• Journal of Environmental Science International
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• v.12 no.1
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• pp.35-40
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• 2003

With increasing population densities in cities, underground facilities and entertainment locations are proliferating at a rapid pace in efforts to maximize the use of land. The purpose of this study is to evaluate CO concentration level of subway stations having underground platforms in Busan Metropolitan City, from September to November 2000, over seven times. The places of inquiry include Yonsan-dong station, Somyon station, Busan station, Nampo-dong station and Dusil station. The samplings were conducted at three points of each station, i.e. gates, ticket gates, and platforms. The component of CO concentration is the main elements of indoor air quality evaluation. The total concentrations and average concentrations of CO were the higher at the Somyon station. The distribution of CO concentrations at each station, generally was higher at gate than ticket gates and platforms. The I/O ratios(I-platforms, 0-gates) were expressed highly than 1 at the Yonsan-dong station, Busan station, Nampo-dong station and were lower than 1 at the others.

• Journal of Environmental Science International
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• v.20 no.3
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• pp.385-394
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• 2011

Organotin compounds (OTs), namely butyltins compounds (BTs) and phenyltin compounds (PhTs), were measured in surface and core sediments collected in Jeju harbor. The horizontal and vertical distribution was examined and the relationship between the concentration of OTs and organic matter content and particle size distribution was also studied. BTs were detected in significant concentrations in sediments inside Jeju harbor. PhTs were detected in very low concentrations, compared to BTs. The main species in BTs and PhTs were dibutyltin (DBT) and monobutyltin (MBT), monophenyltin (MPhT), respectively. In the relationships between the concentrations of total BTs and organic carbon content, the significant correlations ($r^2$=0.4898 in surface sediments, $r^2$=0.53 in one core sediments) and no correlation in another core sediments obtained, which is estimated that the distribution of BTs in sediments were affected by several factors, such as their physicochemical properties including organic carbon content, and a tide, etc. In the relationships between the concentrations of total BTs and particle size (mud, sand, and gravel) in sediments, the concentrations of total BTs were higher in the sediments with higher mud content, indicating that higher BTs were distributed with increasing sediments of fine granules.

• Journal of The Korean Society of Agricultural Engineers
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• v.52 no.3
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• pp.65-71
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• 2010

This study was conducted to investigate the dynamics of nutrients such as total nitrogen (TN), nitrate nitrogen ($NO_3$-N) total phosphorous (TP), and phosphate phosphorous ($PO_4$-P) in outflow from a cabbage farmland in a mixed land-use watershed. The TN concentrations in groundwater showed twice peaks in late July 2006 and late March 2007 (3.8, 4.7 mg/L, respectively), when it rained shortly after fertilizer application, indicating that nitrogen leaching is greatly influenced by fertilization and rainfall. The mean concentrations of TN and $NO_3$-N in surface water were not significantly higher than those in groundwater, while the mean concentrations of TP and $PO_4$-P in surface water were significantly (p < 0.05) were higher than those in groundwater. The TN concentrations in groundwater were generally higher than those in surface water during fertilization and early growing season due to the effect of fertilization, but vice versa in the other periods. In contrast, the TP concentrations in groundwater were always lower than those in surface water due to the sorption of particulate phosphorous by soil. The ratio of TN load in baseflow to that in total TN load (39 %) was much greater than the TP ratio (7 %), suggesting that baseflow contribute to nitrogen export. Therefore, proper fertilization management should be taken to reduce nitrogen load through baseflow.

• Korean Journal of Environmental Biology
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• v.22 no.3
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• pp.426-437
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• 2004

To understand the phytoplankton community in adjacent waters of Ulchin nuclear power plant (UNPP), abundance and the size fractionated $chl-\alpha$ concentrations were evaluated through seasonal interval sampling from April 2003 to February 2004. A total of 211 different phytoplankton species was observed and mean abundance of phytoplankton in each study period ranged from 244,286 to 1,221,779 cells $L^{-1}$. The contributions of microplankton $(>20\mu{m})$ to total phytoplankton abundance ranged from 42.5 to 83.6% (average 66.1%) and those of nanoplankton $(>20\mu{m})$ ranged from 16.4 to 57.5% (average 33.9%). Total chl-$\alpha$ concentrations of phytoplankton ranged from 0.52 to $2.26\mu{g}\;L^{-1}$. The contribution of chl-$\alpha$ concentrations of microplankton was higher than that of nano- and picoplankton through the study period with exception of July 2008. The results of abundances and $chl-\alpha$ concentrations suggest that microplankton has an important role in adjacent waters of UNPP. The diminution of abundances and $chl-\alpha$ concentrations of phytoplankton was observed after passage through the cooling water system, but it was gradually recovered by mixing with the ambient waters. Our results suggested that the influence of thermal discharges on phytoplankton should be restricted within narrow limits around outlet area of thermal effluents.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.25 no.4
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• pp.584-590
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• 2015

