• The Plant Pathology Journal
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• v.19 no.1
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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.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.9
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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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• v.18 no.4
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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.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.40 no.6
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• pp.39-47
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• 2003

This paper proposes the new narrow erase method to erase wall charges formed in an AC plasma display panel (PDP) cell. In the Proposed method, sustain switching timing is adjusted for inducing a weak discharge. Then, after the narrow erase, tile voltage of the X electrode is set to differ from that of the Y electrode. For the proposed method, the measured maximum address voltage margin was 38.3V at Y_Reset voltage of 100V and sustain voltage of 180∼185V. However, for the prior method, in which the X and Y electrodes we set to be of equal voltage after the narrow erase, the measured maximum address voltage margin was 31.3V at Y_Reset voltage of 150V and sustain voltage of 180V. This result shows that the measured maximum voltage margin for the proposed method is greater than that for the prior method by ∼7V(22%).

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.16 no.2
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• pp.109-115
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• 2023

In this paper, we demonstrated the orientation characteristics of liquid crystals using UV-treated FSAM as alignment layer. Moreover we confirmed the FSAM properties before and after UV treatment on indium tin oxide (ITO) glass substrates using physicochemical analysis. The hydrophobic property of the FSAM surface is change to hydrophilic through UV treatment. After UV treatment the LC molecules also were uniformly and horizontally aligned on the FSAM surfaces and the pretilt angle was obviously changed 90° degrees to 0° degrees. EO characteristic of TN cell which was fabricated with UV-treated FSAM was faster response time compare to conventional PI layer. The FSAM before and after UV treatment has a superior application potential as the LC alignment layer for LCD, potentially replacing the conventional polyimide layer.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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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.

• Journal of Life Science
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• v.15 no.1 s.68
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• pp.118-123
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• 2005

For the expression in Saccharomyces cerevisiae, Bacillus stearothermophilus cyclodextrin glucano­transferase gene (cgtS) in pCGTS (4.8 kb) was subcloned into the surface expression vector, pYD1 (GALl promoter). The constructed plasmid, pYDCGT (7.2 kb) was introduced into S. cerevisiae EBY100 cells, and then yeast transformants were selected on the synthetic defined media lacking tryptophan. The formation of cyclodextrin (CD) was confirmed with active staining of culture broth of transformant grown on starch medium. Enzymatic reaction products with respect to the culture time and the reaction time were examined by TLC analysis. The results indicated that the enzyme activity was exhibited after 12 h cultivation and CD was produced after 10min of enzymatic reaction. When the surface-engineered yeast cells were cultured on galactose medium, maximum activities of CGTase were about 21.3 unit/l and 16.5 unit/l at $25^{\circ}C\;and\;30^{\circ}C$, respectively. The plasmids stability showed about $80\%\;even\;at\;25^{\circ}C\;and\;30^{\circ}C$.

• Molecules and Cells
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• v.25 no.1
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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.

• The Journal of the Korean Society for Microbiology
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• v.21 no.2
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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.

• Korean Journal of Metals and Materials
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• v.47 no.1
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• pp.44-49
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• 2009

Indium tin oxide(ITO) thin films were deposited on the glass substrates by radio-frequency (RF) magnetron sputtering method. The influence of rapid thermal annealing (RTA) treatment on the optical and electrical properties of the films were investigated for the purpose of fabricating plasma display signboard. Structural properties, surface roughness, sheet resistance and transmittance of the ITO film were analysed by using x-ray diffraction method, atomic force microscopy (AFM), four point prove, and ultraviolet-visible spectrometer, respectively. It was found that the RTA treatment increased the transmittance and decreased the resistivity of the ITO film, respectively. Furthermore, we successfully demonstrated the direct-current plasma signboard by using ITO electrode and phosphors.