• Title/Summary/Keyword: concentrations

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무선 연속 당측정기에 의한 정상 개의 당 농도 평가 (Evaluation of Glucose Concentration by Wireless Continuous Glucose Monitoring System in Healthy Dogs)

  • 강지훈;김성수;양만표
    • 한국임상수의학회지
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    • 제27권4호
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    • pp.392-396
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    • 2010
  • Blood glucose curves in the management for diabetic patients have several limitations including intermittent assessment of blood glucose concentration, hospitalization, patient restraint, and repeated phlebotomy. The aim of this study was to apply and evaluate a wireless continuous glucose monitoring system (CGMS) in healthy dogs. Subcutaneous interstitial glucose concentrations in 7 dogs were continuously monitored and recorded by wireless CGMS. During induced hyperglycemia, the interstitial glucose concentrations were compared with whole blood glucose concentrations measured by glucometer and serum glucose concentrations measured by automated chemistry analyzer, respectively. There were no significant differences among interstitial, whole blood and serum glucose concentrations. The interstitial glucose concentrations had a good correlation to serum glucose concentrations. The real-time wireless CGMS is a valuable tool for monitoring system of glucose concentrations in dogs. Use of the CGMS for diabetic patients will provide accurate information over traditional blood glucose curves.

대구지역 주요 도로변 대기오염물질의 농도 특성 (Characteristics of Air Pollutant Concentrations Near Major Roadways in Daegu)

  • 조완근;최성락
    • 한국환경과학회지
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    • 제15권8호
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    • pp.737-744
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    • 2006
  • Present study was designed to characterize the concentrations of major roadside air pollutants in Daegu and to compare with those of Seoul and Busan. Evaluated were the exceedance frequence of mean concentrations of target compounds(CO, NO$_2$, O$_3$, PM$_{10}$, SO$_2$) and the relationship for time variation. Two air pollution monitoring stations(one roadside station and one residential station) in Daegu were selected for this study. In addition, one roadside monitoring station from each of Seoul and Busan was chosen for the comparison of Daegu monitoring stations. The data analyzed in the current study were collected from 1998 to 2000 by Daegu Regional Environmental Management Office. The roadside concentrations of NO2 and PM to and the exceedance frequency of ambient air standard levels in Daegu were higher than those of Seoul and Busan. Except 03, the roadside concentrations of all target compounds showed following three distinguished patterns; first, possibly due to increased traffic density, the concentrations increased from 0500 to 0900(LST), second, the concentrations decreased from 0900 to 1700(LST) possibly due to the increased wind velocity and decreased traffic density, and finally, increased traffic density, the concentrations increased again from 1700 to 2100(LST). An implication was that major air pollution sources shifted from residential area to road-area during rush hours.

서울시 일부 지하철 역사 내 공기 중 진균 농도에 관한 연구 (Assessment of Airborne Fungi Concentrations in Subway Stations in Seoul, Korea)

  • 조준호;백남원
    • 한국환경보건학회지
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    • 제35권6호
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    • pp.478-485
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    • 2009
  • This study was performed to assess airborne fungi concentrations during fall in eight subway stations in Seoul, Korea. The purpose of this study was to investigate appropriate culture media and evaluate factors affecting airborne fungi concentrations. Results indicated that airborne fungi concentrations showed log-normal distribution. Thus, geometric mean (GM) and geometric standard deviation (GSD) were calculated. The GM of airborne fungi concentrations cultured on malt extract agar (MEA) media was 466 $cfu/m^3$ (GSD 3.12; Range 113~4,172 $cfu/m^3$) and the GM of concentrations cultured on DG18 media was 242 $cfu/m^3$ (GSD 4.75; Range 49~6,093 $cfu/m^3$). Both of GM values exceeded 150 $cfu/m^3$, the guideline of World Health Organization (WHO). There was no significant difference between two fungi concentrations cultured on MEA and DG18 media, respectively. Two factors, such as relative humidity and depths of subway stations were significantly related to airborne fungi concentrations. It is recommended that special consideration should be given to deeper subway stations for improvement of indoor air quality.

