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Characterization and Purification of Acidocin 1B, a Bacteriocin Produced by Lactobacillus acidophilus GP1B

  • Han, Kyoung-Sik;Kim, Young-Hoon;Kim, Sae-Hun;Oh, Se-Jong
    • Journal of Microbiology and Biotechnology
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    • 제17권5호
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    • pp.774-783
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    • 2007
  • In the present study, acidocin 1B, a bacteriocin produced by Lactobacillus acidophilus GP 1B, exhibited profound inhibitory activity against a variety of LAB and pathogens, including Gram-negative bacteria, and its mode of action was to destabilize the cell wall, thereby resulting in bactericidal lysis. Acidocin 1B was found to be heat stable, because it lost no activity when it was heated up to $95^{\circ}C$ for 60 min. It retained approximately 67% of the initial activity after storage for 30 days at $4^{\circ}C$, and 50% of its initial activity after 30 days at $25^{\circ}C$ and $37^{\circ}C$. The molecular mass of acidocin 1B was estimated to be 4,214.65 Da by mass spectrometry. Plasmid curing results indicated that a plasmid, designated as pLA1B, seemed to be responsible for both acidocin 1B production and host immunity, and that the pLA1B could be transformed into competent cells of L. acidophilus ATCC 43121 by electroporation. Our findings indicate that the acidocin 1B and its producer strain may have potential value as a biopreservative in food systems.

L대역 불요파 저감을 위한, UHF대역 CRLH 대역통과 여파기와 소형 대역저지 여파기의 결합 설계 (Design of a Compact Bandstop Filter-combined UHF-band CRLH Bandpass Filter to Suppress the Spurious in L-band)

  • 엄다정;강승택;목세균;송충호;우춘식;박도현
    • 전기학회논문지
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    • 제61권1호
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    • pp.104-109
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    • 2012
  • In this paper, we propose a way to improve the quality of L-band wireless communication from unfriendly influential factors lying in the neighboring RF bands. The UHF-band system has resonator components and they generate harmonics as the spurious in the L-band. Therefore, a metamaterial CRLH bandpass filter is designed for the purpose of system miniaturization and smaller insertion loss, and its spurious phenomenon is observed in the frequency domain. And its harmonics in the L-band are suppressed by a compact bandstop filter whose equivalent circuit is newly developed. The design methodology is validated by the equivalent circuit to be compared with commercial full-wave EM software simulations, where the spurious is dropped by 20dB. Also, the advantage of the proposed design is presented by the comparison where our filter is much smaller than the conventional parallel edge coupled filter by over 50%, with excellent harmonic suppression.

Uterotrophic Assays of Pyrethroid Insecticides in Immature Rats

  • Kim, Soon-Sun;Rhee, Gyu-Seek;Lee, Rhee-Da;Kwack, Seung-Jun;Lim, Kwon-Jo;Yhun, Hyo-Jung;Park, Kwang-Sik;Park, Kui-Lea
    • 한국독성학회:학술대회논문집
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    • 한국독성학회 2003년도 추계학술대회
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    • pp.149-149
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    • 2003
  • It is well known that many pesticides possess hormonal activity, and thus have been classified as endocrine disruptors. Currently, pyrethroid insecticides are in worldwide use to control in door pests, providing potential for environmental exposure. A few studies of hormonal activities of these pyrethroid insecticides, however, have been reported, and are controversial between studies.(omitted)

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Development of transgenic rice lines expressing the human lactoferrin gene

