• 제목/요약/키워드: surface characteristic

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Prevalence of Aflatoxin Induced p53 Mutation at Codon 249 (R249s) in Hepatocellular Carcinoma Patients with and without Hepatitis B Surface Antigen (HBsAg)

  • Chittmittrapap, Salyavit;Chieochansin, Thaweesak;Chaiteerakij, Roongruedee;Treeprasertsuk, Sombat;Klaikaew, Naruemon;Tangkijvanich, Pisit;Komolmit, Piyawat;Poovorawan, Yong
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.12
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    • pp.7675-7679
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    • 2013
  • Background: A missense mutation in exon 7 (R249S) of the p53 tumor suppressor gene is characteristic of aflatoxin B1 (AFB1) exposure. AFB1 is believed to have a synergistic effect on hepatitis virus B (HBV) carcinogenesis. However, results of studies comparing R249S prevalence among patients are conflicting. The aim of this study was to determine the prevalence of the R249S mutation in hepatocellular carcinoma (HCC) patients with or without positive HBsAg. Materials and Methods: Paraffin embedded liver tissues were obtained from 124 HCC patients who underwent liver resection and liver biopsy in King Chulalongkorn Memorial Hospital. Restriction fragment length polymorphism (RFLP) was utilized to detect the R249S mutation. Positive results were confirmed by direct sequencing. Results: Sixty four (52%) patients were positive for HBsAg and 18 (15%) were anti-HCV positive. 12 specimens tested positive by RFLP. Ten HCC patients (8.1%) were confirmed to be R249S positive by Sanger sequencing (AGG to AGT). Out of these 10, six were HBsAg positive, and out of the remaining 4, two were anti-HCV positive. The R249S prevalence among HCC patients with positive HBsAg was 9.4% compared to 6.7% for HBsAg negative samples. Patients with the R249S mutation were younger ($55{\pm}10$ vs $60{\pm}13$ year-old) and tended to have a more advanced Edmonson-Steiner grade of HCC, although differences did not reach statistical significance. Conclusions: Our study shows moderate prevalence of aflatoxin B1-related p53 mutation (R249S) in HCC with or without HBsAg. HBsAg positive status was not associated with R249S prevalence.

Feasibility Study on a Defrost Control Method by Using a Photoelectric Sensors (광센서를 이용한 제상제어 방법에 대한 타당성 검토)

  • Jeon, Chang-Duk;Kim, Dong-Seon;Lee, Seung-Jun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.6
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    • pp.3389-3395
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    • 2014
  • Conventional methods, such as the clock time control method and temperature difference control method, for defrost control often encounter mal-defrost and a waste of energy. Therefore, a more efficient method is needed to control defrosting precisely. A photoelectric sensor unit consisting of an emitter and a collector was installed in the front of outdoor heat exchanger. Accurate defrost control was performed by monitoring and using the change in output voltage according to the presence of frost. In this study, experiments were performed to determine if the performance and characteristic curves obtained using the clock time control method can be reproduced using a photoelectric sensor under the heating and defrosting capacity test condition described at KS C 9306. The output voltage of the phototransistor (receiver) and heating capacity, power consumption, and surface temperature of the outdoor heat exchanger, were compared. The results showed that photoelectric sensors can be used as a defrost control method. On-off control timing of the clock time defrosting method was in good agreement with those predicted by the output voltage of the photoelectric sensor.

Planning Indicators for Spatial Characteristics Evaluation of Urban Public Space - the Weight Analysis for Activation of Public Space (도시 공공공간의 공간적 특성 평가를 위한 계획 지표 연구 - 공공공간 활성화를 위한 중요도 분석)

  • Lee, Hoon-Gill;Lee, Joo-Hyung
    • The Journal of the Korea Contents Association
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    • v.15 no.9
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    • pp.588-598
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    • 2015
  • This study derives planning items and indicators that should be considered in order to activate public space in terms of the spatial characteristics of the public space was to analysis the importance in the public officials/academics and practitioners side. Derived in accordance with spatial planning topics characteristic of public space through previous research to them and after a detailed selection indicators in Christopher Alexander's Pattern Language was so lead through the FGI. Derived surface was subjected to the significance analysis AHP through the survey expert. For this study, the importance of the spatial characteristics of the public space are working professionals accessibility, publicity, connectivity, spatiality, amenity, placeness the order, public officials/academics accessibility, amenity, placeness, connectivity, spatiality, publicity the order. In addition, professionals working in the comprehensive analysis of the most important priority was to recognize the hierarchy of open space, public officials/academics appeared to have an open space on the street the most important. The results obtained in this study will be used as an index that can be used in planning and evaluation for consideration of the next active public space.

