• Title/Summary/Keyword: Half Life

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Effect of Copper on the Regulation of Ferroportin-1 Gene Expression (구리가 Ferroportin-1 유전자 발현 조절에 미치는 영향)

  • Park, Bo-Yoen;Chung, Ja-Yong
    • Journal of Nutrition and Health
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    • v.42 no.5
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    • pp.434-441
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    • 2009
  • Ferroportin-1 (FPN) is a transporter protein that is known to mediate iron export from macrophages. The purpose of this study was to investigate the effect of copper on the regulation of FPN gene expression in J774 mouse macrophage cells. J774 cells were treated with various concentrations of $CuSO_4$ and RT-PCR analyses were performed to measure the steady-state levels of mRNAs for FPN and divalent metal transporter 1 (DMT1, an iron importer). Copper treatment significantly increased FPN mRNAs in a dose-dependent manner, but didn't change the levels of DMT1 mRNA. Experiments with transcriptional inhibitor actinomycin D (0.5 ${\mu}g$/mL) revealed that copper treatment did not affect the half-life of FPN mRNAs in J774 cells. On the other hand, results from luciferase reporter assays showed that copper directly stimulated the promoter activity of FPN. In summary, our data showed copper induced FPN mRNA of macrophages via a transcriptional rather than post-transcriptional mechanisms.

Ozone-Enhanced Remediation of Diesel-Contaminated Soil (II): A Column Study (Ozone에 의한 유류오염토양 복원 연구 (II) : 토양 컬럼상에서의 오존 산화)

  • Choi, Heechul;Heechul;Lim, Hyung-Nam;Kim, Kwang-Soo
    • Journal of Korean Society of Environmental Engineers
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    • v.22 no.10
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    • pp.1825-1832
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    • 2000
  • Column experiments were conducted by using soil columns, to investigate feasibility and efficiency of in-situ ozone enhanced remediation for diesel-contaminated soil. The injection of gaseous ozone into soil column revealed the enhanced decomposition of ozone due to the catalytic reaction between ozone and metal (e.g., Fe, Mn etc.) oxides as evidenced by as much as 25 times shorter half-life of ozone in a sand packed column than in a glass beads packed column. Substantial retardation in the transport of and the consumption of ozone were observed in the diesel contaminated field soil and sand packed columns. After 16 hrs ozonation, 80% of the initial mass of diesel (as diesel range organic) concentration of $800{\pm}50mg/kg$, was removed under the conditions of the flow rate of 50mL/min and $6mg-O_3/min$. Whereas, less than 30% of diesel was removed in the case of air injection. Analysis of the residual TPH(total petroleum hydrocarbon) and selected 8 aliphatics of diesel compounds in the inlet and the outlet of the column confirmed that diesel nonselectively reacted with ozone and then shifted to lower carbon numbered molecules. Water content also was found to be an important parameter in employing ozone to the hydrocarbon-contaminated soil.

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Removal Characteristics of Synthetic Musk Compounds in Water by Ozone Treatment (오존처리에 의한 수중의 인공 사향물질 제거특성)

  • Seo, Chang-Dong;Son, Hee-Jong;Yoom, Hoon-Sik;Lee, Sang-Won;Ryu, Dong-Chun
    • Journal of Korean Society of Environmental Engineers
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    • v.34 no.2
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    • pp.73-78
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    • 2012
  • In this study, three different synthetic musk compounds (SMCs) in the Nakdong river water (raw water) and rapid sand filtered water were treated by $O_3$ process. The experimental results showed that the removal efficiency of musk ketone (MK) was lower than removal efficiency of AHTN (7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronaphthalene) and HHCB (1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta[c]-2-benzopyran) for both the raw water and the rapid sand filtered water. And in general, the removal efficiencies of three SMCs in the raw water were lower than that in the sand filtered water. Under the $O_3$ dose of 0.5~10.0 mg/L, the removal rate constants (k) of three SMCs for the raw and sand filtered waters increased rapidly with the increased $O_3$ dose. In the case of drinking water treatment plants (DWTPs) which were selected pre- and post-$O_3$ processes (located in the downstream of Nakdong River), operation conditions of pre- and post-$O_3$ process were $0.5{\sim}2.0mg{\cdot}O_3/L$ (2~4 min) and $0.5{\sim}2.5mg{\cdot}O_3/L$ (6~8 min). Therefore, $O_3$ doses and contact times of same conditions with above were very difficult to remove SMCs in DWTPs.