  • Lee, Jin-Hyoung;Kim, Il-Gi;Kim, Hyo-Sung;Shin, Kong-Sik;Suh, Seok-Cheol;Kweon, Soon-Jong;Rhim, Seong-Lyul
    • Journal of Plant Biotechnology
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    • 제37권4호
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    • pp.556-561
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    • 2010
  • Lactoferrin is an 80-kDa iron-binding glycoprotein that is found in high concentrations in human milk. Human lactoferrin (hLF) has several beneficial biological activities including immune system modulation and antimicrobial activity. In the present study, we devolved a method of hLF expression through introducing the hLF gene construct into Oriza sativa cv. Nakdong using the Agrobacterium-mediated transformation system. The expression of the hLF gene under the control of the rice glutelin promoter was detected in the seeds of transgenic rice plants. Transformed rice plants were selected on media containing herbicide(DL-phosphinothricin) and the integration of hLF cDNA was confirmed by Southern blot analysis. The expression of the full length hLF protein from the grains of transgenic rice plants was verified by Western blot analysis. The lactoferrin expression levels in the transformed rice grains determined by enzyme-linked immunosorbant assay accounted for approximately 1.5% of total soluble protein. Taken together, these data indicate that rice grains expressing hLF can be directly incorporated into infant formula and baby food.

A Study on Fatigue Damage Modeling Using Neural Networks

  • Lee Dong-Woo;Hong Soon-Hyeok;Cho Seok-Swoo;Joo Won-Sik
    • Journal of Mechanical Science and Technology
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    • 제19권7호
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    • pp.1393-1404
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    • 2005
  • Fatigue crack growth and life have been estimated based on established empirical equations. In this paper, an alternative method using artificial neural network (ANN) -based model developed to predict fatigue damages simultaneously. To learn and generalize the ANN, fatigue crack growth rate and life data were built up using in-plane bending fatigue test results. Single fracture mechanical parameter or nondestructive parameter can't predict fatigue damage accurately but multiple fracture mechanical parameters or nondestructive parameters can. Existing fatigue damage modeling used this merit but limited real-time damage monitoring. Therefore, this study shows fatigue damage model using backpropagation neural networks on the basis of X -ray half breadth ratio B / $B_o$, fractal dimension $D_f$ and fracture mechanical parameters can estimate fatigue crack growth rate da/ dN and cycle ratio N / $N_f$ at the same time within engineering limit error ($5\%$).

Backbone NMR assignments of a putative secretory protein from Helicobacter pylori, using a high-field (900 MHz) NMR

  • Sim, Dae-Won;Ahn, Hee-Chul;Won, Hyung-Sik
    • 한국자기공명학회논문지
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    • 제13권2호
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    • pp.108-116
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    • 2009
  • The HP0902, a homodimeric 22.1 kDa protein, has been suggested as a putative secretory protein from Helicobacter pylori, although the protein possesses no signal peptide for secretion. Since it may be associated with the virulence of the bacterium, NMR study has been initiated in terms of structural genomics. In our previous effort to assign the backbone NMR resonances, using 800MHz NMR machine at pH 7.8, the resonances from eight of the 99 residues could not be assined due to missing of the signals. In this work, to enhance the extent of assignments, a 900 MHz machine was employed and the sample pH was reduced down to 6.5. Finally, almost all signals, except for those from G9 and S24, could be clearly assigned. The determined secondary structure using the assined chemical shifts indicated that the HP0902 consists of 11 ${\beta}$-strands with no helices. In our database search result, HP0902 was predicted to interact with VacA (Vacuolating cytotoxin A), which is a representative virulence factor secreted from Helicobacter pylori. Thus, molecular interaction between HP0902 and VacA would be worthy of investigation, on the basis of the present results of NMR assignments.

확률적 방법에 의한 크리프 균열성장 계수의 분포 추정 (Estimation for the Distribution of Creep Crack Growth Coefficients by Probabilistic Assessment)

  • 이상호;윤기봉;최병학;민두식;안종석;이길재;김선화
    • 대한금속재료학회지
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    • 제48권9호
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    • pp.791-797
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    • 2010
  • The creep crack growth rate (da/dt) of the Cr-Mo steels tested by pre-crack and the voltage (or resistance) variables were related into fracture parameter (Ct), crack growth coefficient (H), and an exponent (q) in the parts of Base, weld and HAZ. The fracture parameter (Ct) has various variables relating to the specimen and crack shape, applied stress, and creep strain curve. The H and q was inferred by OLS regression (ordinary least square method), and the H values were solved in statistics and probability assessment, which were attained fromPDF's distributions (probability density function). The HAZ part has the highest value of q by OLS regression and the widest distribution of H by PDF of WEIBULL, which means that the crack sensitivity of HAZ should be cautioned against the creep crack growth and failure.

