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Postembryonic Development of Leucokinin I-Producing Neurons in the Brain of Insect Spldoptera litura

  • Kang, Hyu-No;Lee, Bong-Hee
    • Animal cells and systems
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    • v.1 no.1
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    • pp.107-113
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    • 1997
  • Antisera against the myotropic neuropeptide leucokinin I, originally isolated from head extracts of the cockroach Leucophaea maderae, have been used to investigate the distribution of the leucokinin I-immunoreactive (LK I-IR) neurons in the brain of the common cutworm, Spodoptera Iitura, during postembryonic development. The LK I-IR neurons are found at the larval stages (excluding first instar larval stage), pupal stages, and adult stage, of which the brains have been examined in this experiment. The number of the LK I-IR neurons in the brain increases from the second instar larva to the fifth instar larva which has about 32, the largest number in all postembryonic stages. Thereafter, the LK I-IR neurons begin to decrease in number. During the pupal stages, smaller number of LK I-IR neurons persist in the brains; 6 or 4. At adult stage the brain contains 8 LK I-IR neurons. The LK I-IR cell bodies are distributed in each dorsal cortex of both cerebral hemispheres in the second instar larva and through all the neuromeres of the brain during later larval stages, despite of being a large number of the LK I-IR cell bodies in dorsolateral neuromeres. At pupal stages, most of the LK I-IR cell bodies are found in the pars intercerebralis. Extremely small number of the LK I-IR cell bodies are localized in the pars lateral is. Adult brain contains the LK I-IR cell bodies in the pars intercerebralis and the middle cortex of the posterior brain. The LK I-IR nerve processes can be easily found in the neuropils of almost all the neuromeres in the brains of third, fourth, fifth and sixth instar larvae. Most of the LK I-IR nerve fibers in those brains are originated from the LK I-IR cell bodies located in the brains. The LK I-IR cell bodies which have very weak reactivities to the antisera do not show projection of the LK I-IR nerve processes in the brains.

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Cloning and Expression of the Bdi Methylase Gene in E. coli (대장균 내에서의 Bdi I Methylase 유전자의 클로닝과 발현)

  • 전희숙;김용석;최경래;노현모
    • Korean Journal of Microbiology
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    • v.25 no.1
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    • pp.40-45
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    • 1987
  • The gene for the Bdi I modification enzyme, which is one of Bdi I restriction-modification system, fromBrevibacterium divaricatum FERM 5948 was cloned and expressed in E. coli. For cloning of the Bdi I methylase gene, we have initially used three cloning site(EcoRI, BamHI and Sal I) of plasmid vector pBR 322 and adopted the retransformation method after Bdi I restriction endonuclease cleavage. Selection of transformants carrying the gene was based on the resistance of the modified plasmid encoding the enzyme to cleavage by Bdi I restriction enzyme, and the recombinant plasmid pBDIM 116 containing 5.6kb EcoRI insery was proved to carry the gene. Crude cell extracts prepared from strains carrying the plasmid pBDIM 116 contained an S-adenosylmethionine-dependent methyltransferase activity specific for the Bdi I recognition site, ATCGAT. The restriction map was constructed with 11 restriction enzyme, and the Bdi I restriction-modification system was also discussed.

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Construction Various Recombiant Plasmids for the Enhancement of Glutathione Production in E. coli. (E. coli에서 글루타치온 생산 증가를 위한 재조합 플라스미드의 구성)

  • 남용석;이세영
    • Journal of Life Science
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    • v.7 no.4
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    • pp.253-261
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    • 1997
  • In order to enhance glutathione production, various recombinant plasmids containing gshI and/or gshII genes isolated from E. coli K-12 were constructed and introduced into E. coli. Some plasmids contained one to three copies of gshI genes in pBR325 and others contained both gshI and genes for glutathione biosynthesis. $\gamma$-Glutamylcysteine synthetase activities of E, coli strains amplified tandem repeated gshI genes were dependent on the number of inserted gshI genes. The glutathione productivity of E. coli strains harboring various plasmids was investigated using an E. coli acetate kinase reaction as an ATP regenerating system. The glutathione productivity of E. coli strains harboring tandem repeated gshI genes was increased in proportion to the number of inserted gshI genes. By the introduction of gshII gene, the glutathione productivity of the E. coli was increased by two-fold compared with E. coli strain amplified gshI gene only. The enzymatic production of glytathione in E. coli was mainly affected by the increase of $\gamma$-glutamylcysteine synthetase activity. The highest glutathione productivity was obtained in E. coli strains harboring pGH-501 plasmid containing two copies of gshI and copy of gshII genes in pUC8 vector.

