• Title/Summary/Keyword: Developmental study

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Studies on the Survival Rate of Bisected Porcine Embryos and Immature Oocytes (돼지 분할 수정란 및 미성숙란의 생존율에 관한 연구)

  • 김상근;이명헌;서길웅
    • Korean Journal of Animal Reproduction
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    • v.19 no.2
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    • pp.129-134
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    • 1995
  • This study was carried out to investigate on the survival rate and in vitro developmental rate of bisected porcine embryos and immature oocytes by manipulator and micropipette. Bisected embryos and immature oocytes cultured for 1∼5 days in TCM 199 medium with 20% FCS. Survival rate was defined as development rate on in vitro culture or FDA-test. The results are summarized as follows ; 1. The survival rate of bisected porcine embryos and oocytes were 26.1%, 22.7%, respectively. The survival rate of bisected embryos and oocytes was significantly lower than that of non-bisection embryos(62.5%). 2. The survival rate of bisected porcine embryos in cultured for 12, 24, 48, 72 hrs with 20% FCS+TCM-199 medium were 26.9%, 19.2%, 19.2% and 11.5%, respectively. 3. The in-vitro developmental rate with and without zona pellucida of bisected porcine embryos by micromanipulator were 30.8%, 25.0%, respectively.

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Effects of Preschoolers' Visual Perception on Reading Words in Hangul : Application of the Test of Visual Perception for Reading (유아의 시지각 발달과 읽기 : 수.방향.형태항상성 지각이 한글 단어 읽기에 미치는 영향)

  • Choi, Na-Ya
    • Korean Journal of Child Studies
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    • v.30 no.2
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    • pp.161-177
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    • 2009
  • In this study of the relationship between preschoolers' visual perception and reading Hangul words, the 287 participants showed significant developmental change in visual perception between three to five years of age. The researcher developed the computer-based screening Test of Visual Perception for Reading (TVPR). Factor analysis confirmed three factors of TVPR : perception of number, direction, and form constancy. These factors correlated highly with four factors of motor-reduced visual perception of the Korean Developmental Test of Visual Perception (Moon et al. 2003). All factors of TVPR explained reading real words and pseudo words; direction and form constancy perception predicted reading low frequency letters. These findings confirm that preschoolers' skills in visual perception contribute to the reading of words in Hangul.

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The Time-dependent Effects of Changes in Private Education on the Developmental Trajectories of Academic Achievement Among Early Adolescents (아동의 학업성취 발달궤적에 대한 사교육의 시간 의존적 효과)

  • Lee, Ju-Lie
    • Korean Journal of Child Studies
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    • v.31 no.6
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    • pp.1-13
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    • 2010
  • This study examined the time-dependent effects of changes in private education on the trajectories of academic achievement among early adolescents. Five-wave data was employed from the KYPS; the participants being 2844 (1524 boys, 1320 girls). All were 4th graders in 2004 and became 8th graders in 2008. Latent growth curve model indicated that academic achievement significantly decreased over the five time points, but there were significant individual differences as well. Participants who reported higher initial levels of academic achievement tended to decrease in academic achievement more slowly over time compared to participants who reported lower levels of initial academic achievement. The effects of private education on academic achievement were at their most powerful when participants were in the 4th grade. Private educational experiences among 6th graders had relatively less influence upon the academic achievement of 7th graders.

Measurement of the Metabolism of Energy Substrates in Single IVF-derived Bovine Embryos (소 체외수정란에 있어서 Non-invasive 방법에 의한 기질 대사량의 측정)

  • ;;S. Sugawara
    • Korean Journal of Animal Reproduction
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    • v.19 no.3
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    • pp.161-169
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    • 1995
  • To investigate the metabolism of various substrates in preimplantation bovine embryos, uptake of glucose and pyruvate, and lactate production were measured in single IVF-derived bovine embryos by a non-invasive method. When the embryos were incubated for 5 h in culture medium supplemented with 1 mM glucose and 0.4mM pyruvate as substrates at each developmental stage, glucose uptake was increased with more advanced developmental stages while pyruvate uptake was decreased. Total lactate producton of 2-cell embryos was significantly higher than that of blastocysts (p<0.05). Both of glucose uptake and lactate production in normal morulae produced in vitro was significantly high compared to the degenerated embryos(p<0.05). The results obtained in the study suggest that pyruvate as an exogenous substrate may be support in bovine embryos until 8-cell stage, whereas glucose may be effective as an energy source after morula stage. In addition, it was proven thatlactate was not effective as an energy source in preimplantation development of IVF-derived bovine embryos.

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A study on Motor Skill Relearning (운동기능 재학습에 관한 연구)

  • Shin, Hong-Cheul
    • The Journal of Korean Physical Therapy
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    • v.1 no.1
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    • pp.47-61
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    • 1989
  • This paper presents the event approach to motor skill acquisition as a theoretical treatment of the learning and relearning of motor skill. 1) The use of norm-referenced developmental assesment tools and standardized qualitative assessment tool is an important component of infant movement evaluation. 2) The kinesthetic modality relaying movement and position imformation to the central nervous system is important for the detection and corretion of movement error. 3) The event approach treats the actor and the environment as inseparable in the acquisition of skills. 4) Motoy learning focuses almost entirely on how the skill is learned, contRolled and reTained. 5) Developmental assessment have needed an assessment of motor development. 6) A significant difference was found between articulation disorders children and motor coordination problem. 7) verbal ability is not essential for the learning of motor skills. 8) The Control of motor skills is a cognitive ability.