Objectives: The purpose of this study was to evaluate quartz concentrations in airborne total and respirable dusts. Materials: Respirable dust samples were collected using a 10 mm aluminum cyclone equipped with a 37 mm$5{\mu}m$ pore size PVC filter. Total dust samples were collected with a three stage cassette from three work sections at earthwork sites located in the South Chungcheong-do Province area. Results: The geometric means of quartz concentrations were $0.008mg/m^3$ and $0.004mg/m^3$ in total dust and respirable dust, respectively. The geometric means of quartz contents analyzed by FTIR were 3.74% in total dust and 3.16% in respirable dust. The geometric mean of quartz concentrations and contents in secondary blasting operations were higher than those in other operations. Conclusions: Given that secondary blasting operations had higher quartz concentrations, there is a need to reduce respirable dust, such as through wet operations.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.3
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• pp.525-530
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• 1998

The effects of godulbaegi(Ixeris sonchifolia H.) powder on body weight gain, lipid and protein concentrations, and enzyme activities were studied in growing male rats for 4 and 8 week. The fats (Sprague-Dawley) were fed diets containing 5% godulbaegi or without. The body weght gain, food efficiency ratio, protein efficiency ratio, hemoglobin concentration and hematocrit value of rats fed godulbaegi diet were similar to the control diet. The ratio of spleen weight to body weight in godulbaegi group for 8 weeks was greater than in that of control group, but they were similar both feeding groups in liver and kidney. The concentrations of the total lipid and triglyceride in serum were increased in rats fed godulbaegi diet for 4 week than in those fed control diet, but those were decreased in rats fed godulbaegi diet for 8 week than in those fed the control diet. The concentrations of the phospholipid, total cholestrol and HDL-cholestrol in serum were decreased in rats fed godulbaegi diet for 8 week than in those fed control diet. The HDL-cholestrol/total cholestrol ratio and athergenic index were similar to both diet groups. There were no differences in growth, serum total protein, albumin concentrations, aspartate aminotransferase and alanine aminotransferase activities between rats fed godulbaegi diet and those fed the control diet.

• Preventive Nutrition and Food Science
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• v.7 no.4
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• pp.367-372
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• 2002

This study investigated the effects of dietary soy protein and Ca on the lipid profiles of rats fed fat-enriched diets. Rats were divided into two groups and fed either a casein-low Ca (Exp I) or ISP-high Ca diet (Exp II) for a control period of 4 weeks. The two groups of rats were again subdivided into 4 groups and fed one of 4 experimental diets for another 4 weeks. The experimental diets consisted of 18% beef tallow and 1 % cholesterol, in which either 20 % casein or ISP with one of two levels of Ca, high (1 %) or low (0.1 %). The concentrations of total lipid, cholesterol and triglyceride in serum, liver and feces were determined. At the end of the control period, the serum total lipid and cholesterol concentrations were low in the rats fed ISP-high Ca diet (67~76% and 83~86%). During the next 4 week period, these concentrations remained significantly lower in rats fed the diets containing ISP and high Ca compared with those on casein and low Ca diets (p ＜ 0.05). Total lipid and cholesterol concentrations in feces were significantly higher in the ISP-high Ca dietary group at 4 weeks, and high in both high Ca groups at 8 weeks. This study demonstrates that both soy protein and Ca reduce serum and liver cholesterol, triglyceride, and total lipid in rats fed fat-enriched diet, and that they have an additive effect when combined.

• Journal of Nutrition and Health
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• v.37 no.7
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• pp.515-524
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• 2004

