kindergarten and the other with 60 children who attend only Korean kindergarten - took PPVT-R in Korean and in English each. The result shows that children with early English education have more English competency than those without it. No significant differences, however, are found in Korean competency between the two groups. The relation between the two competencies proves positive in children with early English education. It can thus be concluded that the effect of early English education is partially positive on children's language development, which may support the additive bilingualism that children's second language can improve without losing their native language competency. In addition, this result will be able to provide for us the direction and the guideline to the policy of foreign language education and early education.

• English Language & Literature Teaching
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• v.17 no.2
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• pp.79-91
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• 2011

The purpose of this paper was to take an in-depth look at early American English around the $17^{th}$ and $18^{th}$ century when immigrants from different European countries started to move into the New World. The paper attempted to describe early American English in relation to the process of immigration and settlement from a historical perspective. With a focus on major features of early American English such as uniformity, archaism and richness of lexicon, the paper tried to answer the questions such as how settlement influenced the formation and distribution of regional dialects across the continent, why immigrants tended to show a preference for a uniform way of speaking rather than choosing a variety of regional dialects for communication, and what role foreign languages played in the development of early American English. The overall findings based on the answers to these questions showed how American English went through a variety of processes and changes at the early stages of its development to become a national language later. The paper concluded with some remarks about the implications of the findings for EFL learning and the direction of future research on early American English.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.11a
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• pp.80-81
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• 2013

There is the increasing number of constructing soil or structure on the soft ground during public works. Usually cement or slag cement has been the traditional material for surface soil stabilization method. Recently, early strength development properties of hardening agent is required for driving abilities of execution equipment and shortening of the construction time. Therefore, the purpose of this study is to develop the early compressive strength hardening agent for surface soil stabilization. The study was confirmed performance and availability of hardening agent using early strength type cement and industrial by-product minerals through early strength development properties in accordance with water cement ratio, content of hardening agent for soft soil.

• Korean Journal of Childcare and Education
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• v.12 no.2
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• pp.113-125
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• 2016

This study examined the effects of constructivist educational beliefs and self-regulated learning skills of children on teacher professional development. The study was conducted by sampling 273 teachers. Three kinds of variables, which included constructivist educational beliefs, self-regulated learning ability, and professional development level were measured and analyzed for this study. The results were as follows. First, early childhood teachers beliefs of constructivist education, self-regulated learning ability and professional development were found to be higher than average. Second, the professional development of early childhood teachers is shown to be correlated with constructivist educational beliefs and self-regulated learning ability. When constructivist educational beliefs and self-regulated learning ability scores increases, the professional development score is high. Third, metacognitive strategies, cognitive strategies and constructivist educational beliefs are factors that predict the professional development of early childhood teachers. According to results of this study, it suggests that constructivist educational beliefs and self-regulated learning ability are important factors to be addressed.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.269-272
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• 2003

This study is intended to investigate the properties of concrete using AE Water Reducing Agent of Early-Strength Type. According to the results, as for the replacing method of mineral admixture, setting time is shortened faster in order of replacement for fine aggregate, combination and replacement for cement, and when AE Water Reducing Agent of Early-Strength Type is used, it is shortened by about 4 hours, compared with normal AE Water Reducing Agent Compressive strength is lower in the case of replacement for fine aggregate, but higher in the other case than that of plain concrete. And When AE Water Reducing Agent of Early-Strength Type is used, early compressive strength is very high in comparison to normal AE Water Reducing Agent. Early strength development is very favorable by the use of AE Water Reducing Agent of Early-Strength Type regardless of the replacing method of mineral admixture at $20^{\circ}C$, but at $l0^{\circ}C$, it is effective for Early strength development that W/B is lowered to below 45%, BS of 20% is replaced for fine aggregate, and AE Water Reducing Agent of Early-Strength Type is used.

• Journal of Environmental Health Sciences
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• v.35 no.6
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• pp.486-490
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• 2009

In January 2009, the water quality of offshore around the Incheon coast was evaluated by bioassay using early development systems of a sea urchin species, Hemicentrotus pulcherrimus. The results of performing biological evaluations on seawater samples from total of thirteen sites, showed that the formation rates of normal pluteus larva varied from 18% to 71%. In site 5 the seawater sample led to an averaage formation rate of normal larva of 18%, the highest abnormal formation rate hindering the early embryo development of the experimental animal, while that of site 3 averaged 71%, the highest formation rate of normal larva. Seawater samples from site 1, 2, 4, 7, 9, 10, 11 and 12, resulted in average formation rates of normal larva from 33% to 56%, which indicates the developmental damage of early embryos is not severe. Seawater samples from site 5, 6, 8 and 13, resulted in average formation rates of normal larva from 18% to 21% which there was strong damage to the development of early embryos.

• Korean Journal of Childcare and Education
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• v.7 no.4
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• pp.223-252
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• 2011

The purpose of this study was to examine the effect of a professional development program developed to provide an opportunity for early childhood teachers to build a firm educational belief as teachers, to have an insight into their own abilities, to keeping on reflecting on themselves and to make a prolonged effort for self-development in pursuit of an ideal life as early childhood teachers by making portfolio. And it's additionally meant to give some suggestions on the efficient implementation of the program in the future. The subjects in this study were 26 early childhood education majors. The program was provided during an eight-week period of time, and both of the collected quantitative and qualitative data showed that the program produced positive effects. The findings of the study indicate that the professional development program for preservice early childhood teachers that used career portfolio could be one of good ways to facilitate the professional development of preservice early childhood teachers and to overcome a lot of problems with education of early childhood teachers, which is lately one of primary social issues.