• Animal cells and systems
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• 제12권1호
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• pp.23-33
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• 2008

The Zic family is a group of genes encoding zinc finger proteins that are highly expressed in the mammalian cerebellum. Zic genes are the vertebrate homologue of Drosophila pair-rule gene, odd-paired(opa), which plays important roles in the parasegmental subdivision as well as in the visceral mesoderm development of Drosophila embryos. Recent studies on human, mouse, frog, fish and ascidian Zic homologues support that Zic genes are involved in a variety of developmental processes, including neurogenesis, myogenesis, skeletal patterning, and left-right axis establishment. In an effort to explore possible functions of Zic proteins during vertebrate embryogenesis, we initially examined more detailed expression pattern of zebrafish homologue of zic3(zic3z). zic3z transcripts are detected in the neuroectoderm, neural plate, dorsal neural tube, and brain regions including eye field during early embryonic development. Marker DNA studies found that zic3z transcription is modulated by BMP, Wnt, and Nodal signals particularly in the dorsal and vegetal neuroectoderm at gastrula. Interfering with zic3z translation with zic3z-specific morpholino causes abnormal brain formation and expansion of the optic stalk cells. Retinal ganglion cells(RGCs) undergo abnormal neuronal differentiation. These findings suggest that zic3z defines the dorsal and vegetal neuroectoderm to specify brain formation and retinal neurogenesis during early embryonic development.

• Molecules and Cells
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• 제41권12호
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• pp.1061-1071
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• 2018

From Xenopus embryo studies, the BMP4/Smad1-targeted gene circuit is a key signaling pathway for specifying the cell fate between the ectoderm and neuro-ectoderm as well as the ventral and dorsal mesoderm. In this context, several BMP4/Smad1 target transcriptional factors have been identified as repressors of the neuro-ectoderm. However, none of these direct target transcription factors in this pathway, including GATA1b, Msx1 and Ventx1.1 have yet been proven as direct repressors of early neuro-ectodermal gene expression. In order to demonstrate that Ventx1.1 is a direct repressor of neuro-ectoderm genes, a genome-wide Xenopus ChIP-Seq of Ventx1.1 was performed. In this study, we demonstrated that Ventx1.1 bound to the Ventx1.1 response cis-acting element 1 and 2 (VRE1 and VRE2) on the promoter for zic3, which is a key early neuro-ectoderm gene, and this Ventx1.1 binding led to repression of zic3 transcription. Site-directed mutagenesis of VRE1 and VRE2 within zic3 promoter completely abolished the repression caused by Ventx1.1. In addition, we found both the positive and negative regulation of zic3 promoter activity by FoxD5b and Xcad2, respectively, and that these occur through the VREs and via modulation of Ventx1.1 levels. Taken together, the results demonstrate that the BMP4/Smad1 target gene, Ventx1.1, is a direct repressor of neuro-ectodermal gene zic3 during early Xenopus embryogenesis.

• 한국정보통신학회논문지
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• 제17권3호
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• pp.730-739
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• 2013

국내 에너지의 30%이상이 조명부문에서 소비되고 있어서 그 소비량과 $CO_2$ 배출량은 점차적으로 늘어날 수밖에 없다. 이와 같은 상황에서 스마트그리드 기반의 전등 제어시스템 구축에는 중요한 의미가 있다. 결과적으로 오늘날 산업현장에서 사용되는 전력선망 통신모뎀과 응용 단말기들을 활용, 본 논문은 PC기반의 전력선망 통신 제어시스템을 구현해봄과 동시에 다양한 통신 테스트 장치 및 도구로 활용하는데 유용할 것이다. 실험을 위해서 사용되는 모뎀은 ZIC 프로토콜 기반의 플래넷 제품을 활용하고 응용프로그램은 랩뷰(LabView)를 사용한다. 그 결과는 주로 저속 전력선 통신에 의한 장치 제어에 초점이 맞추어져 있으며, 전력선 통신 실험을 위한 전력선 통신 테스트 장치로 각종 실험을 수행할 수 있다.

