• Title/Summary/Keyword: Reaction region

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Optical Diagnostics of Nanopowder Processed in Liquid Plasmas

  • Bratescu, M.A.;Saito, N.;Takai, O.
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.02a
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    • pp.17-18
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    • 2011
  • Plasma in liquid phase has attracted great attention in the last few years by the wide domain of applications in material processing, decomposition of organic and inorganic chemical compounds and sterilization of water. The plasma in liquid is characterized by three main regions which interact each - other during the plasma operation: the liquid phase, which supply the plasma gas phase with various chemical compounds and ions, the plasma in the gas phase at atmospheric pressure and the interface between these two regions. The most complex region, but extremely interesting from the fundamental, chemical and physical processes which occur here, is the boundary between the liquid phase and the plasma gas phase. In our laboratory, plasma in liquid which behaves as a glow discharge type, is generated by using a bipolar pulsed power supply, with variable pulse width, in the range of 0.5~10 ${\mu}s$ and 10 to 30 kHz repetition rate. Plasma in water and other different solutions was characterized by electrical and optical measurements. Strong emissions of OH and H radicals dominate the optical spectra. Generally water with 500 ${\mu}S/cm$ conductivity has a breakdown voltage around 2 kV, depending on the pulse width and the repetition rate of the power supply. The characteristics of the plasma initiated in ultrapure water between pairs of different materials used for electrodes (W and Ta) were investigated by the time-resolved optical emission and the broad-band absorption spectroscopy. The deexcitation processes of the reactive species formed in the water plasma depend on the electrode material, but have been independent on the polarity of the applied voltage pulses. Recently, Coherent anti-Stokes Raman Spectroscopy method was employed to investigate the chemistry in the liquid phase and at the interface between the gas and the liquid phases of the solution plasma system. The use of the solution plasma allows rapid fabrication of the metal nanoparticles without being necessary the addition of different reducing agents, because plasma in the liquid phase provides a reaction field with a highly excited energy radicals. We successfully synthesized gold nanoparticles using a glow discharge in aqueous solution. Nanoparticles with an average size of less than 10 nm were obtained using chlorauric acid solutions as the metal source. Carbon/Pt hybrid nanostructures have been obtained by treating carbon balls, synthesized in a CVD chamber, with hexachloro- platinum acid in a solution plasma system. The solution plasma was successfully used to remove the template remained after the mesoporous silica synthesis. Surface functionalization of the carbon structures and the silica surface with different chemical groups and nanoparticles, was also performed by processing these materials in the liquid plasma.

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A Thermal Study of the Harmful Chemical Species of Charcoal and Their Transformation during Combustion (숯의 유해물질과 이들의 연소 중 상변화에 대한 열분석 연구)

  • Yoon, Hye-On;Kim, Ki-Hyun
    • Journal of the Mineralogical Society of Korea
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    • v.24 no.2
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    • pp.101-110
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    • 2011
  • Charcoal burning in the process of manufacture and ordinary use often release many constituent chemical species. As a result of open burning, the chemical composition as well as the physical properties of original material changes through the modification of surface properties of charcoal. Surface modification could be more responsible toward the outside elements for surface adsorption, it becomes easy to adsorb more toxic elements through surface adsorption. In this study, four kinds of commercially available charcoal were studied against the chemical and thermal stability along with the heavy metals and organic hazardous substances. Thermo gravimetric analysis (TGA) and differential scanning calorimetry, from room temperature to $400^{\circ}C$, were performed to study the weight loss and the changes in the behavior of those substances. According to TGA analysis, about 10% of weight loss was happened before $200^{\circ}C$. It was found that related weight loss of this temperature region may responsible to the gas phase organic matter. Natural charcoal, K1 and C1 show 15% of loss during the reaction heated to $400^{\circ}C$, while the artificial charcoal K2, C2 show the weight loss of about 20% was found. This is consistent with the main organic matter and VOC analysis results shown. Chemical composition based on the x-ray diffraction analysis was carried out. X-ray diffraction analysis reveals the existence of chemical additive in the forms of $Ba(NO_3)_2$, $BaCO_3$, and $NaNO_3$.

