• Proceedings of the KSAR Conference
• /
• 한국동물번식학회 2003년도 학술발표대회 발표논문초록집
• /
• pp.48-48
• /
• 2003

본 실험은 spermatogonia 단계에 발현하는 유전자를 찾기 위하여 suppression subtractive hybridization를 수행하였다. 기존에 mouse에서는 spermatogonia 특이적인 유전자들이 밝혀져 있기 때문에 pig에 특이적인 유전자를 찾기 위하여 pig 250days testis와 pig 60days testis를 재료로 하여 실험하였다. SSH를 통하여 254days testis에 특이적으로 발현되는 후보유전자를 7개 찾았고 25days testis와 60days testis 의 Northern blot을 통하여 25days에 과발현하고 60days에 발현의 양이 대폭 줄어드는 spermatogonia 유전자로 생각되는 후보유전자 2개를 선택하여 pig tissue northern blot, genomic DNA southern blot, RT-PCR 그리고 In-situ hybridization을 수행하였다. Tissue northern blot과 RT-PCR을 통하여 후보자 1번은 간과 폐, 난소, 정소에서 발현하고, 후보유전자 15번은 난소와 정소에서만 특이적으로 발현함을 알았다. DNA sequence analysis와 NCBI Blast search를 통하여 후보자 1번은 다른 종에서 밝혀진 유전자였고 후보유전자 15번은 어느 종에서도 밝혀지지 않은 새로운 유전자였다. Degenerated primer를 통하여 후보자 1번의 pig full sequence를 밝히고 NCBI에 등록하였다. 그리고 In-situ hybridization을 통하여 후보유전자득이 20일째 testis의 Leydic cell에서 많이 발현되고 adult testis에서는 발현이 감소하는 결과를 얻었다. 이것으로 보아 위의 두 후보유전자는 spermatogonia에 직접 관련된 유전자이기 보다는 spermatogonia의 발달에 영향을 주는 leydic cell 특이발현을 가진 유전자로 사료되어진다.

• Reproductive and Developmental Biology
• /
• 제31권4호
• /
• pp.221-226
• /
• 2007

Embryonic stem (ES) cells are known to have an infinite proliferation and pluripotency that are associated with complex processes. The objective of this study was to examine expression of genes differentially regulated during differentiation of human ES cells by suppression subtractive hybridization (SSH). Human ES cells were induced to differentiate into neural precursor cells via embryoid body. Neural precursor cells were isolated physically based on morphological criteria. Immunocytochemical analysis showed expression of pax6 in neural precursor cells, confirming that the isolated cells were neural precursor cells. Undifferentiated human ES cells and neural precursor cells were subject to the SSH. TPX2 (Targeting Protein for Xklp2 (Xenopus centrosomal kinesin-like protein 2)) was identified, cloned and analyzed during differentiation of human ES cells into neural lineages. Expression of TPX2 was gradually down-regulated in embryoid bodies and neural precursor cells relative to undifferentiated ES cells. Targeting Protein for Xklp2 has been shown to be involved in cell division by interaction with microtubule development in cancer cells. Taken together, result of this study suggests that TPX2 may be involved in proliferation and differentiation of human ES cells.

• The Transactions of the Korean Institute of Electrical Engineers A
• /
• 제55권8호
• /
• pp.329-333
• /
• 2006

We investigated the quench characteristics of a flux-lock type superconducting fault current limiter (SFCL) depending on the number of the serial connection between the superconducting elements at the subtractive polarity winding of a transformer. The flux-lock type SFCL consists of two coils. The primary coil is wound in parallel to the secondary coil through an iron core, and the secondary coil is connected to the superconducting elements in series. The operation of the flux-lock type SFCL can be divided into the subtractive and the additive polarity windings depending on the winding directions between the primary and secondary coils. In this paper, the analyses of voltage, current, and resistance of superconducting elements in serial connection were performed to increase the power capacity of flux-lock type SFCL. The power burden was reduced through the simultaneous quenching between the superconducting elements. This enabled the flux-lock type SFCL to be easy to increase the capacity of power system.

• International Journal of Industrial Entomology and Biomaterials
• /
• 제17권2호
• /
• pp.223-228
• /
• 2008

A novel beetle antimicrobial protein from stimulated Copris tripartitus and the corresponding gene were isolated in parallel through differential display-PCR and expression in Escherichia coli. To find cDNA clones responsible for bacteria resistance, the suppression subtractive hybridization and GeneFishing differentially expressed genes system were employed in the dung beetle, Copris tripartitus immunized with lipopolysaccaride. One cDNA clone from eight subtracted clones was selected through dot blot analysis and confirmed by northern blot analysis. The 516-bp, selected cDNA clone was determined by 5' and 3' rapid amplication of cDNA ends and cloned into the GST fusion expression vector pGEX-4T-1 for expression of the protein. The expressed protein was predicted 14.7 kDa and inhibited the growth of gram-negative bacteria such as Escherichia coli and Pseudomonas aeruginosa. These results implied that the expressed protein is related to immune defense mechanism against microorganism.