정상인과 도금업 근로자의 요 및 혈청중 크롬 및 니켈 농도 (Chromium and Nickel Concentrations in Urine and Serum of None Exposed Group and Workers in Electroplating Plants)

  • 최호춘
    • 한국산업보건학회지
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    • 제5권1호
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    • pp.1-7
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    • 1995
  • The exposure levels of chromium and nickel for chromeplating workers were evaluated. Chromium and nickel concentrations in urine and serum from 82 exposed workers and 69 controls, who were not exposed occupationally to metals, were analyzed by flameless atomic absorption spectrophotometry. The results were as follows: 1. Chromium concentrations in urine of exposed group and control were $3.49{\pm}1.83g/g$ of creatinine, $5.59{\pm}2.83g/g$ of creatinine, and in serum were $0.69{\pm}0.30g/l$, $2.31{\pm}1.16g/l$ respectively. There were significant difference of concentrations for chromium in urine and serum by group respectively. 2. Nickel concentrations in urine of exposed group and control were $0.92{\pm}0.23g/g$ of creatinine, $2.20{\pm}1.93g/g$ of creatinine, and serum concentrations were $0.52{\pm}0.34g/l$, $1.41{\pm}0.74g/l$ respectively. There were significant difference of concentrations for nickel in serum by groups statistically. 3. Chromium and nickel concentrations in urine and serum of exposed groups were not significant by workplaces(grinding, electroplants, packaging).

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톨루엔 흡입이 뇌중 Monoamine 및 그대사물의 농도에 미치는 영향에 관한 연구 (Effects of Toluene Inhalation on The Concentrations of The Brain Monoamines and Metabolites)

  • 김대병;이종권;정경자;윤여표
    • Toxicological Research
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    • 제14권4호
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    • pp.495-500
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    • 1998
  • The effect of acute toluene exposure on behaviour and monoamine concentrations in the various brain regions were investigated in the rat. Toluene was adminstered via inhalation to rats at concentrations of 0, 1000, 10000, 40000 ppm for 20 min. During exposure to toluene, spontaneous locomotor activity was counted. After exposure, animals were sacrificed instantly and brains were separated. Regional concentratons of brain monoamines (norepinephrine, NE; dopamine, DA; 5- hydroxytryptamine, 5-HT) and its metabolites (3,4-dihydroxyphenylacetic acid, DOPAC; homovanillic acid, HVA; 5-hydroxyindole-3-acetic acid, 5-HIAA) were determined. The changes in locomotor activity during toluene exposure depended on the toluene concentration. At 1000 ppm concentration, spontaneous locomotor activity increased initially and thereafter decreased. At higher concentrations (10000 ppm and 40000 ppm), spontaneous locomotor activity decreased and eventually ceased. A regional analysis of VA, NE, 5-HT, VOPAC, HVA, and 5-HIAA indicated a significant decrease in VA concentrations in cerebellum and striatum while NE and 5-HT concentrations were significantly increased in the cerebellum and cortex. 5-HIAA concentrations were significantly increased in all brain regions. DOPAC concentrations were significantly increased in cerebellum and cortex while decreased in striatum. These results especially indicated that metabolic conversion of DA to HVA in striatum was highly increased by toluene inhalation. However, It remains to elucidate between behavioural responses and monoamine changes.

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Bioaccumulation of copper and zinc by the giant kelp Macrocystis pyrifera

  • Evans, La Kenya;Edwards, Matthew S.
    • ALGAE
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    • 제26권3호
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    • pp.265-275
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    • 2011
  • This study examined the bioaccumulation of the heavy metals copper (Cu) and zinc (Zn) by the giant kelp, Macrocystis pyrifera, by exposing meristematic kelp tissue to elevated metal concentrations in seawater within laboratory aquaria. Specifically, we carried out two different experiments. The first examined metal uptake under a single, ecologically-relevant elevation of each metal (30 ppb Cu and 100 ppb Zn), and the second examined the relationships between varying levels of the metals (i.e., 15, 39, 60, 120, 240, and 480 ppb Cu, and 50, 100, 200, 300, 500, and 600 ppb Zn). Both experiments were designed to contrast the uptake of the metals in isolation (i.e., when only one metal concentration was elevated) and in combination (i.e., when both metals' concentrations were elevated). Following three days of exposure to the elevated metal concentrations, we collected and analyzed the M. pyrifera tissues using inductively coupled plasma atomic emissions spectroscopy. Our results indicated that M. pyrifera bioaccumulated Cu in all treatments where Cu concentrations in the seawater were elevated, regardless of whether Zn concentrations were also elevated. Similarly, M. pyrifera bioaccumulated Zn in treatments where seawater Zn concentrations were elevated, but this occurred only when we increased Zn alone, and not when we simultaneously increased Cu concentrations. This suggests that elevated Cu concentrations inhibit Zn uptake, but not vice versa. Following this, our second experiment examined the relationships among varying seawater Cu and Zn concentrations and their bioaccumulation by M. pyrifera. Here, our results indicated that, as their concentrations in the seawater rise, Cu and Zn uptake by M. pyrifera tissue also rises. As with the first experiment, the presence of elevated Zn in the water did not appear to affect Cu uptake at any concentration examined. However, although it was not statistically significant, we observed that the presence of elevated Cu in seawater appeared to trend toward inhibiting Zn uptake, especially at higher levels of the metals. This study suggests that M. pyrifera may be useful as a bio-indicator species for monitoring heavy metal pollution in coastal environments.

