• Title/Summary/Keyword: R202C

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Automation of Glutamic Acid Fermentation (글루탐산 발효공정의 자동화)

  • Park, S.H.;Hong, K.T.;You, S.J.;Lee, J.H.;Bae, J.C.
    • Korean Journal of Food Science and Technology
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    • v.15 no.2
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    • pp.202-204
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    • 1983
  • A strategy for the automation of glutamic acid fermentation has been developed by the use of $CO_2$ analyzer together with a controller. It was found that a linear relationship existed between growth and $CO_2$ level in the exit gas. Therefore penicillin addition at an appropriate biomass concentration to excrete glutamate could be achieved automatically. In addition, an automatic batch feeding method (fed-batch culture) provided a means of overcoming substrate inhibition effects on growth and glutamic acid production in batch culture, thereby increasing productivity and product yield.

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The Isolation and Antioxidative Effects of Vitexin from Acer palmatum

  • Kim Jin Hwa;Lee Bum Chun;Kim Jin Hui;Sim Gwan Sub;Lee Dong Hwan;Lee Kyung Eun;Yun Yeo Pyo;Pyo Hyeong Bae
    • Archives of Pharmacal Research
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    • v.28 no.2
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    • pp.195-202
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    • 2005
  • Free radicals and reactive oxygen species (ROS) caused by UV exposure or other environmental factors are critical players in cellular damage and aging. In order to develop a new antiphotoaging agent, this work focused on the antioxidant effects of the extract of tinged autumnal leaves of Acer palmatum. One compound was isolated from an ethyl acetate soluble fraction of the A. palmatum extract using silica gel column chromatography. The chemical structure was identified as apigenin-8-C-beta-D-glucopyranoside, more commonly known as vitexin, by spectral analysis including LC-MS, FT-IR, UV, $^{1}H-$, and $^{13}C-NMR$. The biological activities of vitexin were investigated for the potential application of its anti-aging effects in the cosmetic field. Vitexin inhibited superoxide radicals by about $70\%$ at a concentration of $100\;{\mu}g/mL$ and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals by about $60\%$ at a concentration of $100\;{\mu}g/mL$. Intracellular ROS scavenging activity was indicated by increases in dichlorofluorescein (DCF) fluorescence upon exposure to UVB $20\;mJ/cm^2$ in cultured human dermal fibroblasts (HDFs) after the treatment of vitexin. The results show that oxidation of 5-(6-)chloromethyl-2',7'-dichlo-rodihydrofluorescein diacetate ($CM-H_{2}DCFDA$) is inhibited by vitexin effectively and that vitexin has a potent free radical scavenging activity in UVB-irradiated HDFs. In ROS imaging using a confocal microscope we visualized DCF fluorescence in HDFs directly. In conclusion, our findings suggest that vitexin can be effectively used for the prevention of UV-induced adverse skin reactions such as free radical production and skin cell damage.

Process optimization for biodiesel production from indigenous non-edible Prunus armeniaca oil

  • Singh, Deepak;Kumar, Veerendra;Sandhu, S.S.;Sarma, A.K.
    • Advances in Energy Research
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    • v.4 no.3
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    • pp.189-202
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    • 2016
  • This work emphasized optimum production of biodiesel using non-edible Prunus armeniaca (Bitter Apricot) oil via transesterification collected from the high altitude areas of Himachal Pradesh, India. In this study the author produced biodiesel through the process of transesterification by using an alkali catalyst with alcohol (methanol and ethanol), under the varying molar ratio (1:6, 1:9, 1:12), variable catalyst percentage (1% and 2%) and temperature ($70^{\circ}C$, $75^{\circ}C$, $80^{\circ}C$, $85^{\circ}C$). Furthermore, a few strong base catalysts were used that includes sodium hydroxide, potassium hydroxide, sodium metal and freshly prepared sodium methoxide. After screening the catalyst, response surface methodology (RSM) in connection with the central composite design (CCD) was used to statistically evaluate and optimize the biodiesel production operation using NaOH as catalyst. It was found that the production of biodiesel achieved an optimum level biodiesel yield with 97.30% FAME conversion under the following reaction conditions: 1) Methanol/oil molar ratio: 1:6, 2) Reaction time: 3h, 3) Catalyst amount: NaOH 2 wt. %, and 4) Reaction temperature: $85^{\circ}C$. The experimental results showed that the optimum production and conversion of biodiesel through the process of transesterification could be achieved under an optimal set of reaction conditions. The biodiesel obtained showed appropriate fuel properties as specified in ASTM, BIS and En- standards.

