• Title/Summary/Keyword: $\delta$-integration

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Novel SSF Process for Ethanol Production from Microcrystalline Cellulose Using the $\delta$-Integrated Recombinant Yeast, Saccharomyces cerevisiae L2612$\delta$GC

  • Cho, Kwang-Myung;Yoo, Young-Je
    • Journal of Microbiology and Biotechnology
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    • v.9 no.3
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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.

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Development of three dimensional variable-node elements and their applications to multiscale problems (삼차원 다절점 유한요소의 개발과 멀티스케일 문제의 적용)

  • Lim, Jae-Hyuk;Sohn, Dong-Woo;Im, Se-Young
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2008.04a
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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.

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Construction of Amylolytic Industrial Strains of Saccharomyces cerevisiae for Improved Ethanol Production from Raw Starch (생전분으로부터 에탄올 생산이 증진된 전분 분해성 산업용 Saccharomyces cerevisiae의 개발)

  • Im, Young-Kum;Park, Jin-Yeong;Lee, Ja-Yeon;Choi, Seung-Hyun;Chin, Jong-Eon;Ko, Hyun-Mi;Kim, Il-Chul;Bai, Suk
    • Korean Journal of Microbiology
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    • v.49 no.2
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    • pp.200-204
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    • 2013
  • To contruct amylolytic industrial strains of Saccharomyces cerevisiae which produce ethanol efficiently from raw starch, the Bacillus amyloliquefaciens ${\alpha}$-amylase genes (Amy) or Aspergillus awamori glucoamylase genes (GA1) was separately introduced into the ribosomal DNA loci in the chromosomes of the raw starch fermenting-parental strain (ATCC 9763/$YIp{\delta}AGSA{\delta}$), using double 18S rDNA-integration system. Ethanol production after 3 days of fermentation by the strain that produced ethanol most efficiently from raw starch (ATCC 9763/$YIp{\delta}AGSA{\delta}$/YIpAG2rD) among the transformant strains was 1.5-times higher than that by the parental strain. This new strain generated 9.2% (v/v) ethanol (72 g/L) from 20% (w/v) raw corn starch and consumed 75% of the raw starch content during the same period.

Early Linguistic Developments of Simultaneous Bilateral Cochlear Implantees (양이 동시 인공와우 사용자의 조기 언어발달)

  • Suh, Michelle J.;Lee, Hyun-Jin;Choi, Hyun Seung
    • Korean Journal of Otorhinolaryngology-Head and Neck Surgery
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    • v.61 no.12
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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.

Characterization of Achlya bisexualis $\beta$-Amylase Expression in an Amylolytic Industrial Strain of Saccharomyces cerevisiae (전분 분해성 산업용 Saccharomyces cerevisiae에서 Achlya bisexualis $\beta$-Amylase의 발현 특성 규명)

  • Lee, Ok-Hee;Lim, Mi-Hyeon;Kim, Ji-Hye;Ryu, Eun-Hye;Ko, Hyun-Mi;Chin, Jong-Eon;Bai, Suk
    • Korean Journal of Microbiology
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    • v.44 no.3
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    • pp.264-269
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    • 2008
  • To develop an amylolytic industrial yeast strain producing $\beta$-amylase, the BAMY gene encoding Achlya bisexualis $\beta$-amylase was constitutively expressed under the control of the alcohol dehydrogenase gene promoter (ADC1p) in an industrial strain of Saccharomyces cerevisiae. Yeast transformation was carried out by an integration system containing $\delta$-sequences as the recombination site. The integrative cassette devoid of bacterial DNA sequences was constructed that contains the BAMY gene and $\delta$-sequences. Industrial S. cerevisiae transformed with this integrative cassette secreted 45 kDa $\beta$-amylase into the culture medium. The $\beta$-amylase activity of the transformant was approximately 18.5-times higher than that of A. bisexualis. The multi-integrated BAMY genes in the transform ant were stable after 100 generations of growth in nonselective medium. Hydrolysis of soluble starch and various starches with the enzyme released maltose but not glucose or oligosaccharides.

Development of Cellobiose-utilizing Recombinant Yeast for Ethanol Production from Cellulose Hydrolyzate

  • Pack, Seung-Pil;Cho, Kwang-Myung;Kang, Hyen-Sam;Yoo, Young-Je
    • Journal of Microbiology and Biotechnology
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    • v.8 no.5
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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.

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$Ba[Ce_{0.9}Y_{0.1}]O_{3-\delta}$ - Ni Composite Membrane for Hydrogen Separation by Aerosol Deposition Method (에어로졸 증착법[aerosol depostion method]에 의한 $Ba[Ce_{0.9}Y_{0.1}]O_{3-\delta}$ - Ni 수소분리막 제조)

  • Park, Young-Soo;Byeon, Myeong-Seob;Choi, Jin-Sub;Kim, Jin-Ho;Hwang, Kwang-Taek
    • Transactions of the Korean hydrogen and new energy society
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    • v.21 no.2
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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.

Flux Linkages Ratio-Based Transformer Protection (쇄교자속비를 이용한 변압기 보호)

  • 강용철;이병은;김은숙;원성호
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.52 no.11
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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.

Structural Studies on Cyclic Compounds. Substituent Effects on the Reducing Ability of Dihydropyridines

  • Koh Park, Kwang-Hee;Moon, Gyeoung-Un;Kwon, Ki-Sung
    • Bulletin of the Korean Chemical Society
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    • v.8 no.3
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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.

Expression of Recombinant Erythropoietin Gene in Transgenic Tobacco Plant (형질전환 담배 식물체에서 재조합 erythropoietin 유전자의 발현)

  • CHOI, Jang Won;PARK, Hee Sung
    • Korean Journal of Plant Tissue Culture
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    • v.24 no.1
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    • pp.63-69
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    • 1997
  • Erythropoietin (EPO) is a glycoprotein that mediates the growth and differentiation of erythroid progenitors. In order to produce recombinant human erythropoietin in tobacco plant, the EPO genomic DNA (5.4 kb) was cloned into plant expression vectors, pBI$\Delta$GUS121, pBD$\Delta$GUS121 and pPEV-1, and introduced in Nicotiana tabacum (var. Xanthi) via Agrobacterium tumefaciens-mediated transformation. After selection on MS media containing kanamycin (Km), 10 Km-resistant plants were obtained per each construct. The correct integration of EPO genomic DNA in the genome of transgenic plant was confirmed by polymerase chain reaction (PCR). Northern blot showed that transcripts of 1.8 kb length were produced in leaves of the plants, but there was no difference of mRNA amount according to promoter number and 5'-untranslated sequence (UTS). The proteins obtained from leaves of transgenic plants were immunologically detected by Western blot using rabbit anti-human EPO polyclonal antibody. The expressed protein appeared as smaller band of apparent mass of 30 kDa as compared to the EPO protein from human urine (37 kDa), suggesting that the modification (glycosylation) system in tobacco plant might be different from that of mammalian cells.

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