• Title/Summary/Keyword: Release effect

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Analysis of Dispersion Characteristics and Toxic Effect in the Small-Scale Continuous Release of Chlorine Gas (염소가스의 소규모 연속누출에서 분산특성 및 독성영향 해석)

  • Kim Tae-Ok;Jang Seo-Il;Lee Young-Jae
    • Journal of the Korean Institute of Gas
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    • v.8 no.2 s.23
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    • pp.8-14
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    • 2004
  • This study analyzed dispersion characteristics and toxic effect in the small-scale continuous release of chlorine gas. We found that the Gaussian model using the Briggs' dispersion coefficient and the effective release height was better predicting experiments than the BM model. From chlorine concentrations calculated by Gaussian model, simulation results showed that the dispersion of chlorine was more affected by atmospheric stability and wind speed than release rate and that the toxic effect of chlorine gas was similar to the effect of parameters on chlorine dispersion. From effected areas with toxic criteria, damaged areas could be estimated to protect human.

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Glucose Modulation of Release of Endogenous Catecholamines from Hypothalamic Fragments in Vitro (시상하부 조각에서 내재성 카테콜아민의 분비에 대한 포도당의 조절작용)

  • Jung, Jun-Sub;Hwang, Hyung-Sik;Wie, Myung-Bok;Song, Dong-Keun;Kim, Yong-Sik;Kim, Yung-Hi
    • The Korean Journal of Pharmacology
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    • v.29 no.2
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    • pp.183-188
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    • 1993
  • Effects of glucose on the catecholamine release from the hypothalamic fragments in vitro were studied. Basal release of catecholamines was inversely related to the concentrations $(5{\sim}30\;mM)$ of glucose in the incubation medium. Glucose did not affect the 30 mM $K{^+}-stimulated$ release of catecholamine. In the presence of tetrodotoxin $(10\;{\mu}M)$, the inhibitory effect of glucose on the basal release of catecholamines was largely persisted, but the inhibitory effect of 30 mM glucose on dopamine release was largerly blocked. In the presence of both tetrodotoxin $(10\;{\mu}M)$ and desipramine $(3\;{\mu}M)$, glucose failed to affect the basal catecholamine release. The results suggest that glucose modulates the catecholamine release through a direct action on the catecholaminergic nerve terminals, as well as through a trans-synaptical action. The glucose-modulation of the catecholamine release may explain, at least in part, the diabetes-induced changes in the hypothalamic catecholamine metabolism.

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The Role of Adenosine Receptor on Norepinephrine Release from Ischemic-Induced Rat Hippocampus (허혈이 유발된 흰쥐 해마에서 Norepinephrine 유리에 미치는 Adenosine 수용체의 역할)

  • Chung, Jong-Hoon;Choi, Bong-Kyu
    • The Korean Journal of Pharmacology
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    • v.32 no.2
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    • pp.139-150
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    • 1996
  • The effects of adenosine analogues on the electrically-evoked norepinephrine(NE) release and the influence of ischemia on the effects were studied in the rat hippocampus. Slices from the rat hippocampus were equilibrated with $0.1{\mu}M$ $[^3H]-norepinephrine$ and the release of the labelled product, $[^3H]-NE$, was evoked by electrical stimulation(3 Hz, 2 ms, 5 $VCm^{-1}$ and rectangular pulses for 90 sec), and the influence of various agents on the evoked tritium-outflow was investigated. Ischemia(15min with 95% $N_2$ +5% $CO_2$) increased both the basal and evoked NE release. These increases were abolished by addition of glucose into the superfused medium, and they were significantly inhibited either by $0.3\;{\mu}M$ tetrodotoxin pretreatment or by removing $Ca^{++}$ in the medium. MK-801$(1{sim}10\;{\mu}M)$, a specific NMDA receptor antagonist, and glibenclamide $(1\;{\mu}M)$, a $K^+-channel$ inhibitor, neither alter the evoked NE release nor affected the Ischemia-Induced increases in NE release. However, polymyxin B(0.03 mg), a specific protein kinase C inhibitor, inhibited the effect of ischemia on the evoked NE release. Adenosine and $N^6-cyclopentyladenosine$ decreased the NE release in a dose-dependent manner in ischemic condition, though the magnitude of inhibition was far less than those in normal (normoxic) condition. Also the treatment with $5{\mu}M$ DPCPX, a potent $A_1-adenosine$ receptor antagonist did not affect the ischemia-effect. These results suggest that the evoked-NE release is potentiated by ischemia, and this process being most probably mediated by protein kinase C, and that the decrease of NE release mediated through $A_1-adenosine$ receptor is significantly inhibited in ischemic state.

