• The Plant Pathology Journal
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• 제19권1호
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• pp.30-33
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• 2003

The chestnut blight fungus, Cryphonectria parasitica, and its hypovirus aye a useful model system in the study of the mechanisms of hypoviral infection and its consequences, such as a biological control of fungal pathogens. Strains containing the double-stranded (ds) RNA viruses Cryphonectria hypovirus 1 show characteristic symptoms of hypovirulence and display hypovirulence-associated changes, such as reduced pigmentation, sporulation, laccase production, and oxalate accumulation. Interestingly, symptoms caused by hypoviral infection appear to be the result of aberrant expression of a number of specific genes in the hypovirulent strain. Several viral regulated fungal genes are identified as cutinase gene, Lac1, which encodes an extracellular laccase, Crp, which encodes an abundant tissue-specific cell-surface hydrophobin that mediates physical strength, and Mf2/1 and Mf2/2, which encode pheromone genes involved in poor sporulation in the presence of hypo-virus. Since the phenotypic changes in the fungal host are pleiotropic, although coordinated and specific, it has been suggested that the hypovirus disturbs one or several regulatory pathways (Nuss,1996). Accordingly, several studies have shown the implementation of a signal transduction pathway during viral symptom development. Although further studies are required, hypovirulence and its associated symptom development due to the hypoviral regulation of a fungal hetero-trimeric G-protein have been suggested. In addition, recent studies have shown the presence of a novel protein kinase gene cppk1 and its transcriptional upregulation by hypovirus. In this review, the presence of important components in signal transduction pathway, their putative biological function, and viral-specific regulation will be addressed.

• 한국기계가공학회지
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• 제20권9호
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• pp.84-89
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• 2021

Indium tin oxide (ITO) transparent electrodes, which are used to manufacture organic light-emitting diodes, are used in light-emitting surface electrodes of display EL panels such as cell phones and TVs, liquid crystal panels, transparent switches, and plane heating elements. ITO is a major component that consists of indium and tin and is advantageous in terms of obtaining sheet resistance and light transmittance in a thin film. However, the optical performance of devices decreases with an increase in its thickness. A digital holography system was constructed and measured for the step measurement of the ITO thin film, and the reliability of the technique was verified by comparing the FE-SEM measurement results. The error rate of the step difference measurement was within ±5%. This result demonstrated that this technique is useful for applications in advanced MEMS and NEMS industrial fields.

• Journal of Microbiology and Biotechnology
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• 제18권4호
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• pp.616-623
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• 2008

In spite of an increasing interest in fucoidans as biologically active compounds, no convenient commercial sources with fucoidanase activity are yet available. A marine bacterial strain that showed confluent growth on a minimal medium containing fucoidan, prepared from Korean Undaria pinnatifida sporophylls, as the sole carbon source was isolated and identified based on a 16S rDNA sequence analysis as a strain of Sphingomonas paucimobilis, and named Sphingomonas paucimobilis PF-1. The strain depolymerized fucoidan into more than 7 distinct low-molecular-mass fucose-containing oligosaccharides, ranging from 305 to 3,749 Da. The enzyme activity was shown to be associated with the whole cell, suggesting the possibility of a surface display of the enzyme. However, a whole-cell enzyme preparation neither released the monomer L-fucose from the fucoidan nor hydrolyzed the chromogenic substrate p-nitrophenyl-${\alpha}$-L-fucoside, indicating that the enzyme may be an endo-acting fucoidanase rather than an ${\alpha}$-L-fucosidase. Therefore, this would appear to be the first report on fucoidanolytic activity by a Sphingomonas species and also the first report on the enzymatic degradation of the Korean Undaria pinnatifida sporophyll fucoidan. Moreover, this enzyme activity may be very useful for structural analyses of fucose-containing polysaccharides and the production of bioactive fucooligosaccharides.