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Studies on In Vitro Developmental Rate of Activated Bovine Oocytes by Intracytoplasmic Sperm Injection with Frozen-Thawed Epididymal Spermatozoa

  • Lee, Dongsoo;Kim, Sangkeun
    • Proceedings of the KSAR Conference
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    • 2002.06a
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    • pp.52-52
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    • 2002
  • The objective of this study was to determine the developmental competence of in vitro matured bovine oocytes after intracytoplasmic sperm injection(ICSI) with frozen-thawed epididymal spermatozoa. The ovaries were obtained from slaughtered Korean native cows. Oocytes matured in vitro for 24 hrs were fertilized by ICSI with frozen-thawed epididymal spermatozoa. After ICSI, one group of oocytes was activated with 7% ethanol for 5 min, and second group was not activated. The follicular oocytes were cultured in TCM-199 medium containing hormones and 10% FCS for 24-30 hrs in a incubator with 5% CO₂ in air at 38.5℃. (omitted)

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Analysis about Developmental Changes of Children's Metamemory (아동의 메타기억의 발달적 변화에 관한 분석)

  • Park, Young-Ah
    • Korean Journal of Human Ecology
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    • v.16 no.6
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    • pp.1141-1152
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    • 2007
  • The purpose of this study was to investigate developmental changes of metamemory. The subjects were 120 5, 7, and 9 year-old children. All children performed metamemory tests which were composed of person variable, task variables, and strategy variable. There were significant age differences in metamemory awareness. As for person variable, prediction accuracy was increased with age. As for task variables, older children recognized aims of tasks, whereas younger children perceived salient properties of tasks. Also, as for strategy variable, number and complexity of strategy for memory retrieval were increased with age.

A Case of Ring Chromosome 21 with Multiple Congenital Anomalies (다발성 선천성 기형을 가진 21번 환(Ring) 염색체 1례)

  • Lee, Jun-Hwa;Seo, Eul-Ju
    • Clinical and Experimental Pediatrics
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    • v.46 no.3
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    • pp.291-294
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    • 2003
  • Ring chromosome 21 causes a multitude of phenotypes, ranging from severe abnormalities to normal. The proposed mechanism of ring formation, breakage of both short and long arms of a chromosome with subsequent end to end fusion, remains unproven. We encountered a 4-year-old boy who presented developmental delay, microcephaly, micrognathia, hypertelorism, low-set ears, mild optic nerve hypoplasia, cleft lip and palate, scoliosis and left foot valgus, but normal brain MRI. Chromosome study from peripheral blood showed 46,XY, r(21)(p11.2q22.1) karyotype. The authors report the first case of ring chromosome 21 in Korea with a review of the literature.

A Study on the Development of Civil Aviation Industry and Civil Aviation Law of China (항공운송산업 발전에 따른 중국 민용항공법의 문제점 및 개선방향에 대한 고찰)

  • Park, Myoung-Sup;Chen, Zhen-Ghui;Yun, Jae-Ho
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.42
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    • pp.211-245
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    • 2009
  • In this paper we firstly review the developmental stages of the Chinese civil aviation industry since 1949 and the background history of the Chinese Civil Aviation Law of 1996. We secondly analyzed the main terms and conditions about the Chinese civil aviation law and pointed out several problematic issues in view of the development of the Chinese aviation industry. Current civil aviation law in China has been in effect for the last 12 years. In these periods, Chinese civil aviation industry has developed in a high speed and great changes have occurred in its market environments. Thus, some of the terms and conditions in current civil aviation law in China have become outdated and unsuitable for the current developmental stage of the Chinese civil aviation industry. Therefore, we proposed some directions of the future amending of the Chinese Civil Aviation Law.

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A Study on the New Developmental Ststegies for Promotion of Rural Economy (농촌지역 산업진흥을 위한 새로운 발전전략의 모색)

  • 이동필
    • Journal of Korean Society of Rural Planning
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    • v.1 no.1
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    • pp.111-124
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    • 1995
  • This paper discuss on the strategies for rural economic development Maul purposes of this paper are as follow: First, to review importance of economic promotion in the integrated rural developmental scheme, Second, to identify structural problems of rural economy, and Third, to suggest promotional strategies for the development of rural economy. Economic vitalization is the very important strategy to support daily life of rural population. Since rural economy heavily depends on agricultural sector which has relatively low productivities, diversification of rural economy through introduction of 2nd and 3rd industrial sector is one of the most urgent tasks in rural Korea. Integrated, localized, and planning oriented approaches with reformation of incentive system for the development of rural economy are strongly recommended as new strategies.

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