Molecular Cloning and Characterization of Very Late Expression Factor 1 Gene, vlf-1 from Bombyx mori Nuclear Polyhedrosis Virus Kl

  • Park, Hye-Jin;Lee, Kwang-Sik;Cho, Eun-Sook;Yun, Eun-Young;Kang, Seok-Woo;Kim, Keun-Young;Sohn, Hung-Dae;Jin, Byung-Rae
    • International Journal of Industrial Entomology and Biomaterials
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    • 제1권1호
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    • pp.29-33
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    • 2000
  • We cloned and characterized a very late expression factor 1 gene, vlf-1, which regulates the level of very late gene transcripts, from Bombyx mori nuclear polyhedrosis virus (BmNPV) K1 strain. The 1,140 bp vlf-1 has an open reading frame of 379 amino acid and a MW of 44 kDa. The vlf-1 nucleotide sequence of BmNPV-Kl showed high homology with Autographa californica nuclear polyhedrosis virus and BmNPV T3 strain so far known, and its deduced amino acid residues were identical to those of BmNPV T3. The location of vlf-1 in the BmNPV-Kl genome was confirmed by Southern blot analysis and its expression patterns at the transcriptional level were confirmed by Northern hybridization analysis.

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클라우드 서비스를 위한 레고형 초고화질 영상 송수신 미디어 플랫폼 설계 제안 (A Design Proposal of a Lego-type UHD(Ultra High Definition) Media Platform for Cloud Services)

  • 구성완;정다희;김현식;서정욱
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2014년도 춘계학술대회
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    • pp.655-657
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    • 2014
  • 본 논문은 클라우드 서비스를 위한 초고화질 영상 송수신 미디어 플랫폼인 레고형 UHD(Ultra High Definition) 미디어 플랫폼을 제안한다. 이 플랫폼을 이용하면 옥/내외 환경에서 UHD 영상을 이용할 수 있는 클라우드 서비스를 자유롭게 공유할 수 있고, 차세대 무선 통신기술(802.11ac, LTE Broadcast 등)이 적용된 다양한 미디어 제품과 제안된 플랫폼을 활용한다면 누구나 손쉽게 개발시킬 수 있으며, 다양한 비즈니스 모델에 적용할 수 있어 새로운 시장과 산업 창출을 기대 할 수 있을 것으로 생각한다.

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White spot syndrome virus (WSSV)의 VP28에 대한 단클론 항체 생산 (Production of monoclonal antibodies against VP28 of white spot syndrome virus (WSSV))

  • 방지형;김위식;김춘섭;김종오;오명주
    • 한국어병학회지
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    • 제32권1호
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    • pp.45-48
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    • 2019
  • We developed and subsequently characterized mouse monoclonal antibodies (MAbs) against recombinant VP28 structural protein (rVP28) of white spot syndrome virus (WSSV). We established six hybridoma clones secreting MAbs against rVP28: 15A11, 20G6, 31H2, 34H6, 38D1 and 43A1. All six MAbs recognized the 25 kDa of protein in gill homogenates of WSSV-infected shrimp by western blot analysis, while no reactivity was observed in gill homogenates of normal shrimp. Moreover, high enzyme-linked immunosorbent assay (ELISA) optical density (OD) values (0.8-2.68) were observed in the hemolymphs from WSSV-infected shrimp, while low OD values (less than 0.24) were recorded in the hemolymphs from normal shrimp, by using these six MAbs produced in this study. These results suggest that these six MAbs are useful for the detection of WSSV.