• Journal of Veterinary Clinics
• /
• v.9 no.1
• /
• pp.323-332
• /
• 1992

The present study was carried out to examine the effect of oviduct epithelium and its conditioned medium on e development of early bovine embryos in vitro. Oocytes obtained from ovarian follicles of slaughtered cows were cultured in TCM199 with 10% fetal calf serum for 22-24hrs and then fertillzed in vitro using frozen-thawed semen treated with BO-caffein, BO-BSA(20mM heparin added). Oviduct epithelium was collected in each stage of the estrus cycle and conditioned medium was the medium in which oviduct epithelium in early luteal stage was cultured. In vitro fertilized bovine embryos of 1～2 cell were co-cultured with oviduct epithelium from different estrus cycles, cultured in conditioned medium, and cultured in rabbit oviduct. The cleavage rates of in vitro fertilized early bovine embryos co-cultured with oviduct epithelial cell from early luteal, luteal and follicular phase of estrus cycle(67.2～70.8%) and cultured in conditioned medium(56.7%) were significantly(p<0.05) higher than that of the control(44.2%) The rate of development to morula or blastocyst stage in oviduct epithelial cell co-culture(15.3～32.5%) from three phase of estrus cycles and conditioned medium(14.5%) were significantly(p<0.05) higher than that of the control(5.2%). The oviduct epithelial cell from early luteal phase gave a significantly( p<0.05) higher rate of development to morula or blastocyst stage than both luteal and follicular phase. The results of in vivo culture in rabbit oviduct of early bovine embryos were 52.1% for the cleavage rate and 26.7% for the rate of development to morula or blastocyst stage.

• Archives of Pharmacal Research
• /
• v.28 no.9
• /
• pp.1057-1064
• /
• 2005

Apoptosis may occur in early embryos where the execution of essential developmental events has failed, and gangliosides, sialic acid-conjugated glycosphingolipids, are proposed to regulate cell differentiation and growth. To evaluate the regulatory roles of ganglioside GM3 in early embryonic development, this study examined its expressional patterns in apoptotic cells during early embryonic development in mice. Pre-implanted embryos were obtained by in vitro fertilization, which were treated at the 4-cell stage with three the apoptosis inducers, actinomycin D, camptothecin and cycloheximide, for 15 h. All three inducers significantly increased the percentage of apoptotic cells, as measured using a TUNEL method, but remarkably reduced the total cell numbers. The numbers of morula and blastocyst stages were significantly decreased by treatment of the embryos with the three apoptosis inducers compared with the control, with a similar result also observed in the number of blastomeres. Staining of early embryos with Hoechst 33342 revealed a significant percentage of apoptotic nuclei. Prominent immunofluo­rescence microscopy revealed a significant difference in the ganglioside GM3 expression in apoptotic embryos compared with the control, and RT-PCR also demonstrated a dramatic increase in ganglioside GM3 synthase mRNA in the apoptotic embryos. These results suggest that ganglioside GM3 may be pathophysiologically implicated in the regulation of early embryonic development through an apoptotic mechanism.

• Journal of Embryo Transfer
• /
• v.9 no.2
• /
• pp.181-188
• /
• 1994

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
• /
• v.8 no.3
• /
• pp.407-418
• /
• 2018

Science and technology have led the development of mankind, but have created problems such as natural depletion, climate change, economic inequality and poverty. The purpose of this study is to explore the meaning of early childhood science for sustainable development to solve these problems and to contribute to the harmony of nature and human beings. In order to accomplish this research objectives, 18 experts and 15 teachers were interviewed on the meaning of sustainable development and the directions of early childhood science education for sustainable development. Early childhood science education for sustainable development was categorized as follows. 'Mutual respect between child-teacher-organism', 'developing individual inquiry-based on community consciousness', 'looking at the world with child's eyes', 'deepening and expanding on topics of interest', 'continuous inquiry and commitment', 'conversation and sharing-centered exploration'. By these results, it was concluded that early childhood science education for sustainable development should start from the perspective of children, and was a meaningful process in which children constantly learn about the nature surrounding themselves based on mutual respect.

• Asian-Australasian Journal of Animal Sciences
• /
• v.19 no.4
• /
• pp.495-499
• /
• 2006

In our previous studies, we demonstrated that Vascular Endothelial Growth Factor (VEGF) enhances bovine oocyte maturation and early embryonic development in serum supplemented media. In this experiment, to determine the synergistic effect of VEGF with serum components on early embryonic development in vitro in cattle, 1 mg/ml polyvinyl-alcohol (PVA) was replaced with foetal bovine serum (FBS) in maturation and culture media. Bovine oocytes were matured in Synthetic Oviduct Fluid (SOF) supplemented with PVA, PVA+5 ng/ml of VEGF, FBS, or FBS+VEGF. Fertilized oocytes were cultured in the same conditions for 8 days. The development of embryos was examined at 48 h post- insemination and on days 6, 7 and 8. The results were analyzed using repeated measures two- factor ANOVA, in which the effects of VEGF and serum were assigned as two factors. The development rate to 4- to 8-cell embryos at 48 h was significantly higher in the PVA+VEGF group than in the PVA group (44.7% and 31.5%, respectively). However, the highest development rate to 4- to 8-cell embryos was obtained from the FBS+VEGF group (58.8%). On day 8, the blastocyst rates were higher in the PVA+VEGF (22.8%), FBS (32.1%, p<0.05) and FBS+VEGF (42.1%, p<0.05) groups than in the PVA group (17.1%). Two- factor ANOVA of the development rates indicates that VEGF had a significant effect, but had no synergistic effect with serum components on early embryonic development. The results of the present study demonstrate that VEGF improves the in vitro developmental competence of bovine oocytes and/or embryos independent of the effect of serum components.