Secretion of Bovine $\beta$-Casein by Saccharomyces cerevisiae

  • Chung, Kun-Sub;Rafael, F.R.;Oh, Sang-Suk;Richardson, T.
    • Journal of Microbiology and Biotechnology
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    • v.1 no.1
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    • pp.31-36
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    • 1991
  • Yeast expression plasmids containing an appropriate leader sequence and bovine $\beta$-casein cDNA were constructed to produce $\beta$-casein for the study of its functional characteristics. Two kinds of expression systems for $\beta$-casein were constructed using pCGYl444 as a precursor plasmid. This plasmid is a yeast-E. coli shuttle vector which contains the chelatin promoter. The plasmid pISB202 contains the invertase leader sequence and $\beta$-casein gene. The plasmid pDEB303 contains the original bovine $\beta$-casein leader sequence gene. These two plasmids were introduced into S. cerevisiae AB116 which is a strain deficient in the major yeast proteinases. Each clone was grown in minimal media for 24 h before induction by $CuSO_4$. The cells were thus grown under expression conditions. Both strains harbouring pISB202 and pDEB303 expressed bovine $\beta$-casein. The $\beta$-casein was detected using immunochemical staining after western blot. Secretion of $\beta$-casein was detected in the culture broth. The estimated amount of secreted $\beta$-casein was approximately 50 ${\MU}g$/l.

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Factors Influencing Cardiopulmonary Resuscitation Skills in Nursing Students (간호대학생의 기본심폐소생술 수행능력 관련 요인)

  • Sim, Hwan-Hui;Tae, Young Sook
    • The Journal of Korean Society for School & Community Health Education
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    • v.16 no.2
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    • pp.1-15
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    • 2015
  • Objectives: This study purposed to identify the factors influencing cardiopulmonary resuscitation(CPR) skills in nursing students. Methods: The research design was descriptive study. Data were collected through structured questionnaires. The participants of this study were 202 nursing students in B & U metropolitan city, and C city. Data were collected from November 15 to November 30, 2013. The data were analyzed using t-test, ANOVA, Scheffe's test, Pearson's correlation coefficients, and Multiple stepwise regression with SPSS WIN v 20.0. Results: CPR knowledge(r=0.51, p<0.001), critical thinking disposition(r=0.43, p<0.001), CPR attitude(r=0.56, p<0.001). self efficacy(r=0.74, p<0.001), and CPR skills were significantly correlated with each other. Predictors of CPR skills were self efficacy, CPR knowledge, critical thinking disposition, grade, and CPR attitude. These variables explained 60% of CPR skills. Multiple regression analysis showed that most powerful factors influencing CPR skills among nursing students was self efficacy. Conclusions: Based on this study, it is required to develop nursing education program to improve self efficacy of nursing students for increasing CPR skills.

COMPARISON OF THE BIOMECHANICAL AND BIOSYNTHETIC BEHAVIOR OF NORMAL HUMAN FIBROBLASTS AND FIBROBLASTS ISSUE FROM A FOREHEAD WRINKLE

  • Jouandeaud, M.;Viennet, C.;Chadebec, P.;Bordes, S.;Closs, B.;Humbert, P.
    • Proceedings of the SCSK Conference
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    • 2003.09a
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    • pp.192-202
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    • 2003
  • The wrinkles correspond to the most obvious expression of skin ageing and are manifested by changes on the organization and dermal structure. In the extracellular matrix, decreased quantities of collagens and glycosaminoglycans as well as a deterioration of the fibrillary network is noted, result in a reduction of dermal thickness. In addition, the activity of the collagenases increases in contrast to the synthesis of collagen fibers. Nor are cells spared during the aging process. We thus studied and compared the contractile capacity as well as the synthesis capacity of normal human fibroblasts and human fibroblasts obtained from biopsies of forehead wrinkles. The capacity of the fibroblasts to be adhered to the collagen network and to maintain a three-dimensional structure of dermis was studied on a model of equivalent dermis. The metabolic activity was studied by evaluating the capacities of synthesis of collagen I, main component of dermis. Human fibroblasts resulting from the forehead wrinkle contract less the gel of collagen than the normal human fibroblasts and present an activity of biosynthesis of collagen I less important than normal human fibroblasts. These results show that fibroblasts with aging present a deceleration of their metabolic activity and lose their capacity of adhesion to collagen fibers thus limiting the possibility of organizing the dermal tissue. We investigated the potential of an active ingredient able to compensate for the reduction of the metabolic activity and to restore the contractile capacity of fibroblasts obtained from forehead wrinkles. This effect was compared with a reference molecule: the vitamin C.

