• Korean Chemical Engineering Research
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• v.43 no.2
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• pp.202-205
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• 2005

The effects of ligands on reactivity under GoAgg oxidation system have been studied. Picolinic acid containing carboxylic acid showed the most excellent activity among various ligands. Also, Picolinic acid of ortho position carboxylic group in pyridine ring largely increased reaction rates in the GoAgg oxidation systems. From these results, we proposed the new mechanism on the GoAgg oxidation using ligands having carboxylic group at ortho position.

• Journal of Genetic Medicine
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• v.13 no.1
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• pp.14-19
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• 2016

Purpose: We examined the prevalence and CGG/AGG repeat structure of expanded alleles of the FMR1 gene in preconceptional and pregnant Korean women. Materials and Methods: The CGG repeats in the FMR1 genes of 1,408 women were analyzed by polymerase chain reaction and Southern blot analysis. To estimate the prevalence of expansion alleles, the individuals were divided into low risk and high risk group. Results: Within this population, 98.4% had normal alleles and 1.6% had abnormal alleles including intermediate (0.6%), premutation (0.5%), full mutation (0.1%), and hemizygous (0.4%) alleles. There were 2 premutation alleles (1:666, 95% confidence interval [CI] 1:250-1,776) in the low risk group and 5 premutation alleles (1:15, 95% 1:6-36) in the high risk group. There were 8 intermediate alleles (1:167, 95% CI 1:130-213) in the low risk group and 1 intermediate alleles (1:76, 95% CI 1:11-533) in the high group. Six of the 7 premutation alleles did not contain AGG interruptions within the repeats and 1 had a single AGG interruption. Four of the 9 intermediate alleles contained 2-3 AGG, 4 had a single AGG, and 1 had no AGG interruptions. Conclusion: Our study demonstrates the prevalence and CGG/AGG structure of expansion alleles in Korean women. The identified premutation prevalence is higher than that of other Asian populations and lower than that of Caucasian populations. Although our study is limited by size and population bias, our findings could prove useful for genetic counseling of preconceptional or pregnant women.

• Journal of Microbiology and Biotechnology
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• v.28 no.4
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• pp.566-570
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• 2018

Because glycosylation of aesculetin and its 6-glucoside, aesculin, enhances their biological activities and physicochemical properties, whole-cell biotransformation and enzymatic synthesis methodologies using Neisseria polysaccharea amylosucrase were compared to determine the optimal production method for glycoside derivatives. High-performance liquid chromatography analysis of reaction products revealed two glycosylated products (AGG1 and AGG2) when aesculin was used as an acceptor, and three products (AG1, AG2, and AG3) when using aesculetin. The whole-cell biotransformation production yields of the major transfer products for each acceptor (AGG1 and AG1) were 85% and 25%, respectively, compared with 68% and 14% for enzymatic synthesis. These results indicate that whole-cell biotransformation is more efficient than enzymatic synthesis for the production of glycoside derivatives.

• Development and Reproduction
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• v.17 no.4
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• pp.409-420
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• 2013

Human serum (HS) has been reported to induce aggregation of human eyelid adipose-derived stem cells (HEACs) during high-density culture in vitro. The present study focused on the role of cell adhesion molecules and gelatinases during HS-induced aggregation of HEACs. HS-induced aggregation occurred between 9-15 days of culture. Cells aggregated by HS medium (HS-agg) showed stronger expression of ${\alpha}2$, ${\alpha}2B$, ${\alpha}X$, and CEACAM1 genes compared to non-aggregated cells in HS medium (HS-ex) or in control FBS-cultured cells. HS-agg were distinctly labeled with antibodies against ${\alpha}2$, ${\alpha}2B$, and ${\alpha}X$ proteins. Western blot results demonstrated that the two integrin proteins were greatly expressed in HS-agg compared to HS-ex and control FBS-cultured cells. Treatment of HEACs with anti-integrin ${\alpha}2$ antibody during culture in HS medium delayed aggregation formation. HS-agg exhibited strong expression of MMP1 and MMP9 compared to HS-ex or FBS-cultured cells. Conditioned media from HS-culture showed remarkable increase of MMP9 gelatinolytic activity in comparison to those from FBS-culture. However, there was no change of TIMP mRNA expression in relation to the HS-induced aggregation. Based on these results, it is suggested that integrin ${\alpha}2$, ${\alpha}2B$, and ${\alpha}X$, and MMP9 might play an important role in the HS-induced aggregation of HEACs.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.41 no.2
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• pp.31-40
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• 2004

Diff-Serv(DS) is a mechanism by which network service providers can offer differing levels of network service to different traffic, in so providing quality of service(QoS) to their customers. Because this mechanism has been deployed just for fixed hosts with the Token Bucket mechanism according to AggF(Aggregate Flow) instead of each flow, DS can not suggest effective usability of traffic resources. In this paper, we use WFQ mechanism for traffic conditioner and scheduling method monitoring the AggF and the results will be used to control the next flows coming in TC. So it will control traffic rate dynamically and suggest efficient usability of bandwidth.

