• Korean Journal of Cognitive Science
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• v.8 no.4
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• pp.11-18
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• 1997

야간 시각은 민감도를 극대화하고 주간 시각은 세감도를 극대화한다. 민감도와 세감도는 시각 기능의 두 목표이지만 상쇄적인 작용때문에 균형적인 선택이 요구된다. 민감도와 세감도를 결정하는 중요한 요인으로는 광학적인 요인과 신경학적인 요인이 있다. 망막의 지역적 분화는 바로 이러한 민감도-세감도 문제에서 기인하는데 망막의 2차원적인 제약이 시각신경계의 병행적인 경로와 이에 기초한 적응적 진화를 통해서 어느 정도 해소되는 듯이 보인다. 이 글은 야행-주행 습성을 동시에 갖추어 민감도와 세감도의 균형 문제가 각별히 부각되는 고양이의 초기 시각신경계에서 민감도와 세감도의 균형을 최적화하는 신경 기전을 소개한 것이다.

• Journal of Plant Biotechnology
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• v.44 no.2
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• pp.171-177
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• 2017

A callus-mediated regeneration protocol for sea-milkwort, an endangered coastal plant species in South Korea, is reported here. The explants of in vitro-plantlets generated from a node culture revealed distinguishable responses in callus induction depending on genotype, explant source, light condition, and 2,4-D concentration. Especially, continuous darkness exclusively facilitated callus induction from explants prior to other treatments. The calli initiated on the media with 2,4-D ranging from 0.1 mg/L to 3.0 mg/L in the dark vigorously proliferated when subcultured on the same media in continuous darkness. Given 1.0 mg/L zeatin in addition to darkness to the calli of the 'Pistachio' genotype, normal adventitious shoots were only regenerated from nodular structures that formed earlier from the calli at the frequency of 24.4 percent. Regenerated shoots easily grew into plantlets with roots and green color on a phytohormone-free MS medium under lighted condition, that were used for node culture as plant materials. Node culture effectively multiplied plantlets in accordance with protocol by Bae et al. (2016). Acclimatized plantlet clusters developed mature plant clusters under inland environment, followed by flowering the following April. Results were merged with node culture protocol suggested by Bae et al. (2016), which, as an in vitro propagation system for sea-milkwort, may contribute to natural habitat restoration.

• Korean Journal of Microbiology
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• v.49 no.1
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• pp.8-16
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• 2013

A GAL4 type transcription factor gene (formally annotated as AN3912) locating downstream of sndA (AN3911) was characterized. The putative transcription factor carries both Zn(II)2Cys6 binuclear cluster DNA-binding domain and transcription activator domain. The gene named gtfA (gal4 type transcription factor) had an open reading frame which consisted of 762 amino acids and was disrupted by three introns. The deletion mutant produced reduced amount of conidia but increased amount of fruiting bodies, suggesting that the GtfA make function in decision of asexual preferential to sexual development. The forced over expression of gtfA caused the retardation of fruiting body formation on high glucose concentration. The transcript level of gtfA was kept constant through the life cycle except late vegetative stage and early sexual development stage during which slight increase was found. The expression of gtfA was not significantly affected by sexual or asexual development regulators, such as VeA, NsdD or FluG, FadA, and SfaD. The GtfA repressed the nsdC transcription, which suggested that GftA control sexual development negatively via negative regulation of nsdC expression.

• Korean Journal of Microbiology
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• v.42 no.4
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• pp.246-251
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• 2006

A lot of mutants which cannot initiate sexual development were screened and several loci including nsdA, nsdB, nsdC, and nsdD were identified in homothallic ascomycetes Aspergillus nidulans. The NSD206, which has nsdC6 allele, showed typical phenotype of NSD (Never in sexual development) mutants. The nsdC gene was cloned by transforming NSDP697 ($nsdC^-$, $pryG^-$) with AMA1-NotI genomic library. The transforming library DNA recovered from several transformants showing wild phenotype carried about 10 kb genomic DNA insert. The DNA sequence of nsdC was analysed using GPS (Genome priming system). The nsdC gene has an open reading frame (ORF) of 1,929 bp encoding a putative polypeptide of 643 amino acids. The NsdC carries $C_2H_2C_2H_2C_2HC$ type zinc finger DNA binding domains in the middle of the polypeptide. A coiled-coil domain at its C terminus were also found. In nsdC6 allele, a single T insertion was occurred between 407-408 bp leading to the frameshift mutation and early termination of translation producing the truncated protein which has only 139 amino acids.