Effects of Mycelial Extract of Phellinus linteus on Ethanol-Induced Liver Injury in Rats (알코올성 간 손상에 대한 상황버섯 배양균사체 추출물의 효능)

  • Choi, Byung-Tae;Choi, Yung-Hyun;Gil, Young-Gi
    • Journal of Life Science
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    • v.16 no.6
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    • pp.978-983
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    • 2006
  • We investigated the anti-inflammatory effects of mycelial culture extract from Phellinus linteus (MCPL) for suppression in the process of ethanol-induced inflammation in rat liver. Levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were significantly increased in the serum of ethanol-treated rats compared to normal. However, the level of ALT was arrested markedly in ethanol-treated rats with MCPL compared to ethanol alone treated control ones. Severe histopathological changes of liver such as cloudy swelling, inflammatory cells infiltration, Kupffer cell reaction and focal necrosis were demonstrated in the rats challenged with ethanol compared with normal. Fewer scores of these changes were observed in MCPL-treated rat with recovered glycogen in centrolobular region of hepatic lobule. The Western analysis showed that the expression of inflammatory proteins such as cyclooxygenase (COX)-1, COX-2, inducible nitric oxide synthase (iNOS), tumor necrosis factor $(TNF)-{\alpha}$ were increased in the ethanol-treated rat. But decline of COX-2 and iNOS expression were observed in MCPL-treated rat. Immunohistochemical analysis showed that the expression of COX-2 and $TNF-{\alpha}$ tended to increase in ethanol-treated rat, but decrease of these reactions were induced by MCPL treatment. These results suggest that MCPL may act as a protective agent for alcohol-induced liver injury through a regulating inflammation-related proteins.

Plant Growth-Promoting Activity of Endophytic Fungi Isolated from the Roots of Native Plants in Dokdo Islands (독도 자생식물의 뿌리로부터 분리된 내생균의 식물생장촉진 활성)

  • You, Young-Hyun;Yoon, Hyeok-Jun;Woo, Ju-Ri;Seo, Yeong-Gyo;Kim, Mi-Ae;Choo, Yeon-Sik;Kim, Jong-Guk
    • Journal of Life Science
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    • v.21 no.11
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    • pp.1619-1624
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    • 2011
  • Endophytic fungal strains were isolated from the roots of six species plants in the Dokdo islands. Native plant samples, such as Artemisia japonica, Chenopodium album and Solanum nigrum were isolated from Dongdo, and those such as Cyrtomium falcatum, Dianthus longicalyx and Tetragonia tetragonoides were isolated from Seodo. In total, thirty two fungal strains were isolated from these native plants. To identify the fungal strains, polymerase chain reaction (PCR) amplification of internal transcribed spacer (ITS: containing ITS1, 5.8s and ITS2 region) regions was done with universal primers ITS1 and ITS4. Endophytic fungi of four species were isolated from A. japonica, eight species from C. album, three species from S. nigrum, three species from C. falcatum, three species from D. longicalyx and eleven species from T. tetragonoides. Culture filtrates (CF) of isolated endophytic fungi were used to treatwaito-c rice seedlings to test plant growth-promoting activity. As a result of bioassay, Ca-5-2-2 strain isolated from C. album expressed highest plant growth-promotion activity. Of all the endophytic fungi isolated, Penicillium sp., Fusarium sp. and Aspergillus sp. were the most abundantly distributed fungal strains in the six plants used in this study.

Effect of Antioxidants on the Thermostability of Red Pigment in Prickly Pear (선인장열매 적색색소의 열안정성에 대한 항산화제의 효과)

  • Kim, In-Hwan;Kim, Myung-Hee;Kim, Houng-Man;Kim, Young-Eun
    • Korean Journal of Food Science and Technology
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    • v.27 no.6
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    • pp.1013-1016
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    • 1995
  • The color stability of betacyanins and effects of antioxidants from Opuntia dillenii Haw were determined in the fruit juice at temperature up to $90^{\circ}C$. The absorption maxima of betacyanins occurred between 536 nm and 538 nm. When fruit juice was heated at $90^{\circ}C$ for various times, the red color gradually diminished and the absorption maxima slightly shifted toward uv region. The kinetic analysis of the data obtained indicated that the discoloration for betacyanins obeyed first order reaction pattern, when the thermal stability test was performed at $50{\sim}90^{\circ}C$. And the rate constant increased from $1.56{\times}10^{-3}/min\;to\;71.91{\times}10^{-3}/min$ with the half-life decreasing from 444.23 min to 9.64 min. The results also indicated that the thermal stability of pigment decreased with increasing temperature. The energy of activation was 10.94 kcal/mole for the pigment. N-propyl gallate, L-cysteine, and ascorbic acid were added to cactus fruit juice at concentrations of $0.01{\sim}0.3%$ at different temperatures. Npropyl gallate and L-cysteine had a little antioxidant effect on betacyanins stability at $50^{\circ}C\;and\;70^{\circ}C$, whereas ascorbic acid had a great antioxidant effect with the half-life value of 2 to 10 times to that of the control.

