• Title/Summary/Keyword: $H_2O $

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Role of Reactive Oxygen Species in the Adipogenesis of Adipose-derived Stem Cells (지방유래줄기세포의 지방분화과정에서 활성산소가 미치는 영향)

  • Chang, Hak;Min, Kyung-Hee;Park, Young-In;Kim, Yo-Han;Minn, Kyung-Won
    • Archives of Plastic Surgery
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    • v.38 no.2
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    • pp.131-134
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    • 2011
  • Purpose: Stem cells continue to receive research attention in the clinical fields, and adipose-derived stem cells (ADSCs) have been shown to be a good source raw material. Many plastic surgeons are researching the ADSC adipogenesis with a view of conducting clinical trials, and many attempts have been made to identify the factors that promote the adipogenesis of ADSCs, but comparatively few correlation studies have been undertaken to explore the relation between reactive oxygen species (ROS) and the ADSC adipogenesis. We undertook this study is to investigate the effects of ROS on ADSC adipogenesis. Methods: ADSCs were isolated and cultured from abdominal adipose tissue, and cultured in different media; 1) DMEM(control), 2) adipogenesis induction culture medium, 3) adipogenesis induction culture medium with ROS ($20{\mu}M/50{\mu}M\;H_2O_2$), 4) adipogenesis induction culture medium containing ROS ($20{\mu}M/50{\mu}M\;H_2O_2$) and antioxidant ($10{\mu}M/20{\mu}M$ Deferoxamine). We compared adipogenesis in these different media by taking absorbance measurements after Oil-Red O staining every 5 days. Results: After culturing for 20 days, significant differences were observed between these various culture groups. Absorbance results showed significantly more adipogenesis had occurred in media containing adipogenesis induction culture medium and $H_2O_2$ (in a $H_2O_2$ dose-dependently manner) than in media containing adipogenesis induction culture medium and no $H_2O_2$ (p<0.001). Furthermore, in media containing adipogenesis induction culture medium, $H_2O_2$, and antioxidant, absorbance results were significantly lower than in adipogenesis induction culture medium and $H_2O_2$ (p<0.001). Conclusion: These findings suggest that ROS promote the adipogenesis of ADSCs. We suggests that ROS could be used in the adipose tissue engineering to improve fat cell differentiation and implantable fat tissue organization.

Effects of Liming and Nitrogen Sources on the Yield and Quality of Burley Tobacco II. Effects of Chemical Constituents of tobacco leaves (석회의 질소원이 버어리종 담배의 수량과 품질에 미치는 영향 II. 잎담배의 화학성분에 미치는 영향)

  • 김상범;한철수;김용규
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.32 no.4
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    • pp.379-385
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    • 1987
  • A field experiment was conducted to find out the effects of liming (soil pH) and sources of N on the chemical constituents of soil and leaf lamina of burley tobacco. Treatments consisted of liming (nonliming, liming to soil pH 5.5 and 6.5) as the main plot and N sources[compound fertilizer of containing 3.9% $NH_4-N$ and 6.1% $NH_2-N,\;NaNO_3,\;(NH_2)_2CO\;and\;(NH_4)_2SO_4$]as the sub-plot. The soil pH was high in $NaNO_2$ plot, while low in $(NH_4)_2SO_4$. But the differences of Ca concentration in top soil among N sources were not detected. The $NO_3-N$ concentration in top soil was high in high limed and $NaNO_3$ plot. The $NO_3-N$ content of leaf (lamina) at 75 days after transplanting was high in $NaNO_3$ plot and CaO con-tent of leaf at 45 days after transplanting was high in high limed plot. But neither liming nor N source had effect on the contents of total nitrogen, $P_2-O_{5}\;and\;K_2O$ of leaf during growing season. There was no significant differences in total alkaloid and total nitrogen contents of cured leaf (lamina) to liming and N source. But when the source of N was $NaNO_3$, the content of total alkaloid was increased by adding lime. When the source of N was $(NH_4$)_2SO_4$, the content of $K_2O$ in cured leaf was high while CaO was low. But neither liming nor N source had effect on the contents of $P_2-O_{5}$ and MgO in cured leaf.

