• 한국임상수의학회지
• /
• 제9권1호
• /
• 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
• /
• 제28권9호
• /
• 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.

• 한국수정란이식학회지
• /
• 제9권2호
• /
• pp.181-188
• /
• 1994

• 예술인문사회 융합 멀티미디어 논문지
• /
• 제8권3호
• /
• pp.407-418
• /
• 2018

인류의 발전을 주도해 온 과학기술이 만들어낸 자연고갈과 기후변화, 이로 야기되는 경제적 불평등과 빈곤 등의 문제를 해결하고 자연과 인간의 조화를 이루기 위해서는 유아기부터 지속가능발전을 지향하는 과학교육이 필요하다. 본 연구에서는 지속가능발전지향 교육의 본질과 유아과학교육의 실천방향에 대해 고찰하여 지속가능발전지향 유아과학교육의 의미에 대해 알아보고자 한다. 이러한 목적을 위하여 관련 전문가 18명과 유아교사 15명을 대상으로 지속가능발전의 의미와 지속가능발전지향 유아과학교육의 실천방향에 대해 심층 면접을 실시하였다. 연구 결과, 지속가능발전 지향 유아과학교육은 '유아-교사-생명체간 상호존중', '개별 탐구 기반 공동체 의식 함양', '유아의 눈으로 세상 바라보기', '관심 주제에 대한 심화와 확장', '지속적 탐구와 몰입', '대화와 공유 중심 탐구'로 범주화 되었다. 결론적으로 지속가능발전 지향 유아과학교육은 유아가 관심 있는 주제로부터 출발하여 상호 존중의 탐구 경험을 통해 자신을 둘러싼 자연에 대해 지속적으로 알아가는 과정이라고 볼 수 있다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제19권4호
• /
• 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.

• 한국지역사회생활과학회지
• /
• 제20권4호
• /
• 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.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
• /
• 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
• /
• 제50권7호
• /
• 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.

• 디지털융복합연구
• /
• 제19권6호
• /
• pp.281-284
• /
• 2021

유아 교육의 중요성이 증가하고 유아 교육은 교육의 산업의 중요한 부분이 되었다. 과학적이고 합리적인 유아 교육은 어린이의 지능 발달을 효과적으로 촉진 할 수 있으며 신체 및 정신 건강의 발달에 매우 중요하다. 풍부하고 다양한 게임으로서 교육용 게임은 아이들의 협동심과 사고력을 향상 시킬 뿐만 아니라 아이들이 경쟁과 규칙에 대한 인식을 키울 수 있도록 널리 사용되었다. 어린이의 시각 신경을 자극하고 어린이의 지적 발달 및 감정과 관련이 있다. 안정성과 성격 형성은 어린아이들의 두뇌 발달을 자극하고 아이들의 지적 향상을 기대한다.

• 문화기술의 융합
• /
• 제9권6호
• /
• pp.695-702
• /
• 2023

본 연구의 목적은 단위 유치원인 연구 참여 유치원의 유아 인공지능교육 프로그램을 개발하는 것이다. 연구의 목적을 달성하기 위해 문헌 분석, 프로그램 설계 및 개발, 실행, 평가의 4단계 프로그램 개발 절차를 거쳤다. 본 연구는 단위 유치원 차원의 유아 인공지능교육 프로그램 목적과 목표, 교육내용, 교수-학습 방법, 평가를 제시하였으며, 프로그램 개발 과정에서 인공지능교육을 실행함으로서 프로그램의 현장성 및 활용성을 확보하였다. 본 연구는 유아교육 현장에서 인공지능교육 프로그램을 적용하고 활성화하기 위한 실제적 지원 방안을 도출하였다는데 의의가 있다.