• Journal of Microbiology and Biotechnology
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• 제9권3호
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• pp.340-345
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• 1999

A novel simultaneous saccharification and fermentation (SSF) process from the microcrystalline cellulose to ethanol was developed by using $\delta$-integrated recombinant cellulolytic Saccharomyces cerevisiae L2612$L2612\deltaGC$, which can utilize cellulose as carbon and energy sources. The optimum amount of enzymes needed for the efficient conversion of cellulose to ethanol at $30^{\circ}C$ was determined with commercial cellulolytic enzymes. By fed-batch cultivation, the heterologous cellulolytic enzymes were accumulated up to 42.67% of the total cellulase and 29% of the $\beta$-glucosidase needed for the efficient SSF process. When this $\delta$-integrated recombinant yeast was applied to the successive SSF step for ethanol production, 20.35 g/l of ethanol was produced after 12 h from 50 g/l of microcrystalline cellulose. By using this novel SSF process, a considerable amount of commercial enzymes was reduced.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2008년도 정기 학술대회
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• pp.172-176
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• 2008

In this paper, three dimensional linear conforming variable-finite elements are presented with the aid of a smoothed integration (a class of stabilized conforming nodal integration), for mnltiscale mechanics problems. These elements meet the desirable properties of an interpolation such as the Kronecker delta condition, the partition of unity condition and the positiveness of interpolation function. The necessary condition of linear exactness is fully relaxed by employing the smoothed integration, which renders us to meet the linear exactness in a straightforward manner. This novel element description extend the category of the conventional finite elements space to ration type function space and give the flexibility on the number of nodes of element which are fixed in the conventional finite elements. Several examples are provided to show the convergence and the accuracy of the proposed elements, and to demonstrate their potential with emphasis on the multiscale mechanics problems such as global/local analysis, nonmatching contact problems, and modeling of composite material with defects.

• 미생물학회지
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• 제49권2호
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• pp.200-204
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• 2013

생전분으로부터 에탄올을 효율적으로 생산하는 전분 분해성 산업용 Saccharomyces cerevisiae를 제조하기 위해 생전분을 발효하는 모균주(ATCC 9763/$YIp{\delta}AGSA{\delta}$)의 염색체내 ribosomal DNA loci에 double 18S rDNA-integration 시스템을 이용하여 Bacillus amyloliquefaciens ${\alpha}$-amylase 유전자(Amy) 혹은 Aspergillus awamori glucoamylase 유전자(GA1)를 다중도입시켰다. 얻어진 형질전환 균주들 중 생전분으로부터 가장 효율적으로 에탄올을 생산하는 균주(ATCC 9763/$YIp{\delta}AGSA{\delta}$/YIpAG2rD)의 발효 3일째 에탄올 생산은 모균주에 비해 1.5배 높았다. 이 새로운 균주는 생옥수수 전분이 20% (w/v) 함유된 배지에서 3일간 발효를 통해 에탄올 9.2% (v/v) (72 g/L)를 생산하였고, 생전분 함유량의 75%를 소비하였다.

• Korean Journal of Otorhinolaryngology-Head and Neck Surgery
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• 제61권12호
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• pp.650-657
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• 2018

