• Title/Summary/Keyword: letters and expressions

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Query Rewriting and Indexing Schemes for Distributed Systems based on the Semantic Web (시맨틱 웹 기반의 분산 시스템을 위한 질의 변환 및 인덱싱 기법)

  • Chae, Kwang-Ju;Kim, Youn-Hee;Lim, Hae-Chull
    • Journal of KIISE:Computing Practices and Letters
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    • v.14 no.7
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    • pp.718-722
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    • 2008
  • Ontology plays an important role of the Semantic Web to describe meaning and reasoning of resources. Ontology has more rich expressive power through OWL that is a next standard representation language recommended by W3C. As the Semantic Web is widely known, an amount of information resources on the Web is growing rapidly and the related information resources are placed in distributed systems on the Web. So, for providing seamless services without the awareness of far distance, efficient management of the distributed information resources is required. Especially, sear ching fast for local repositories that include data related to user's queries is important to the performance of systems in the distributed environment. In this paper, first, we propose an index structure to search local repositories related to queries in the distributed Semantic Web. Second, we propose a query rewriting strategy to extend given user's query using various expression of OWL. Through the proposed index and query strategy, we can utilize various expressions of OWL and find local repositories related to all query patterns on the Semantic Web.

Molecular Cloning of a Thermostable $\alpha$-Amylase Gene from Bacillus stearothermophilus and Its Expressions in E. coli (Bacillus stearothermophilus의 열안정성 $\alpha$-amylase 유전자의 E. coli내에서의 cloning과 발현)

  • Huh, Tae-Lin;Koh, Suk-Hoon;Lee, Se-Yong
    • Microbiology and Biotechnology Letters
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    • v.13 no.4
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    • pp.349-354
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    • 1985
  • A 4.7 kb Hind III fragment containing $\alpha$-amylase gene of Bacillus stearothermophilus IAM 11062 was cloned in Escherichia coil HB101, using plasmid pBR322 and runaway plasmid pSY343 as a vector. The cloned gene was stably maintained and expressed In E.coli. The constructed strain of E. coli have at least 3 times higher amylase activity than the donor strain, of B. stearothermophilus. About 75% of the $\alpha$-amylase produced by the constructed strain of E. coli was localized in the periplasm and it was found that the enzymes can be released by an osmotic shock using EDTA. The enzymatic properties of L-amylase produced in E. coli were very similar to those produced by B. stearothermophilus in terms of optimum temperature, heat stability and molecular weight.

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Influence of High Light and Nitrate Deprivation on the Carotenoid Biosynthesis in Haematococcus pluvialis (고광도와 질소 결핍이 Haematococcus pluvialis의 색소 생합성에 미치는 영향)

  • Yun, Ji-Hyun;Kwak, In-Kyu;Jin, Eon-Seon
    • Microbiology and Biotechnology Letters
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    • v.35 no.4
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    • pp.292-297
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    • 2007
  • The unicellular green alga, Haematococcus pluvialis used as a biological production system for astaxanthin. It accumulates large amounts of the red ketocarotenoid astaxanthin when exposed to various environmental stress such as active oxygen species and high light intensities. To induce astaxanthin biosynthesis of H. pluvialis, cells were incubated in either nitrate free at $25^{\circ}C$ under continuous high light intensity ($1,000\;{\mu}mol$ photons $m^{-2}s^{-1}$) for 2 days or high light stress only. Expressions of astaxanthin biosynthetic genes such as carotenoid hydroxylase, IPP isomerase and ${\beta}$-carotene ketolase were monitored under different culture conditions by using real time RT-PCR. All the subjected genes increased their expression under highlight and N-deprivation condition where a large amount of astaxanthin was accumulated.