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N,N'-Dimethylethylenediamine-N,N'-di-α-butyric Acid Cobalt(III) Complexes Utilizing Oxidation of Sulfur of S-Methyl-L-cysteine

  • Kim, Hyun-Jin;Youm, Kyoung-Tae;Yang, Jung-Sung;Jun, Moo-Jin
    • Bulletin of the Korean Chemical Society
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    • v.23 no.6
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    • pp.851-856
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    • 2002
  • The Reaction of S-methyl-S-cysteine(L-Smc) with racemic $s-cis-[Co(demba)Cl_2]-1$ (Hydmedba = $NN'-dimethylethylenediamine-NN'-di-\alpha-butyric$, acid) yields ${\Delta}$-s-cis-[Co(dmedba)(L-Smc)] 2 with N, O-chelation. Oxidation of sulfur of 2 with $H_2O_2$ in a 1 : 1 mole ratio gives ${\Delta}$-s-cis[Co(dmedba)(L-S(O)mc)] 3 having an uncoordinated sulfenate group. Oxidation of sulfur of L-Sm with $H_2O_2in$ a 1: 1 mole ratio produces S-methyl-L-cysteinesulfenate (L-S(O)me) 5. Direct reaction of 1 with 5 in basic medium gives an N.O-chelated ${\Delta}$s-cis[Co(dmedba)(L-S(O)mc)-N.O], which turmed out be same as obtained by oxidation of 2, while an N, S-chelated ${\Delta}$-s-cis-[Co(dmedba)(S-S(O)mc)-N,O] complex 4 is obtained in acidic medium from the reaction of 1 with 5. This is one of the rare $[$Co^{III}$(N_2O_2-type$ ligand)(amino acid)] type complex preparations, where the reaction conditions determine which mode of N, O and N, S caelation modes is favored.

Purification and Some Properties of Peroxidase from the Fruit Malus sieboldii (Regel) Rehder (아그배 Peroxidase의 정제 및 특성)

  • Yang, Hee-Cheon;Son, Hee-Suk;Shim, Kyu-Kwang;Oh, Chan-Ho;Choi, Dong-Seong
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.21 no.1
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    • pp.84-90
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    • 1992
  • Peroxidase in the fruit of Malus sieboldii (Regel) Rehder was partially purified by DEAE-cellulose column chromatography and Ultro-AcA 54 gel filtration. The optimum pH of peroxidase was 4.5 and optimum temperature was $80^{\circ}C$. The enzyme was stable at pH 5.0 and below $30^{\circ}C$, and inactivated by heat treatment at $80^{\circ}C$ for 15min. In the presence of 30mM $H_{2}O_2$ Km value on o-phenylenediamine as substrate was 1.65mM, and in the presence of 10mM o-phenylenediamine Km value on $H_{2}O_2$ was 7.97mM. L-Ascorbic acid and sodium L-ascorbate greatly inhibited the enzyme activity and among several metal ions $Mn^{2+}$ only increased the activity at 5mM.

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Phase Separation Characteristics via Bunsen Reaction in Sulfur-Iodine Thermochemical Hydrogen Production Process (SI 열화학 수소 제조 공정에서 분젠 반응을 통한 상 분리 특성)

  • Lee, Kwang-Jin;Kim, Young-Ho;Park, Chu-Sik;Bae, Ki-Kwang
    • Journal of Hydrogen and New Energy
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    • v.19 no.5
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    • pp.386-393
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    • 2008
  • The Sulfur-iodine(SI) thermochemical cycle is one of the most promising methods for massive hydrogen production. For the purpose of continuous operation of SI cycle, phase separation characteristics into two liquid phases ($H_2SO_4$-rich phase and $HI_x$-rich phase) were directly investigated via Bunsen reaction. The experiments for Bunsen reaction were carried out in the temperature range, from 298 to 333 K, and in the $I_2/H_2O$ molar ratio of $0.109{\sim}0.297$ under a continuous flow of $SO_2$ gas. As the results, solubility of $SO_2$, decreased with increasing the temperature, had considerable influence on the global composition in the Bunsen reaction system. The amounts of impurity in each phase(HI and $I_2$ in $H_2SO_4$-rich phase and $H_2SO_4$ in $HI_x$-rich phase) were decreased with increasing $H_2SO_4$ molar ratio and temperature. To control the amounts of impurity in $HI_x$-rich phase, temperature is a factor more important than $I_2/H2_O$ molar ratio. On the other hand, the affinity between $HI_x$ and $H_2O$ was increased with increasing $I_2/H2_O$molar ratio.

