• Journal of Microbiology
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• v.39 no.3
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• pp.168-176
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• 2001

Five different types of catalases from photosynthetic bacterium Rhodospirillum rubrum S1 grown aerobically in the dark were found in this study, and designated Catl (350 kDa), Cat2 (323 kDa), Cat3 (266 kDa), Cat4 (246 kDa), and Cat5 (238 kDa). Analysis of native PAGE revealed that Cat2, Cat3, and Cat4 were also produced in the cells anaerobically grown in the light. It is notable that only Cat2 was expressed much more strongly in response to the anaerobic condition. Enzyme activity staining demonstrated that Cat3 and Cat4 had bifunctional catalase-peroxidase activities, while Catl, Cat2, and Cat5 were typical monofunctional catalases. S1 cells grown aerobically in the presence of malate as the sole source of carbon exhibited an apparent catalase Km value of 10 mM and a Vmax of about 705 U/mg protein at late stationary growth phase. The catalase activity of Sl cells grown in the anaerobic environment exhibited a much lower Vmax of about 109 U/mg protein at late logarithmic growth phase. The catalytic activity was stable in the broad range of temperatures (30$\^{C}$-60$\^{C}$), and pH (6.0-10.0). R. rubrum S1 was much more resistant to H$_2$O$_2$in the stationary growth phase than in the exponential growth phase regardless of growth conditions. Cells of stationary growth phase treated with 15 mM H$_2$O$_2$for 1 h showed 3-fold higher catalase activities than the untreated cells. In addition, L-glutamate induced an 80-fold increase in total catalase activity of R. rubrum S1 compared with magic acid. Through fraction analyses of S1 cells, Cat2, Cat3, Cat4 and Cat5 were found in both cytoplasm and periplasm, while Catl was localized only in the cytoplasm.

• Journal of Periodontal and Implant Science
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• v.25 no.2
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• pp.222-238
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• 1995

Inflammatory cells may produce active species of oxygen in antimicrobial defense. While such species can directly damage surrounding tissue, their major secondary role may be to mediate important components of the inflammatory response. Superoxide dismutase, antioxidant, have significant anti-inflammatory properties in rheumatoid arthritis, ischemic tissue injury and gastrointestinal disease. Increased oxidative product formation diseases. And superoxide dismutase produced by Porphyromonas Gingivalis is resistant to killing by polymorphonuclear leukocyte. The purpose of this study was to investigate on the effects of superoxide dismutase in 3T3 fibroblast and in experimental gingivitis in the rats. The effect of superoxide dismutase(SOD) to cell morphology and cell activity was measured in cultured mouse 3T3 fibroblast. After experimental gingivitis were induced by lipopolysaccharide(LPb) and bovine serum albumin(BSA), injection of SOD were done. WBC count and histologic findings were observed at 1, 2, 3, and 7 days. The results were as follows; 1. There was a little difference between LPS treated groups and SOD treated groups in 3T3 fibroblast morpholoy. 2. There was no difference between only SOD treated groups (except SOD 150U at 3days) and control in 3T3 fibroblast activity. 3. LPS $0.5{\mu}g/ml$ and SOD treated groups (except 150U) had decreased 3T3 fibroblast activity and no significant difference at 3 days. 4. LPS $5.0{\mu}g/ml$ and SOD treated groups were significantly increased cell activity of 3T3 fibroblast than control group at 1 day(P<0.05). 5. In LPS induced gingivitis, the number of leukocytes in SOD treated was significantly decreased than in saline treated at 1 day(P<0.05). 6. In histopathologic findings of LPS or BSA induced gingivitis, inflammatorycell infiltration in SOD treated groups were less than in saline treated group at 1, 2 and 3 days.

• Journal of Korean Academy of Nursing
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• v.22 no.2
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• pp.238-247
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• 1992

Immigration of Koreans to the United States has increased since the 1960's. Adjusting to life in the United States produces a great deal of stress for immigrants. Despite better economic opportunites, many see the U.S. culture as threatening to their family and cultural values. Differences in culture, language, expectations and social behavior can lead to misunderstandings between health care providers and clients. These misunderstanding can leaf to frustration on the part of each. The ultimate result of this is that often Korean-immigrants do not get their health care needs met and stress response symptoms can lead to disease if there is no appropriate care. To determine the health care needs and concerns of Korean-Americans, a health needs assessment is needed. Appropriate and adequate information about the health care needs of these individuals is important as it relates to American policy changes allowing greater numbers of immigrants to enter the U.S. The purpose of this prospective study was to describe Korean-American stress response. This study focused on the primary presenting problems for which subjects reported having sought care. These included a variety of stress-related symptoms, including peripheral manifestations, cardiopulmonary symptoms, central-neurological symptoms, gastrointestinal symptoms, muscle tension, habitual patterns, depression, anxiety, emotional irritability and cognitive disorganization. Of the 300 subjects who entered the study, 80% (N＝223) completed the questionnaire in full. Demographically, the percentage of females and males was 50% each and they ranged in age from 20 to 69 years. Ninety percent of the subjects were highly educated, 25% owners of business, 25% white collar professionals, 15% employed in sales or as skilled /unskilled labor, 30% had no occupation : and 5% were housewives or students. The SOS inventory is designed to quantify self-perception of behavioral, cognitive, and physiological components of the stress response. It consisted of 94 items divided into 10 subscales. The result of this study are as follows : The total mean 505 of all subjects (N＝223 was .8129 ; the mean 505 for male(N＝114) was .7665 and for females, (N＝108) .8594. The level of symptoms for central-neurologic and muscle tension was higher for than for males. The highest stress response of all subjects was emotional irritability symptoms(1.0644) : the lowest stress response of all subjects was peripheral manifestation symptoms.