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Molecular characterization and expression of a disintegrin and metalloproteinase with thrombospondin motifs 8 in chicken

  • Lee, Ra Ham;Lee, Seokhyun;Kim, Yu Ra;Kim, Sung-Jo;Lee, Hak-Kyo;Song, Ki-Duk
    • Asian-Australasian Journal of Animal Sciences
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    • v.31 no.8
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    • pp.1366-1372
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    • 2018
  • Objective: A disintegrin and metallopeptidase with thrombospondin motifs type 8 (ADAMTS8) is crucial for diverse physiological processes, such as inflammation, tissue morphogenesis, and tumorigenesis. The chicken ADAMTS8 (chADAMTS8) gene was differentially expressed in the kidney following exposure to different calcium concentrations, suggesting a pathological role of this protein in metabolic diseases. We aimed to examine the molecular characteristics of chADAMTS8 and analyze the gene-expression differences in response to toll-like receptor 3 (TLR3) stimulation. Methods: The ADAMTS8 mRNA and amino acid sequences of various species (chicken, duck, cow, mouse, rat, human, chimpanzee, pig, and horse) were retrieved from the Ensembl database and subjected to bioinformatics analyses. Reverse-transcription polymerase chain reaction (RT-PCR) and quantitative PCR (qPCR) experiments were performed with various chicken tissues and the chicken fibroblast DF-1 cell line, which was stimulated with polyinosinic-polycytidylic acid (poly[I:C]; a TLR3 ligand). Results: The chADAMTS8 gene was predicted to contain three thrombospondin type 1 (TSP1) domains, whose amino acid sequences shared homology among the different species, whereas sequences outside the TSP1 domains (especially the amino-terminal region) were very dif­ferent. Phylogenetic analysis revealed that chADAMTS8 is evolutionarily clustered in the same clade with that of the duck. chADAMTS8 mRNA was broadly expressed in chicken tissues, and the expression was significantly up-regulated in the DF-1 cells in response to poly(I:C) stimulation (p<0.05). These results showed that chADAMTS8 may be a target gene for TLR3 signaling. Conclusion: In this report, the genetic information of chADAMTS8 gene, its expression in chicken tissues, and chicken DF-1 cells under the stimulation of TLR3 were shown. The result suggests that chADAMTS8 expression may be induced by viral infection and correlated with TLR3-mediated signaling pathway. Further study of the function of chADAMTS8 during TLR3-dependent inflammation (which represents RNA viral infection) is needed and it will also be important to examine the molecular mechanisms during different regulation, depending on innate immune receptor activation.

Correlation analyses of CpG island methylation of cluster of differentiation 4 protein with gene expression and T lymphocyte subpopulation traits

  • Zhao, Xueyan;Wang, Yanping;Guo, Jianfeng;Wang, Jiying
    • Asian-Australasian Journal of Animal Sciences
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    • v.31 no.8
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    • pp.1141-1149
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    • 2018
  • Objective: Cluster of differentiation 4 protein (CD4) gene is an important immune related gene which plays a significant role in T cell development and host resistance during viral infection. Methods: In order to unravel the relationship of CpG island methylation level of CD4 gene with its gene expression and T lymphocyte subpopulation traits, we used one typical Chinese indigenous breed (Dapulian, DP) and one commercial breed (Landrace), then predicted the CpG island of CD4 gene, determined the methylation status of CpG sites by bisulfite sequencing polymerase chain reaction (BSP), and carried out the correlation analyses of methylation frequencies of CpG sites with mRNA expression and T lymphocyte subpopulation traits. Results: There was one CpG island predicted in the upstream -2 kb region and exon one of porcine CD4 gene, which located 333 bp upstream from the start site of gene and contained nine CpG sites. The correlation analysis results indicated that the methylation frequency of CpG_2 significantly correlated with CD4 mRNA expression in the DP and Landrace combined population, though it did not reach significance level in DP and Landrace separately. Additionally, 15 potential binding transcription factors (TFs) were predicted within the CpG island, and one of them (Jumonji) contained CpG_2 site, suggesting that it may influence the CD4 gene expression through the potential binding TFs. We also found methylation frequency of CpG_2 negatively correlated with T lymphocyte subpopulation traits CD4+CD8-CD3-, CD4-CD8+CD3- and CD4+/CD8+, and positively correlated with CD4-CD8+CD3+ and CD4+CD8+CD3+ (for all correlation, p<0.01) in DP and Landrace combined population. Thus, the CpG_2 was a critical methylation site for porcine CD4 gene expression and T lymphocyte subpopulation traits. Conclusion: We speculated that increased methylation frequency of CpG_2 may lead to the decreased expression of CD4, which may have some kind of influence on T lymphocyte subpopulation traits and the immunity of DP population.