Background and Objectives The present study aimed to compare receptive and expressive language development in children who have undergone simultaneous bilateral cochlear implantation (SCI) and those who have undergone bimodal stimulation (unilateral CI+ hearing aid). Subjects and Method In a retrospective analysis of clinical data, 15 pediatric patients who have received SCI and nine patients who have received bimodal stimulation (BM group) were enrolled. CI was performed for all patients at 24 months of age. Category of Auditory Performance (CAP) scores, Infant-Toddler Meaningful Auditory Integration Scale (IT-MAIS) scores, and developmental quotients (DQ) for expressive and receptive language were compared between the groups at 12 month of follow-up. The Percentage of Consonants Correct (PCC) of children evaluated at 4 years old was also compared. Results At 12 months of follow-up, significantly greater improvements in CAP scores (${\Delta}4.25{\pm}0.5$) were noted in the SCI group compared to the BM group (${\Delta}3.56{\pm}0.88$, p=0.041). Significantly greater improvements in IT-MAIS scores were also noted in the SCI group (${\Delta}36.17{\pm}4.09$) than in the BM group (${\Delta}30.17{\pm}2.91$, p=0.004). The DQ of receptive language was higher in the SCI group than in the BM group ($87.6{\pm}15.4%$ vs. $75.5{\pm}12.0%$, p=0.023) at 12 months of follow-up. Moreover, early SCI was associated with better receptive language skills. PCC index of children at 4 years old was higher in the SCI group than in the BM group ($88.5{\pm}13.2%$ vs. $62{\pm}15.8%$, p=0.014). Earlier SCI was associated with even greater improvements. Conclusion Bilateral SCI is associated with significant improvements in language development when compared with bimodal stimulation. Earlier SCI was associated with better outcomes.

• 미생물학회지
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• 제44권3호
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• pp.264-269
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• 2008

$\beta$-Amylase를 생산하여 전분 분해능을 갖는 산업용 효모를 개발하기 위해 산업용 Saccharomyces cerevisiae에서 Achlya bisexualis $\beta$-amylase (BAMY)유전자를 ADC1 promoter에 연결하여 구성적으로 발현시켰다. 효모의 형질전환은 $\delta$-서열을 재조합 부위로 하는integration 시스템을 이용하였다. Integration 시스템의 세균 유전자 부분은 제거되고 BAMY 유전자와 $\delta$-서열을 갖고 있는 짧은integrative cassette를 제조하였다. BAMY 유전자를 발현하는 재조합 S. cerevisiae 형질전환체는 세포외 배지로 45 kDa의 $\beta$-amylase를 분비하였고, $\beta$-amylase 활성은 A. bisexualis에 비해 약 18.5배 높았다. 형질전환체에 다중도입된 BAMY 유전자는 비선택배지에서 100세대 생장 후에도 안정되게 유지되었다. 각종전분을 기질로 했을 매 $\beta$-amylase의 활성은soluble starch를 기질로 했을 경우와 유사하게 높았고, 가수분해산물 분석 결과 maltose가 주 분해산물이었다.

• Journal of Microbiology and Biotechnology
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• 제8권5호
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• pp.441-448
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• 1998

A cellobiose-utilizing recombinant yeast having $\beta$-glucosidase activity was developed for ethanol production from a mixture of glucose and cellobiose. Using $\delta$-sequences of Tyl transposon of yeast as target sites for homologous recombination, a heterologous gene of $\beta$-glucosidase was integrated into the chromosome of Saccharomyces cerevisiae. The $\delta$-integrated recombinant yeast, Saccharomyces cerevisiae L2612 (Pb-BGL), showed perfect mitotic stability even in nonselective media and showed ca. 1.5 fold higher $\beta$-glucosidase activity than the recombinant yeast harboring the $2\mu$-based plasmid vector system. A mathematical model was developed to describe the $\beta$-glucosidase formation and ethanol production from the Saccharomyces cerevisiae L2612 ($p\delta-BGL$). The model newly described that the heterologous $\beta$-glucosidase production mediated by ADH1 promoter is regulated by glucose and repressed by ethanol.

• 한국수소및신에너지학회논문집
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• 제21권2호
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• pp.117-122
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• 2010

BCY($Ba(Ce_{0.9}Y_{0.1})O_{3-\delta}$) oxide, shows high protonic conductivity at high temperatures, and are referred to as hydrogen separation membrane. For high efficiency of hydrogen separation ($H_2$ flux and selectivity) and low fabrication cost, ultimate thin and dense BCY-Ni layer have to be coated on a porous substrate such as $ZrO_2$. Aerosol depostion (AD) process is a novel technique to grow ceramic film with high density and nano-crystal structure at room-temperature, and would be applied to the fabrication process of AD integration ceramic layer effectively. XRD and SEM measurements were conducted in order to analyze the characteristics of BCY-Ni membrane fabricated by AD process.

