• Title/Summary/Keyword: 표현 산화

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Geochemical Equilibria and Kinetics of the Formation of Brown-Colored Suspended/Precipitated Matter in Groundwater: Suggestion to Proper Pumping and Turbidity Treatment Methods (지하수내 갈색 부유/침전 물질의 생성 반응에 관한 평형 및 반응속도론적 연구: 적정 양수 기법 및 탁도 제거 방안에 대한 제안)

  • 채기탁;윤성택;염승준;김남진;민중혁
    • Journal of the Korean Society of Groundwater Environment
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    • v.7 no.3
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    • pp.103-115
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    • 2000
  • The formation of brown-colored precipitates is one of the serious problems frequently encountered in the development and supply of groundwater in Korea, because by it the water exceeds the drinking water standard in terms of color. taste. turbidity and dissolved iron concentration and of often results in scaling problem within the water supplying system. In groundwaters from the Pajoo area, brown precipitates are typically formed in a few hours after pumping-out. In this paper we examine the process of the brown precipitates' formation using the equilibrium thermodynamic and kinetic approaches, in order to understand the origin and geochemical pathway of the generation of turbidity in groundwater. The results of this study are used to suggest not only the proper pumping technique to minimize the formation of precipitates but also the optimal design of water treatment methods to improve the water quality. The bed-rock groundwater in the Pajoo area belongs to the Ca-$HCO_3$type that was evolved through water/rock (gneiss) interaction. Based on SEM-EDS and XRD analyses, the precipitates are identified as an amorphous, Fe-bearing oxides or hydroxides. By the use of multi-step filtration with pore sizes of 6, 4, 1, 0.45 and 0.2 $\mu\textrm{m}$, the precipitates mostly fall in the colloidal size (1 to 0.45 $\mu\textrm{m}$) but are concentrated (about 81%) in the range of 1 to 6 $\mu\textrm{m}$in teams of mass (weight) distribution. Large amounts of dissolved iron were possibly originated from dissolution of clinochlore in cataclasite which contains high amounts of Fe (up to 3 wt.%). The calculation of saturation index (using a computer code PHREEQC), as well as the examination of pH-Eh stability relations, also indicate that the final precipitates are Fe-oxy-hydroxide that is formed by the change of water chemistry (mainly, oxidation) due to the exposure to oxygen during the pumping-out of Fe(II)-bearing, reduced groundwater. After pumping-out, the groundwater shows the progressive decreases of pH, DO and alkalinity with elapsed time. However, turbidity increases and then decreases with time. The decrease of dissolved Fe concentration as a function of elapsed time after pumping-out is expressed as a regression equation Fe(II)=10.l exp(-0.0009t). The oxidation reaction due to the influx of free oxygen during the pumping and storage of groundwater results in the formation of brown precipitates, which is dependent on time, $Po_2$and pH. In order to obtain drinkable water quality, therefore, the precipitates should be removed by filtering after the stepwise storage and aeration in tanks with sufficient volume for sufficient time. Particle size distribution data also suggest that step-wise filtration would be cost-effective. To minimize the scaling within wells, the continued (if possible) pumping within the optimum pumping rate is recommended because this technique will be most effective for minimizing the mixing between deep Fe(II)-rich water and shallow $O_2$-rich water. The simultaneous pumping of shallow $O_2$-rich water in different wells is also recommended.

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Susceptibility Weighted Image for Stem Cell Tracking in Rat Photothrombotic Infarction (흰쥐 광 혈전 뇌경색 모델에서 줄기세포 추적을 위한 자화강조영상)

  • Ha, Bon-Chul;Lim, Cheong-Hwan
    • The Journal of the Korea Contents Association
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    • v.10 no.8
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    • pp.249-256
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    • 2010
  • To the detect of SPIO-labelled hMSC, in vitro study on various cell concentration and in vivo molecular magnetic resonance imaging(MRI) technique using T2, $T2^*$ and SWI are compared with pathology. Cell concentration was $1.56{\times}10^4$, $3.13{\times}10^4$, $6.25{\times}10^4$, $1.25{\times}10^5$, $2.5{\times}10^5$, $5{\times}10^5\;cells/m{\ell}$ and for control $5{\times}10^5\cells/m{\ell}$. MRI technique using T2, $T^2$ and SWI. Photothrombotic infarction was located 2.5mm from bregma right, posterior. Cell injected through the tail vein of rat for 8 rats. MRI performed pre injection and post injection of 1, 3, 7 and 14days and sacrifice for pathology. MRI analysed on quantitatively. In vitro result, SWI was highest CNR as compared with $T2^*WI$, T2WI and $2.5{\times}10^5\;cells/m{\ell}$ cell concentration. In vivo result among the T2WI, $T2^WI$, SWI, T2WI is highest CNR between normal and infarction. CNR in normal-SPIO and infarction-SPIO is high score in SWI. Therefore, T2WI is good distinguish between normal and infarction, SWI are well detect SPIO-labelled hMSC from normal and infarction. Nowaday, SWI are mostly used on hemorrhage, calcification etc. in clinically, but for the future, stem cell therapy is commonly application at all disease which is good observing tool for SPIO-labelled stem cells.