국민건강영양조사 제4기 2차년도 (2008)를 이용한 어패류 섭취빈도에 따른 한국 성인의 혈중 중금속 농도 조사 (Blood Heavy Metal Concentrations of Korean Adults by Seafood Consumption Frequency: Using the Fourth Korea National Health and Nutrition Examination Survey (KNHANES IV), 2008)

  • 김영아;김영남;조경동;김미영;김은진;백옥희;이복희
    • Journal of Nutrition and Health
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    • 제44권6호
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    • pp.518-526
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    • 2011
  • To determine blood heavy metal concentrations by seafood consumption in Korean adults, blood cadmium, mercury, and lead concentrations in a representative sample of 1,709 Koreans participated in the Fourth Korea National Health and Nutrition Examination Survey (KHANES IV-2) in 2008 were analyzed by age and seafood consumption frequency. The mean blood cadmium, mercury, and lead concentrations were $1.14{\pm}0.73{\mu}g/L$, $5.50{\pm}3.83{\mu}g/L$, and $2.56{\pm}1.22{\mu}g/dL$, respectively. The subjects aged ${\geq}$ 50 years had significantly higher blood cadmium concentrations than the subjects aged 20~39 years. Blood mercury concentrations of the 50's were significantly higher than those of the 20's and 30's (p < 0.05). Approximately, 43% of males and 22% of females had blood mercury concentrations > $5.8{\mu}g/L$ which is a blood mercury level equivalent to the current Reference Dose. Only 2 subjects had lead concentrations > $10{\mu}g/dL$, the standard lead level by the Centers for Disease Control and Prevention, USA. The subjects consuming pollack, mackerel, anchovy, corvina, shellfish, and salted seafood at least once a week had significantly higher mercury concentrations than the subjects consuming those seafoods less than once a month. However, there were no clear relationships between blood cadmium and lead concentrations and seafood consumption frequencies.

식이내 단백질과 철분수준이 흰쥐의 Fe, Cu 및 Zn 대사에 미치는 영향 (Effect of Different Levels of Dietary Protein and Iron on the Fe, Cu and Zn Metabolism in Rats)

  • 정해랑;김미경
    • Journal of Nutrition and Health
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    • 제15권4호
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    • pp.258-267
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    • 1982
  • This study was performed to investigate the effect of different levels of protein and iron in the diet upon Fe, Cu and Zn metabolism in rat during four weeks of growing period. Forty-five male weanling rats of Sprague-Dawley strain weighing $68.5{\pm}1.1g$ were divided into 9 groups and each group was given with one of the 9 different kinds of diets for four weeks. The three dietary protein levels used were 5, 20 and 40% and Fe levels 0, 35, and 350 ppms. The results obtained were summarized as following ; 1) Food intake and body weight gain in 20%(SP) and 40%(HP) dietary protein groups tended to be significantly higher than 5%(LP) protein groups. Protein efficiency ratio (PER) was higher in LP groups than in HP and SP groups. With dietary Fe levels, there were no significant differences among groups in food intake, body weight gain, and PER. 2) In LP groups, the Fe concentrations in liver, kidney, and hind limb muscle were higher than in SP and HP groups. Regarding with dietary protein levels, the liver Cu concentrations in LP groups were slightly higher, but the liver Zn concentrations were lower in LP groups. The Fe concentrations in liver and kidney tended to decrease with decrease in dietary Fe levels, but Cu and Zn concentrations showed no consistent tendency with dietary Fe levels. 3) The Fe, Cu and Zn concentrations in serum were not different from dietary treatments except that the serum Fe concentrations increased slightly in LP groups. 4) The Fe and Cu concentrations in urine tended to be higher in HP groups. Fecal Cu and Zn concentrations showed no significant differences in dietary protein or Fe levels, but the Fe concentrations tended to increase with increase in dietary Fe levels.