• Journal of Digital Convergence
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• v.15 no.7
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• pp.231-238
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• 2017

The purposes of this study is to analysis the differences of the hospital choice factors between first-visit and revisit patients in general hospitals. The samples used for data analysis are 499 outpatients of G, H, S, U hospitals using a standardized questionnaires in 4 provinces. In case of first-visit patients, human, effectiveness and accessibility factors were found to have a significant positive(+) effect on hospital choice factors. In case of revisit patients, human, physical, accessibility, image of hospital and salary factors were found to have a significant positive(+) effect on hospital choice factors. Based on these results, this study suggests implications to improve customer satisfaction, profitability and provide a high-quality medical service by making effectively use of planning strategies of hospital management with a variety of factors.

• Nuclear Engineering and Technology
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• v.52 no.12
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• pp.2725-2732
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• 2020

This paper presents the neutronics benchmark analysis of the first core of the Indonesian multipurpose research reactor RSG-GAS (Reaktor Serba Guna G.A. Siwabessy) calculated by the Serpent Monte Carlo code and the newly released ENDF/B-VIII.0 nuclear data library. RSG-GAS is a 30 MWth pool-type material testing research reactor loaded with plate-type low-enriched uranium fuel using light water as a coolant and moderator and beryllium as a reflector. Two groups of critical benchmark problems are derived on the basis of the criticality and control rod calibration experiments of the first core of RSG-GAS. The calculated results, such as the neutron effective multiplication factor (k) value and the control rod worth are compared with the experimental data. Moreover, additional calculated results, including the neutron spectra in the core, fission rate distribution, burnup calculation, sensitivity coefficients, and kinetics parameters of the first core will be compared with the previous nuclear data libraries (interlibrary comparison) such as ENDF/B-VII.1 and JENDL-4.0. The C/E values of ENDF/B-VIII.0 tend to be slightly higher compared with other nuclear data libraries. Furthermore, the neutron reaction cross-sections of ¹⁶O, ⁹Be, ²³⁵U, ²³⁸U, and S(𝛼,𝛽) of ¹H in H₂O from ENDF/B-VIII.0 have substantial updates; hence, the k sensitivities against these cross-section changes are relatively higher than other isotopes in RSG-GAS. Other important neutronics parameters such as kinetics parameters, control rod worth, and fission rate distribution are similar and consistent among the nuclear data libraries.

• Nuclear Engineering and Technology
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• v.54 no.11
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• pp.4253-4264
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• 2022

Since the implementation of the phosphate project in Bled El-Hadba (BEH) deposit, western region of Tébessa, no detailed study has been conducted to assess the natural radioactivity distribution and the associated radiological risk parameter for this open-pit mine. For the sake of determining a credible premining reference database for the region of interest, 21 samples were collected from different geological layers of the above-mentioned deposit. Gamma Spectrometry was applied for measuring radioactivity using a high resolution HPGe semiconductor detector. The obtained activity results have shown a significant broad variation in the radioactive contents for the different phosphate samples. The total average concentrations (in Bq·kg^-1) for ²²⁶Ra, ²³⁸U, ²³⁵U, ²³²Th and ⁴⁰K computed for the different type of phosphate layers were found to be 570 ± 169, 788 ± 280, 52 ± 18, 66 ± 6 and 81 ± 18 respectively. The mean activity concentrations of the measured radionuclides were compared to other regional and worldwide deposits. The ratios between the detected radioisotopes have been calculated for spatial distribution of natural radionuclides in the study area. Based on the aforementioned activity concentrations, the corresponding radiation hazard parameters were assessed. Correlations between the obtained parameters were drawn and a multivariate statistical analysis (Pearson Correlation, Cluster and Factor analysis) was carried out in order to identify the existing relationships.