• Molecules and Cells
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• 제44권10호
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• pp.723-735
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• 2021

Spemann organizer is a center of dorsal mesoderm and itself retains the mesoderm character, but it has a stimulatory role for neighboring ectoderm cells in becoming neuroectoderm in gastrula embryos. Goosecoid (Gsc) overexpression in ventral region promotes secondary axis formation including neural tissues, but the role of gsc in neural specification could be indirect. We examined the neural inhibitory and stimulatory roles of gsc in the same cell and neighboring cells contexts. In the animal cap explant system, Gsc overexpression inhibited expression of neural specific genes including foxd4l1.1, zic3, ncam, and neurod. Genome-wide chromatin immunoprecipitation sequencing (ChIP-seq) and promoter analysis of early neural genes of foxd4l1.1 and zic3 were performed to show that the neural inhibitory mode of gsc was direct. Site-directed mutagenesis and serially deleted construct studies of foxd4l1.1 promoter revealed that Gsc directly binds within the foxd4l1.1 promoter to repress its expression. Conjugation assay of animal cap explants was also performed to demonstrate an indirect neural stimulatory role for gsc. The genes for secretory molecules, Chordin and Noggin, were up-regulated in gsc injected cells with the neural fate only achieved in gsc uninjected neighboring cells. These experiments suggested that gsc regulates neuroectoderm formation negatively when expressed in the same cell and positively in neighboring cells via soluble factors. One is a direct suppressive circuit of neural genes in gsc expressing mesoderm cells and the other is an indirect stimulatory circuit for neurogenesis in neighboring ectoderm cells via secreted BMP antagonizers.

• 한국정밀공학회지
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• 제16권5호통권98호
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• pp.160-168
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• 1999

This paper describes one method of reverse engineering that machines a free form shape without descriptive model. A portable five-axes 3D CMM was used to digitize point data from physical model. After approximation by rational B-spline curve from digitized point data of a geometric shape, a surface was constructed by the skinning method of the cross-sectional design technique. Since a surface patch was segmented by fifteen part, surface merging was also implemented to assure the surface boundary continuity. Finally, composite surface was transferred to commercial CAD/CAM system through IFES translation in order to machine the modeled geometric shape.

• 한국식품영양과학회지
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• 제30권3호
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• pp.540-546
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• 2001

The purpose of this study was to investigate the relationship among nutritional status of copper and zinc, serum leptin, and lipids of 99 middle school girls residing in kyunggi-do, Korea. Subjects were divided assigned to one of two groups such as normal (BMI<85 percentile, n=58) and obese (85$\leq$BMI, n=41) groups. Subjects were evaluated based on anthropometric measurements, 24-hr dietary recalls and blood analysis. The mean age was 13.93 years. The mean weight (p<0.001), BMI (p<0.001), body fat (p<0.001) of obese were significantly higher then those of normal group. The mean daily energy intake was 94.2% of RDA for Korean. The ratio of energy coming from carbohydrate, fat and protein was 63:24:13. The mean daily intakes of Cu and Zn were 1.4 mg and 7.4 mg (73.7% of RDA), and there were no significant difference between two groups. The mean serum levels of leptin (p<0.001), LDL-cholesterol (p<0.05), triglyceride (p<0.01), TPH (total cholesterol/HDL; p<0.001), LPH (LDL/HDL; p<0.001) and AI (atherogenic index; p<0.001) of obese were significantly higher than those of normal group. The mean serum Cu level of obese was significantly higher than normal group but, the mean serum Zn level of obese was significantly lower than normal group. Serum Cu showed a significantly positive correlations with body weight (p<0.001), BMI (p<0.001), body fat (p<0.001), serum leptin, and LPH. However, serum Zn showed a significantly negative correlations with body weight (p<0.001), BMI (p<0.001), serum leptin (p<0.001), TPH (p<0.05), and AI (Atherogenic index; p<0.05). To summarize the results, the Zn intakes of middle school girls did not reach to RDA for Koreans. Also, increase of BMI may lead to decrease of serum zinc level and increase of serum copper level, and this change of serum zinc related to the change of serum leptin and serum lipids level in middle school girls during rapid growth.