Study on Calcination Characteristics of Limestones for In-Furnace Desulfurization in Oxy-Fuel Combustion (순산소연소 조건에서 석회석의 소성특성 및 로내탈황에 관한 연구)

  • An, Young-Mo;Jo, Hang-Dae;Choi, Won-kil;Park, Yeong-Sung;Keel, Sang-In;Lee, Hyung-Keun
    • Journal of Korean Society of Environmental Engineers
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    • v.31 no.5
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    • pp.371-377
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    • 2009
  • In oxy-fuel combustion, $CO_2$ concentration in the flue gas may be enriched up to 95% owing to the gas recirculation. Under the high $CO_2$ concentration, the calcination characteristic of limestone is different from that of the conventional air combustion system. In this study, three types of limestone taken from different regions in Korea were used as $SO_2$ absorbent and their calcination characteristics depending on calcination temperature were investigated. The experiments were performed to examine the effects of operating variables such as absorbent species, reaction temperatures on the $SO_2$ removal efficiency and reacted limestone particles were captured to examine the sulfur contents. The degree of calcination and the specific surface area increased with calcination temperature and $SO_2$ removal efficiency increased with reaction temperature. The results showed remarkable difference in $SO_2$ removal efficiencies between the limestone types. The sulfur content of the reacted limestone with the highest $SO_2$ removal efficiency was about 10%.

Disinfection Effects of Electrolyzed Water on Strawberry and Quality Changes during Storage (전기분해수 처리에 의한 딸기의 살균 효과 및 저장 중 품질변화)

  • Jeong Jin-Woong;Kim Jong-Hoon;Kwon Ki-Hyun;Park Kee-Jai
    • Food Science and Preservation
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    • v.13 no.3
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    • pp.316-321
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    • 2006
  • Disinfection of electrolyzed water (EW) on strawberry by immersion washing and quality changes during storage at $5^{\circ}\C$ was compared with one immersed in chlorine water and not treated. Total count of strawberry washed with EW by immersion in 10 volumes of EW for 20 min was decreased to about 2 log cycle compared to the untreated And rate of microbial growth during storage was lower than ethers. Decaying ratio in strawberry treated with electrolyzed low-alkalinewater (EW-2) showed lower as of 10% level after 5 days of storage compared) to the untreated and the treated with chlorine water (CW). Hardness in the treatment of EW was not changed significantly until 3 days of storage, after then rather increased. Change in surface color of strawberries was observed; L value in the CW treated and the untreated increased whereas it decreased in the treatment of EW. And color difference(${\Delta}E$) during storage was observed the lowest in the untreated until 3 days of storage. The initial value of residual chlorine in the treatment of EW was at the level of $0.04{\sim}0.06ppm$, and $1{\sim}3$ days later showed almost the equal value to level of $0.02{\sim}0.03ppm$ in all treatments. Sensory characteristic during storage was preferable on strawberry washed with EW (EW-1 and EW-2) to the other treatments.

