• Corrosion Science and Technology
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• v.8 no.1
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• pp.1-10
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• 2009

The influence of Schiff bases on the corrosion inhibition of mild steel in 1 M $H_2SO_4$ have been investigated by weight loss, gasometry, impedance and polarization techniques. The results obtained reveal that these compounds act as good inhibitors. The inhibition efficiency of Schiff bases increased with concentration and synergistically increased on addition of chromate, sulphate and halide ions. Potentiodynamic polarization measurements clearly reveal that the investigated inhibitors are of mixed type but they are more cathodic in nature. The adsorption of these compounds on mild steel surface for both the acids were found to obey Langmuir adsorption isotherm. The surface morphology was studied by SEM and UV reflectance spectra.

• Journal of Industrial Convergence
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• v.21 no.10
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• pp.57-63
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• 2023

This study aims to elucidate the effect of glycyrrhizic acid on smooth muscle contraction and to determine the detailed mechanism incorporated. We hypothesized that glycyrrhizic acid played a role in the agonist-sensitive management of smooth muscle contraction. Stripped smooth muscles of Sprague-Dawley rats were prepared in organ baths and isometric tensions were converted, stored and analyzed by using isometric transducers, a physiograph and one way ANOVA. Interestingly, glycyrrhizic acid attenuated the thick filament regulating agonist (fluoride or thromboxane mimetic)-sensitive contraction (p=0.113, 0.008, 0.004 (Student's t-test), p=0.113, 0.008, 0.004 (One way ANOVA) at 0.01, 0.03, 0.1 mM fluoride, and p=0.156, 0.004, 0.003 (Student's t-test), p=0.156, 0.004, 0.003 (One way ANOVA) at 0.01, 0.03, 0.1 mM thromboxane mimetic) and did not attenuate the thin filament regulating agonist (phorbol ester)-induced contraction (p=0.392, 0.086, 0.065 (Student's t-test), p=0.392, 0.086, 0.065 (One way ANOVA) at 0.01, 0.03, 0.1 mM phorbol ester). It is suggesting that endothelial EDRF (NO) synthesis and accessory pathways besides endothelial EDRF (NO) synthesis such as ROCK restriction might be incorporated in the glycyrrhizic acid-induced modulation of smooth muscle contraction inhibiting acto-myosin interaction.

• Parasites, Hosts and Diseases
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• v.39 no.3
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• pp.241-246
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• 2001

The antigenic domain of the major surface protein (Nc-p43) of Neospora caninum was examined by polymerase chain reaction of its gene fragments and recombinant expression as GST fusion proteins. The fragments of Nc-p43 were as follow: a total open reading frame (OFR), T: OFR without signal sequence and C-terminal hydrophobic sequence, S: N-terminal 2/3 parts of S, A: C-terminal 2/3 parts, P; N-terminal 1/3 part, X: middle 1/3 part Y; and C-terminal 1/3 part, Z, respectively. The DNA fragments were cloned into pGEX-47 vector. Recombinant plasmids transformed into Escherichia coli of BL21 pLysS (DE3) strain were induced to express GST or GST fused fragments of Nc-p43 such as 69 kDa protein for T,66 kDa for S, 52 kDa for A,53 kDa for P, and 40 kDa proteins for X, Y, and Z, respectively in SDS-PAGE. The Nc-p43 fragments of T, S, and P reacted with a bovine serum of neosporosis while those of A, X, Y, and Z together with GST did not in the western blot. These findings suggest that the antigenic domain of Nc-p43 of N. caninum may be localized in the C-terminal 2/3 parts. Together with Al9 clone in SAGI of Toxoplasma gondii (Nam et at., 1996), the P fragment of Nc-p43 could be used as efficient antigens to diagnose and differentiate those infections with both species .