• The Korean Journal of Community Living Science
• /
• v.20 no.4
• /
• pp.523-537
• /
• 2009

This research aimed to understand the current status of early childhood education and to develop a future direction of early childhood English education. One group interview and three private interviews were conducted with 10 early education teachers to obtain in-depth understanding of the problems inherent in English education. The findings show that there is an internal conflict in the teachers regarding the value of English education in early childhood. In addition, there are external conflicts with the children the parents, the English teacher, the program director, and the government in English education. It is concluded that the early childhood educators felt an internal conflict regarding the current, inappropriate execution of early English education which is lacking a suitable educational plan including goals and practices. Furthermore, the teacher's preference for English also contributed to the internal conflict regarding the belief in early childhood English education. Secondly, the external conflicts included: English teachers with inadequate understanding of comprehensive early childhood development, parents who show excessive interest in early childhood English education without regard to childhood development, the reality that early childhood English education is mostly influenced by the attitudes of the program director without regard for the conflicts experienced by the early childhood teacher, and the politics of the government continuing to ignore the reality that early childhood English education ontinues in practice without being included in the national curriculum.

• Proceedings of the Korea Concrete Institute Conference
• /
• 1999.10a
• /
• pp.219-222
• /
• 1999

Concrete is to be important quality in placement point and exact test method needed about early judgement method concrete on placement point. But early judgement method of concrete proposed various kind of method because the problems of accuracy and the time required of test exists, it is used within the limits. This study is to propose of early strength judgement by using microwave for accurate estimating early strength of concrete and to develop test machine. Through out this study we find that belows. 1) Strength development of concrete specimen according to the time heated by microwave showed the height strength development in 9 minutes regardless of slump and w/c. 2) As cooling time is long, strength of concrete specimen according to the time heated by microwave showed high strength development and this tendency is like regardless of heating time, w/c and slump. 3) As w/c is high, accelerating strength development according to w/c showed lower strength development and this tendency is like regardless of slump, heating time and cooling time. 4) As slump is big, compressive strength of specimen in standard curing showed lower value and as w/c is big, strength development showed lower

• BMB Reports
• /
• v.50 no.7
• /
• pp.343-344
• /
• 2017

Plants are able to recognize even small changes in surrounding temperatures to optimize their growth and development. At warm temperatures, plants exhibit diverse architectural adjustments, including hypocotyl and petiole elongation, leaf hyponasty, and reduced stomatal density. However, it was previously unknown how such warm temperatures affected the early stages of seedling development. In our recent study, we demonstrated that the RNA-binding protein, FCA, is critical for sustaining chlorophyll biosynthesis during early seedling development, which is a prerequisite for autotrophic transition at warm temperatures. FCA plays a dual role in this thermal response. It inhibits the rapid degradation of protochlorophyllide oxidoreductases (PORs) that mediate chlorophyll biosynthesis. In addition, it induces the expression of POR genes at the chromatin level, which contributes to maintaining functional enzyme levels. Our findings provide molecular basis for the thermal adaptation of chlorophyll biosynthesis during the early stages of seedling development in nature.

• Journal of Digital Convergence
• /
• v.19 no.6
• /
• pp.281-284
• /
• 2021

The importance of early childhood education has increased and early childhood education has become an important part of the education industry. Scientific and rational early childhood education can effectively promote the development of children's intelligence and is very important for the development of physical and mental health. As a rich and diverse game, educational games have been widely used not only to improve children's sense of cooperation and thinking, but also to help children develop awareness of competition and rules. Stability and personality formation stimulate young children's brain development and expect children's intellectual improvement.

• The Journal of the Convergence on Culture Technology
• /
• v.9 no.6
• /
• pp.695-702
• /
• 2023

The purpose of this study is to develop an early childhood artificial intelligence education programs in kindergartens. In order to achieve the purpose of the study, a four-step program development procedure was taken: documentary analysis, program design and development, execution, and assessment. This study presented the purpose and goals, educational content, teaching-learning methods, and evaluation of the early childhood artificial intelligence education program in kindergarten. By implementing an artificial intelligence education in the process of developing the program, the practicality and utilization of the program were secured. This study is meaningful in that it derives practical support measures to apply and activate artificial intelligence education programs in the field of early childhood education.