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Inhibititory Effect of Water- or petroleum Ether-extract from Red Ginseng on Serotonin Release from Human Platelets (Comparative Study Between 6-year and 4-year Old of Red Ginseng) (사람 혈소판으로부터 serotonin 방출반응 대한 홍삼의 물 추출물 및 petroleum ether 추출물의 억제 효과)

  • 박화진;고성룡
    • Journal of Ginseng Research
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    • v.22 no.2
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    • pp.140-146
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    • 1998
  • It was founded that an X-compound is contained in extracts from the root of old red ginseng (6RG) compared with that from the root of 4-year old red ginseng(4RG). Both water extract and petroleum ether extract (PEII) from 6RG or 4RG inhibited the release of [$^{3}H$]-serotonin induced by platelet activating factor (PAF; 40 ng/ml). Water extract and PEll from 6RG Inhibited potently PAF-induced [$^{3}H$]-serotonin release compared with those from 4RG. X-compound out of both water extract and PEll from 6RG inhibited the release of [$^{3}H$]-serotonin inducted by collagen (100 $\mu\textrm{g}$/ml) or thrombin(20 U/ml). X-compound had a synergistic effect with water extract from 4RG on collagen-and thrombin-induced [3H] -serotonin release out of human platelets. The concentration(IC50) of X-compound that require to inhibit 50% of [$^{3}H$]-serotonin-release was 3.25 $\mu\textrm{g}$/ml, and it is inferred that maximum concentration of X-compound that inhibits the release of [$^{3}H$]-serotonin is 10 $\mu\textrm{g}$/ml. Because thrombosis is resulted mainly from the irreversible aggregations which are intimately related with the serotonin release and migraine is also caused when serotonin is released, it is inferred that water extract, PEII and X-compound from 6RG have antithrombosis and antimigrainous functions by inhibiting the release of serotonin from human platelets.

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Effect of Protein Kinase C on Norepinephrine Release in the Rat Hippocampus (흰쥐 해마에서 Norepinephrine 유리에 미치는 Protein Kinase C 의 영향)

  • Kim, Do-Kyung;Lee, Young-Soo;Choi, Bong-Kyu
    • The Korean Journal of Pharmacology
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    • v.31 no.2
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    • pp.145-152
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    • 1995
  • The effects and interactions of $4{\beta}-phorbol$ 12,13-dibutyrate(PDB) and polymyxin B(PMB) with adenosine on the electrically-evoked norepinephrine (NE) release were studied in the rat hippocampus. Slices from the rat hippocampus were equilibrated with $^3H-noradrenaline$ and the release of the labelled product, $^3H-NE$, which evoked by electrical stimulation$(3\;Hz,\;2\;ms,\;5\;VCm^{-1},\;rectangular\;pulses)$ was measured. PDB$(0.3{\sim}10\;{\mu}M)$, a selective protein kinase C(PKC) activator, increased the evoked NE release in a dose related fashion while increasing the basal rate of release. And the effects of $1\;{\mu}M$ PDB were significantly inhibited by $0.3\;{\mu}M$ tetrodotoxin(TTX) pretreatment or $Ca^{++}-free$ medium. $PMB(0.03{\sim}1\;mg)$, a specific PKC inhibitor, decreased the NE release in a dose dependent manner while increasing the basal rate of release. Adenosine $(1{\sim}10\;{\mu}M)$ decreased the NE release without changing the basal rate of release, and this effect was significantly inhibited by 8-cyclopentyl-1,3-dipropylxanthine$(2\;{\mu}M)$, a selective $A_1-receptor$ antagonist, treatment. Also, adenosine effects were significantly inhibited by PDB-and PMB-pretreatment. These results suggest that the PKC plays a role in the NE release in the rat hippocampus and might be participated in a post-receptor mechanism of the $A_1-adenosine$ receptor.

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Effect of Controlled Release Fertilizer on the Growth and Flowering of Oncidium 'Sweet Sugar' (완효성비료 시비가 온시디움 생육과 개화에 미치는 영향)

  • Kim, Si Dong;Lee, Hee Doo;Kim, Ju Hyoung;Kim, Tae Jung
    • FLOWER RESEARCH JOURNAL
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    • v.17 no.4
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    • pp.246-250
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    • 2009
  • This study was conducted to determine the effect of controlled-release fertilizer on growth of Oncidium. Leaf and pseudobulb length increased with controlled-release fertilizer from 2 g to 3 g treatment compared to hyponex and controlled-release fertilizer I g treatment, while leaf width and number of leaf was not significant among treatments. Plant weight increased with controlled-release fertilizer from 2 g to 3 g treatment compared to hyponex and controlled-release fertilizer I g treatment. Flowering date(bloomed October early) did not show significant difference among treatments. The number of flowers showed the most in controlled-release fertilizer 3 g treatment as 62.4 ea/plant, but was not different significantly among treatments. Flower stem length and width were also non-significant among treatments. Branching numbers increased in the controlled-release fertilizer 2 g and 3 g treatments. Mineral elements of shoot increased from 2 g to 3 g treatment rather than the controlled-release fertilizer 1g treatment. Especially, K content was higher compared to N and P content. Therefore, appropriate controlled-release fertilizer amount for Oncidium was recommended as 2 g.

