• Journal of the Institute of Electronics Engineers of Korea SD
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• v.44 no.5
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• pp.36-41
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• 2007

We report the 94 GHz CPW branch-line bandpass filter for planar integrated millimeter-wave circuits. The branch-line coupler operates as a transversal filtering section by connecting the coupling ports to the open load stubs and taking the isolation port as the output node. For design of the 94 GHz branch-line bandpass filter, we built the CPW library and optimized the characteristic impedances and the lengths of the branch-line coupler and the open load stubs. The fabricated 94 GHz bandpass filter exhibits an insertion loss of 2.5 dB with an 11.7 % 3 dB relative bandwidth and the return loss is -18.5 dB at a center frequency of 94 GHz.

• Journal of Microbiology
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• v.43 no.3
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• pp.313-318
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• 2005

In this study, we demonstrate the use of a PCR-based method for the detection of the specific genes involved in natural-product biosynthesis. This method was applied, using specifically designed PCR primers, to the amplification of a gene segment encoding for sedo-heptulose 7-phosphate cyclase, which appears to be involved in the biosynthetic pathways of $C_7N$ aminoacyclitol or its keto analogue-containing metabolites, in a variety of actinomycetes species. The sequences of DNA fragments (about 540 bp) obtained from three out of 39 actinomycete strains exhibited a high degree of homology with the sedo-heptulose 7-phosphate cyclase gene, which has been implicated in acarbose biosynthesis. The selective cultivation conditions of this experiment induced the expression of these loci, indicating that the range of $C_7N$ aminoacyclitol or its keto analogue-group natural products might be far greater than was previously imagined. Considering that a total of approximately 20 $C_7N$ aminoacyclitol metabolites, or its keto analogue-containing metabolites, have been described to date, it appears likely that some of the unknown loci described herein might constitute new classes of $C_7N$ aminoacyclitol, or of its keto analogue-containing metabolites. As these metabolites, some of which contain valienamine, are among the most potent antidiabetic agents thus far discovered, the molecular detection of specific metabolite-producing actinomycetes may prove a crucial step in current attempts to expand the scope and diversity of natural-product discovery.

• Korean Journal of Microbiology
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• v.38 no.4
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• pp.203-203
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• 2002

Cytomegalovirus (CMV), a beta-herpesvirus with worldwide distribution, exhibits host persistence, a distinguishing characteristic of all herpesviruses. This persistence is dependent upon restricted gene expression in infected cells as well as the ability of productively infected cells to escape from normal cell-mediated anti-viral immunosurveillance. Type I (IFN-α/β) and type II (IFN-γ) interferons are major components of the innate defense system against viral infection. They are potent inducers of MHC class I and II antigens and of antigen processing proteins. Additionally, IFNS mediate direct antiviral effects through induction effector molecules that block viral infection and replications such as 2′, 5-oligoadenylate synthetase (2, 5-OAS). IFNS function through activation of well-defined signal transduction pathways that involve phosphorylation of constituent proteins and ultimate formation of active transcription factors. Recent studies have shown that a number of diverse viruses, including CMV, EBV, HPV mumps and Ebola, are capable of inhibiting IFN-mediated signal transduction through a variety of mechanisms. As an example, CMV infection inhibits the ability of infected cells Is transcribe HLA class I and II antigens as well as the antiviral effector molecules 2, 5-OAS and MxA I. EMSA studies have shown that IFN-α and IFN-γ are unable to induce complete signal transduction in the presence of CMV infection, phenomena that are associated with specific decreases in JAKl and p48. Viral inhibition of IFN signal transduction represents a new mechanistic paradigm for increased viral survival, a paradigm predicting widespread consequences in the case of signal transduction factors common to multiple cytokine pathways.