• Journal of Radiation Protection and Research
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• v.39 no.1
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• pp.54-60
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• 2014

IAEA has employed various types of radiation detectors - HPGe, NaI, CZT - for accountancy of nuclear material. Among them, HPGe has been mainly used in verification activities required for high accuracy. Due to its essential cooling component(a liquid-nitrogen cooling or a mechanical cooling system), it is large and heavy and needs long cooling time before use. New hand-held portable HPGe has been developed to address such problems. This paper deals with results of performance evaluation test of the new hand-held portable HPGe prototype which was used during IAEA's inspection activities. Radioactive spectra obtained with the new portable HPGe showed different characteristics depending on types and enrichments of nuclear materials inspected. Also, Gamma-rays from daughter radioisotopes in the decay series of $^{235}U$ and $^{238}U$ and characteristic x-rays from uranium were able to be remarkably separated from other peaks in the spectra. A relative error of enrichment measured by the new portable HPGe was in the range of 9 to 27%. The enrichment measurement results didn't meet partially requirement of IAEA because of a small size of a radiation sensing material. This problem might be solved through a further study. This paper discusses how to determine enrichment of nuclear material as well as how to apply the new hand-held portable HPGe to safeguard inspection. There have been few papers to deal with IAEA inspection activity in Korea to verify accountancy of nuclear material in national nuclear facilities. This paper would contribute to analyzing results of safeguards inspection. Also, it is expected that things discussed about further improvement of a radiation detector would make contribution to development of a radiation detector in the related field.

• Journal of Microbiology and Biotechnology
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• v.21 no.10
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• pp.1012-1020
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• 2011

A gene coding for an endoglucanase (EglA), of the glycosyl hydrolase family 12 and derived from Aspergillus niger VTCC-F021, was cloned and sequenced. The cDNA sequence, 717 bp, and its putative endoglucanase, a 238 aa protein with a predicted molecular mass of 26 kDa and a pI of 4.35, exhibited 98.3-98.7% and 98.3-98.6% identities, respectively, with cDNA sequences and their corresponding endoglucanases from Aspergillus niger strains from the GenBank. The cDNA was overexpressed in Pichia pastoris GS115 under the control of an AOX1 promoter with a level of 1.59 U/ml culture supernatant, after 72 h of growth in a YP medium induced with 1% (v/v) of methanol. The molecular mass of the purified EglA, determined by SDS-PAGE, was 33 kDa, with a specific activity of 100.16 and 19.91 U/mg toward 1% (w/v) of ${\beta}$-glucan and CMC, respectively. Optimal enzymatic activity was noted at a temperature of $55^{\circ}C$ and a pH of 5. The recombinant EglA (rEglA) was stable over a temperature range of $30-37^{\circ}C$ and at pH range of 3.5-4.5. Metal ions, detergents, and solvents tested indicated a slightly inhibitory effect on rEglA activity. Kinetic constants ($K_m$, $V_{max}$, $k_{cat}$, and $k_{cat}/K_m$) determined for rEglA with ${\beta}$-glucan as a substrate were 4.04 mg/ml, 102.04 U/mg, 2,040.82 $min^{-1}$, and 505.05, whereas they were 10.17 mg/ml, 28.99 U/mg, 571.71 $min^{-1}$, and 57.01 with CMC as a substrate, respectively. The results thus indicate that the rEglA obtained in this study is highly specific toward ${\beta}$-glucan. The biochemical properties of rEglA make it highly valuable for downstream biotechnological applications, including potential use as a feed enzyme.

• Korean Journal of Microbiology
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• v.30 no.3
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• pp.232-238
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• 1992

Canz~~j~lohuc;tc.~jurn i werc studied for their heat shock responses at several elevated temperatures and their heat shock genes were detected by the technique of Southern hybridization. (.. ,jc\ulcorneruni sy~>thesized the major heat shock proteins of hsp90. hsphh. and hsphO at 48$^{\circ}$C . ant1 their w~u.ival rates were maintained as the same level at optimal temperature. '1-hc heat shock genes in chromosome of C ,jc:jutii werc determined to be homologous to the heat shock genes or E. t,oli. by showing strong signals in Southern hybridization analysis using clnaK and groESL- as DNA probe But the restriction sites for thc fragmcnts including heat shock genes were different betueen E. c,oli and C ,jtjuni.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.15
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• pp.211-238
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• 2001

This article discusses and analyses several issues regarding to the Electronic Signature and the Electronic Certification. The objects of the analyse are the each paragraphs of the Korean Electronic Signature Act of 1999 and that of the Korean Electronic Transaction Basic Act of 1999 in comparing to the paragraphs of the Electronic Signatures in Global and National Commerce Act' (E-Sign) of 2000, U.S.A. and that of the Draft UNCITRAL Model Law on Electronic Signature of 2000. The main issues discussed herein are the scope of the electronic signature, the definition of the electronic signature, permission of services to the non-authorized certification service providers, the effect of the electronic signature, the liability of the concerning parties of the electronic signature including liability of the certification service providers, that of the subscribers and that of the relying parties. This paper also discusses the problems of the possibility of issuing the electronic negotiable commercial papers, the validity of the electronic signatures done by electronic agents, the authority certificate, mutual certification of the foreign certification service providers, the permission of the electronic notary service, the problems of the consumer protection and the possibility of issuing electronic insurance policy, etc. The writer concludes by suggesting some measures that will activate the use of electronic signatures under the korean circumstances.