Evaluation of the Dam Release Effect on Water Quality using Time Series Models (시계열 모형의 적용을 통한 댐 방류의 수질개선 효과 검토)

  • Kim, Sangdan;Yoo, Chulsang
    • Journal of Korean Society on Water Environment
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    • v.20 no.6
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    • pp.685-691
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    • 2004
  • Water quality forecasting with long term flow is important for management and operation of river environment. However, it is difficult to set up and operate a physical model for water quality forecasting due to large uncertainty in the data required for model setting. Therefore, relatively simpler stochastic approaches are adopted for this problem. In this study we try several multivariate time series models such as ARMAX models for the possible substitute for water quality forecasting. Those models are applied to the BOD and COD levels at Noryangin station, Han river, and also evaluated the effect of release from Paldang dam on them. Monthly BOD and COD data from 1985 to 1991 (7 years) are used for model building and another two year data for model testing. As a result of the study, the effect of improvement on water quality is much more effective combining with the water quality improvement of dam release than considering only increment of dam release in the downstream Han river.

The study on the anti-allergic effect of Fagopyrum esculentum Moench(Me-mil) Extract. (메밀(蕎麥) 抽出物의 抗알레르기 反應에 對한 實驗的 硏究)

  • Jung, Ji-Young;Roh, Seok-Sun
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.15 no.1
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    • pp.31-49
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    • 2002
  • This Experimental study was done to research effects of Fagopyrum esculentum Moench(Me-mil) Extract on the anti-allergic effects. The results were obtained as follows : 1. All concentrations of Fagopyrum esculentum Moench Extract(Flours and seeds) inhibit histamine release under the vascular permeability response to intracutanenous injection. The result is proportion to concentration. But, rutin can't get considerable result. 2. All concentrations of Fagopyrum esculentum Moench Extract inhibit histamine release under the vascular permeability response to intraperitoneal injection of SD Rat in comparison with Diphenhydramine which is typical anti-histamine drug. 3. All concentrations of Fagopyrum esculentum Moench Extract inhibit histamine release under the vascular permeability response to per-oral during the three or five days. 4. In the result of quantification of histamine induced Compound $\frac{48}{80}$, Flours and seeds of Fagopyrum esculentum Moench Extract inhibit histamine release. 5. Among the fracination of Fagopyrum esculentum Moench Extract, $CHCl_3$ fraction inhibit histamine release effectively. 6. In the result of genetic manifestative inhibition about the Human mast cell treated PMA and A23187, Fagopyrum esculentum Moench Extract effect in the IL-4 and TNF-${\alpha}$ except IL-5. According to the above results, it is suggested that Fagopyrum esculentum Moench(Me-mil) Extract has anti-allergic effect.

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Release of Nifedipine from Poly(ethylene oxide) Tablets (폴리에칠렌 옥사이드 정제로부터 니페디핀의 방출양상)

  • Hong, Sung-In;Hur, Young-Lim;Oh, Seaung-Youl
    • Journal of Pharmaceutical Investigation
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    • v.30 no.3
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    • pp.207-211
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    • 2000
  • The objective of this work is to investigate the effect of molecular weight of poly(ethylene oxide) (PEO) and release medium on the release of nifedipine (NP) from PEO tablets containing NP and to get some mechanistic insights into the release of NP. The tablets containing NP were prepared by direct compression, using a flat-faced punch and die. The molecular weights of PEOs used were 200K, 900K, 2000K and 7,000K. The release kinetics were studied for 24 hours in aqueous ethanol solution, using a dissolution tester at $36.5^{\circ}C$ and 100 rpm. Drug release rate increased, as the concentration of ethanol in the dissolution medium increased, due to the increased solubility of NP. As the molecular weight of PEO increased, release rate decreased, due to the slower swelling and dissolution of PEO. The power values obtained by fitting data to the power law expression $(M_t/M_{\infty}=kt^n)$ indicated that, at low ethanol concentration, the release of NP is governed by anomalous diffusion. However, as the ethanol concentration increases, diffusional release becomes to prevail over anomalous or zero-order release. Overall, these results provided some insights into the release of NP from PEO tablet.

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A Study on the Melanin Synthesis Inhibition and Whitening Effect of Schizandrae Fructus (오미자(五味子)의 멜라닌 생성 억제와 미백효과에 관한 연구)

  • Doo, In-Sun;Lim, Kyu-Sang;Hwang, Chung-Yeon;Park, Min-Cheol;Kim, Nam-Kwen
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.20 no.3
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    • pp.51-62
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    • 2007
  • Objective : The aim of this study is to assess the effect of Schizandrae Fructus on melanin synthesis inhibition and whitening effect. Methods : We assessed inhibitory effects of Schizandrae Fructus on melanin-release from B16F10, on melanin production in B16F10, on mushroom tyrosinase activity in vitro, on tyrosinase activity in B16F10 and effect of Schizandrae Fructus on the expression tyrosinase, TRP-1, TRP-2, PKA, ERK-1 ERK-2, AKT-1, MITF in B16F10. Results and Conclusion : 1. Schizandrae Fructus inhibited melanin-release, melanin production in B16F10. 2. Schizandrae Fructus inhibited tyrosinase activity in vitro and in B16F10. 3. Schizandrae Fructus suppressed the expression of tyrosinase, TRP-1, TRP-2, PKA, ERK-2 in B16F10.

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