Chemotactic Effect of Leukotactin-1/CCL15 on Human Neutrophils

  • Lee Ji-Sook;Yang Eun-Ju;Ryang Yong-Suk;Kim In-Sik
    • Biomedical Science Letters
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    • v.12 no.3
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    • pp.145-151
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    • 2006
  • Leukotactin-l (Lkn-l )/CCL15 has been known as a potent chemoattractant of leukocytes. However, the precise function of Lkn-l in human neutrophils has not been explained well. In the present study, we investigated the contribution of Lkn-1 in chemotactic activity of human neutrophils. Both CCR1 and CCR3 mRNA expressions are strongly expressed in human neutrophils but CCR2 protein expression was uniquely detected on the cell surface. Lkn-l binding to CCR1 and CCR3 induced chemotactic activity of neutrophils. Chemotactic index of Lkn-l was comparable to that of IL-8. $MIP-1{\alpha}/CCL3$ binding to CCR1 and CCR5 has no effect on neutrophil migration. Cell migration, in response to Lkn-l, was blocked by pertussis toxin (Ptx), a $G_o/G_i$ protein inhibitor, and U73122, a phospholipase C(PLC) inhibitor but not by protein kinase C inhibitor such as rottlerin, and Ro-31-8425. Taken together, our results demonstrate that Lkn-l transduces the chemotaxis signal through $G_o/G_i$ protein and PLC. This finding provides the molecular mechanism by which Lkn-l may contribute to neutrophil movement into the site of inflammation.

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Isolation of Putative in vivo Hoxc8 Downstream Target Genes Using ChIP-Cloning Method

  • Chung, Hyun-Joo;Kang, Myeng-Mo;Kim, Myoung-Hee
    • Biomedical Science Letters
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    • v.14 no.1
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    • pp.47-53
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    • 2008
  • Hox genes are known to be transcription factors controlling vertebrate pattern formation along the anteroposterior body axis by regulating many target gene expressions during vertebrate embryogenesis. In order to isolate in vivo Hox responsive target genes, ChIP-cloning technique has been applied using Hoxc8 antibody. Here murine embryo of day 11.5 post coitum (E11.5) highly expressing Hoxc8 gene was used after removing head and tail portions where Hoxc8 is rarely expressing. After fixation with formaldehyde, the chromatin DNAs harboring bound proteins were isolated. After sonication, about 0.5- to 1 Kb chromatin DNAs were immunoprecipitated with anti Hoxc8 antibody. After removing the bound proteins with proteinase K, DNAs were isolated, cloned into the pBluescsript II SK vector, and then sequenced. Total 33 random clones sequenced were anlalyzed to be located at 12 different genomic regions. Among these, 8 turned out to be introns and 4 were intergenic regions localized in random chromosomes. The base composition of total cloned genomic sequences (6608 bp) were AT-rich, i.e., 40% GC. When the Hoxc8 core binding sites, such as TAAT, ATTA, TTAT, and ATAA were analyzed total number of 55, 45, 54, and 55 were found, respectively, which are than twice as many as expected number of 26. Although this in silico analysis does not mean that the ChIP-cloned sequence is real Hoxc8 regulatory element in vivo, these results strongly imply that the DNA fragments cloned through chromatin immunoprecipitation could be very much likely the putative Hoxc8 downstream target genes.

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Chemotactic Effect of the House Dust Mite Allergen, Dermatophagoides pteronyssinus on Human Monocytic THP-1 Cells

  • Yang, Eun-Ju;Lee, Ji-Sook;Yun, Chi-Young;Kim, In-Sik
    • Biomedical Science Letters
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    • v.15 no.1
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    • pp.93-96
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    • 2009
  • House dust mites (HDMs) play an important role in the occurrence of allergic diseases such as asthma and atopic dermatitis. Dermatophagoides pteronyssinus (Der p) is one of the most prevalent HDMs. It mediates the activation of T cells and monocytes, and induces the elevation of immunoglobulin E levels in allergic diseases. However, the effects of Der p on human monocytes have not been fully understood. In the present study, we investigated whether or not Der p has a great effect on the chemotactic activity of the human monocytic cell line, THP-1 cells, as induced by CC chemokines. We also show that the Der p extract (DpE) increased the chemotactic activity of THP-1 cells in response to MCP-1, RANTES, MIP-1${\alpha}$, and TARC, but had no effect on the expressions of CC chemokine receptors (CCRs) binding to CC chemokines in THP-1 cells. Protease inhibitors, such as aprotinin and E64, blocked the increased chemotaxis, while cytoplasmic $Ca^{2+}$ influx mediated by these chemokines was inhibited by DpE. These results indicate that DpE increases the chemotactic activity of THP-1 cells in response to CC chemokines by regulating the cells' protease-dependent mechanism. This finding may be useful in identifying the pathogenesis of allergic diseases induced by Der p.

