• Research in Plant Disease
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• v.12 no.3
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• pp.272-277
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• 2006

Recycled irrigation water is a primary inoculum source of Phytophthora spp. and is capable of spreading propagules throughout nursery cultivation. Ozonation is commonly used to disinfest the recycled irrigation water; however, ozone has not been fully researched as a disinfectant for this purpose. In this study, zoospores of four species of Phytophthora were exposed for $1{\sim}9$ min to free available ozone at $0.1{\sim}0.3,\;0.5{\sim}0.7,\;0.9{\sim}1.2,\;1.4{\sim}1.7\;and\;1.9{\sim}2.2mg/l$. Zoospores, mycelial fragments, and culture plugs of P. nicotianae also were exposed to ozone concentrations ranging from 0.1 to 2.2 mg/l for periods ranging from 1 to 9 min. In addition, ozonated water was assayed monthly in 2004 and 2005 at two commercial nurseries, and quarterly in the first year at two other nurseries in Suwon, for ozone and survival of pythiaceous species using a selective medium. No zoospores of any species tested survived endpoint free ozone at 1.4 mg/l while limited mycelial fragments of P. nicotianae survived at 1.9 mg/l, and mycelial plugs treated at the same level of ozone were able to produce few sporangia. Phytophthora spp. were recovered only from nursery irrigation water with levels of free ozone at 0.3 mg/l or lower. The results of this study are essential for improving current ozonation sterilization.

• Journal of the Korean Society of Radiology
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• v.5 no.2
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• pp.51-58
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• 2011

This research compared and analyzed the heart rate of the patient in which the LVEF value is 40% less than and normal patient. When as for LVEF 40% or less becomes to each heart rate and LVEF in a relation, we can know that the time to reach 100HU hangs long. Therefore, in patients, that is 40% less than, when setting up the Premonitoring delay, we could know to could give 5 primary solid phrases. It is seen that subsequently an addition injected 40cc as to Saline, to all patients by 4cc/sec speeds after injecting the capacity of Scan time ${\times}$ 4cc + 30cc with 4cc/sec speeds. And HR excludes 80 or greater in 40% less than, the contrast agent shows the large-scale difference. In addition, in 40% less than, it could predict that the time difference was big and the contrast agent was already out in the Left ventricle Wash- when the contrast agent reached 100HU and Scan was started There is a wide difference between under 40% LVEF and normal. when starting scan from low LVEF patients. So, Injection contrast media protocol Should be determined to CCTA. And then In case of low LVEF is recommended to more low Pitch than routine Pitch because we should reduce scan failed in accordance with low LVEF.

• The Journal of Korean Society of Virology
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• v.27 no.2
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• pp.161-168
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• 1997

The present study was designed to estimate the seroprevalence of NLVs among diarrheagenic children and in healthy adults in Seoul and its vicinity with the use of an EIA and an Western blot (WB) based on recombinant Norwalk virus capsid protein (rNV) and crude virus preparations as antigen. Seroconversion was observed in 34 (83%) of 41 tested using the EIA and in 21 (54%) of 39 using the WB, suggesting that the NLVs with epitopes common to rNV are prevalent in Seoul area. Diarrheal children who were known to have been infected with several other strains of the NLVs showed no significant antibody response to the rNV. Infection with rNV occurred earlier in life: primary infections with rNV were common before the age of 6 months and over 91 % of children had evidence of infection by that age by the EIA. Since the amount of the NLV antigens available for seroepidemiologic surveys is limited, we tried to detect NLV antibody by using crude virus preparations as antigen. One crude virus preparation of a child whose stool yielded genetically distinct NLV revealed the presence of the plural number of bands upon SDS-PAGE, but precipitated only one band (62 kDa) after the WB with a serum (collected 10 days after the onset of symptoms) of another diarrheal child. The WB assay we present in this report revealed that the NLVs are prevalent among Korean population and that the sera contained antibody to a single major structural protein, with molecular sizes of 58 to 62 kDa, compatible with the sizes reported for the Norwalk virus and Snow Mountain agent proteins, respectively. When the results of the WB were compared with those obtained by the EIA, the EIA antibody assay was sensitive enough to detect an antibody rise of as much as 4096-fold but not as specific as the WB. The WB assay presented in this paper will provide a powerful tool to elucidate not only antigenic structures of the NL Vs but also seroepidemiology of the NLV infection. The availability of an unlimited source of antigen will enable a large scale serologic studies that will greatly increase our understanding of the role of NLVs in human enteric illness.