Expression Analysis of Oryza sativa Ascorbate Peroxidase 1 (OsAPx1) in Response to Different Phytohormones and Pathogens (벼 ascobate peroxidase 단백질의 병원균 및 식물호르몬에 대한 발현 분석)

  • Wang, Yiming;Wu, Jingni;Choi, Young Whan;Jun, Tae Hwan;Kwon, Soon Wook;Choi, In Soo;Kim, Yong Chul;Gupta, Ravi;Kim, Sun Tae
    • Journal of Life Science
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    • v.25 no.10
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    • pp.1091-1097
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    • 2015
  • We have isolated and characterized an ascorbate peroxidase (APx) gene, OsAPx1 from rice. Northern and Western blot analyses indicated that at young seedling stage, OsAPx1 mRNA was expressed highly in root, shoot apical meristem (SAM) and leaf sheath than leaf. In mature plant, OsAPx1 gene expressed highly in root, stem and flower but weakly in leaf. OsAPx1 gene and protein expression level was induced in leaves inoculated with Magnaporthe oryzae (M. oryzae) and Xanthomonas oryzae pv. oryzae (Xoo). Phytohormones treatment showed that OsAPx1 was up-regulated by jasmonic acid (JA), but was down regulated by ABA and SA co-treatments with JA, resulting that they have antagonistic effect on pathogen responsive OsAPx1 expression. Phylogenetic analysis illustrated that Arabidopsis AtAPx1 has a close relationship with OsAPx1. In AtAPx1 knock out lines, the accumulation of O2- and H2O2 are all highly detected than wild type, revealing that the high concentration of exogenous H2O2 cause the intercellular superoxide anion and hydrogen peroxide accumulation in AtAPx1 knockout plant. These results suggested that OsAPx1 gene may be associated with the pathogen defense cascades as the mediator for balancing redox state by acting ROS scavenger and is associated with response to the pathogen defense via Jasmonic acid signaling pathway.

Studies on Molecular Plasticity of Bergmann Glia following Purkinje Cell Degeneration (조롱박신경세포의 변성에 따른 버그만아교세포의 면역조직학적 연구)

  • Yoon, Chul-Jong;Cho, Sa-Sun;Lee, Ha-Kyu;Park, Min-Chul
    • Applied Microscopy
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    • v.35 no.3
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    • pp.165-176
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    • 2005
  • Studies on molecular plasticity of Bermann glia (BG) after harmaline-induced Purkinje cell (PC) degeneration in the rat cerebellum. The intimate structural relationship between BG and PC, evidenced by the sheathing of the PC dendrites by veil-like process from the BG has been suggestive of the close functional relationship between these two cell types. However, little is known about metabolic couplings between these cells. This study designed to investigate molecular plasticity of BG in the rat cerebellum in which PCs were chemically ablated by harmaline treatment. Immunohistochemical examination reveals that harmaline induced PC degeneration causes a marked glial reaction in the cerebellum with activated BG and microglia aligned in parasagittal stripes within the vermis. In these strips, activated BG were associated with upregulaion of metallotheionein, while GLAST and was down regulated, as compared with nearby intact area where both BG are in contact with PCs. The data from this study demonstrate that BG can change their phenotypic expression when BG loose their contact with PCs. It is conceivable that activated BG may upregulate structural proteins, metallothionein expression to use for their proliferation and hypertrophy; metallothionein expression to cope with oxidative stress induced by PC degeneration and microglial activation. On the contrary, BG may down regulated expression of GLAST because sustained loss of contact with PCs would eliminate the necessity for the cellular machinery involved glutamate metabolism. In conclusion, BG might respond man to death of PCs by undergoing a change in metabolic state. It seems possible that signaling molecules released from PCs regulates the phenotype expression of BG. Also ultrastructures in the organelles of normal PC and BG are distinguished by mitochondrial appearance, and distributed vesicles at the synaptic area in the cytoplasm.