Early Childhood Teachers' Perception for Fairy Tale Appearance Using Background Music (배경음악을 활용한 동화감상에 대한 유아교사의 인식)

  • Park, Seon-Young;Hong, Soon-Ock
    • The Journal of the Korea Contents Association
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    • v.18 no.3
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    • pp.342-353
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    • 2018
  • The purpose of this study was to investigate the awareness of early childhood teachers for the development of early childhood education programs using background music. The subjects of this study were 272 early childhood teachers of kindergartens in Busan and Kyungnam provinces. The data were collected through questionnaires on the awareness of children's appreciation of fairy tales using background music. The collected data were analyzed by frequency and percentage using SPSS 18.0 program. The results of this study are as follows: First, the number of early childhood teachers who had experience of performing fairy tales using background music were less than half of them. Secondly, the purpose of appreciation of fairy tales using background music was to develop rich emotions. In order to understand the systematic knowledge and concept of background music, it was necessary to supply background music in various life styles. Third, development of a fairy tale appreciation program using background music was generally required. Third, development of a fairy tale appreciation program using background music was generally required. Fourth, a fairy tale appreciation program using background music is appropriate for the large group activity time of 10~20 minutes one or two times a week and it was necessary to have a concatenated structure of pre-activities, introduction methods, questioning techniques in development, finishing methods, evaluation methods, and extension activity methods.

Pharmacokinetics of Recombinant Human Epidermal Growth Factor (DWP401) in Rats (재조합 인간 상피세포성장인자(DWP401)의 흰쥐에서의 약물동태)

  • Chung, Joo-Young;Koh, Yeo-Wook;Nam, Kwon-Ho;Cho, Jae-Youl;Park, Seung-Kook;Yu, Young-Ho;Kim, Jae-Hwan;Han, Kun;Park, Myung-Hwan;Shim, Chang-Koo
    • YAKHAK HOEJI
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    • v.41 no.3
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    • pp.328-334
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    • 1997
  • Pharmacokinetics of DWP401, a recombinant human epidermal growth factor (rhEGF), was studied using radioimmunoassay (RIA) and $^{125}I$-DWP401 in rats. When DWP401 was adm inistered i.v. at doses of 50 and 500 mcg/kg, the plasma DWP401 disappeared biiexponentially with terminal half life of 4.7 and 92.8 min. The $C_{max}$ and $T_{max}$ after s.c. administration of ti at doses of 50 and 500 ${\mu}g$/kg were determined to be 23.6 and 17.5 ng/ml at 50 ${\mu}g$/kg, and 261.4 ng/ml and 36.8 min, respectively. Both the total urinary and biliary recoveries of intact DWP401 2343 very low (<0.4%), probably due to its extensive degradation in the body. the concentration ratio of DWP401 between the organ and plasma decreased especially in the liver and kidney as the dose and time after the dose increased. For example, the liver/plasma and kidney/plasma concentration ratio of DWP401 at 2.5 min after i.v. doses of 50 ${\mu}g$/kg were comparable and much larger than unity. But, the ratio at 2.5 min after i.v. doses of 500${\mu}g$/kg was much larger in the kidney that in than in the liver. These results suggest that the systemic administration of DWP401 might be subject to rapid and extensive clearance from circulation within several hour after main distrbution to liver and kidney.