• Korean Journal of Social Welfare
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• v.37
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• pp.171-193
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• 1999

The ultimate goal of rehabilitation is social integration. Reemployment is, for the disabled workers, the primary source of not only income, but also identity and interaction. Unfortunately, for most disabled workers employment represents only a yet-to-be-fulfilled hope, a close but inaccessible goal, a daily reminder that they are not among the majority. The purpose of this study is to estimate reemployment rate in the industrial injured and to find factors affecting reemployment of disabled workers owing to industrial injury, and to make policy implication for the better industrial injury compensation rehabilitation system. The data were obtained through telephone interview with disabled worker who completed work injury compensation process in 1996-1997. The final sample was consisted of 1,060 respondents. The major findings were that almost lout of 3 disabled worker returned to work, and that the factor affecting reemployment of the disabled workers were severity injury, ADL(activity of Daily Living), the perception of disability severity, controlling for the demographic factors such as sex, age, education, marital status. The results indicated that psychosocial factors as well as physical function had influces on returning to work. The current findings suggests that rehabilitation services and policy aimed at enhancing vocational rehabilitation program and rehabilitation engineering services, and improving psychosocial resources should be considered by rehabilitation professionals and policy makers.

• Korean journal of communication and information
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• v.16
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• pp.168-206
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• 2001

This study attempts to examine the relationships between the major market-based media and the government after closing military regime era, 1961-1987. After the military regime was collapsed, while the mass media in Korea obtained independence and autonomy from government, they have been confronted with the terrible competition not so much comparatively as before. The watchdog role in the traditional liberalism, which is regarded as normative relationship between the media and the government would be transformed in accordance with the market condition and the maturity of democracy. Thus, the watchdog metaphor has been variously deviated in rower-centered society; lap dog, guard dog, attack dog. liberalists argue that the primary democratic role of the media is to art as a public watchdog overseeing the state. Social democrats, however, criticize them as simplistic conception which could be only applied to the government. They argue that the media should be seen as a source of redress against the abuse of all forms of power over others; the home, the economy, and the civil society. The lap dog view is that the media is overwhelmingly dependent on the established power structure contrary to the watchdog. While the guard dog perspective is a means to preserve the power structure alarming with playing 'conflict role', the attack do8 aims to the private interest of the media in intruding into the politics. The attack dog perspective by T. Patterson could be composed of the interpretive style of report, the game schema report over the policy schema in the election, and the negativism against politics and government. The market-dominant press has been likely to transform from lap-guard dog into attack-guard dog. In Roh Tae Woo government(1988-1992), while the press was a lessened lap-guard dog before three parties merger in 1990, after merger the press had been transformed as the reinforced lap-guard dog because this merger entailed joint, party-to-party negotiations, and the formation of the new party preceded by dissolution of the ruling blot. In the early stage of Kim Young Sam government(1993-1997), the press has kept in pace with the reform movement drive-forced by the government. However, the press withdrew the support of Kim's reform in reaching the level of threat to ruling bloc. The press coalesced only circumstantially with government and was interested in preserving some margin of independence. The failure of Kim's reform proved the political muscle of the press in post-autho-ritarianism. In the middle stage of Kim Dae Jung government (1998-) that resulted in the shift of power structure as once-opposition party leader, the stress has been a manifested attack-guard dog owing to the anti-cold war policy, the realignment policy of power, and the minority-base of Kim's government. The press has endeavored to hold political communication within limits relatively less threatening to the established order.

