• The Korean Journal of Mycology
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• v.13 no.3
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• pp.149-156
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• 1985

The study was carried out to find effects of the saponins that were extracted from red ginseng on the growth of, aflatoxins production by, and protein patterns of Aspergillus flavus NRRL 3357. A. flavus with $10^6$ conidia as grown at $30^{\circ}C$ for seven days on the enriched medium. Mycelial growth and pH changes of medium which cultured the mold, were similar to those of the control group. However, aflatoxin which produced by the mold was less than that of the control in all concentration of the saponin. To be more specific, 0.3 % of the saponin inhibited production of aflatoxin $B_1$ and $G_1$ to the extent of 31.6 and 21% of the control. The protein peaks of A. flavus at the fourth day of the culture were shown high intensity near the level of 14,300 daltons. However, the mold which cultured in the medium containing the saponin showed low intensity of protein than that of the control group on all molecular weight.

• The Journal of Engineering Geology
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• v.21 no.4
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• pp.313-322
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• 2011

On September 2007, numerous slopes at Jeonranam-Do collapsed as a result of rainfall related to Typhoon Nari. Failure occurred at a road cut-slope on the ${\bigcirc}{\bigcirc}$ detour road, damaging transport infrastructure. This study aims to determine the cause of failure based on field investigations, the geotechnical properties of soil, clay mineral composition, and quantitative analysis. The studied cut slope consists of weathered soil that originated from volcanic rocks, and minor faults and a mafic dyke. Surface water tends to seep into the soil because the roadway is not sealed and because of poorly installed drainage. Sieve and XRD analyses indicate that soils in the failure zone are ML and CH, which are prone to swelling due to the presence of clay minerals such as smectite and vermiculite. The slope failed due to the improper construction of drainage facilities, the presence of geological weak zones, and high soil contents of swelling clay.

• Korean Journal of Clinical Laboratory Science
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• v.39 no.1
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• pp.49-55
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• 2007

HCV is a single-stranded RNA virus and more than 1 million new cases are reported annually worldwide. The six major HCV genotypes and numerous subtypes vary in their geographic distribution. It is thought that genetic heterogeneity of HCV may account for some of the differences in disease outcome and response to treatment observed in HCV infected persons. In this study, we determined HCV genotypes among chronic Korean HCV patients and evaluated direct sequence PCR protocols developed. For the study, 232 chronic HCV patient sera were used. HCV RNA was extracted and two pairs of consensus PCR primers were selected in 5'UTR region for amplification of HCV RNA. Amplification products obtained from the HCV positive cases were subjected to automatic sequencing. Sequences were compared with those in GenBank by using the BLAST program. From this study, five HCV genotypes, 1b, 2a, 2b, 2c and 3a were found. HCV genotypes 4, 5 and 6 were not determined. HCV genotype 1b (53.9%, 125/232) and 2a (35.8%, 83/232) were most frequently found. This group was followed by 2b (3.9%, 9/232), 3a (3.4%, 8/232) and 2c (3.0%, 7/232). The data presented here suggest a complex distribution of HCV types and they were well correlated with other reports on Koreans and will be helpful for type-specific follow-up of Korean HCV patients. This study showed that 5'UTR direct sequence analysis is a sensitive and rapid method to identify HCV genotypes.

• Korean Journal of Food Science and Technology
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• v.33 no.6
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• pp.784-788
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• 2001

Reliable data on the exposure of capsaicin, which evokes hot sensation in hot red pepper, are important prerequisites for studying biological functions of capsaicin in human body since its roles are controversial according to animal and epidemiological studies. To get accurate data, the use of urinary biomarkers was considered as a measure of internal exposure of capsaicin. After 2-day-capsaicin depletion five to six women in their 20's were instructed to eat 60 or 80 g/day hot red pepper soybean paste as a capsaicin source with meal which did not contain capsaicinoid, and to collect their urine separately. HPLC conditions were set to detect capsaicinoid and urinary metabolites at the same time. Most of capsaicinoid were excreted in the form of 4-hydroxy-3-methoxybenzoic acid in three subjects at the highest dose. This result suggests the oxidation of the 4-hydroxy3-methoxybenzaldehyde, the hydrolysis product of capsaicin, is the major metabolic pathway in the human body, whereas the reduction of the aldehyde is the major route in rats. However, neither any metabolite nor the parent compound was ever shown in two of the subjects reflecting large individual differences of capsaicin absorption and/or biotransformation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.5
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• pp.727-738
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• 1998

Seasonal species composition of fishery resources was determined using samples collected by a stow net from April 1995 through January 1996 at 9 stations off Youngkwang. Catch data obtained from a set net using strong tidal current could be used for a quantitative analysis of dominant species. Of the 98 species identified, assemblages were consisted of $52.0\%$ in fishes, $44.6\%$ in shrimps, $2.0\%$ in cephalopods, $1.4\%$ in crabs and <$0.1\%$ in gastropods. Thryssa kammalensis, Crangon hakodatei, Metapenaeus joynezi and Johnius grypotus predominated in abundance, consisting of $68\%$ in the number of individuals, The abundance and species composition fluctuated seasonally, and species could be distinguished by life history pattern with seasons. Seasonal variation in species composition was greater than the spatial variation in a sampling period, As the fine sediment was predominated in the study area, the species composition were significantly different from those of other coastal waters of West Sea, Korea.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.2
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• pp.190-194
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• 2008

Physicochemical properties of the green tea component enriched mushroom (Flammulina velutipes) were investigated. The yield of mushroom was highest with green tea powder untreated sample and the yield was decreased by the addition of green tea powder. However, hardness was increased by the addition of green tea powder. Analysis of catechins and caffeine in mushrooms showed that catechins were not transferred into mushrooms, whereas caffeine content was increased. The content of total polyphenol in mushroom was not affected by the addition of green tea powder and crude catechins. Analyses of aroma patterns using the electronic nose based on GC with SAW sensor showed that new peaks occurred from 3 to 6 sec in green tea added mushroom. This study showed that functional components and quality of mushroom were possibly improved by incorporating green tea powder in growth medium.