• 전자공학회논문지SC
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• 제40권6호
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• pp.39-47
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• 2003

본 논문에서는 세폭소거 방식에 관한 연구를 하였으며, 종래에는 세폭소거 이후 전극에 벽전하가 쌓이지 않게 하기 위해 X전극과 Y전극의 전압 레벨을 같게 하여 벽전하를 소거한 반면, 본 논문에서는 세폭소거 이후 X전극과 Y전극의 전압 레벨을 다르게 하고 유지구간에서 스위치의 펄스 타이밍을 조절하여 약한 방전을 일으키게 한 뒤 벽전하를 소거하였다. 실험결과 종래의 방식은 Y_Reset 전압이 150V, 서스테인 전압이 180V일 때 어드레스 전압 마진이 31.3V로 가장 크게 나타났다. 본 논문에서 제안한 방식은 Y_Reset 전압이 100V, 서스테인 전압이 180V, 185V일 때, 어드레스 전압 마진이 38.3Y로 가장 크게 나타났다. 본 논문에서 제안한 방식으로 인하여 종래의 방식 보다 약 7V(22%)정도의 전압마진을 더 확보할 수가 있었다.

• 한국정보전자통신기술학회논문지
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• 제16권2호
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• pp.109-115
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• 2023

본 논문은 UV(ultraviolet) 처리된 자기 조립 단분자막(fluorinated self-assembled monolayers; FSAM)을 배향막으로 사용한 액정의 배향 특성을 분석하였다. 물리화학적 분석을 사용하여 UV 처리 전후의 ITO(indium-tin-oxide) 유리 기판의 FSAM 특성을 확인하였다. FSAM 표면은 UV 처리에 의해 소수성에서 친수성으로 변화하였다. LC(liquid crystal) 분자는 UV 처리된 FSAM 표면에서 수평방향으로 정렬되었고 선경사각도 90°에서 0°로 변화하였다. UV 처리된 FSAM을 배향막으로 사용하여 제작된 TN(twist nematic) 셀의 전기광학(electro optics; EO) 특성은 기존의 PI(polyimide) 배향막에 비해 응답 시간이 빠른 것을 확인하였다. 이는 UV 처리된 FSAM 이 LCD(liquid crystal display)의 기존 폴리이미드 배향막을 대체할 잠재적인 가능성을 가진다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 추계학술대회 논문집
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• pp.111-114
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• 1999

Electroluminescence(EL) devices based on organic thin films have been attracted lots of interests in large-area light-emitting display. In this stuffy, an emissive layer was fabricated using Langmuir-Blodgett(LB) technique in organic light-emitting (OLEDs). This emissive organic material was synthesized and named PECCP[poly(3.6-N-2-ethylhexyl carbazolyl cyanoterephthalidene)] which has a strong electron donor group and an electron acceptor group in main chain repeated unit. This material has good solubility in common organic solvents such as chloroform. THF, etc, and has a good stability in air. The Langmuir-Blodgett(LB) technique has the advantage of precise control of the thickness down to the molecular scale, In particular, by varying the film thickness it is possible to investigate the metal/polymer interface. Optimum conditions for the LB film deposition are usually determined by investigating a relationship between a surface pressure $\pi$ and an effective are A occupied by one molecule on the subphase. The LB films were deposited on an indium-tin-oxide(ITO) glass at a surface pressure of 10 mN/m and dipping speed of 12 mm/min after spreading PECCP solution on distilled water surphase at room temperature, Cell structure was ITO/PECCP LB film/Alq$_3$/Al. We considered PECCP as a hole -transport layer inserted between the emissive layer and ITO. We also used Alq$_3$ as an emissive layer and an electron transport layer. We measured current-voltage(I-V) characteristics, UV/visible absorption, PL spectrum and EL spectrum of the OLEDs.

• 생명과학회지
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• 제15권1호
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• pp.118-123
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• 2005

B. stearothermophilus 유래의 CGTase 유전자(cgtS)를 보유하고 있는 재조합 plasmid pCGTS (4.8 kb)을 효모 표면 발현용 vector인 pYDl (GAL1 promoter)에 subcloning 하였다. 구축된 재조합 plasmid, pYDCGT (7.2 kb)는 S. cerevisiae EBY100에 형질전환하였고, tryptophan이 결여된 SD 배지에서 1차 선별된 형질전환체들을 YPGS배지에서 배양 후 활성 염색을 통하여 CD가 생 성 됨을 확인하였다. 배양시간과 효소반응시간에 따른 반응 산물을 TLC로 분석 한 결과, 배양 12시간째부터 효소활성이 나타났고, 반응 10분 이후부터 CD가 생성되어 시간이 지남에 따라 CD 생성양이 증가하는 것을 확인하였다. 회분 배양한 결과 $25^{\circ}C$와 $30^{\circ}C$에서 CGTase의 최대 활성이 각각 21.3 unit/1 와 16.5 unit/1로 나타났고, plasmid 안정성은 각각 $86\%$와 $82\%$로 나타나 배양온도에 상관없이 plasmid는 비교적 안정하게 유지되었다.

