• Journal of Microbiology and Biotechnology
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• 제19권12호
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• pp.1547-1556
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• 2009

A novel thermostable $\alpha$-glucosidase (TtGluA) from Thermoanaerobacter tengcongensis MB4 was successfully expressed in E. coli and characterized. The TtgluA gene contained 2,253 bp, which encodes 750 amino acids. The native TtGluA was a trimer with monomer molecular mass of 89 kDa shown by SDS-PAGE. The purified recombinant enzyme showed hydrolytic activity on maltooligosaccharides, p-nitrophenyl-$\alpha$-D-glucopyranide, and dextrin with an exotype cleavage manner. TtGluA showed preference for short-chain maltooligosaccharides and the highest specific activity for maltose of 3.26 units/mg. Maximal activity was observed at $60^{\circ}C$ and pH 5.5. The half-life was 2 h at $60^{\circ}C$. The enzyme showed good tolerance to urea and SDS but was inhibited by Tris. When maltose with the concentration over 50 mM was used as substrate, TtGluA was also capable of catalyzing transglycosylation to produce $\alpha$-1,4-linked maltotriose and $\alpha$-1,6-linked isomaltooligosaccharides. More importantly, TtGluA showed exclusive regiospecificity with high yield to produce $\alpha$-1,6-linked isomaltooligosaccharides when the reaction time extended to more than 10 h.

• 한국수학교육학회지시리즈D:수학교육연구
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• 제8권3호
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• pp.123-144
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• 2004

There is a tradition of advocating the 'two basics' (basic knowledge and basic skills) in Chinese mathematics education. The direct consequence is that Chinese students are able to produce excellent performance in the international mathematics examinations and outstanding results in the international mathematics competitions. In this article, we will present why and how Chinese teachers teach the 'two basics,' and how combine the pupil's creativity with their 'two basics.' Open ended problem solving is a way to meet the goal. The following topics will be concerned: Culture background; the speed of computation; 'make perfect' ; Efficiency in classroom; Balance between 'two basics' and personal development. In Particular, Chinese mathematics educators pay more attentions to the link between open ended problem solving and the 'two basics' principal.

• 동의생리병리학회지
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• 제27권5호
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• pp.520-529
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• 2013

Needham Problem(NP) is the influential question that English historian of Chinese science Joseph Needham raised, "Why modern science had not developed in the Chinese civilisation but only in that of Europe?" Our objectives in this paper are as follows: First, we will revisit NP in the broad context of the emergence of modernity rather than treating it just as an internal problem of Chinese science. After that, the problem of modernity in Chinese medicine will be discussed from the viewpoint of NP. After NP's intellectual backgrounds are summarized, its value and implications are examined, and then Needham's own answers are presented. Afterwards, we present supplementary hypotheses, adapted from Weber, as our solution to NP in Chinese science and medicine. Needham thought that the European scientific revolution would not have been possible without the rise of modern capitalism. He also believed that Chinese bureaucratism facilitated early development of Chinese science and in turn, inhibited later radical change by interrupting the rise of capitalism. According to our hypotheses, scientific changes are related to social changes, especially to the legitimation crises, which lead to the alternations of mode of justification in sciences. The Chinese society did not go through the legitimation crises as the European society did, and therefore it failed to produce a radically different kind of justification from the traditional one. This is the reason why there was no revolution in science and medicine in China.

• Journal of Microbiology and Biotechnology
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• 제30권2호
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• pp.206-215
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• 2020

Trichoderma reesei is the major filamentous fungus used to produce cellulase and there is huge interest in promoting its ability to produce higher titers of cellulase. Among the many factors affecting cellulase production in T. reesei, the mycelial phenotype is important but seldom studied. Herein, a close homolog of the Neurospora crassa COT1 kinase was discovered in T. reesei and designated TrCOT1, which is of 83.3% amino acid sequence identity. Functional disruption of Trcot1 in T. reesei by RNAi-mediated gene silencing resulted in retarded sporulation on potato dextrose agar and dwarfed colonies on minimal medium agar plates containing glucose, xylan, lactose, xylose, or glycerol as the sole carbon source. The representative mutant strain, SUS2/Trcot1i, also displayed reduced mycelia accumulation but hyperbranching in the MM glucose liquid medium, with hyphal growth unit length values decreased to 73.0 ㎛/tip compared to 239.8 ㎛/tip for the parent strain SUS2. The hyperbranching phenotype led to slightly but significantly increased cellulase secretion from 24 to 72 h in a batch culture. However, the cellulase production per unit of mycelial biomass was much more profoundly improved from 24 to 96 h.

• 말소리와 음성과학
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• 제8권1호
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• pp.53-62
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• 2016

In this study, we examined whether Chinese learners of Korean can correctly produce the phonological process on the lexical and post-lexical level. For this purpose 4 Korean native speakers and 10 advanced and 10 intermediate Chinese learners of Korean participated in the production test. The materials analyzed constituted 10 Korean sentences in which nasalization can be applied on the syllable boundary, word boundary(w-boundary) as well as accentual phrase boundary(AP-boundary). The results show that for Korean speakers, nasalization was applied 100% at all level whereas for Chinese speakers, the rate of application of nasalization is different according to prosodic constituents and Korean proficiency. Nasalization was more frequently applied at the lexical level than the post-lexical level, and it is more frequent in the w-boundary conditions than in the AP-boundary conditions. However, the rate of nasalization in the w-boundary is close to the lexical level. The pronunciation errors were committed either as non application of nasalization or coda obstruent ommission. In the case of non application of nasalization, Chinese learners of Korean produced the target syllables as underling forms, which were not transformed as surface forms. In addition, we can observe the ommission of coda obstruents in 'lenis obstruents+nasal sound' sequences. As a result, nasalization is blocked by this omission.