• Korean Journal of Microbiology
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• v.44 no.3
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• pp.221-227
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• 2008

Bordetella pertussis is pathogenic bacteria causing pertussis, a infectious respiratory disease for the infants. The incidence rate of pertussis was significantly decreased after introduction of vaccine. However, increased pertussis cases are recently reported in several countries with high vaccine coverage. One of the inferred reasons is genotype or serotype variation between circulating strains and vaccine strains. Therefore, it is required to confirm the variation status of the isolates by genotype or serotype analysis and the possibility of pertussis outbreak in Korea should be estimated. For this, the serotype variations of the isolates from $1999\sim2006$ were investigated in agglutinogen and fimbriae. As the result, the most frequent serotype in the isolated strains was agglutinogen 1 and fimbriae 2 serotypes. Moreover, serotype transition from vaccine serotypes to non-vaccine serotypes was observed. Especially, the transition pattern of agglutinogen serotype was directed to increase a different type (agg 1) from the vaccine type (agg 1,2). However, in case of fimbriae, the same type (fim 2) with vaccine strain was increased. These results were also observed in other countries with increasing incidence of pertussis. For more predictable results to know increasing possibility of pertussis incidence in Korea, the studies on genetic variations of antigenic determinant genes and prevalence of antibody titer in normal population should be performed in the further.

• Bulletin of the Korean Chemical Society
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• v.21 no.3
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• pp.353-354
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• 2000

• Biotechnology and Bioprocess Engineering:BBE
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• v.5 no.2
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• pp.79-83
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• 2000

A han transfers her serum immunoglobulin G to the agg (IgY) and gives immunity to her offspring. Therefore, The hen agg can be an effective supplier of a large amount of antigen specific antibody that accumulates in the egg yolk. Antigen specific antibody has been widely used for immunological analysis in the field of diagnosis as well as pure scientific research. The production and separation technology of IgY is demonstrated in the present study.

• Journal of the Korean Society for Heat Treatment
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• v.35 no.2
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• pp.74-81
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• 2022

This study aims to mitigate the microstructural heterogeneity arising from the manufacture of magnesium alloy plates using the twin roll casting (TRC) process. Homogenization was introduced through hot rolling and heat treatment, followed by confirmation of observed changes in the microstructure. Following the TRC process, the hot rolled 2mm plate exhibited a dendritic cast structure tilted in the roll rotation direction, while central segregation were developed. This nonuniform structure and central segregation disappeared upon heat treatment, followed by recrystallization to form uniform and fine grains. Abnormal grain growth (AGG) was observed over the course of heat treatment; grains exhibiting AGG occupied up to 75% of the total area after having held the sample at 400℃ for 64 h. The formation of coarse grains was also observed during heat treatment at 340℃ over a relatively long duration, though the maximum grain size was significantly smaller than that corresponding to the heat treatment at 400℃. AGG in the 400℃ heat treatment occurred because of movement of the grain boundary, which had been fixed prior as a result of the grain boundary fixing effect of the precipitation phase. The re-dissolution of the Ca₂Mg₅Zn₅ precipitated phase over the long duration of the high-temperature annealing process caused the surrounding grains to disappear and regrow.

• Food Science of Animal Resources
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• v.30 no.1
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• pp.148-153
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• 2010

The aim of this study was to investigate the virulence factor profiles of Escherichia coli strains isolated from pork and chicken meats purchased from retail markets in Korea. From 943 pork and 142 chicken meats, 217 isolates of E. coli were cultured. The presence of 11 virulence factors (elt, estI, estII, astA, stx, cdt, cnf, agg, inve, eae, afa) were detected by polymerase chain reaction. Forty one (18.9%) of 217 E. coli isolates carried at least one virulence factor. Among 175 E. coli isolates from pork, the detection rate of astA, elt, eae, estII, estI, afa, and cnf were 6.9%, 4.6%, 4.6%, 4.0%, 2.3%, 1.1%, and 0.6%, respectively. However, stx, agg, and cdt were not detected in our isolates. Therefore, we conclude that astA is the most prevalent virulence factor in E. coli isolates contaminated in pork and chicken meats in Korea.