Impacts of Internet Blog Information on the Economic Landscape of Real Space: Case Study of Bookchon (지역에 대한 인터넷 블로그 정보와 지역 경제경관의 변화 - 서울 북촌을 사례로 -)

  • Lee, Keum-Sook;Seo, Wee-Yeun;Chae, Ji-Min
    • Journal of the Economic Geographical Society of Korea
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    • v.15 no.2
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    • pp.206-227
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    • 2012
  • This study investigates the interaction mechanisms and processes between cyber space and real space. In particular, we analyze the relationships between changes on the economic landscape of the Bookchon region and the information supply and demand for this area on the Internet Blogs. In order to obtain the behavioral data about how people get information for Bookchon area and the reaction afterward, we perform questionnaire survey. The results of analysis reveal that there are significant connection between real space and cyber space, Internet Blog in particular. Internet Blog is the major media obtaining information about Bookchon area for major portion of people. Most people visit Bookchon after searching informations about it via Internet Blog. In particular, young generations who possess better capability to treat social media. At the same time, female, student, and office workers show these attitudes very strongly. We introduce a conceptual model for the interaction processes between cyber space and real space based on the survey data analysis, and propose a simple theoretical model for the dynamics of the total number of visitors about specific place with the experience of cyber space visit.

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Association of the COMT Gene Polymorphism with the Risk of PCOS in Korean Women (한국인 여성에서 다낭성난소증후군의 발생 위험도와 Catechol-O-Methyltransferase 유전자 다형성과의 관련성에 관한 연구)

  • Lee, Ji Young;Cha, Yun Jeong;Hur, Seung Eun;Kwon, Han Sung;Lee, Sun-Joo;Sohn, In Sook;Kim, Soo Nyung;Seung, Yon A;Chung, Hye Won
    • Clinical and Experimental Reproductive Medicine
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    • v.33 no.2
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    • pp.97-104
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    • 2006
  • Objective: To investigate whether polymorphism of Catechol-O-methyltransferase(COMT) gene is associated with the risk of polycystic ovary syndrome (PCOS) in Korean women. Methods: One hundred and thirty-six PCOS patients and eighty four controls were enrolled. Blood samples were collected from the patients diagnosed according to the 2003 revised criteria of the Rotterdam ESHRE/ASRM-sponsored PCOS consensus workshop group. Age matched women with regular menstruation from same geographic region were recruited as control subject. Polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) of PCR products were done to determine all individuals' genotype. Results: In women with $COMT^{LL}$ genotype, there was decreased PCOS risk and this difference was statistically significant (OR 0.24, 95% CI 0.11~0.51). Conclusion: The results suggest that the $COMT^{LL}$ genetic polymorphism might be associated with PCOS risk in Korean women.

Preparation and Characterization of Small Intestine Submucosa Powder Impregnated Poly(L-lactide) Scaffolds: The Application for Tissue Engineered Bone and Cartilage

  • Khang, Gilson;Rhee, John M.;Shin, Philkyung;Kim, In Young;Lee, Bong;Lee, Sang Jin;Lee, Young Moo;Lee, Hai Bang;Lee, Ilwoo
    • Macromolecular Research
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    • v.10 no.3
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    • pp.158-167
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    • 2002
  • In order to endow with new bioactive functionality from small intestine submucosa (SIS) powder as natural source to poly (L-lactide) (PLA) and poly (lactide-co-glycolide) (PLGA) synthetic biodegradable polymer, porous SIS/PLA and SIS/PLGA as natural/synthetic composite scaffolds were prepared by means of the solvent casting/salt leaching methods for the possibility of the application of tissue engineered bone and cartilage. A uniform distribution of good interconnected pores from the surface to core region was observed the pore size of 40~500 ${\mu}{\textrm}{m}$ independent with SIS amount using the solvent casting/salt leaching method. Porosities, specific pore areas as well as pore size distribution also were almost same. After the fabrication of SIS/PLA hybrid scaffolds, the wetting properties was greatly enhanced resulting in more uniform cell seeding and distribution. Five groups as PGA non-woven mesh without glutaraldehyde (GA) treatment, PLA scaffold without or with GA treatment, and SIS/PLA (Code No.3 ; 1 : 12 of salt content, (0.4 : 1 of SIS content, and 144 ${\mu}{\textrm}{m}$ of median pore size) without or with GA treatment were implanted into the back of nude mouse to observe the effect of SIS on the induction of cells proliferation by hematoxylin and eosin, and von Kossa staining for 8 weeks. It was observed that the effect of SIS/PLA scaffolds with GA treatment on bone induction are stronger than PLA scaffolds, that is to say, in the order of PLA/SIS scaffolds with GA treatment > PLA/SIS scaffolds without GA treatment > PGA nonwoven > PLA scaffolds only with GA treatment = PLA scaffolds only without GA treatment for the osteoinduction activity. The possible explanations are (1) many kinds of secreted, circulating, and extracellular matrix-bound growth factors from SIS to significantly affect critical processes of tissue development and differentiation, (2) the exposure of SIS to GA resulted in significantly calcification, and (3) peri-implant fibrosis due to covalent bonding between collagen molecule by crosslinking reaction. In conclusion, it seems that SIS plays an important role for bone induction in SIS/PLA scaffolds for the application of tissue engineering area.