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An analysis of algebraic thinking of fourth-grade elementary school students (초등학교 4학년 학생들의 대수적 사고 분석)

  • Choi, Ji-Young;Pang, Jeong-Suk
    • Communications of Mathematical Education
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    • v.22 no.2
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    • pp.137-164
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    • 2008
  • Given the importance of early experience in algebraic thinking, we designed six consecutive lessons in which $4^{th}$ graders were encouraged to recognize patterns in the process of finding the relationships between two quantities and to represent a given problem with various mathematical models. The results showed that students were able to recognize patterns through concrete activities with manipulative materials and employ various mathematical models to represent a given problem situation. While students were able to represent a problem situation with algebraic expressions, they had difficulties in using the equal sign and letters for the unknown value while they attempted to generalize a pattern. This paper concludes with some implications on how to connect algebraic thinking with students' arithmetic or informal thinking in a meaningful way, and how to approach algebra at the elementary school level.

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Analysis on letter and expressions in the elementary mathematics textbooks (초등수학 교과서에 제시된 문자와 식 내용 분석 -6차와 2007년 교육과정을 중심으로-)

  • Kim, Sung Ae;Kim, Sung Joon
    • Journal of Elementary Mathematics Education in Korea
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    • v.17 no.1
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    • pp.105-128
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    • 2013
  • One of the biggest changes in 2007 Curriculum Revision is introduction of letter, equation, direct proportion and inverse proportion in fifth and sixth grade of mathematics. The purpose of this study is to provide some implications about teaching-learning method for introduction of letters, teaching and learning activities of equation between the 6th Curriculum and 2007 Curriculum Revision. The below conclusions were drawn from findings obtained in this study. First, the letter and expression were learned in fifth and sixth grade until 6th Curriculum and were learned in seventh grade in middle school of 7th Curriculum. But letter, equation are introduced in 2007 Curriculum Revision again. The overall contents of letter and expression were learned on the 'Relationship' domain in the 6th Curriculum, it were learned on the 'Letter and expression' domain in the 7th Curriculum and is learned on the 'Regularity and problem-solving' domain in the 2007 Curriculum Revision. Second, teaching method of these contents was to promise some definitions at first and then to solve exercises in the 6th Curriculum. But leaning was forced to improve student's problem-solving in the 7th Curriculum. To reduce student's pressure offers at a minimum mathematics terms and to provide problem situations to students who contact daily, it is emphasized on learner's communication in the 2007 Curriculum Revision. We want to be easily connected elementary mathematics and higher mathematics through this study about letter, equation. We recognized how we teach the letter and expression to reduce misconceptions and draw a transition from arithmetic thinking to algebraic thinking and want to be continue of another studies.

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TGF-$\alpha$, -$\beta$$_1$, and bFGF mRNA Expression of Lens Epithelial Cells in Senile and Diabetic Cataract