• Development and Reproduction
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• v.10 no.3
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• pp.169-175
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• 2006

Ginseng is the best known and most popular herbal medicine used worldwide. In spite of reported beneficial effects of ginseng on the CNS, there is few scientific evidences established at the cellular level. Among more than 30 ginsenosides, Rb1 and Rg1, the active ingredients of ginseng, are regarded as the main compounds responsible for many pharmaceutical actions of ginseng. Daily treatment with Rb1 or Rg1 for 3 d significantly decreased the number of bromodeoxyuridine(BrdU)(+) cells in primary neural progenitor cells(NPCs) isolated from hippocampi at embryonic day 16.5(E16.5). In contrast, treatment with Rb1 or Rg1 greatly increased the number of microtubule associated protein(MAP2) (+) cells. In addition, the transcription factors, Ngn1 and Hes1, proneural members of the basic helix-loop-helix(bHLH) family, significantly increased in Rb1 or Rg1 treated-NPCs. Based on these results, we suggest for the first time that ginsenosides Rb1 and Rg1 decrease proliferation but promote neuronal differentiation of hippocampal NPCs.

• Journal of the Korea Convergence Society
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• v.10 no.4
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• pp.81-89
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• 2019

This study was analyzed about the relationship between culture microenvironment and cell differentiation of HPV 16 E6/E7-transfected immortalized oral keratinocyte(IHOK). By the alteration of culture environment, IHOK-EF and IHOK-EFKGM were obtained, and the modulation of cell properties was observed by cell proliferation assay, immunofluorescence, microarray, and quantitative real-time PCR analysis. IHOK-EF losed the properties of epithelial cells and obtained the properties of mesenchymal cells, and in the result of microarray analysis, genes related to the inhibition of differentiation such as IL6, TWIST1, and ID2 were highly expressed in IHOK-EF. When the culture environment was recovered to initial environment, these changes were recovered partially, presenting the return of genes involved in the inhibition of differentiation such as IL6, and ID2, particularly. This study will contribute to understand adjustment aspect for cell surviving according to the change of culture microenvironment in the study for determining the cell characteristic, and facilitate therapeutic approach for human disease by applying surviving study according to the change of cancer microenvironment.

• The Korean Journal of Zoology
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• v.25 no.3
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• pp.107-114
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• 1982

A combination of ultraviolet irradiation and egg rotation was applied to Korean frogs to study the mechanisms of the establishment of the dorsal-ventral polarity. Rotation of the uncleaved egg was capable of preventing the characteristic syndromes associated with UV irradiation. As well, brief rotation of the egg before cleavage relocates the site of dorsal lip to a novel location in the embryo at gastrula stage. That is, the dorsal lip appeared on the opposite side to gravity at the rotation of the egg. Above results were discussed with the informations obtained from other anuran and urodele species, and were interpreted in terms of regulating mechanisms for early embryogenesis.

