• Title/Summary/Keyword: Mg and A

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Varietal Difference in Plant Regeneration from Cotyledon Culture of Capsicum annuum L. (고추 자엽에서 식물체 재분화의 품종간 차이)

  • 오명규;이영만;박문수
    • Korean Journal of Plant Tissue Culture
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    • v.25 no.5
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    • pp.301-304
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    • 1998
  • Effects of genotype and culture medium on plant regeneration from cotyledon segments of red pepper(Capsicum annuum L.) was investigated. Among combinations of IAA(0.25 and 0.50 mg/L) and zeatin(2.0 and 4.0 mg/L) added to MS medium, combination of 2.0 mg/L zeatin and 0.25 mg/L IAA was shown to be the best for shoot differentiation from cotyledon segments. Shoot regeneration from cotyledon explants took 9 to 25days, depending on genotypes and culture media. Early shooting was observed in Yeongyangjaelae, Putgochw, Karkovskij-A-35, Gris I-A-1 on MS medium containing 2.0 mg/L zeatin and 0.25 IAA mg/L. Percent of explants producing shoots, as also influenced by genotypes and culture media, were over 90% for 621, Yeongyangjaelae, Putgochw, Nikko jacksacgmulgochw, Ch-6-Num-216, and Kajenskij-A-35 when cultured on MS medum supplemented with 2.0 mg/L zeatin and 0.25 mg/L IAA and for Fresno chile, PI 169126, Kajenskij-A-35, jacksacgmulgochw, and PI 297438 on MS medium including 2.0 mg/L BA and 1.0 mg/L IAA.

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General Pharmacology of LB20304a, a New Quinolone Antibiotic (새로운 퀴놀론계 항생제 LB20304a의 일반약리작용)

  • 김희진;오정인;이창호
    • Biomolecules & Therapeutics
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    • v.4 no.2
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    • pp.184-189
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    • 1996
  • General pharmacological studies of LB20304a (a mesylate salt form of a new quinolone antibiotic LB20304 following oral administration of 300 mg/kg and 1000 mg/kg, almost maximum tolerance dose in mice and rat, respectively, were performed in terms of effects on general behaviour, central nervous system, gastrointestinal system, and blood coagulation system in mice and rats. With regards to general behaviour of mice, at oral dose of 300 mg/kg, LB20304a reduced muscle tone and locomotor activity. In terms of CNS, at oral treatment of 300 mg/kg, LB20304a showed some analgesic effects in mice, and oral dose of 1000 mg/kg caused drop in normal body temperature of rat, while it enhanced the pentylenetetrazole-induced clonic convulsion to tonic convulsion and/or death in mice at the doses of unto 300 mg/kg. In addition, LB20304a increased hexobarbital-induced sleeping time two and three times in mice at oral doses of 20 mg/kg and 300 mg/kg, respectively. Rota-rod and traction test in mice were not influenced by the dose of 300 mg/kg and 200 mg/kg, respectively. LB20304a reduced gastric secretion of rat at dose of 1000 mg/kg, and increased intestinal motility of mice at dose of 300 mg/kg. In rats, blood coagulation index, such as PT (prothrombin time) and aPTT (activated partial thromboplastin time) were not affected by the treatment of upto 1000 mg/kg of LB 20304a.

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A Dry-patterned Cu(Mg) Alloy Film as a Gate Electrode in a Thin Film Transistor Liquid Crystal Displays (TFT- LCDs) (TFT-LCDs 게이트 전극에 적용한 Cu(Mg) 합금 박막의 건식식각)

  • Yang Heejung;Lee Jaegab
    • Korean Journal of Materials Research
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    • v.14 no.1
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    • pp.46-51
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    • 2004
  • The annealing of a Cu(4.5at.% Mg)/$SiO_2$/Si structure in ambient $O_2$, at 10 mTorr, and $300-500^{\circ}C$, allows for the outdiffusion of the Mg to the Cu surface, forming a thin MgO (15 nm) layer on the surface. The surface MgO layer was patterned, and successfully served as a hard mask, for the subsequent dry etching of the underlying Mg-depleted Cu films using an $O_2$ plasma and hexafluoroacetylacetone [H(hfac)] chemistry. The resultant MgO/Cu structure, with a taper slope of about $30^{\circ}C$ shows the feasibility of the dry etching of Cu(Mg) alloy films using a surface MgO mask scheme. A dry-etched Cu(4.5at.% Mg) gate a-Si:H TFT has a field effect mobility of 0.86 $\textrm{cm}^2$/Vs, a subthreshold swing of 1.08 V/dec, and a threshold voltage of 5.7 V. A novel process for the dry etching of Cu(Mg) alloy films, which eliminates the use of a hard mask, such as Ti, and results in a reduction in the process steps is reported for the first time in this work.