The Dissolution Characteristics of Metal Compounds in Soil Application Experiment using Sewage Treatment Sludge mixed with Oyster shells (하수슬러지 및 굴껍질의 토지주입시 금속성분의 용출특성에 관한 연구)

  • Kim, Chul;Moon, Jong-Ik;Shin, Nam-Cheol;Ha, Sang-An;Sung, Nak-Chang;Huh, Mock
    • Journal of the Korea Organic Resources Recycling Association
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    • v.9 no.2
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    • pp.71-76
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    • 2001
  • Recently, sludge disposal becomes one of the most serious environmental problems. Because the landfilling and ocean dumping of sludge materials will be prohibited in the near future, the proper treatment?disposal methods should be investigated. Also, oyster shells, piled at the coast, cause adverse effects in coastal fishery, public water surface, natural landscape, public health and so on. Thus, the purpose of this study is to evaluate the dissolution characteristic of metal compounds during soil application experiment using sewage treatment sludge mixed with oyster shells. The dissolution experiment conducted 100days under artificial rainfall and farming soil, mixed with sewage treatment sludge and oyster shells, was put into the pots(approx. 0.5L). The results from dissolution experiment as follows. 1. K, Na was $5{\sim}20mg/{\ell}$, and Ca was less than $90mg/{\ell}$. 2. Heavy metals such as Cd, Cu, As, Pb, Cr, Hg are dissoluted far less than the soil pollution guideline. The application of sewage sludge mixed with oyster shells increases pH(soil acidity)and buffer capacity(CEC) of farming soil, and heavy metals are thought to be attached to soil as insoluble forms.

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Formation of Alunite and Schwertmannite under Oxidized Condition and Its Implication for Environmental Geochemistry at Dalseong mine (산화환경하에서 명반석, 슈베르트마나이트의 형성특징과 환경지구화학적 의미: 달성광산)

  • 추창오;이진국;조현구
    • Journal of the Mineralogical Society of Korea
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    • v.17 no.1
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    • pp.37-47
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    • 2004
  • Sulfates such as alunite and schwertmannite formed under oxidation condition play a important role in geochemical processes taken place at waste dumps and a creek from Dalseong mine, Daegu. Water chemistry shows pH decreases from upstream toward downstream creek, mainly due to formation of schwertmannite that is the most abundant phase along the creek. The removal of Al from the creek is preferentially attributed to formation of Al-bearing minerals and Al-sulphates. Among them, alunite is the most important Al-sink phase that occurs at higher pH than $pK_1$, Al hydrolysis constant. With high saturation index, alunite formed at the creek has a spherical form, commonly associated with schwertmannite. Secondary minerals formed on the surface of altered or weathered surfaces of heavy metals from the wasted dump that underwent severe oxidation, where alunite has characteristic habits which are spheric, radiating, and botrytis-like aggregates. Natroalunite occurs in association with alunite, or as mixtures of both of them. Because the pH decreases with distance due to formation of schwertmannite, although total contents of dissolved ions slowly lessen at least in the AMD, it is expected that the minerals precipitated at the creek can be exposed to subsequent dissolution, which may induce possible environmental problems.

The Photovoltaic Effect of Iodine-Doped Metal Free Phthalocyanine/ZnO System (Ⅱ). The Photovoltaic Effect of $ZnO/H_2Pc(I)_x$ Dispersed in Poly(9-vinylcarbazole) (요오드가 도핑된 무금속 프탈로시아닌/산화아연계의 광기전력 효과 (Ⅱ). Poly(9-vinylcarbazole)에 분산된 $ZnO/H_2Pc(I)_x$계의 광기전력 효과)

  • Heur, Soun-Ok;Kim, Young-Soon
    • Journal of the Korean Chemical Society
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    • v.39 no.3
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    • pp.176-185
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    • 1995
  • To improve photosensisitizing efficiency of ZnO/$H_2Pc(I)_x$ system, ZnO/$H_2Pc(I)_x$ system was dispersed in a typical photoconductive polymer of poly(9-vinylcarbazole)(PVCZ). The iodine dopant level(x) of ZnO/${\chi}-H_2Pc(I)_x$ is proportional to concentration of iodine, whereas x of ZnO/${\beta}-H_2Pc(I)_x$ decreased from the highest x=0.97 at more than $6.3{\times}10^{-3}$ M iodine solution. The Raman spectra of ZnO/${\chi}-H_2Pc(I)_x$ at 514 nm exhibited characteristic $I_3^-$ patterns in the range of 50∼550 $cm^{-1}$ at $x{\geq}0.57.$ The surface photovoltage of ZnO/${\chi}-H_2Pc(I)_{0.48}$/PVCZ was approximately 1.6 times greater than ZnO/${\chi}-H_2 Pc(I)_{0.48}$ and was 1.8 times of ZnO/${\chi}-H_2Pc(I)_{0.57}$/PVCZ at 670 nm. With ZnO/$H_2Pc(I)_x$/PVCZ, the highest iodine dopant levels showed a higher photovoltage. Therefore the injection of holes from H2Pc into PVCZ resulted in that photosensisitizing effect of ZnO/$H_2Pc(I)_x$/PVCZ system was improved compared to ZnO/$H_2Pc(I)_x$ case.