• 대한전기학회논문지:전력기술부문A
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• 제52권11호
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• pp.655-660
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• 2003

This paper describes a transformer protective relaying algorithm based on the ratio of increments of flux linkages (RIFL) of the primary and secondary windings. The algorithm uses integration approximation. The RIFL is equal to the turns ratio for all operating conditions except for an internal fault. For a single-phase transformer and a Y-Y transformer, the increments of flux linkages (IFL) are calculated. For a Y-$\Delta$ transformer, the difference of IFL are calculated to use the line currents rather than the delta winding currents, which are unavailable. Their ratios are compared with the turns ratio. The comparative study between the proposed and conventional differentiation approximation methods was conducted. The test results show that the algorithm reduces the approximation errors of the conventional methods.

• Bulletin of the Korean Chemical Society
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• 제8권3호
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• pp.168-170
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• 1987

The reaction between 1-benzyl-3-carbamoyl-1,4-dihydropyridine (BNAH) 1 and various 1-arylpyridinium salts 2, and the reaction between 1-(4-methylphenyl)-1,4-dihydropyridine 4b and 1-aryl-3-carbamoylpyridinium (1-arylnicotinamide) salts 5 were carried out. The extents of reaction in equilibrium were estimated by nmr integration data. The equilibrium constants for the reactions, K, and the standard Gibbs free energy changes for the reduction of the pyridinium salts to the corresponding 1,4-dihydropyridines ${\Delta}G^{\circ}'$ were evaluated. The Hammett plot of log K for the reaction between 1 and 2, and ${\Delta}G^{\circ}'$ against ${\sigma}_p$ of the substituents in 1-aryl moiety shows linear correlation with the reaction constant ${\rho}$ of 9.4 (for log K vs ${\sigma}_p$) and -54.5 KJ/mole (for ${\Delta}G^{\circ}'$ vs ${\sigma}_p$). It was found that 1-aryl-1,4-dihydropyridines have much higher reducing power than the corresponding 1-aryl-1,4-dihydronicotinamides, and the power is affected greatly by the electron-withdrawing ability of the substituents in aryl group. The reactions were utilized for preparation of 1,4-dihydropyridines bearing highly electron-withdrawing groups such as 4-nitrophenyl and 2,4-dinitrophenyl, which could not be obtained by conventional dithionite reduction of the corresponding pyridinium salts due to the base-labile nature of the salts.

• 식물조직배양학회지
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• 제24권1호
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• pp.63-69
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• 1997

Erythropoietin(EPO)은 적혈구 모세포의 분화와 성장을 중재하는 당단백질이며 담배 식물체에서 재조합 사람 EPO를 생산하기 위해 CaMV 35S promoter를 갖는 발현 vector인 pBI$\Delta$GUS121, pBD$\Delta$ GUS121, pPEV-1을 이용하여 5.4kb의 EPO genomic DNA를 cloning 하였고 Agrobacterium tumefaciens에 의한 형질전환에 의해 Nicotiana tabacum (var. Xanthi)으로 도입되었다. Kanamycin을 포함하는 MS 배지에서 각각의 construct에 대하여 10 km 저항성 식물체들이 얻어졌다. 형질전환된 식물체의 게놈에 EPO genomic DNA의 정확한 결합은 polymerase chain reaction에 의해 332bP의 DNA 조각에 의해 확인되었으며 Northern blot 결과 1.8 kb의 전사체들이 식물체 잎에서 발현 축적되는 것이 확인되었다. Promoter의 수나 5'-UTS 서열에 의한 mRNA 양에는 변화가 없었지만 식물체 게놈에 결합된 위치 및 copy number에 의해 mRNA 수준에 영향을 주는 것으로 밝혀졌다. EPO 항체를 이용한 Western blot 결과 식물체에서 발현된 EPO 단백질의 크기는 동물세포에서 발현된 37kDa 보다 작은 30 kDa 이었다. 이는 식물체에서 modification(glycosylation) system은 동물세포에서와는 다르다는 것을 보여준다.