Antioxidant and Physiological Activities of Coriolus versicolor Fruit Body Crude Extracts (운지버섯(Coriolus versicolor) 자실체 조 추출물의 항산화 활성 및 생리활성 연구)

  • Choi, Byeong Yong;Lee, Hyung H.
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.8
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    • pp.415-422
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    • 2016
  • In this research, the total polyphenol and flavonoid contents in the hot water extract (HE) and methanol extract (ME) of the Coriolus versicolor fruiting body and their partial bioactivities were investigated from March, 2015 to February, 2016. For the analysis of the data, the software used was SPSS 2.0. The results indicate that the total polyphenol content in the HE (129.60 mg/dl) was 85,8 mg/dl higher than that in the ME (43.80 mg/dl). The total flavonoid content in the HE (30.50 mg/dl) was 9.5 mg/dl higher than that in the ME (20.90 mg/dl). The DPPH scavenging activities of the HE and ME at a concentration of 3 mg/ml were 41.03% and 16.36% higher than those at a concentration of 1 mg/ml. The tyrosinase inhibitory activities of the HE and ME at a concentration of 3 mg/ml were 8.29% and 10.32% higher than those at a concentration of 1 mg/ml. The elastase inhibitory activities of the HE and ME at a concentration of 3 mg/ml were 3.12% and 21.53% higher than those at a concentration of 1 mg/ml. The collagenase inhibitory activities of the HE and ME at a concentration of 3 mg/ml were 5.44% and 4.07% higher than those at a concentration of 1 mg/ml. In conclusion, these two kinds of extracts are judged to be useful as skin wrinkle relaxants, due to their anti-oxidative and bioactive functions.

Effects of the size of Mg powder on the formation of MgB2 and the superconducting properties

  • Kim, D.N.;Jun, B.H.;Park, S.D.;Kim, C.J.;Park, H.W.
    • Progress in Superconductivity and Cryogenics
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    • v.18 no.4
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    • pp.9-14
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    • 2016
  • The effect of the size and shape of magnesium(Mg) powder on the formation of $MgB_2$ and the critical current density($J_{c,}$) of $MgB_2$ bulk was studied. As a precursor for the formation of $MgB_2$, Mg and $MgB_4$ powder, which was synthesized through the reaction of boron (B) with Mg powders, was used. $MgB_4$ was mixed with Mg powders of various sizes, pressed into pellets and heat-treated at $650^{\circ}C-750^{\circ}C$ in flowing argon gas. The XRD analysis of the heat-treated $MgB_2$ samples showed that the volume fraction of $MgB_2$ was the highest as 92.74 % when spherical Mg powder with an average size of $25.7{\mu}m$ was used, whereas the volume fraction was the lowest as 79.64 % when plate-like Mg powder with a size of $34.1{\mu}m$ was used. The superconducting transition temperature ($T_c$) of $MgB_2$ was not sensitive to the characteristics of the Mg powders used. All of the prepared $MgB_2$ samples showed a high $T_c$ of 38.3 K and a small superconducting transition width of 0.2 K-0.5 K. $J_c$ (5 K and 1 T) of $MgB_2$ was the highest as $3.93{\times}10^4A/cm^2$ when spherical Mg powder with a size of $25.7{\mu}m$ was used, whereas $J_c$ was the lowest as $2.18{\times}10^4A/cm^2$when plate-like Mg powder with a size of $34.1{\mu}m$ was used. The relationship between the $J_c$ of $MgB_2$ and the characteristics of the Mg powders used was explained in terms of the volume fraction of $MgB_2$ and the apparent density of the $MgB_2$ pellets.