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The Ecological Characteristics of the Winter Cherry Bug Acanthocoris sordidus (Hemiptera) and the Effects of Colony Formation on its Potential as an Insect Pest (잠재해충 꽈리허리노린재(Acanthocoris sordidus, Coreidae, Hemiptera)의 무리군 형성에 따른 생태적 특성)

  • Kang, Chan Yeong;Ryu, Tae Hee;Kwon, Hye Ri;Yu, Yong Man;Youn, Young Nam
    • Korean journal of applied entomology
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    • v.55 no.3
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    • pp.235-243
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    • 2016
  • The winter cherry bug, Acanthocoris sordidus (Thunberg), is an insect pest hat damages plants from Solanaceae and Convolvulaceae. The developmental period from egg to adult averages 76 days at $25^{\circ}C$. Adult egg-laying occurred irregularly via spawning, averaging 195 (up to 468) eggs per individual on the abaxial leaf surface of the host plant. Results of linear regression indicated that the lower developmental threshold temperature was $13.9^{\circ}C$ and the effective accumulated temperature was 526.3 DD. Data from a pepper field in 2015 indicated that overwintering adults first appeared during late June (daily average temperature = $25.7^{\circ}C$), reaching maximum density by early September. A choice test examining colonization preferences using a net cage and a Y-tube olfactometer revealed that females gravitated toward conspecifics (other females, males, or both), whereas males moved toward empty areas. Finally, we found that communal breeding results in a longer developmental period and higher eclosion rates than solitary breeding. Developmental periods and eclosion rates were also for colonies in a large space than for those in a small space. This outcome suggests that colonization effects on insect development are stronger in a smaller area.

Synthesis of Ti-SBA-15 Doped with Lanthanide Ions and Their Photocatalytic Activity (란탄족 이온이 도핑된 Ti-SBA-15의 합성 및 그들의 광촉매 활성)

  • Hong, Seong-Soo
    • Clean Technology
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    • v.26 no.1
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    • pp.7-12
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    • 2020
  • Ti-SBA-15 catalysts doped with lanthanide ions (Ln/Ti-SBA-15) were successfully synthesized using conventional hydrothermal method. In addition, they were characterized by XRD, FT-IR, DRS, BET, and PL. The activity of these materials on the photocatalytic decomposition of methylene blue under ultraviolet light irradiation was also examined. Ti-SBA-15 catalysts doped with various lanthanide ions maintained their mesoporous structure. The pore size and pore volume of Ln/Ti-SBA-15 materials decreased but their surface area increased upon the doping of lanthanide ion. Ln/Ti-SBA-15 materials exhibited the type IV nitrogen isotherm with desorption hysteresis loop type H2, which was characteristic of mesoporous materials. The size of hysteresis increased in the doping of lanthanide ions on Ti-SBA-15 material. There was no absorption in the visible region (> 400 nm) regardless of the doping of lanthanide ions to TiO2 particles, while the broad bands at 220 nm appeared at the Ln/Ti-SBA-15 samples, indicating the framework incorporation of titanium into SBA-15. 1 mol% Pr/ Ti-SBA-15 catalysts showed the highest photocatalytic activity on the decomposition of methylene blue but the Ti-SBA-15 catalysts doped with Eu, Er, and Nd ions showed lower activity compared to pure Ti-SBA-15 catalyst. The PL peaks appeared at about 410 nm at all catalysts while the excitonic PL signal was proportional to the photocatalytic activity for the decomposition of methylene blue.