• Molecules and Cells
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• 제25권1호
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• pp.78-85
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• 2008

In a search for new molecular pathways associated with asthma, we performed an mRNA differential display analysis using total RNA extracted from the tracheal tissues of ovalbumin (OVA)-challenged mice and sham controls. cDNAs corresponding to mRNAs for which expression levels were altered by OVA-challenge were isolate and sequenced. Twenty-eight genes differentially expressed in sham and OVA challenged mice were identified. A GenBank BLAST homology search revealed that they were related to cytoskeleton remodeling, transcription, protein synthesis and modification, energy production, and cell growth and differentiation. Two were selected for further characterization. Up-regulation of both the perinatal skeletal myosin heavy chain (skMHC) and fast skeletal muscle myosin light chain (skMLC) genes was confirmed by RT-PCR of trachea tissue from OVA challenged mice. Overexpression of skMLC protein was observed in the smooth muscle layers of OVA-challenged mice by immunohistochemistry, and the surface areas stained with skMLC antibody increased in the OVA-challenged mice. The overexpression of skMLC in murine asthma may be associated with the changes of bronchial smooth muscle.

• 대한미생물학회지
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• 제21권2호
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• pp.171-179
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• 1986

The HLA class II region encodes a series of polymorphic glycoproteins that form cell surface heterodimers each consisting of one $\alpha$ and one $\beta$ chain. Thess class II molecules are encoded by genes clustered within three loci. DP, DQ, and DR are functfonally implicated as regulatory signals in intercellular communication during the immune resposes. The phenotypic hallmark of the HLA complex is a high degree of structural and functional polymorphism. Detailed analysis. of such polymorphisms should aid in understanding the molecular basis for associations between HLA and diseases. We have used techniques of restriction enzyme fragment analysis by Southern blotting to investigate polymorphisms associated with DQ $\beta$ class II genes on haplotypes expressing the HLA-DR4 and -DQw3 specificities. The endonucleases Hind III and Bam HI were used to identify a specific DQ $\beta$ genomic polymorphism that precisely corrresponds with the reactivity of a monoclonal antibody A-10-83, previously shown to define a serologic split of DQw3. This study identifies two allelic DQ va. riants. DQw3.1 and DQw3.2. We used these specific genotypic markers to investigate the genomic basis of the association of DR4 with insulin-dependent diabetes mellitus(IDDM) and seropositive juvenile rheumatoid arthritis(JRA). The DR4 positive IDDM demonstrate the predominant expression of DQw3.2 and the very rare expression of DQw3.l. However, in haplotype matched siblings from two IDDM families, all of the DR4 positive siblings display a IDDM-associated DQw3.2 allele. Thus, both affected and healthy individuals can carry the same haplotypes and genomic markers, demonstrating that thess specific allelic variants are genetic elements that indicate a increased risk of IDDM but are not in fact disease specific. We contrasted this result with a similar analysis of patients with another DR4-associated disease, JRA. In contrast to the preponderance of the DQw3.2 allele in IDDM, the JRA patients expressed either the DQw3.1 or the DQw3.2 allele and sometimes both, without apparent association with disease expession. The different genomic markers reported here within HLA-DQ region potentially an analysis of HLA-associated function and disease susceptibility.

• 대한금속재료학회지
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• 제47권1호
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• pp.44-49
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• 2009

본 연구에서는 2인치 ITO의 타깃으로 ITO박막을 성장시킨 후 RTA 처리로 인한 전기적, 광학적 특성의 변화를 조사하였으며, RTA 처리된 ITO 박막을 이용하여 플라즈마 응용 사인보드를 제작 및 구동하였다. RTA공정으로 열처리한 ITO는 투과도는 증가하며, 비저항은 감소함을 관찰하였으며, 투과도의 증가는 RTA로 인한 결정성의 증가로 인한 결과이고, 비저항의 감소는 결정성의 증가와 더불어 치환형 주석의 원자수가 증가하였다고 사료된다. ITO를 이용하여 사인보드 제작시 방전cell의 압력은 3-5 Torr가 적당함을 알 수 있었으며, 전극 간격을 조절하여 120 V 정도의 낮은 플라즈마 개시 전압을 갖는 플라즈마 응용 사인보드를 성공적으로 제작 할 수 있었다.