Factors affecting passivation of Cu(Mg) alloy film (Cu(Mg) alloy의 산화방지막 형성에 영향을 미치는 인자)

  • 조흥렬;조범석;이원희;이재갑
    • Journal of the Korean Vacuum Society
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    • v.9 no.2
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    • pp.144-149
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    • 2000
  • Variables affecting the passivation capability of Cu(Mg) alloy films, which were sputter deposited from a Cu (4.5 at. %) target, have been investigated. The results show that the passivation capability of a Cu(Mg) alloy film is a function of annealing temperature, $O_2$ pressure, and Mg content in the film. Increasing the annealing temperature up to $500^{\circ}C$ favors formation of a dense MgO layer on the surface which has a growth limited thickness of 150 $\AA$. Decreasing the $O_2$ pressure enhances the preferential oxidation of Mg over Cu. Furthermore, increasing the Mg content in the Cu(Mg) film promotes formation of a dense MgO layer. Vacuum pre-annealing was found to be very effective in segregating Mg to the surface, facilitating the passivation capability of the Cu(Mg) alloy film even when the Mg content is low. In the current study, self-aligned MgO layers with low resistivity and an effective passivation capability over the Cu surface, have been obtained by manipulating these factors when Cu(Mg) thin films are annealed.

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A study on Electrical and Diffusion Barrier Properties of MgO Formed on Surface as well as at the Interface Between Cu(Mg) Alloy and $SiO_2$ (Cu(Mg) alloy의 표면과 계면에서 형성된 MgO의 확산방지능력 및 표면에 형성된 MgO의 전기적 특성 연구)

  • Jo, Heung-Ryeol;Jo, Beom-Seok;Lee, Jae-Gap
    • Korean Journal of Materials Research
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    • v.10 no.2
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    • pp.160-165
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    • 2000
  • We have investigated the electrical and diffusion barrier properties of MgO produced on the surface of Cu (Mg) alloy. Also the diffusion barrier property of the interfacial MgO between Cu alloy and $SiO_2$ has been examined. The results show that the $150\;{\AA}$-MgO layer on the surface remains stable up to $700^{\circ}C$, preventing the interdiffusion of C Cu and Si in Si/MgO/Cu(Mg) structure. It also has the breakdown voltage of 4.5V and leakage current density of $10^{-7}A/\textrm{cm}^2/$. In addition, the combined structure of $Si_3N4(100{\AA})/MgO(100{\AA})$ increases the breakdown voltage up to lOV and reduces the leakage current density to $8{\tiems}10^{-7}A/\textrm{cm}^2$. Furthermore, the interfacial MgO formed by the chemical reac­t tion of Mg and $SiO_2$ reduces the diffusion of copper into $SiO_2$ substrate. Consequently, Cu(Mg) alloy can be applied as a g gate electrode in TFT /LCDs, reducing the process steps.

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Intracellular Mg2+ concentration dependent Mg2+ release in the hearts (심장에서 세포내 Mg2+ 농도 의존적 Mg2+ 유리)

  • Baek, Sung-soo;Kim, Shang-jin;Kim, Jln-shang
    • Korean Journal of Veterinary Research
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    • v.40 no.2
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    • pp.291-299
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    • 2000
  • Magnesium ($Mg^{2+}$) transport across the plasma membrane of cardiac myocytes appears to be under hormonal control. Repeated stimulations with adrenergic or histaminergic agonist produced a progressive decrease in $Mg^{2+}$ efflux from hearts. Thus we hypothesized that the $Mg^{2+}$ efflux may be resulted from a down-regulation of receptors or from a depletion of $Mg^{2+}$ from intracellular pool(s) in the hearts. In the present study, the regulation of $Mg^{2+}$ homeostasis by receptor stimulation was studied in perfused rat and guinea pig hearts. The successive short addition of norepinephrine (NE) to rat and guinea pig, and of histamine (HT) to perfused guinea pig hearts induced a progressive decrease in $Mg^{2+}$ efflux. These $Mg^{2+}$ effluxes were blocked by propranolol or ranitidine, respectively. These decrease in $Mg^{2+}$ efflux were inhibited by sodium cyanide (NaCN), which increases intracellular $Mg^{2+}$ ($[Mg^{2+}]_i$) levels. When NE (or HT) was added after HT (or NE), this efflux was also decreased in the guinea pig hearts. In the rat hearts and myocytes, HT did not stimulate $Mg^{2+}$ efflux. But NE produced a large $Mg^{2+}$ efflux after stimulation with HT. 8-(4-Chlorophenylthio)-adenosine cAMP (cAMP), like NE and HT, also induced a progressive decrease in $Mg^{2+}$ efflux in guinea pig hearts. This effect was inhibited by NaCN. These data provide evidence that the progressive decrease in receptor-stimulated $Mg^{2+}$ efflux is considered to be due to a decrease in $[Mg^{2+}]_i$ levels rather than receptor down-regulation.