Numerical Simulation of The Pressure-Flow Control Characteristics of Shunt Valves Used to Treat Patients with Hydrocephalus (수두층 치료용 션트밸브의 압력-유량 제어특성 수치해석)

  • 장종윤;이종선;서창민
    • Journal of Biomedical Engineering Research
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    • v.22 no.5
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    • pp.403-412
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    • 2001
  • The Present study analyzed the pressure-flow characteristics of a Korean shunt valve. Changes in the characteristic currie depending on the design parameters were also investigated. The Korean shunt valve used in the present study was constant pressure type and our analyses were validated through experiments. We applied fluid-structure interaction to solve the flow dynamic Problem because the small diaphragm in the valve was made from flexible silicone elastomers. Considering the material nonlinearity of the hyper-elastic material. the Mooney-Rivlin approximation was employed. The results of the numerical analyses were close to the experimental results The major Pressure drop was observed to happen in the small diaphragm. The slope of the pressure-flow characteristic curve was computed to be 0.37mm$H_2O$.hr/cc, which was similar to the average value of commercial shunt valves. 0.40mm$H_2O$.hr/cc. Therefore. our valves analyzed in the Present study showed a Proper Pressure control characteristics of the constant pressure type shunt valves. The opening pressure could be controlled by adjusting the amount of predeflection of the valve diaphragm. In order to obtain opening pressures of 25mm$H_2O$ and 80mm$H_2O$, respectively, and the required predeflection was found to be 10.2$\mu$m and 35.3$\mu$m. The flow orifice size was found to be within 10$\mu$m during valve operation Therefore, Precision design and manufacturing techniques are necessary for successful operations of the shunt valve. The study indicated the amount of predeflection as well as the magnitude of corner rounding of the diaphragm edge are important design parameters to influence the slope of the pressure-flow characteristic curve.

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The Oxidation of Functionally Gradient NiCrAlY/YSZ Coatings

  • Park, K.B.;Park, H.S.;Kim, H.J.;Lee, D.B.
    • Journal of Surface Science and Engineering
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    • v.34 no.5
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    • pp.499-502
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    • 2001
  • Functionally gradient NiCrAlY/$ZrO_2$-$Y_2$$O_3$ and NiCrAlY/$ZrO_2$- $CeO_2$-$Y_2$$O_3$ coatings were prepared by APS. The as-sprayed microstructure consisted of metal-rich and ceramic-rich regions, between which $Al_2$$O_3$-rich layers existed owing to the oxidation during APS. During oxidation between 900 and $1100^{\circ}C$ in air, the pre-existing $Al_2$$O_3$-rich scales grew, due mainly to the preferential reaction of Al with inwardly transporting oxygen along the heterogeneous phase boundaries. As the amount of ceramics in the coating increased, the oxidation resistance increased.

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Synthesis of Cr-doped Y2O3-Al2O3 Red Pigments and their Application (Cr-doped Y2O3-Al2O3계 붉은 안료의 합성과 적용)

  • Shin, Kyung-Hyun;Lee, Byung-Ha
    • Journal of the Korean Ceramic Society
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    • v.45 no.8
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    • pp.453-458
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    • 2008
  • New inorganic red pigments based on Cr-doped $Y_2O_3$ and $Al_2O_3$ were synthesized by solid state method and characterization of their pigments were characterized by using XRD, FT-IR, SEM and UV-Vis spectrophotometer. The single perovskite phase revealed at $1450^{\circ}C{\sim}1550^{\circ}C$ for 6 h due to using mineralizers. The color of pigment powders resulted out various red-shades depending on the compositions of used materials and temperatures. Glazed tiles painted with pigment powders showed red color in oxidation and reduction firing. The best red colour was obtained when the $Cr_2O_3$ was used 0.04 mole at $1450^{\circ}C$ for 6 h.

Effect of the Calcination Conditions for the Synthesized $BaTiO_3$ Powder and the Sintered PTC Ceramics by Oxalic Acid Method (Oxalic Acid법으로 합성한 $BaTiO_3$ 분말과 소결한 PTC 세라믹스에 대한 하소조건의 효과)

  • 이미재;황선아;최병현
    • Journal of the Korean Ceramic Society
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    • v.31 no.11
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    • pp.1378-1386
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    • 1994
  • The characteristic of calcined BaTiO3 powder and sintered PTC ceramics was investigated varing with calcination temperature and time of BaTiO(C2O4)2.4H2O synthesized from BaCl2.2H2O, TiCl4, oxalic acid and ethanol by oxalic acid method. When the particle size was less than 0.1 ${\mu}{\textrm}{m}$ by controlling calcination temperature and time, the resistance at room temperature was measured very high (above M{{{{ OMEGA }}). However, when the calcined particle sizes ranged from 0.2 to 0.3 ${\mu}{\textrm}{m}$, the resistance was 100 {{{{ OMEGA }} (After sintering, the grain size was 10~30 ${\mu}{\textrm}{m}$ homogeneously with the addition of dopant in sintering, the resistivity, resistance, $\alpha$ value and jumped to were 110{{{{ OMEGA }}.cm, 24$^{\circ}C$/% and 106{{{{ OMEGA }}, respectively.

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