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강릉·태백지역 석탄광산의 탄 및 호흡성 탄분진중 금속 농도 비교에 관한 연구 (Determination of Metals of Coal and Respirable Coal Dust in Gangneung and Taebaek Coal Mines)

  • 김해정;최호춘;정호근
    • 한국산업보건학회지
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    • 제1권1호
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    • pp.82-88
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    • 1991
  • Determination of Cu, Fe, Ni, Pb, and Zn concentrations in coal and respirable coal dust were performed by atomic absorption spectrophotometry. The coal samples of 18 coal mines in Gangneung area were collected and 25 coal mines in Taebaek area. Crushed coal samples were divided into three mesh sizes. The results were as follows : 1. Metal concentrations of coals in Gangneung area by sieve sizes( -100/+200 mesh, -200/+325 mesh, -325 mesh) were as follows: Cu ; 20, 18, 19, Fe ; 1,830, 1,765, 1,107, Pb ; 6, 8, 14, Ni ; 17, 17, 14, Zn ; 4, 2, $4{\mu}g/g$, respectively. Metal concentrations in coals in Taebaek area by sieve sizes(-100/+200 mesh, -200/+325 mesh, -325 mesh) were as follows: Cu ; 30, 32, 26, Fe ; 1,741, 1,822, 1,773, Pb ; 8, 9, 7, Ni ; 13, 13, 13, Zn ; 8, 5, $4{\mu}g/g$, respectively. There were not significant differences of Cu, Fe, Ni, Pb, and Zn concentrations of coals statistically in Gangneung and Taebaek area by sieve size. 2. Metal concentrations of coals in Gangneung and Taeback area were as follows : Cu ; 19, 30, Fe ; 1,514, 1,778, Pb ; 9, 8, Ni ; 16, 13, Zn ; 3, $6{\mu}g/g$, respectively. Differences of copper and zinc concentrations of coal samples were significant between Gangneung and Taebaek area, but those of iron, nickel and lead concentrations were not significant. 3. Copper, iron, lead, nickel and zinc concentrations of coals and respirable coal dust were as follows : Cu ; 30, 6, Fe ; 1,779, 5,075, Pb ; 8, 7,814, Ni ; 13, 5,681, Zn ; 5, $134{\mu}g/g$, respectively. Differences of nickel, lead and zinc concentrations were significant between coals and respirable coal dust but those of copper and iron concentrations were not significant.

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Long-Term Investigation of Regional Topographic Effects on Soil Chemical Properties and Heavy Metal Concentrations in Paddy Fields

  • Ahn, Byung-Koo;Kang, Seong-Soo;Shin, Jae-Yeon;Lee, Jin-Ho
    • 한국토양비료학회지
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    • 제45권5호
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    • pp.738-743
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    • 2012
  • Topographic conditions of agricultural fields work as a important factor to identify different soil properties. This study was conducted to investigate the selected soil chemical properties and the concentrations of heavy metals, Cd, Cr, Pb, Cu, Ni, and Zn, in the paddy fields of different topographic areas at four year intervals from 1999 to 2011. Three-hundred soil sampling sites in the paddy fields were selected from the different topographic areas that were local valley and fans, fluvio-marine deposits, alluvial plains, and diluvial terraces. The mean values of soil pH ranged 5.7~5.8 that were within optimal range for rice cultivation. The mean values of other properties such as soil organic matter (SOM) content, the concentrations of exchangeable cations, $K^+$, $Ca^{2+}$, and $Mg^{2+}$, and available silicate concentration were lower or close to the optimal values, but the mean concentrations of available phosphorus were exceeded the range of optimal value, $80{\sim}120mg\;kg^{-1}$, in many paddy fields. In particular, The concentrations of available phosphorus in the paddy fields of local valley and fans, alluvial plains, and fluvio-marine plains were mostly declined. However, in diluvial terrace areas, the phosphorus concentrations unexpectedly increased; furthermore, they were significantly higher than those in other topographic areas. The mean concentrations of 0.1 M HCl-extractable heavy metals, Cd, Cr, Pb, Cu, Ni, and Zn, in the paddy fields were slightly and gradually declined during the study years, but the Pb concentrations were not statistically changed. In addition, the concentrations of heavy metals were widely ranged depending on the different sampling sites. Nevertheless, the concentrations of heavy metals were significantly lower than the levels of Soil Contamination Warning Standard (SCWS) for agricultural lands (1-region) presented in Soil Environment Conservation Law (SECL).