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Pharmacokinetic Study of YH1885 (I): Absorption, Distribution and Excretion of $^{14)C-YH1885$ in Rats (YH1885의 체내동태(제1보):흰쥐에서 $^{14)C-YH1885$의 단회투여시 흡수, 조직분포 및 배설)

  • Ahn, Byung-Nak;Fujio, Naoki;Kusumoto, Naotoshi;Abe, Yoshifumi;Odomi, Masaaki;Lee, Jong-Wook
    • YAKHAK HOEJI
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    • v.41 no.3
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    • pp.335-344
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    • 1997
  • The absorption, distribution and excretion of $^{14}C$ labeled YH1885 {5,6-Dimethyl-2(4-fluorophenylamino)-4-(1-methyl-1,2,3,4-tetrahydroisoquinolin-2-yl)pyrimidine hydroc hloride), a new proton pumpinhibitor, were investigated in rats after a single administration of $^{14}C$-YH1885. 1. After intravenous administration of 5mg/kg, the blood level of radioactivity declined in a biphasic fashion with the mean terminal elimination half-life of 12.4hr. 2. After oral administration of 20mg/kg, the maximum blood level of radioactirity was reached at 4.0hr in female rats. The blood level of radioactivity-time profiles in male and female rats were similar, and the absorptionof $^{14}C$-YH1885 was not affected by food. 3. Appproximately 89% and 1% of radioactivity of the total dose were excreted in feces and urine, respectively. 4. Biliary excretion of radioactivity was 47.9% of the dose. Enterohepatic circulation of radioactivity was 49.6%. 5. Radioactivity was excreted maily into feces via bile. 6. The concentration of radioactivity in most tissues reached the peak level at 4.0hr after dosing, and then declined. Autoradiograms of male rats showed that the radioactivity levlels in the fat, harder's gland, liver and G-Itract were higher than those in the other tissues and the elimination of radioactivity from fat and liver was slow. 7. Autoradiograms of a pregnant rat showed that radioactivity was transferred to mammary gland, placenta and fetus. The radioactivity level in the mammary gland was higher than that in the blood.

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Simple Material Budget Modeling for a River-Type Reservoir (하천형 저수지의 단순 물질수지 모델링)

  • Yoon, Seong-Kyu;Kong, Dong-Soo;Bae, Wookeun
    • Journal of Korean Society on Water Environment
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    • v.26 no.3
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    • pp.420-431
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    • 2010
  • Simple material budget models were developed to predict the dry season water quality for a river-type reservoir in Paldang, Republic of Korea. Of specific interest were the total phosphorus (TP), chlorophyll ${\alpha}$ (Chl. ${\alpha}$), 5-day biochemical oxygen demand (BOD), and chemical oxygen demand (COD). The models fit quite well with field data collected for 20 years and have enabled the identification of the origins of organic materials in the reservoir. The critical hydraulic load that determines the usability of phosphorus for algal production appeared to be about $1.5m\;d^{-1}$. When a hydraulic load was smaller than the critical value, the concentrations of $Chl.{\alpha}$, COD, and BOD in the reservoir water became sensitive to internal algal reactions such as growth, degradation, and settling. In spite of the recent intensive efforts for organic pollutant removal from major point sources by central and local governments, the water quality in the reservoir had not been improved. Instead, the concentration of COD increased. The model analysis indicated that this finding could be attributed to the continuing increase of the algal production in the reservoir and the allochthonous load from non-point sources. In particular, the concentrations of COD and BOD of algal origin during 2000~2007, each of which is comprised of approximately one half of the total, were approximately 2.5 times higher than those observed during 1988~1994 and approximately 1.3 times higher than those between 1995~1999. The results of this study suggested that it is necessary to reduce the algal bloom so as to improve the water quality of the reservoir.

Adsorption and Movement of Fenoxaprop-P-ethyl in Soils (토양중 fenoxaprop-P-ethyl의 흡착성 및 이동성)

  • Han, Soo-Gon;Ahn, Byung-Koo;Moon, Young-Hee
    • Korean Journal of Weed Science
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    • v.18 no.4
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    • pp.325-332
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    • 1998
  • This study was carried out to investigate the adsorption and the movement of herbicide fenoxaprop-P-ethyl in the silty clay soil(SiC) and the sandy loam soil(SL). Fifteen percent of the added herbicide was adsorbed within 30 min after shaking, and a quasi-equilibrium was reached after 8 to 14 h. The time required for 50% adsorption was 15.8 h in the SiC and 19.3 h in the SL. The equilibrium adsorption isotherm was followed by the Freundlich equation and the Kd was 3.86 in the SiC and 2.32 in the SL. The herbicide in the soil columns flooded with 3 cm water depth and eluted at 0.8 cm/day was leached to 6 cm and 8 cm depth at 7 and 21 days after the treatment, respectively. However, the movement was widened with increased amount of leaching water. The herbicide in the field soils was moved up to 6 cm and 8 cm depth at 14 and 56 days after the treatment, respectively. However, the large amount of the applied herbicide was distributed in 0~2 cm profile in all of the soils examined. Half-life of the chemical in soils was shorter than 7 days and the time to 90% degradation was about 4 weeks. The results indicate that the herbicide has relatively small mobility and short persistence.