• Korean Journal of Human Ecology
• /
• 제13권4호
• /
• pp.497-506
• /
• 2004

This study examines the influence of early English education on children's bilingual language development to see whether the early exposure to English education affects children's competencies of both English and Korean. Based on this purpose, it attempts to examine whether it supports additive or subtractive bilingualism. The competencies of both English and Korean of the children with early English education were, therefore, compared with those of the children without it, and the relation between the two competencies was also studied. For this research, two different groups of children - one with 48 children who attend English kindergarten and the other with 60 children who attend only Korean kindergarten - took PPVT-R in Korean and in English each. The result shows that children with early English education have more English competency than those without it. No significant differences, however, are found in Korean competency between the two groups. The relation between the two competencies proves positive in children with early English education. It can thus be concluded that the effect of early English education is partially positive on children's language development, which may support the additive bilingualism that children's second language can improve without losing their native language competency. In addition, this result will be able to provide for us the direction and the guideline to the policy of foreign language education and early education.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 한국전기전자재료학회 2005년도 추계학술대회 논문집 Vol.18
• /
• pp.159-160
• /
• 2005

The superconducting fault current limiter(SFCLs) provides the effect such as enhancement in the power system reliability due to limiting fault current in a few miliseconds. The Flux-lock type SFCL using the YBCO film among various type SFCLs consists of the primary and the secondary copper coils that are wound in parallel each other through the iron core. The operation can be controlled by adjusting the inductances and the winging directions of each the coil. We compared the current limiting performance on the additive and the subtractive polarity winding directions in case of an open-loop iron core. To analyze quench characteristics, we experimented various phase angle.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제11권1호
• /
• pp.360-373
• /
• 2017

This paper presents a novel digital video steganalysis scheme against the spatial domain video steganography technology based on a spatial temporal detector (ST_D) that considers both spatial and temporal redundancies of the video sequences simultaneously. Three descriptors are constructed on XY, XT and YT planes respectively to depict the spatial and temporal relationship between the current pixel and its adjacent pixels. Considering the impact of local motion intensity and texture complexity on the histogram distribution of three descriptors, each frame is segmented into non-overlapped blocks that are $8{\times}8$ in size for motion and texture analysis. Subsequently, texture and motion factors are introduced to provide reasonable weights for histograms of the three descriptors of each block. After further weighted modulation, the statistics of the histograms of the three descriptors are concatenated into a single value to build the global description of ST_D. The experimental results demonstrate the great advantage of our features relative to those of the rich model (RM), the subtractive pixel adjacency model (SPAM) and subtractive prediction error adjacency matrix (SPEAM), especially for compressed videos, which constitute most Internet videos.

• Plant Biotechnology Reports
• /
• 제3권4호
• /
• pp.285-292
• /
• 2009

Zoysiagrass (Zoysia japonica) is one of the important turfgrass species. Extending green period of zoysiagrass via delaying leaf senescence will make this species have more potential in the turfgrass industry. In this study, we found that zoysiagrass seedlings treated with $GA_3$ could delay the leaf senescence induced by darkness. To study expression of genes responsive to staying green in zoysiagrass, suppression subtractive hybridization (SSH) was used to identify differentially expressed genes between non-$non-GA_3-treated$ and $GA_3-treated$ seedlings subjected to darkness. A total of 307 ESTs were generated, of which 226 ESTs clustered into 54 contigs and 81 were singlets. Differentially expressed genes selected by subtractions were classified into six categories according to their putative functions generated by BLAST analysis. Expression of five selected genes, Met, SAM, V-ATPase, Cry (Cryptochrome gene), and An (diphthine synthase gene) were examined by RT-PCR and Real-time PCR. Both RT-PCR and Real-time PCR results demonstrated that the differential expressions of these genes were attributable to delaying senescence by exogenously applied gibberellic acid. This is the first genome-wide study of senescence in a species of turfgrass.

• Molecular & Cellular Toxicology
• /
• 제2권3호
• /
• pp.170-175
• /
• 2006

The extensive isolation of genes responsive to stressful conditions from a soft coral Scleronephthya gracillimum was described. Soft coral colonies were exposed to thermal and chemical stressors to induce the expression of stress related genes. Differentially expressed genes by natural or anthropogenic stressors were identified by construction of standard and stress exposed-paired subtractive cDNA library. Thirty-two and thirty-seven kinds of candidate genes were identified from thermal or benzo[a]pyrene stress exposed group, respectively, which are associated with cell cycle, cell signaling, transcription, translation, protein metabolism, and other cellular functions. The expected function of each gene was described. The isolated and identified differentially expressed genes have a great potential to identify environmental stressors in global environmental changes and could act as molecular biomarkers for biological responses against environmental changes. Finally, it may open a new paradigm on soft coral health assessment.

• 정보저장시스템학회:학술대회논문집
• /
• 정보저장시스템학회 2005년도 추계학술대회 논문집
• /
• pp.129-133
• /
• 2005

Data storage related with writing and retrieving requires high storage capacity, fast transfer rate and less access time. Today any data storage system cannot satisfy these conditions, however holographic data storage system can perform faster data transfer rate because it is a page oriented memory system using volume hologram in writing and retrieving data. System can be constructed without mechanical actuating part therefore fast data transfer rate and high storage capacity about $1Tb/cm^3$ can be realized. In this paper, to reduce errors of binary data stored in holographic data storage system, a new method for bit error reduction is suggested. First, find cluster centers using subtractive clustering algorithm then reduce intensities of pixels around cluster centers and fuzzy rules. Therefore, By using this error reduction method following results are obtained ; the effect of Inter Pixel Interference noise is decreased and the intensity profile of data page becomes uniform therefore the better data storage system can be constructed.