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Study of 4-Nitroazoxybenzenes (Part Ⅰ) Separation of the Isomers of 4-Nitroazoxybenzenes and their Structure Study by U.V. Spectrophotometry (4-Nitroazoxybenzene 에 關한 硏究 (第1報) 4-Nitroazoxybenzene 의 $\{alpha}$- 및 ${\beta}$- 異性體의 分離와 U.V. Spectrophotometry에 의한 그 構造硏究)

  • Chi Sun Hahn;Byung Hi Yun;Hyuk Koo Lee
    • Journal of the Korean Chemical Society
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    • v.7 no.3
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    • pp.197-202
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    • 1963
  • The ${\alpha}-and\;{\beta}$-isomer of 4-nitroazoxybenzenes have been separated by liquid chromatography and their U.V. spectra were examined. The n${\to}{\pi}^{\ast}$ transition band of the compounds did not appear, likewise the cases of other compounds of the series. Transition band of the new isomer were as usual as those of other azoxy-compounds, whereas the ${\pi}{\to}{\pi}^{\ast}$ transition band of the other isomer which is reported in the literature shown peculier hypochromic shift and hypochromic effect. From the spectroscopic point of view it is very likely that the new isomer (m.p. $184-5^{\circ}C$) is ${\alpha}$-isomer and the other one (m.p. $152^{circ}C$) is ${\beta}$-isomer contrary to the literature.

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Three Crystal Structures of Dehydrated $Cd^{2+}$ and $Rb^+$ Exchanged Zeolite A, $Cd_xRb_{12-2x}-A,$ x=4.0, 5.0 and 5.95

  • Song, Yeong-Sim;Kim, Un-Sik;Kim, Yang;Kim, Duk-Soo
    • Bulletin of the Korean Chemical Society
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    • v.11 no.4
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    • pp.328-331
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    • 1990
  • Three crystal structures of dehydrated Cd(II) and Rb(I) exchanged zeolite A, $Cd_{4.0}Rb_{4.0}-A (a = 12.204(3) {\AA}), Cd_{5.0}Rb_{2.0}-A (a = 12.202(1) {\AA}),$ and $Cd_{5.95}Rb_{0.1}-A (a = 12.250(2) {\AA}),$ have been determined by single-crystal X-ray diffraction techniques. Their structures were solved and refined in the cubic space group Pm3m at $21(1)^{\circ}C.$ All crystals were ion exchanged in flowing streams of mixed $Cd(NO_3)_2·4H_2O$ and $RbNO_3$ aqueous solution with total concentration of 0.05 M. All crystals were dehydrated at ca. $450^{\circ}C$ and $2×10^{-6}$ Torr for 2 days. In all of these structures, $Cd^{2+}$ ions are found on threefold axes, each nearly at the center of a 6-oxygen ring. The first three $Rb^+$ ions per unit cell preferentially associate with 8-oxygen rings, and additional $Rb^+$ ions, if present, are found on threefold axes in the large cavity. The final $R_1$ and $R_2$ values for the three structures are 0.087 and 0.079, 0.059 and 0.067, and 0.079 and 0.095, respectively.

Crystal Structure of an Acetylene Sorption Complex of Vacuum Dehydrated Fully Cadmiumfiil-Exchanged Zeolite A (완전히 카드뮴 이온으로 교환된 제올라이트 A를 진공 탈수한 후 아세틸렌 기체로 흡착한 결정구조)

  • Koh, Kwang-Nak;Han, Young-Wook;Kim, Yang
    • Korean Journal of Crystallography
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    • v.2 no.1
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    • pp.17-22
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    • 1991
  • The crystal structure of an acetylene sorption complex of vacuum dehydrated fully Cda+ _exchanged zeolite A has been determined from three-dimensional X-ray diffraction data gathered by counter method. The structure was solved and refined in the cubic space group Pm3m at 294(1) K, a=12.202(3) A and Z=1. We crystal was prepared by dehydration at 723 K and 2.67×104 Pa for 2 days, followed by exposure to 1.60×104 Pa of acetylene gas at 298(1) K. All six Cd2+ions per unit cell are associated with 6-oxgen rings of the aluminosilicate framework. They are distributed over two distinguished threefold axes of unit cell; two of these Cd2+ ions are recessed 0.694 into the sodalite unit from (111) plane of three 0(3)'s and each approaches three framework oxides; the other four Cd2+ ions extend approximately 0.586A into the large cavity. The four Cd2+ ions are in a near tetrahedral environment, 2.220(9)A from·three framework oxide ions and 2.74(7) A from each carbon atom of an acetylene molecule(which is here counted as a monodentate ligand). Full matrix least squares refinement converged to the final error indices R1=0.093 and R2=0.105 using the 292 independent reflections for which I>3σ(I).

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