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Toxicokinetics of rifapentine in beagle dogs (Beagle dog에 있어서 rifapentine의 독성동태연구)

  • Shin, Ho-chul;Lee, Hye-suk;Cha, Shin-woo;Han, Sang-seop;Roh, Jung-ku;Kim, Jin-suk;Lee, Won-chang
    • Korean Journal of Veterinary Research
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    • v.35 no.4
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    • pp.815-822
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    • 1995
  • The toxicokinetics of rifapentine was studied after an oral administration to beagle dogs. High-performance liquid chromatography(HPLC) using column-switching technique was performed to determine the serum concentrations of rifapentine. The pharmacokinetic profiles of rifapentine were analysed using one-compartment open model. Following a single oral administration of 10mg/kg, pharmacokinetic parameters were determined as follows: maximum serum concentration($C_{max}$), $28.90{\mu}g/ml$; maximum concentration time($T_{max}$), 3.7hr; elimination half-life($t_{1/2}$, 4.7hr; area under the curve(AUC), $339.0{\mu}g{\cdot}hr/ml$; volume of disiribution/bioavailability (Vd/F), 0.21 l/kg; lag time, 24min; absorption rate constant($k_a$), $0.445hr^{-1}$; elimination rate constant($k_{el}$), $0.148hr^{-1}$. After 6 month multiple oral doses of 10mg/kg/day, parameters were as follows: $C_{max}$, $34.40{\mu}g/ml$; $T_{max}$, 2.6hr; $t_{1/2}$, 6.7hr; AUC, $391.3{\mu}g{\cdot}hr/ml$; Vd/F, 0.291/kg; $k_a$, $0.976hr^{-1}$; $k_{el}$, $0.104hr^{-1}$. The consistant kinetic parameters after a single and multiple oral administration show that there was no accumulation of rifapentine after 6 month oral administration. We also simulated the concentration of rifapentine after oral multiple administration of 10 and 50mg/kg/ day, based on the parameters obtained form the single administration. The measured serum concentrations of rifapentine were well fitted to the simulated results. The simulated results show that rifapentine readily reaches to steady-state after about 3 doses and the steady-state serum concentrations($C_{ss}$) are fluctuated in between $2.2{\sim}25.2{\mu}g/ml$, and $10.6{\sim}125.2{\mu}g/ml$ at the doses of 10 and 50mg/kg/day, respectively.

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Studies on Degradation of Butachlor and Nitrofen in Different Soil Conditions (토양중(土壤中) Butachlor 와 Nitrofen의 분해(分解)에 관(關)한 연구(硏究))

  • Oh, Byung-Youl;Jeong, Young-Ho;Lee, Byung-Moo
    • Applied Biological Chemistry
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    • v.24 no.2
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    • pp.112-119
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    • 1981
  • The persistence of preemergence herbicides, butachlor [2-chloro-2,6-diethyl-N(butoxymethyl) acetanilide] and nitrofen(2,4-dichlorophenyl-4-nitrophenyl ether), at 10 ppm level in different soil conditions amended with organic matter and lime was studied under flooded and field moisture capacity. The microbial breakdown played a major role in the dissipation of the herbicides in soil. Nitrofen degradation in flooded soil was greatly accelerated, while it was slowed down in field moisture capacity as compared with butachlor. Increased amendment of rice straw to the soil shortened the half-life of butachlor under flooded condition, however it prolonged that of butachlor when the amendment was exceeded over 1% on dry weight basis. Liming the soil stimulated decomposition of the herbicides in the soil systems, which ap pears to be pH independent.

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