This study was performed to investigate effect of dried powders and ethanol extracts of garlic flesh and peel on lipid metabolism and antithrombogenic capacity in 16-month-old rats. Forty Sprague-Dawley male rats weighing 618.1$\pm$6.5 g were blocked into five groups according to body weight and raised for 3 months with control and experimental diets containing 5% (w/w) of dried powders of garlic flesh or peel, or ethanol extracts from equal amount of each dried powder and control diet. Plasma and liver total lipids, triglyceride and total cholesterol, and plasma HDL-cholesterol, throm-boxane $B_2$ (TX $B_2$), 6-keto-prostaglandin $F_{1a}$ (6-keto-PG $F_{1a}$) concentrations were measured. Total, insoluble and soluble dietary fibers contents were highest in peel powder followed by fresh powder, and those in ethanol extracts of flesh and peel, especially soluble, very low. Plasma and liver total lipids, triglyceride, and total cholesterol concentrations were lower in all the garlic experimental groups compared to Especially, flesh and peel powder lowered plasma total lipids, triglyceride and total cholesterol concentrations markedly, and flesh powder and flesh ethanol extract lowered liver total lipids, triglyceride and total cholesterol concentration remarkably. Plasma TX $B_2$ concentrations in garlic experimental groups were lower than that of control group, and 6-keto-PG $F_{1a}$ concentrations. In garlic experimental groups were higher than that of control group. Flesh ethanol extract group showed the lowest TX $B_2$ and the highest 6-keto-PG $F_{1a}$ concentrations among experimental groups, so TX $B_2$/6-keto-PG $F_{1a}$ ratio in flesh ethanol extract group was significantly lower than that of control group. Moreover, clotting time was significantly increased in flesh ethanol extract group as compared to control group. In conclusion, intakes of dried powders and ethanol extracts of garlic flesh and peel were effective in lowering lipid levels of liver and plasma. And also flesh ethanol extract diet was most effective in antithrombogenic activity among garlic experimental groups as TX $B_2$/6-keto-PG $F_{1a}$ ratio in flesh ethanol extract group was significantly lower and clotting time was significantly increased in this group as compared to control group.ntrol group.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.4
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• pp.385-390
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• 1997

Fifteen Ettawah-cross does were used to study maternal serum concentrations of total triiodothyronine ($T_3$), teraiodothyronine ($T_4$) and cortisol in different status of pregnancy (nonpregnant, aborted, single and twin-bearing does) during late pregnancy. Analysis of the data indicated that here was no significant changes in total $T_3$, $T_4$, and cortisol concentrations with the advance of pregnancy. Concentrations of $T_3$, $T_4$, and cortisol decreased by 38.9, 34.9, and 32.6%, and 12.0, 15.7 and 27.6%, and 41.6, 44.0, and 43.7% in the aborted, single and, twin-bearing, respectively, as compared to those nonpregnant does. These was no significant difference in concentrations of $T_3$ and cortisol between aborted, single and twin-bearing does, and in those of $T_4$ between aborted and single-bearing does. However, $T_4$ concentrations in twin-bearing were lower by 17.7 and 14.1% than those in aborted and single-bearing does, respectively. The decreased concentrations of thyroid hormones in pregnant does suggested that fetus could have increased iodine uptake from maternal circulation causing a decrease in the availability of this nutrient for synthesis of maternal thyroid hormones. The decreased concentrations of cortisol could have been associated with the increased metabolism of the hormone to regulate nutrients influx into the placenta of pregnant does.

• Journal of Environmental Health Sciences
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• v.13 no.2
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• pp.25-33
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• 1987

This study was carried out to evaluate student exposures to dust in classroom of middle schools. A total of four schools, such as two in an urban and two in a rural area, were selected for this study. In this study, airborne dust concentrations were measured during a period from July 8 to July 18, 1986. Additional measurements of dust concentrations were conducted from November 4 to 7, 1986 to compare the results by seasonal variation. The results of this study were as follows. 1. Respirable dust concentrations were measured by both filtration method (C mg/m$^3$) and Digital Aerosol Monitor (cpm) to calculate anexchange factor K. K- value was 0.159 as follows. $K=\frac{c}{cpm} = \frac{2.71}{17.09} = 0.159$ 2. In summer when windows were opened, the concentrations of airborne respirable dusts measured by filter sampling method were 0.54-1.37 mg/m$^3$ in the morning and 0.79-1.75 mg/m$^3$ in the afternoon. Thus, higher levels were indicated in the afternoon. Meanwhile, the concentrations of airborne respirable dusts measured in winter were approximately twice as high as those in summer. 3. The highest dust concentrations were determined in School D which is a coeducational school with classroom of concrete floor. Walking roads in School D were not paved and students did not wear indoor-shoes. Dust levels in School D were approximately twice as high as levels in School B. All of the measured dust levels in four schools exceeded Korean Standard for outdoor air, 0.3 mg/m$^3$ for 24 hours. Results by Digital Aerosol Monitor indicated that there was no significant difference in dust levels among grades. The concentration of airborne dusts in the classroom was 1.5-3.0 times higher than that in the hall way. The concentration of airborne dusts during recess was 1.3-1.6 times higher than that during class. In winter, the dust concentrations during clean-up exceeded the permissible exposure limit, 10 mg/m$^3$ (as total dusts), for occupational exposures. 4. The concentrations of total dusts measured in winter were 1.5-2.4 times higher than those of respirable dusts measured simultaneously.