Beneficial Effect of an Agar Mask against Skin Damage Induced by UV Exposure in SKH-1 Hairless Mice (UV조사에 의해 유발된 SKH-1 hairless 마우스의 피부노화에 미치는 한천마스크의 개선효과)

  • Song, Bo Ram;Kim, Ji Eun;Yun, Woo Bin;Lee, Mi Rim;Choi, Jun Young;Park, Jin Ju;Kim, Dong Seob;Lee, Chung Yeoul;Lee, Hee Seob;Lim, Yong;Jung, Min Wook;Kim, Bae Hwan;Hwang, Dae Youn
    • Journal of Life Science
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    • v.27 no.9
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    • pp.975-985
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    • 2017
  • To investigate the beneficial effects of an agar gel mask (AGM) on UV-induced photoaging, SKH-1 hairless mice were treated with a topical application of AGM and an AGM dipped in essence (AGMdE). The mice were divided into an no radiation group, UV + AGM, UV + AGMdE, and UV + vehicle (PBS) treatment groups. Alterations in skin wrinkles, skin phenotype, histological structures, oxidative status, and toxicity were then evaluated during 4 weeks of exposure. The topical application of AGM and AGMdE inhibited wrinkle formation, suppressed the erythema index, prevented transepidermal water loss, and enhanced skin hydration. In addition, epidermal thickness recovered to a similar level as that in the no irradiation group in the UV + AGM and UV + AGMdE treatment groups compared with the UV + vehicle (distilled water) group. Furthermore, the expression levels of matrix metalloproteinase-1 (MMP-1) and tyrosinase were reduced in the UV + AGM and UV + AGMdE treatment groups, although the highest level varied. Moreover, superoxide dismutase (SOD) activity was significantly lower in the UV + AGM and UV + AGMdE treatment groups as compared with the UV + vehicle group. No significant alterations induced by most toxic compounds were measured in serum biochemical markers and liver and kidney histological features of the UV + AGM and UV + AGMdE treatment groups. These results suggest that AGM may protect against skin aging by regulating skin morphology, histopathological structures, and oxidative conditions.

A Novel Volumetric Method for Quantitation of Titanium Dioxide in Cosmetics (용량분석법을 이용한 화장품 중 티타늄옥사이드의 정량)

  • Kim, Young-So;Kim, Boo-Min;Park, Sang-Chul;Jeong, Hye-Jin;Chang, Ih-Seop
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.31 no.4 s.54
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    • pp.289-293
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    • 2005
  • Nowadays there are many sun protection cosmetics including organic or inorganic UV filter as an active ingredient. Chemically stable inorganic sunsEreen agents, usually metal oxides, we widely employed in high SPF products. Titanium dioxide is one of the most frequently used inorganic UV filters. It has been used as pigments for a long period of cosmetic history. With the development of micronization techniques, it becomes possible to incorporate titanium dioxide in sunscreen formulations without whitening effect and it becomes an important research topic. However, there are very few works related to quantitations of titanium dioxide in sunscreen products. In this research, we analyzed amounts of titanium dioxide in sunscreen cosmetics by adapting redof titration, reduction of Ti(IV) to Ti(III) and reoxidation to Ti(IV). After calcification of other organic ingredients of cosmetics, titanium dioxide is dissolved by hot sulfuric acid. The dissolved Ti(IV) is reduced to the Ti(III) by adding aluminum metals. The reduced Ti(III) is titrated against a standard oxidizing agent, Fe(III) (ammonium iron(III) sulfate), with potassium thiocyanate as an indicator In order to test accuracy and applicability of the proposed method, we analyzed the amounts of titanium dioxide in four types of sunscreen cosmetics, such as cream, make-up base, foundation and powder, after adding known amounts of titanium dioxide $(1{\sim}25w/w%)$. The percent recoveries of the titanium dioxide in four types of formulations were in the range between 96 and 105%. We also analyzed 7 commercial cosmetic products labeled titanium dioxide as an ingredient and compared the results with those of obtained from ICP-AES (Inductively Coupled Plasma-Atomic Emission Spectrometry), one of the most powerful atomic analysis techniques. The results showed that the titrated amounts were well coincided with the analyzed amounts of titanium dioxide by ICP-AES. Although instrumental analytical methods, ICP-MS (Inductively Coupled Plasma-Mass Spectrometry) and ICP-AES, are the best for the analysis of titanium, it is hard to adopt because of their high prices for small cosmetic companies. It was found that the volumetric method presented here gat e quantitative and reliable results with routine lab-wares and chemicals.