• Journal of Environmental Health Sciences
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• v.41 no.3
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• pp.182-190
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• 2015

Objectives: To introduce a protocol of Mobi-kids study which was aimed to examine an association between radiofrequency (RF) radiation exposure by mobile phone use and brain tumor risk in children and adolescents. Methods: The Mobi-kids study was a multinational matched case control study using a standardized protocol with the number of subjects targeted about 1,000 cases and 2,000 controls aged 10 to 24. In Mobi-Kids Korea, the source population was restricted to Seoul, Incheon, and Gyeonggi-do province. Eligible cases of primary brain tumor (glioma, meningioma, and others) were diagnosed from January 2012 to June 2015. Eligible controls were appendicitis patients operated during the study period. Two controls were matched on age, gender, and study region for 1 case. Information about pattern and history of mobile phone use and other covariates were obtained by face to face interview by trained interviewer. The Mobi-kids study has been involved in Mobi-expo as a validation study about mobile phone use, XGridmaster to localize tumor in the brain for RF energy calculation, and histological review for validation of diagnosis. Results: The Mobi-kids was the first and largest study in children and adolescents to estimate risk of brain tumor in association with the RF energy absorption in the brain estimated by mobile phone use. Forty-six-cases and 54 controls were collected as of September 2014 in Korea. Conclusions: The meaningful results of the study were expected because of the largest sample size, high validity of EMF exposure assessment as well as the susceptible study populationof children and adolescents.

• Journal of the Korean Applied Science and Technology
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• v.32 no.1
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• pp.93-99
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• 2015

The aim of this study was to analyze nutritional compositions of rapeseed pollen granules and to determine the possible usage of pollen granules as a yeast culture medium. Rapeseed pollen granules (per 100 g) were consisted of carbohydrate 58.9 g, protein 20.8 g, fat 4.1 g, ash 2.5 g and water 13.7 g. And fructose (13.7 g), glucose (11.1 g), and sucrose (6.6 g) of sugars and K (606.7 mg) and P (603.3 mg) of minerals were highly contained. In addition, free amino acids such as glutamic acid (2,482.4 mg), aspartic acid (2,136.5 mg), lysine (1,648.3 mg), and leucine (1,631.1 mg) were present at a higher level. When liquid medium, which was made from cracked pollen granules (5, 10, 15, 20, 25, 30, and 40 g/L), was tested for yeast culture, liquid medium containing pollen granules over 15 g/L showed higher yeast growth than YPD medium (control). Liquid medium containing both cracked pollen granules (15 g/L) and NaCl (1 ~ 20 g/L) improved yeast growth than the liquid medium without NaCl. In addition, when yeast growth was tested on solid medium made from pollen granules (15 g/L) at $30^{\circ}C$ for 2 days, yeast colonies were equally well-formed like those grown on YPD medium. Overall, rapeseed pollen granules have potential properties on yeast growth and could be used as a primary source for yeast culture.

• Ocean and Polar Research
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• v.29 no.2
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• pp.87-99
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• 2007

This study was conducted to understand the source and behavior of organic matter using the fluorescent technique (excitation-emission matrix) as a part of environmental monitoring program in the Korea manganese nodule mining site in the Northeastern Pacific Ocean. Water samples were collected at $0^{\circ},\;6^{\circ}N$, and $10.5^{\circ}N$ along $131.5^{\circ}W$ in August 2005. The concentration of total organic carbon (TOC) ranged from 58.01 to $171.93\;{\mu}M-C$. The vertical distribution of TOC was characterized as higher in the surface layer and decreased with depth. At $6^{\circ}N$, depth-integrated (from surface to 200 m depth) TOC was $337.1\;gC/m^2$, which was 1.4 times higher value than other stations. The exponential decay curve fit of vertical profile of TOC indicated that 59% of organic carbon produced by primary production in the surface layer could be decomposed by bacteria in the water column. Dissolved organic matter is generally classified into two distinctive groups based on their fluorescence characteristics using three-dimensional excitation/emission (Ex/Em) fluorescence mapping technique. One is known as biomacromolecule (BM; protein-like substance; showing max. at Ex 280/Em 330), mainly originated from biological metabolism. The other is geomacromolecule (GM; humic-like substance; showing max. at Ex 330/Em 430), mainly originated from microbial degradation processes. The concentration of BM and GM was from 0.42 to 7.29 TU (tryptophan unit) and from 0.06 to 1.81 QSU (quinine sulfate unit), respectively. The vertical distribution of BM was similar to that of TOC as high in the surface and decreased with depth. However, the vertical distribution of GM showed the reverse pattern of that of BM. From these results, it appeared that BM occupied a major part of TOC and was rapidly consumed by bacteria in the surface layer. GM was mainly transformed from BM by microbial processes and was a dominant component of TOC in the deep-sea layer.