• Microbiology and Biotechnology Letters
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• v.36 no.1
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• pp.28-33
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• 2008

The expression vector (pWHM3-TR1R2) for sprT gene encoding Streptomyces griseus trypsin (SGT) followed by two regulatory genes, sgtR1 and sgtR2, was introduced into Streptomyces lividans TK24 and Streptomyces griseus IFO 13350. Various media with different compositions were used to maximize the productivity of SGT in the recombinant trains. he SGT productivity was best when the transformant of S. lividans TK24 was cultivated in R2YE medium (0.74 unit/mL) at 5 days of cultivation. C5/L (0.66 unit/mL) medium also gave a good productivity, but Livid (0.08 unit/mL) and NDSK (0.06 unit/mL) yielded poor productivities. S. griseus IFO 13350/pWHM3-TR1R2 produced SGT by 1.518 unit/mL (C5/L), 1.284unit/mL (R2YE),0.932 unit/mL (NDSK), and 0.295 unit/mL (Livid) at 7 days of cultivation, which was much higher than those from S. lividans TK24/TR1R2. The SGT protein was purified from the culture broth of S. griseus IFO 13350/pWHM3-TR1R2 in C5/L to homogeneity via ammonium sulfate fractionation, and CM-sepharose and SP-sepharose column chromatographies. The specific activity of purified SGT was 69,252 unit/mg, and the final purification fold and recovery yield were 6.5 and 1.4%, respectively.

• Journal of the Korean Mathematical Society
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• v.46 no.1
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• pp.99-111
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• 2009

A ring is called left P-coherent if every principal left ideal is finitely presented. Let M be a right R-module with the endomorphism ring S. We mainly study the P-coherence of S. It is shown that S is a left P-coherent ring if and only if the left annihilator $ann_S$(X) is a finitely generated left ideal of S for any M-cyclic submodule X of M if and only if every cyclically M-presented right R-module has an M-torsionfree preenvelope. As applications, we investigate when the endomorphism ring S is left PP or von Neumann regular.

• Applied Biological Chemistry
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• v.35 no.4
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• pp.227-231
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• 1992

The plasmids pSUPBT and pSUPBTR were constructed with a vector pSUP2021 and the BT toxin gene in the plasmid pES 1. The plasmids constructed were introduced into the antagonistic rhizobacteria P. fluorescens KR164 by conjugation and P. fluorescens having pSUPBT and pSUPBTR were named P. fluorescens KR164(pSUPBT)#2, KR164(pSUPBT)#3, KR164(pSUPBTR)#2 and KR164(pSUPBTR)#3, respectively. The BT toxin gene were identified in all transformants by Southern hybridization and the final product of BT toxin gene was identified only in P. fluorescens KR164(pSUPBTR)#3 by SDS-PAGE. This crystal toxin protein were also observed in electron microscopy.

• Restorative Dentistry and Endodontics
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• v.29 no.5
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• pp.470-478
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• 2004

The purpose of this study is to monitor the secretion of matrix metalloproteinase-1 (MMP-1) and tissue inhibitor of metalloproteinase-1 (TIMP-1) produced by human osteosarcoma cell line (MG63) stimulated with Prevotella nigrescens lipopolysaccharides (LPS). and to compare the level of secretion before and after the treatment of calcium hydroxide on P. nigrescens LPS. LPS was extracted and purified from anaerobically cultured P. nigrescens. MG63 cells were stimulated by the LPS (0, 1, $10{\;}\mu\textrm{g}/ml$) or LPS($10{\;}\mu\textrm{g}/ml$) pretreated with 12.5 mg/ml of $Ca(OH)_2$ for 3 days. Total RNA was isolated from the cell. and real-time quantitative polymerase chain reaction (PCR) was performed for quantification of MMP-1 and TIMP-1. The results were as follows. 1. MMP-1 mRNA expression at 48 hr was highly increased by stimulation with P. nigrescens LPS. The increase was dose-dependent. 2. When stimulated with ($1{\;}\mu\textrm{g}/ml$ of LPS. TIMP-1 mRNA expression was highly increased at 24 hr and 48 hr. However. TIMP-1 expression was suppressed at higher concentration ($10{\;}\mu\textrm{g}/ml$). 3. When P. nigrescens LPS was pretreated with $Ca(OH)_2$. MMP-1 and TIMP-1 gene expression was downregulated. The results of this study suggest that transcriptional regulation of MMP-1 and TIMP-1 by P. nigrescens LPS could be one of the important mechanisms in bone resorption of periapical inflammation. The result of calcium hydroxide on MMP-1 and TIMP-1 gene expression suppression shows that calcium hydroxide detoxified bacterial LPS and thus should be used the medication of choice for intracanal dressings in root canal infected with black-pigmented bacteria.

• Honam Mathematical Journal
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• v.35 no.4
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• pp.701-706
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• 2013

Summation theorems for hypergeometric series $_2F_1$ and generalized hypergeometric series $_pF_q$ play important roles in themselves and their diverse applications. Some summation theorems for $_2F_1$ and $_pF_q$ have been established in several or many ways. Here we give a proof of Watson's classical summation theorem for the series $_3F_2$(1) by following the same lines used by Rakha [7] except for the last step in which we applied an integral formula introduced by Choi et al. [3].