  • Hwang, Bum-Noon;Her, Jun
    • Biomedical Science Letters
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    • v.8 no.3
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    • pp.127-135
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    • 2002
  • Anterior subcapsular cataract was developed by opacification with transdifferentiation and abnormal proliferation of lens epithelial cells (LECs) and pathological accumulation of extracellular matrix (ECM). After-cataract also be caused by a similar transdifferentiation of LECs remaining after surgery and the accompanying increase of ECM deposits. It is blown that prostaglandin E2 and cytokine, such as TGF-$\beta$, bFGF, and IL-1, were associated with abnormal proliferation and transdifferentiation of LECs. The aim of this study was to detect the expression of transforming growth factor-$\alpha$ (TGF-$\alpha$), transforming growth factor-$\beta_1$(TGF-$\beta_1$) and basic fibroblast growth factor (bFGF) in LECs of senile and diabetic cataract. The expressions of these growth factors in lens epithelial cells were determined. The sample for growth factor determination were collected in senile cataract patients without metabolic disorder, especially diabetes mellitus and diabetic cataract patients. The mRNA expression of growth factors was detected by semi-quantitative reverse transcription - polymerase chain reaction (RT-PCR) followed by Southern blot analysis. Statistics were analysed using Wilcoxon rank sum test. Semi-quantitative RT-PCR/southern analysis of RNA obtained from thirty surgical specimens demonstrated that the level of mRNA expression of TGF-$\alpha$, -$\beta_1$ and bFGF was increased in diabetic cataract lens tissues compared with senile cataract specimens but non-significant, bFGF and TGF-$\beta_1$ mRNA expression were detected in most patients, expression level of TGF-$\beta_1$ was most high on the basis of normal ocular concentration. Detection rate of TGF-$\alpha$ in diabetic cataract was 1.5 fold higher than in senile cataract (P=0.098). TGF-$\alpha$, TGF-$\beta_1$, and bFGF mRNA expression of LECs were detected in senile and diabetic cataract. In both patient groups, expression level of TGF-$\beta_1$, mRNA was high, so We suggest TGF-$\beta_1$ strong influence in development of senile cataract and of diabetic cataract also. TGF-$\alpha$ expression level was similar but more frequently detected in diabetic cataract than in senile cataract. In conclusion, TGF-$\alpha$ may be associated with early development of diabetic cataract.

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Knockdown of Archvillin by siRNA Inhibits Myofibril Assembly in Cultured Skeletal Myoblast

  • Lee, Yeong-Mi;Kim, Hyun-Suk;Choi, Jun-Hyuk;Choi, Jae-Kyoung;Joo, Young-Mi;Ahn, Seung-Ju;Min, Byung-In;Kim, Chong-Rak
    • Biomedical Science Letters
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    • v.13 no.4
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    • pp.251-261
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    • 2007
  • A myofiber of skeletal muscle is composed of myofibrils, sarcolemma (plasma membrane), and constameres, which anchor the myofibrils to the sarcolemma. Achvillin is a recently identified F-actin binding muscle protein, co-isolates with dystrophin and caveolin-3 in low-density sarcolemma of striated muscle, and colocalizes with dystrophin at costameres, the specialized adhesion sites in muscle. Archvillin also binds to nebulin and localizes at myofibrillar Z-discs, the lateral boundaries of the sarcomere in muscle. However other roles of archvillin on the dynamics of myofibrillogenesis remain to be defined. The goal of this study is, by using siRNA-mediated gene silencing technique, to investigate the effect of archvillin on the dynamics of myofibrillogenesis in cell culture of a mouse skeletal myogenic cell line (C2C12), where presumptive myoblasts withdraw from the cell cycle, fuse, undergo de novo myofibrillogenesis, and differentiate into mature myotubes. The roles of archvillin in the assembly and maintenance of myofibril and during the progression of myofibrillogenesis induced in skeletal myoblast following gene silencing in the cell culture were investigated. Fluorescence microscopy demonstrated that the distribution of archvillin was changed along the course of myofibril assembly with nebulin, vinculin and F-actin and then located at Z-lines with nebulin. Fluorescence microscopy demonstrated that knockdown of mouse archvillin expression led to an impaired assembly of new myofibrillar clusters and delayed fusion and myofibrillogenesis although the mouse archvillin siRNA did not affect those expressions of archvillin binding proteins, such as nebulin and F-actin. This result is corresponded with that of RT-PCR and western blots. When the perturbed archvillin was rescued by co-transfection with GFP or Red tagged human archvillin construct, the inhibited cell fusion and myotube formation was recovered. By using siRNA technique, archvillin was found to be involved in early stage of myofibrillogenesis. Therefore, the current data suggest the idea that archvillin plays critical roles on cell fusion and dynamic myofibril assembly.

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