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Expression of Hepatic Vascular Stress Genes Following Ischemiai/Reperfusion and Subsequent Endotoxemia

  • Kim, Sung-Ho;Lee, Sun-Mee
    • Archives of Pharmacal Research
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    • v.27 no.7
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    • pp.769-775
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    • 2004
  • Hepatic ischemia and reperfusion (l/R) predisposes the liver to secondary stresses such as endotoxemia, possibly via dysregulation of the hepatic microcirculation secondary to an imbalanced regulation of the vascular stress genes. In this study, the effect of hepatic I/R on the hepatic vasoregulatory gene expression in response to endotoxin was determined. Rats were subjected to 90 min of hepatic ischemia and 6 h of reperfusion. Lipopolysaccharide (LPS, 1 mg/kg) was injected intraperitoneally after reperfusion. Plasma and liver samples were obtained 6 h after reperfusion for serum aminotransferase assays and RT-PCR analysis of the mRNA for the genes of interest: endothelin-1 (ET-1), its receptors $ET_A$ and $ET_B$, endothelial nitric oxide synthase (eNOS), inducible nitric oxide synthase (iNOS), heme oxygenase-1 (HO-1), cyciooxygenase-2 (COX-2), and tumor necrosis factor-a (TNF-${\alpha}$). The activities of serum aminotransferases were significantly increased in the I/R group. This increase was markedly potentiated by LPS treatment. The ET-1 mRNA was increased by LPS alone, and this increase was significantly greater in both the I/R alone and I/R + LPS groups compared to the sham. There were no significant differences in ETA receptor mRNA levels among any of the experimental groups. $ET_B$ mRNA was increased by both LPS alone and I/R alone, with no significant difference between the I/R alone and I/R + LPS groups. The eN OS and HO-1 transcripts were increased by I/R alone and further increased by I/R + LPS. The iNOS mRNA levels were increased by I/R alone, but increased significantly more by both LPS alone and I/R + LPS compared to I/R alone. The TNF-${\alpha}$ mRNA levels showed no change with I/R alone, but were increased by both LPS alone and I/R + LPS. The COX-2 expression was increased significantly by I/R alone and significantly more by I/R + LPS. Taken collectively, significantly greater induction of the vasodilator genes over the constriction forces was observed with I/R + LPS. These results may partly explain the increased susceptibility of ischemic livers to injury as a result of endotoxemia.

iSCSI Intermediate Target System for Reducing I/O Latency between Mobile Device and Mass Storage (모바일 기기와 대용량 스토리지간의 I/O latency를 줄이기 위한 iSCSI 중개 서버 시스템)

  • Yang Yuan;Choi Wonil;Park Myong-Sun
    • Proceedings of the Korean Information Science Society Conference
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    • 2005.11a
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    • pp.892-894
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    • 2005
  • 모바일 기기가 널리 보급되면서 모바일 기기에서 멀티미디어 데이터나 데이터베이스 같은 대용량 데이터 사용에 대한 요구가 커지고 있다. 따라서 모바일 기기의 저장 공간의 한계를 극복하기 위한 노력의 하나로 iSCSI 를 이용해 모바일 기기에 원격 스토리지 서비스를 제공하는 연구가 진행되었다. 그러나 모바일 기기에 iSCSI 를 적용했을 때, 지연 시간에 민강한 iSCSI의 구조적인 특성 때문에 iSCSI 클라이언트가 서버에서 멀리 떨어진 위치로 이동하게 되면 iSCSI I/O 성능이 급격히 떨어지는 문제가 발생한다. 본 논문에서는 모바일 기기가 스토리지 서버로부터 거리가 멀어졌을 때 전송 지연시간이 증가함에 따라 iSCSI 성능이 급격하게 떨어지는 단점을 개선하기 위해 중개서버(Intermediate Target)를 이용해 iSCSI Target을 지역화하여 성능을 높이는 방안을 제안한다.

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FINITENESS PROPERTIES OF EXTENSION FUNCTORS OF COFINITE MODULES

  • Irani, Yavar;Bahmanpour, Kamal
    • Bulletin of the Korean Mathematical Society
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    • v.50 no.2
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    • pp.649-657
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    • 2013
  • Let R be a commutative Noetherian ring, I an ideal of R and T be a non-zero I-cofinite R-module with dim(T) ${\leq}$ 1. In this paper, for any finitely generated R-module N with support in V(I), we show that the R-modules $Ext^i_R$(T,N) are finitely generated for all integers $i{\geq}0$. This immediately implies that if I has dimension one (i.e., dim R/I = 1), then $Ext^i_R$($H^j_I$(M), N) is finitely generated for all integers $i$, $j{\geq}0$, and all finitely generated R-modules M and N, with Supp(N) ${\subseteq}$ V(I).