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The effect of HRT variation on acidogenic fermentation with municipal primary sludge (1차 하수슬러지의 유기산발효에 미치는 HRT의 영향)

  • Kim, Hyeong-Seok;Song, Young-Chae;Sung, Nak-Chang
    • Journal of the Korea Organic Resources Recycling Association
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    • v.10 no.3
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    • pp.68-73
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    • 2002
  • Acidogenic fermentation of primary sludge was investigated for the solution to reduce the sewage sludge and develope external carbon source for BNR process. In a viewpoint to use existing anaerobic digestion tanks, we didn't change environmental factors such as reactor configuration, temperature, pH and investigate the variation of solubilization rates, acidification rates and environmental factors which affected by the variation of HRT. The average solubilization rates were 0.0309 and $0.0204mgSCOD_{prod.}/mgICOD_{inf.}$ at a HRT of 3 and 1.5 days, respectively. The average acidification rates were 0.0068mg HAc/mg $TCOD_{inf.}$ and 0.0652mg HAc/mg $VSS_{destroyed}$ at a HRT of 3day. At a HRT of 1.5 days the average acidification rates were 0.0060mg HAc/mg $TCOD_{inf.}$ and 0.0346mg HAc/mg $VSS_{destroyed}$. For the period of experiments alkalinity and pH were properly maintained without artificial adjusting.

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The analysis of Nutrients in Artemisia capillaris Thunberg (사철쑥 (Artemisia capillaris Thunberg)의 영양성분 분석)

  • Lee, Hyoung-Ja;Hwang, Eun-Hee;Yu, Hyeen-Hee;Song, In-Sang;Kim, Chang-Min;Kim, Myung-Chul;Hong, Jin-Hwan;Kim, Dong-Sul;Han, Sang-Bae;Kang, Kil-Jin;Lee, Eun-Ju;Chung, Hyung-Wook
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.31 no.3
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    • pp.361-366
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    • 2002
  • A. capillaris Thunberg is often used as a medicinal herb. This analysis on A. capillaris Thunberg, showing its natural ingredients and nutritive elements, is to provide a better understanding of its content and help find more various ways of use. The ingredients of A. capillaris Thunberg are as follows : 14.12% of crude protein, 4.80% of crude lipid, 2.30% of crude ash, 8.10% of crude fiber, and the rest of the ingredients are vitamins and minerals. Minerals are 3295.02 mg% of K, 2787.01 mg% of P, 1436.01 mg% of Ca, 172.32 mg% of Mg, 21.23 mg% of Fe, 18.02 mg% of Mn, 8.11 mg% of Na, 1.24 mg% of Cu, and 0.002 mg% of Sn, and vitamins are 18602.00 ug% of $\beta$-carotene and 5.82 mg% of ascorbic acid. Fatty acids in A. capillaris Thunberg are of 23.86% of oleic acids (C18:1), 46.67% of saturated fatty acids, 33.40% of monousaturated fatty acids, and 19.83% of polyunsaturated fatty acids. Oleic acid (C18:1) is the most abundant fatty acid in A. capillaris Thunberg. P/S is 0.24. A. capillaris Thunberg contains about 20 kinds of amino acid. The total amount of amino acids is 1345.29 mg%, which can be divided into 79.95% of amino acids and 13.11% of essential amino acids. This 79.95% of amino acids consist of proline, tyrosine, asparagines, glutamic acid, and valine with amount of 438.58mg%, 310.20mg%, 120.30mg%, 118.66mg%, and 88.02mg% respectively. The essential amino acid is 176.83mg%. It is shown that A. capillaris Thunberg contatins various nutrients such as minerals, vitamins, fatty acids, and amino acids, so A. capillaris Thunberg can be regarded as a highly nutritious food.