• Nuclear Engineering and Technology
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• 제54권10호
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• pp.3614-3619
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• 2022

To operate the ion cyclotron resonance heating (ICRH) antennas in a better heating state and produce relatively low impurities, it is necessary to control the antenna spectrum by changing the antenna phasing. As the electrical length of the antenna feeding transmission lines is changing as a matter of the standing wave pattern at the ceramic supports, 90° elbows, T-connectors and antenna loops, we chose to measure the current at the grounding points of the antenna loops by antenna strap probe. The voltage drops along a small, several millimeter-long paths at the end of the antenna loops give a signal that is proportional to the current in the antenna loop. Through the simulation of the antenna strap probe and the actual measurement of the antenna phasing under vacuum conditions, the reliability of the antenna strap probe based diagnostic system have been successfully proved. Moreover, this system was successfully applied to the ICRH daily experiments in the spring of 2021. In the near future, the active real-time feedback control of the antenna phasing system will be developed based on this diagnostic system in the EAST tokamak.

• 한국진공학회지
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• 제4권S2호
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• pp.30-33
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• 1995

By using X-ray double crystal diffraction technique the multilayer structure composed of glass membrane, platinum film and $\alpha Al_2O_3$ substrate has been studied. It is found the stress is produced in the film by thermal mismatch within multilayer materials. The measuring results of thin film platinum resistors show that the stress were induce resistance change of device and different stress status will produce add resistance in different direction. Selecting proper glass material can make opposite stress in Pt film and opposite add resistance due to thermal mismatch. The reliability of Pt resistor has been improved with method of this stress compensation.

• 한국컴퓨터정보학회:학술대회논문집
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• 한국컴퓨터정보학회 2013년도 제47차 동계학술대회논문집 21권1호
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• pp.271-272
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• 2013

The music with the times, evolved from analogous tape music to digital music. New authoring tools, interfaces, and applications make us to produce high quality music using cheap equipments. Inspired by this concept, we design an classical chinese style-instrument with the audio-visual interactive function. It enables a user to compose music and to see a vivid picture at the same time.

• Journal of Microbiology and Biotechnology
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• 제27권3호
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• pp.439-449
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• 2017

Beauveria bassiana infects a number of pest species and is known to produce insecticidal substances, such as the nonribosomal peptides (NRPs) beauvericin and bassianolide. However, most NRPs and their biological roles in B. bassiana remain undiscovered. To identify NRPs that potentially contribute to pathogenesis, the 21 predicted NRP synthetases (NRPSs) or NRPS-like proteins of B. bassiana ARSEF 2860 were primarily ranked into three functional groups: basic metabolism (7 NRPSs), pathogenicity (12 NRPSs), and unknown function (2 NRPSs). Based on the transcript levels during in vivo growth on diamondback moth (Plutella xylostella (Linnaeus)), half of the Group II NRPSs were likely to be involved in infection. Given that the metabolites biosynthesized by these NRPSs remain to be determined, our result underlines the importance of the NRPSome in fungal pathogenesis, and will serve as a guide for future genomic mining projects to discover functionally essential and structurally diverse NRPs in fungal genomes.

• 동아시아식생활학회지
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• 제18권6호
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• pp.893-898
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• 2008

The of this study was to the abilities of Northeast Asians to discriminate sweetness on foods and their preference sweetness. Panels of Korean, Japanese and Chinese three sample -sucrose solutions, bulgogi, julienned radish salad- in which the sucrose levels had been manipulated to produce five samples of each. The sucrose solutions were prepared 1%, 3%, 5%, 7%, 9% sucrose to the water. Bulgogi and julienned radish salad 3%, 9%, 15%, 21%, 27% sucrose to the recipe. As, the three ethnic groups significant differences in test of sweetness in sucrose solutions(79%). Korean(a=1.164) to be the most sweetness, compared to Japanese(a=1.063) and Chinese(a=0.999). All ethnic groups preferred $3{\sim}7%$ solution, and Korean than Japanese and Chinese. Ethnic groups significant differences in sweetness of the julienned radish salad 21% sucrose. Korean(a=1.054) appeared to be the most able to detect the sweetness, compared to their Japanese(a=0.785) and Chinese(a=0.642). Both Korean and Japanese the strongest preference for the 15% julienned radish salad, the Chinese preferred the 21%. The abilities of ethnic groups to detect the sweetness in bulgogi significant differences high concentration(more than 27%), and the result of regression analysis on the awareness of sweet taste order Korean(a=0.918), Japanese(a=0.832), Chinese(a=0.690). All groups preferred the $9{\sim}21%$ bulgogi the most, Japanese showed higher preference 15% bulgogi than did Korean and Chinese.