• Journal of Life Science
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• v.17 no.9 s.89
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• pp.1248-1254
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• 2007

The secretory overexpression of Clostridium thermocellum endoglucanase A gene (celA) was examined in Saccharomyces cerevisiae using Kluyveromyces marxianus exoinulinase (INU1) signal sequence and GAL10 promoter. The two plasmids, pYEG-CT1 with its own signal sequence, and pYInu-CT1 with INU1 signal sequence were introduced to S. cerevisiae SEY2102 and S. cerevisiae 2805 host strains, respectively, and then each transformant was selected on the synthetic defined media lacking uracil. The expression level and secretion efficiency of endoglucanase A was increased by $18{\sim}22%$ and 11%, respectively, by INU1 signal sequence over celA signal sequence. By considering the high level of expression (361 unit/I), plasmid stability (89%), and secretion efficiency (70%), S. cerevisiae 2805 harboring plasmid pYInu-CT1 was selected as the opti-mal host vector system for the production of cellulose-degrading enzyme and recombinant yeast probiotic. The total expression and secretion efficiency of endoglucanase A was 418 unit/l and 73%, respectively, in the batch fermentation of S. cerevisiae 2805/pYlnu-CT1 on galactose medium. The mo-lecular weight of secreted endoglucanase A was found to be greater than 100 kDa, presumably due to the N-linked glycosylation.

• Journal of the korean veterinary medical association
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• v.32 no.8
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• pp.535-539
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• 1996

국제양돈수의학회(International Pig Veterinary Society ; I.P.V.S) 제14차 총회 및 학술대회가 1996년 7월 7일부터 11일까지 이태리 중북부의 대학도시 볼로냐(Bologna, Italy)에서 개최되었다. I.P.V.S.는 1969년에 영국의 캠브리지 (Cambridge, United Kingdom)에서 창립된 이래 1996년 현재 53개 회원국 1,700 여명의 회원을 확보하고 있으며, 세계 각국의 양돈과 수의학에 관심을 가지고 있는 학자, 생산자 그리고 관련업계 인사들의 학술$\cdot$기술 정보교류와 협력을 목적으로 매 2년마다 세계 주요도시를 순회 하면서 개최되고 있다. 앞으로 2년후(1998년도)에는 I.P.V.S.의 탄생국인 영국의 버밍햄(Birmingham, United Kingdom)에서 제 15차 총회 및 학술대회를 개최할 예정이며 2000년대에는 시드니 올림픽과 때를 맞추어 호주의 멜보른(Melboume, Australia)에서 제16차 총회를 개최하기로 결정되어 있다. 금년(1996년도) I.P.V.S 총회에는 우리나라에서 30개 기관/업체로부터 50여명이 참여한 바 있으며 총 27편 (구두 9편, 포스터 18편)의 학술논문을 발표하는 등 눈부신 활약을 보인 바 있다. 금년도 I.P.V.S. 총회의 특징은 돼지의 전염성 질병중 근래에 우리나라에서도 문제시 되고 있는 '돼지 생식기 호흡기 중후군 (Porcine Reproductive and Respiratory Syndrome ; PRRS)'이 세계적인 관심의 대상이었으며, 이태리 양돈병리축산학회 (Societa Italiana di Patologia ed Allevamento dei Suini ; S.I.P.A.S) 주관으로 '돼지 적리 (Swine Dysentery)'에 관한 Satellite Symposium이 개최되었다는 점이다. WTO 이래 어려워지고만 있는 우리나라 축산업 분야중 그래도 비젼이 보이는 양돈산업과 관련하여, I.P.V.S.를 통하여 우리나라 수의업무의 세계화의 길을 찾아보고자, 1 국제양돈수의학회(I.P.V.S)의 역사 (양돈과 수의업무 전문가의 새로운 만남의 장), 2 I.P.V.S.에의 참여(제13차 방콕대회), 3 한국 수의사의 활약(제14차 볼로냐대회), 4 세계화의 길(제15차 버밍햄대회, 제16차 멜보른대회), 5 국내양돈의 문제와 우리가 해야할 일(수의업무 세계화의 길을 찾자)등의 순으로 적어보고자 한다.