• Korean Journal of Microbiology
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• v.38 no.4
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• pp.218-218
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• 2002

Using two drugs, tunicamycin and brefeldin A, which affect protein processing, we investigated the intracellular processing mechanism of secreted aspartyl proteinase 1 (SAPl) of Candide albicans. Three intracellular forms of SAPI were detected by immunoblotting using menoclonal antibody (MAb) CAPl. Their molecular weights were approximately 40, 41 and 45 kDa, respectively. The 41 kDa protein is a glycoprotein and may be the same as the extracellular form judging by its molecular mass. The 40 kDa protein was the unglycosylated form and its molecular mass coincided with deglycosylated SAPl and the 45 kDa protein was also the unglycosylated form. Neither the 40 and 45 kDa proteins were detected in the culture supernatant of C. albicans. These suggested that the 40 and 45 kDa proteins might be intracellular precursor forms of SAPI. These results show that SAPI is translated as a 45 kDa precusor form in the endoplasmic reticulum and the 45 kDa precursor farm undergoes proteolytic cleavage after translocation into the Golgi apparatus, generating the 40 kDa precursor form. This 40 kDa precursor is converted into a 41 kDa mature form through glycosylation in the Golgi apparatus. The mature form of the 41 kDa protein is sorted into secretary vesicles and finally released into the extracellular space through membrane fusion. When the glycan region of SAPl was digested with N-glycosidase F, both stability and activity of the enzyme decreased. These results indicate that the glycan attached to the enzyme may, at least in parti be related to enzyme stability and activity.

• Korean Journal of Microbiology
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• v.38 no.4
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• pp.270-270
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• 2002

Pathogenic Salmonella typhimurium can invade the intestinal epithelium and cause a wide range of diseases including gastroenteritis and bacteremia in human and animals. To identify the genes involved in the infection, the invasion determinant was obtained from S. typhimurium 82/6915 and was subcloned into pGEM-7Z. A subclone DHl (pSV6235) invaded HEp-2 and Chinese hamster ovary epithelial cells and contained a 4.4 kb fragment of S. typhimurium genomic region. Compared with the host strain E. coli DHl, the subclone DHl (pSV6235) invaded cultured HEp-2 and Chinese hamster ovary cells at least 75- and 68-fold higher, respectively. The invasion rate of E. coli DHl for the cells significantly increased by harbouring the genomic region derived from pathogenic S. typhimurium 82/6915.

• Korean Journal of Microbiology
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• v.38 no.4
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• pp.230-230
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• 2002

Class Ⅲ chitin synthases in filamentous fungi are important for hyphal growth and differentiation of several filamentous fungi. A genomic clone containing the full gene encoding Chs4, a class Ⅲ chitin synthase in Penicillium chrysogenum, was cloned by PCR screening and colony hybridization from the genomic library. Nucleotide sequence analysis and transcript mapping of chs4 revealed an open reading frame (ORF) that consisted of 5 exons and 4 introns and encoded a putative protein of 915 amino acids. Nucleotide sequence analysis of the 5′flanking region of the ORF revealed a potential TATA box and several binding sites for transcription activators. The putative transcription initiation site at -716 position was identified by primer extension and the expression of the chs4 during the vegetative growth was confirmed by Northern blot analysis. Amino acid sequence analysis of the Chs4 revealed at least 5 transmembrane helices and several sites for past-transnational modifications. Comparison of the amino acid sequence of Chs4 with those of other fungi showed a close relationship between P chrysogenum and genus Aspergillus.

• Korean Journal of Microbiology
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• v.38 no.4
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• pp.255-255
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• 2002

For rapid and sensitive measurement of antiviral activities, application of a recombinant virus containing firefly luciferase gene was attempted. Recombinant human cytomegalovirus (HCMV) containing luciferase gene driven by HCMV late gene pp28 promoter (HCMV/pp28-luc) was used to test the antiviral activities of three known compounds and the result was compared with results from the conventional plaque assay for measuring the production of infectious viruses. When human fibroblast cells were infected with HCMV/pp28-luc, luciferase activity was observed at 2 days after infection and reached maximum at 6 days after infection, whereas the production of infectious virus was maximal at 4 days after infection. The antiviral activities of ganciclovir, acyclovir, and papaverine were measured in HFF cells infected with HCMV/PP28-luc and the luciferase activity was compared with the infectious virus titers. Luciferase activity decreased as the concentration of ganciclovir or papaverine increased, while there was a slight decrease in luciferase activity with acyclovir. The level of the decrease in Luciferase activity was comparable to the level of decrease in the production of infectious virus. Therefore, the antiviral assay using recombinant virus HCMV/pp28-luc resulted in sensitivity similar to the conventional plaque assay with a significant reduction in assay time.