• Proceedings of the Korea Information Processing Society Conference
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• 2000.04a
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• pp.89-93
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• 2000

구조 적응형 자기구성 지도는 일반적으로 자기구성 지도의 구조가 초기에 결정되어 학습이 끝날 때까지 변하지 않기 때문에 발생하는 문제를 해결하기 위해 지도의 구조를 학습 중에 적절하게 변경시킨다. 이때, 변화된 구조의 가중치를 어떻게 초기화시킬 것인가 하는 것이 중요한 문제이다. 이 논문에서는 기존의 비교사 학습방법에 LVQ 알고리즘을 이용한 교사 학습방법을 결합한 구조 적응형 자기구성 지도 모델에서 유전자 알고리즘을 이용하여 분화된 노드의 가중치를 결정하는 방법을 제안한다. 이 방법은 기존의 구조 적응형 자기구성 지도 알고리즘보다 빠르게 학습되었고, 인식률 면에서도 기존의 방법보다 높은 값을 나타내었으며, 자기구성 지도의 특성인 위상 보존도 잘 이루어졌다. 오프라인 필기 숫자 데이터로 실험한 결과, 제안한 방법이 유용함을 알 수 있었다.

• Proceedings of the KIEE Conference
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• 2006.11a
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• pp.170-173
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• 2006

2006년 9월 1일에 제정된 독립사업부제는 각 단위별로 자율적인 운영권을 가지면서 비용 등에 대해서도 스스로 책임지도록 하는 제도이다. 배전계통의 사업구역 분할로 시작된 배전 사업부제는 독립 재무제표를 통해 경영실적이 드러나기 때문에 경영혁신과 원가절감 경쟁을 유도할 수 있다는 게 특징이다. 이런 체제의 변화는 기업의 규제 시스템에도 새로운 변화가 필요하게 될 것이다. 하지만 서로 다른 규모와 환경을 가진 사업부들을 하나의 기준으로 평가하는 것은 어려운 일이다. 그래서 본 논문에서는 배전 사업부제로 인해 나눠진 사업부들의 경제성과 상대적인 가치를 평가할 수 있는 방법 중의 하나로 세계적으로 널리 쓰이고 있는 Data Envelopment Analysis를 제안한다. 그 결과를 통해서 사업부에 대한 경영 평가나 각 사업부가 더 높은 경제성을 갖출 수 있는 RPI-X regulation을 수행하는데 하나의 모델로서 사용될 수 있을 것이다. RPI-X regulation에서 X값을 결정하는 것은 비용 경쟁력을 향상시키는 비율을 나타내기 때문에 적절한 X값을 찾는 것이 가장 중요하다고 하겠다. 이 때 여러 개의 입력과 여러 개의 출력을 가지는 문제에 대해서 쉽게 결과를 나타낼 수 있는 Data Envelopment Analysis를 X를 결정하는 방법으로 사용하였다. 그리고 사업부들의 노동력과 선로긍장과 용량 등의 값을 입력으로 하고 고객호수와 판매량을 결과로 하여 RPI-X regulation의 적절한 X값을 찾는 예를 통하여 이 방법이 실제적으로 어떤 효과가 있는지 확인해보았다. 본 논문에서는 분화된 사업부들에 대하여 Data Envelopment Analysis 기법을 이용하여 RPI-X regulation을 수행하였고 결과적으로 본 논문에서 제안한 방법을 통하여 분화된 배전 시스템에도 적용할 수 있는 가능성을 보였다.

• Journal of Families and Better Life
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• v.32 no.5
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• pp.41-61
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• 2014

The purpose of this study was to investigate whether differentiation of self mediates the relationship between parenting styles (i.e., care and overprotection) and the level of career decision-making among young adults. We separately measured the mother's and the father's parenting styles and five dimensions of differentiation of self that S. Je (1989) suggested. The data came from 387 young adults who were juniors and seniors at universities in Seoul and its surrounding cities. Using Baron and Kenny's (1986) steps based on regression, we found that the relationships between both caring and overprotective parenting styles and young adults' level of career decision-making were mediated by four dimensions of differentiation of self (i.e., intellectual functioning vs. emotional functioning, family projection process, emotional cutoff, and family regression) except for integration of self. The results were consistent for both the mother and the father. Bootstrapping tests showed that all of the mediation effects were statistically significant. This study contributes to the literature by showing that young adults' level of career decision-making is not simply determined by inputs such as parenting styles but is also mediated by differentiation of self. The results of this study are meaningful in that both the mother's and the father's parenting styles could make a difference in young adults' level of career decision-making through differentiation of self.