• Progress in Medical Physics
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• v.15 no.4
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• pp.215-219
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• 2004

Due to their excellence for the high-energy therapy range of photon beams, researchers show increasing interest in applying MOSFET dosimeters to low- and medium-energy applications. In this energy range, however, MOSFET dosimeter is complicated by the fact that the interaction probability of photons shows significant dependence on the atomic number, Z, due to photoelectric effect. The objective of this study is to develop a very detailed 3-dimensional Monte Carlo simulation model of a MOSFET dosimeter for radiological characterizations and calibrations. The sensitive volume of the High-Sensitivity MOSFET dosimeter is very thin (1 ${\mu}{\textrm}{m}$) and the standard MCNP tallies do not accurately determine absorbed dose to the sensitive volume. Therefore, we need to score the energy deposition directly from electrons. The developed model was then used to study various radiological characteristics of the MOSFET dosimeter. the energy dependence was quantified for the energy range 15 keV to 6 MeV; finding maximum dependence of 6.6 at about 40 keV. A commercial computer code, Sabrina, was used to read the particle track information from an MCNP simulation and count the tracks of simulated electrons. The MOSFET dosimeter estimated the calibration factor by 1.16 when the dosimeter was at 15 cm depth in tissue phantom for 662 keV incident photons. Our results showed that the MOSFET dosimeter estimated by 1.11 for 1.25 MeV photons for the same condition.

• Journal of Life Science
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• v.17 no.11
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• pp.1464-1471
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• 2007

Diabetes mellitus is a chronic metabolic disorder, leading to many complications including cognitive deficit. Regular exercise has often been recommended as a therapeutic maneuver to the diabetic patients for the prevention of secondary complications. In the present study, the effects of treadmill exercise on memory and brain-derived neurotrophic factor (BDNF) in the hippocampus of streptozotocin (STZ)-induced diabetic rats were investigated. Male SD rats, aged 6 weeks, were randomly assigned to the following three groups: control group(n=8), STZ-induced diabetic group(n=8), and STZ-induced diabetes and exercise group(n=8). Diabetes was induced by a single injection of STZ (50 mg/kg body weight). Treadmill running was conducted with duration and frequency of 30 minutes and 5 times per week, respectively, for 8 weeks. Memories were tested in the Morris water maze. Western blotting was performed to detect BDNF expression in the hippocampus. In this study, we found that compared to the control group, the STZ-induced diabetes group had a significantly impaired cognitive performance along with suppressed BDNF expression in the hippocampus and the exercise group had a higher cognitive function in diabetic rats. Therefore, the current findings of the study show that a treadmill running exercise can improve diabetes-induced impairment of cognitive function. And the improved cognitive function appears to be related to an alleviation in diabetes-induced BDNF expression in hippocampus.

• Korean Journal of Construction Engineering and Management
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• v.19 no.4
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• pp.52-60
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• 2018

In the construction industry, attempts to evaluate the environmental impact of products through life cycle assessment (LCA) approach has been on the rise. However, the domestic construction industry needs to make rapid decisions due to limited budget and schedule, so it is difficult to carry out a review of the environmental load on all resources. The decision-making process requires information on the major influence factors that should be focused on to reduce environmental load. And this information should be quantified so that it can be linked to environmental impact assessment. In this study, the LCA results of road construction cases were analyzed to provide such information. As a result, diesel, ready-mixed concrete, urethane-based paint, aggregate, and asphalt concrete were found to be the main factors that generated 93.17% of the environmental load in the earthwork type of road project. The total environmental cost caused by these affecting factors when constructing 1 km of earthwork type of road project is 242 million won. The analysis also shows that a 10% reduction in the amount of ready-mixed and asphalt concretes can reduce carbon emissions by 5.02% and 2.28% while reducing environmental costs by 11 million won per kilometer. In order to reduce carbon emissions of the earthwork type of road project, it is necessary to actively develop and introduce new methods and eco-friendly materials to reduce the overall use of ready-mixed concrete and asphalt concrete.

• Korean Journal of Food Science and Technology
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• v.48 no.5
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• pp.424-429
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• 2016

Globally, obesity has been recognized as a serious health problem. Recently, slimming foods for weight loss and maintenance were found to contain anti-obesity drugs, their analogues, and prohibited ingredients. To avoid inspections by the Government, structurally modified analogs have been continuously synthesized. For rapid determination of adulterated slimming products, we simultaneously analyzed 21 illegal compounds using liquid chromatography (LC) equipped with photo diode array, and LC coupled with tandem mass spectrometry. The validation of the method was performed with regard to selectivity, linearity, limit of detection, limit of quantification, precision, and accuracy. We purchased 128 samples from the Korean market and online sources in the year 2015. In 31 samples, 3 illegal compounds were detected as follows: 9.9-135.3 mg/g of sibutramine, 0.2-17.5 mg/g of yohimbine, and 1.8 mg/g of icariin. This simultaneous detection method might prove to be a simple and rapid analysis for monitoring illegal compounds in slimming foods.