• Journal of Microbiology and Biotechnology
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• v.32 no.8
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• pp.960-966
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• 2022

Lactic acid bacteria (LAB) exert antagonistic activity against root-knot nematodes, mainly by producing organic acids via carbohydrate fermentation. However, they have not yet been used for root-knot nematode (Meloidogyne incognita) control owing to a lack of economic feasibility and effectiveness. In this study, we aimed to isolate organic acid-producing LAB from kimchi (Korean traditional fermented cabbage) and evaluated their nematicidal activity. Among the 234 strains isolated, those showing the highest nematicidal activity were selected and identified as Lactiplantibacillus plantarum WiKim0090. Nematicidal activity and egg hatch inhibitory activity of WiKim0090 culture filtrate were dose dependent. Nematode mortality 3 days after treatment with 2.5% of the culture filtrate was 100%, with a 50% lethal concentration of 1.41%. In pot tests, the inhibitory activity of an L. plantarum WiKim0090-copper sulfate mixture on gall formation increased. Compared to abamectin application, which is a commercial nematicide, a higher control value was observed using the WiKim0090-copper sulfate mixture, indicating that this combination can be effective in controlling the root-knot nematode.

• Journal of the Korea Safety Management & Science
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• v.17 no.4
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• pp.343-352
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• 2015

This study analyzes the business performance of research and development(R&D) and especially studies the effect of technology management activity and technology innovation competency on commercialization performance. According to previous studies, the technology management activity can be composed of technological innovativeness, analysis of market, R&D method, and appropriateness for commercialization plan. Also, the technology innovation can be divided into patent, R&D manpower, R&D investment ratio, production capability, and marketing capability. On the result of the analysis, all the components of technology management activity are positively related with commercialization performance. In case of technology innovation competency, however, only production and marketing capabilities have influence on the business performance. Especially, marketing capability controls the effect of technology management activities on the commercialization performance. Consequently, technology management is very important activity for SMEs to succeed commercialization and SMEs should collaborate with production and marketing departments from the early stage of R&D.

• The Journal of the Convergence on Culture Technology
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• v.10 no.3
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• pp.519-531
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• 2024

The purpose of this study is to analyze the aspects and characteristics of educational innovation planned and implemented at the university site targeting universities in Busan, Ulsan, and Gyeongnam, and to explore their limitations and tasks. For this purpose, we analyzed the contents of innovation strategy programs among the plans of 17 universities in the national innovation support projects in Busan, Ulsan, and Gyeongnam area. First, the university innovation strategy was divided into input, process, infrastructure, and other factors, and among them, the process factor was divided into education, research, and industry-university cooperation to examine the aspects and characteristics of innovation. As a result of the study, the aspects of university innovation at universities in Busan, Ulsan, and Gyeongnam were analyzed in the areas of education, research, and industry-academia cooperation. Characteristics of innovation were emphasis on convergence education, competency development, smart system foundation, introduction of innovative teaching and learning techniques, consumer-centeredness, and regional linkage. The limitations and tasks of university innovation revealed through the research are as follows. First, a specialized university innovation business structure should be prepared in consideration of the context of local universities. Second, established strategies with high innovativeness must be implemented and sustained, and consensus among members is required for this. Third, the innovation of universities should not mean the centralization of academics, and the role and efforts of universities as a research institutions should be improved. Fourth, it should not be overlooked that more important than the visible innovation strategy of university innovation is the education innovation that occurs directly to students as a result of the education effect.