Analysis of the Stage and Performance Elements for Bongsudang-jinchan Banquet in Joseon Dynasty (봉수당진찬(奉壽堂進饌)의 무대와 공연 요소 분석)

  • Song, Hye-jin
    • (The) Research of the performance art and culture
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    • no.18
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    • pp.413-444
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    • 2009
  • This paper is an analysis of stage and performance elements for the ceremonial procedures and dance featured in bongsudang-jinchan, a feast celebrating the 60th birthday of Hyegyeong-gung Hongssi (Crown Princess Hong of Hyegyeonggung), the mother of King Jeongjo, which took place in Hwaseong haegung palace in 1795. The primary sources used are data on bongsudangjinchan recorded in Wonhaeng-eulmyojeongriuigwe, Jeongjo-sillok, Hongjae-jeonseo, pictorial sources such as Folding Screens of Hwaseong-neunghaeng and Hwaseong Ilgi, which is a journal in Korean by Yi Hui-pyeong. A court ceremony to offer music, dance, flowers, and food, as well as wine and poetry which express the sentiments of chung (fidelity) and hyo (filial piety) was considered a national ceremony and has constituted a unique musical culture during the 500 years of Joseon dynasty. However, after the fall of Joseon dynasty, ceremonial music and dance, which have been organically linked within the overall symbolic system of ye (courtesy), became scattered to become independent 'pieces.' As a result, all of their philosophy, principles, and the time-space interpretation of court music and dance became greatly reduced, leaving only the artistic expression and formal structure of the music and dance to become emphasized. Since the 1990s, there has been many research and events aiming to re-create the court ceremonial tradition, resulting in the increase of the related performance activities. This is especially true with bongsudang-jinchan, which is now being performed on modern stage in various forms. However there are still many problems to be solved, such as the issue of re-creating and restoring the original, and the question of artistic value found in the traditional pieces. Until now, much focus has been paid to the outer re-construction of uiju document as recorded in Wonhaeng-eulmyo-jeongriuigwe. On the other hand, there lacked an in-depth study which analyzes the stage situation and performance elements. Therefore in this paper, after focusing on the stage structure and performance elements, it is concluded that bongsudang-jinchan, the only court feast to be held in Haeng gung, not only consists of the fundamental aspects of court performance principle as 'governing through ye and ak (music),' but also served as an important occasion to bring together the sovereign and the subject. Bongsudang-jinchan had features of both naeyeon (feast for ladies) and oeyeon (feast for gentlemen). It minimized the use of screens and allowed every guest to enjoy food, music, and dance together, but provided a separate tent for foreign guests, maintaining the ideal balance between equality and distinction among different gender and social status. A screen symbolizing the venue for the feast is placed for all of the government officials. The king then pronounces the beginning of the banquet in which the ideal of gunsin-dongyeon (king and officials dining together) is realized. This indicates that bongsudang-jinchan, compared to other court ceremonies that emphasize the principle of yeak (courtesy and music), focuses more on the spirit of harmony and rapprochement. The king played a more active role in bongsudang-jinchan than in any other royal feasts. Examples as recorded in uiju documents are; Jeongjo's conversation with his retainers after the 7th wine, king's bestowing of food and flowers to the officials, writing his own majesty's poems with regard to the festival, and asking the retainers to write replying poems. All these played an important part in making the occasion more rich, extensive, and meaningful. Moreover, as analysis of the structure of orchestral music and court dance featured in bongsudang-jinchan shows, it was like any other court banquet in that it employed minimal use of extravagance in movements and conversation. However, the colors and tonal texture used in the music and dance were more brilliant in this case. Compared to other banquets that took place before king Jeongjo, the dance style was more diverse, which included some of the latest additions. There were past performances arranged anew. Noteworthy are; the incorporation of "Seonyurak (Boat Dance)" and "Geommu (Sword Dance)," traditionally used for local officials and civilians feast, to suit the court taste; and the use of saenghwang (mouth organ), which was a rising instrument in pungnyubang (literati's private salon), for "Hakmu (Cranes Dance)." This especially indicates the nature of the 'open structure' pursued by the court banquets at the time, which strove to break away from the traditional rules and customs and accept something new.