Korean Listeners' Perception of English /i/, /I/, and /$\epsilon$/

  • Yun, Yung-Do
    • Speech Sciences
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    • v.12 no.1
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    • pp.75-87
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    • 2005
  • In this study I investigate how native Korean listeners perceive English vowels /i/, /I/, and /$\epsilon$/. I extend Flege et al's (1997) study with synthesized /i/-/I/ and /I/-/$\epsilon$/ continua, and apply the results to Flege's (1995) Speech Learning Model (SLM). The statistical results show that native speakers of English rely more on spectral steps than on vowel duration when they identify the /i/-/I/ continuum, whereas native speakers of Korean rely more on vowel duration than on spectral steps when they identify the same continuum. In the case of the /I/-/$\epsilon$/ continuum, both groups rely on spectral steps when they identify the /$\epsilon$/, which supports the SLM; Koreans identified the /$\epsilon$/ categorically since Korean has the equivalent vowel. However, there was not statistical difference between Korean subjects with more English experience (KE) and those with less English experience in the identification of both continua. This contradicts the SLM, which posits that experienced L2 learners are better than inexperienced L2 learners in perception of L2 sounds. The exact nature of this should be further investigated in the SLM.

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SOME GENERALIZATIONS OF M-FINITE BANACH SPACES

  • Cha, Jae-Sun;Jung, Kap-Hun
    • The Pure and Applied Mathematics
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    • v.3 no.2
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    • pp.155-162
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    • 1996
  • We will show that let X and Y be M -finite Banach spaces with canonical M-decompositions $X{\cong}{{\prod}^{{\gamma}_{\infty}}_{i=1}}{X^{n_i}}_{i}\;and\;Y{\cong}{{\prod}^{{\bar{\gamma}}_{\infty}}_{j=1}}{\tilde{Y}^{m_j}}_{j}$, respectively and M and N nonzero locally compact Hausdorff spaces. Then I : $C_{0}$(M,X) ${\longrightarrow}\;C_{0}$(N,Y) is an isometrical isomorphism if and only if r = $\bar{r}$ and there are permutation and homeomorphisms and continuous maps such that I = ${I^{-1}}_{N.Y}\;{\circ}I_{w}^{-1}{\circ}({{\prod}^{\gamma}}_{i=1}I_{t_i,u_i}){\circ}I_{M,X}$.

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Identification of a Deoxyribonuclease I Inhibitor from a Phage-Peptide Library

  • Choi, Suk-Jung;Sperinde, Jeffrey J.;Szoka, Francis C. Jr.
    • Molecules and Cells
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    • v.19 no.1
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    • pp.54-59
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    • 2005
  • Deoxyribonuclease I (DNase I) is a divalent cation dependent endonuclease and thought to be a significant barrier to effective gene delivery. The only known DNase I-specific inhibitor is monomeric actin which acts by forming a 1:1 complex with DNase I. Its use, however, is restricted because of tendency to polymerize under certain conditions. We screened two random phage peptide libraries of complexity $10^8$ and $10^9$ for DNase I binders as candidates for DNase I inhibitors. A number of DNase I-binding peptide sequences were identified. When these peptides were expressed as fusion proteins with Escherichia coli maltose binding protein, they inhibited the actin-DNase I interaction ($IC_{50}=0.1-0.7{\mu}M$) and DNA degradation by DNase I ($IC_{50}=0.8-8{\mu}M$). Plasmid protection activity in the presence of DNase I was also observed with the fusion proteins. These peptides have the potential to be a useful adjuvant for gene therapy using naked DNA.

NON-EXISTENCE OF SOME ARTINIAN LEVEL O-SEQUENCES OF CODIMENSION 3

  • Shin, Dong-Soo
    • Journal of applied mathematics & informatics
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    • v.23 no.1_2
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    • pp.517-523
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    • 2007
  • Let R/I be an Artinian algebra of codimension 3 with Hilbert function H such that $h_{d-1}>h_d=h_{d+1}$. Ahn and Shin showed that A cannot be level if ${\beta}_{1,d+2}(Gin(I))={\beta}_{2,d+2}(Gin(I))$ where Gin(I) is a generic initial ideal of I. We prove that some certain graded Artinian algebra R/I cannot be level if either ${\beta}_{1,d}(I^{lex})={\beta}_{2,d}(I^{lex})+1\;or\;{\beta}_{1,d+1}(I^{lex})={\beta}_{2,d+1}(I^{lex})\;where\;I^{lex}$ is a lex-segment ideal associated to I.