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.2
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• pp.259-266
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• 2006

A dual-channel glass coil sampling technique was used to measure hourly formaldehyde concentration in the ambient air. The dual-channel coil sampling assembly consists of three parts; an all-pyrex 28-turn coil made of 0.2-cm internal diameter glass tubing for gas-liquid contact and scrubbing of soluble gases, an inlet section upstream of the coil for introducing sample air and scrubbing solution, and a widened glass section downstream of the coil for gas-liquid separation. The scrubbing solution used was a dilute aqueous DNPH (dinitrophenylhydrazine) solution. Hourly concentration of formaldehyde was determined at a Gwangju semi-urban site during two intensive studies between September and October using the dual channel glass-coil/DNPH sampling technique and HPLC (High Performance Liquid Chromatography) analysis. The mean concentration was 1.7($0.4{\sim}4.7$) and 3.0($0.5{\sim}19.1$) ppbv for the September and October intensives, respectively, which are considerably low, compared to those measured in polluted urban areas around the world including several urban areas of Korea. The diurnal variation showed significant increase of formaldehyde in the daytime suggesting the dominance of formation of formaldehyde due to photochemical oxidation of methane and other hydrocarbons. An increase in the formaldehyde sometimes in the night might be due to an increase in primary source, i.e. traffic emissions. It was also found that rapid increase in formaldehyde levels from 3.0 to 19.1 ppbv in the afternoon on October 20 was due to plumes from burning of agricultural wastes such as rice straw and stubble. It is expected from the measurement data that the constructed dual-channel glass coil sampling system can be utilized for measuring atmospheric concentration of the formaldehyde with high time resolution.

• Microbiology and Biotechnology Letters
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• v.24 no.1
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• pp.9-18
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• 1996

Streptococcus mutans has been implicated as primary causative agents of dental caries by insoluble glucan (IG) in human and experimental animals. An attempt was made to search for the ${\alpha}$-1,3 glucanase that degrades IG produced by S. mutans. ${\alpha}$-1,3 glucanase was detected in the culture supernatant of microorganisms, which are isolated from soils on agar medium containing IG as a sole carbon source. This Streptomyces sp. hydrolysed IG produced by immobilized S. mutans and was named as Y9373. This enzyme required ${\alpha}$-1,3 glucan (IG) as an inducer. The optimum conditions for enzyme production were studied. The enzyme was purified by 30~70% $(NH_4)_2SO_4$ precipitation, anion exchange chroma tography on DEAE-cellulose and gel filtration on Sepadex G-75. The purified enzyme has a specific activity of 7840.0 U/mg protein giving 32.1-fold purification and final yield of 0.53%. The molecular weight was estimated to be about 22.5 kDa by SDS-PAGE. The optimum pH and temperature for enzyme reaction were 6.5 and 37$^{\circ}C$, respectively and the enzyme was relatively stable at the temperature below 60$^{\circ}C$. The activity of purified enzyme was enhanced by adding $Co^{2+},\;Mn^{2+}\;and\;Mg^{2+}$ into the medium, whereas inhibited by adding $Hg^{2+},\;Zn^{2+}$ and SDS. The $K_m\;and\;V_{max}$ value of ${\alpha}$-1,3 glucanase for IG were estimated to be 2.50 mM and 0.0431 mM/min, respectively. The thin layer chromatographic analysis of hydrolysates from IG with ${\alpha}$-1,3 glucanase showed that glucose was the main product of reaction. This enzyme activity was about 14 times higher than marketing dextranase as preventive agent against artificial dental caries by S. mutans in TH medium including 5% sucrose after 30 minutes.