• 제목/요약/키워드: 5'-Modification

검색결과 2,294건 처리시간 0.023초

$IO_4$-산화전분 변형에 의한 밀 $\beta$-Amylase의 안정성 증가 (Stabilization of Wheat $\beta$-Amylase by Modification with $IO_4$-Oxidized Starch)

  • 안용근
    • 한국식품영양학회지
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    • 제13권4호
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    • pp.348-352
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    • 2000
  • 과요오드산-산화전분으로 밀 $\beta$-amylase(Himaltosin GL. 일본한큐바이오사)를 변형시켜서 인공당단백질을 만들었다. pH 8.0에서 변형한 효소는 비변형효소의 96%. pH 9.7에서 변형한 효소는 17%의 활성이 남았다. 6$0^{\circ}C$에서의 열 안정성은 $\alpha$-cyclodextrin ( $\alpha$-CD) 존재 시에 변형하여 $\alpha$-CD 존재시에 분석한 효소는 10분 뒤에 비활성의 8%가 남은 반면 변형하지 않은 효소는 5% 밖에 남지 않았다. pH안정성은 변형시켜서 $\alpha$-CD존재 하에 분석한 효소가 가장 높아서 pH 2~5와 6~12에서 안정성이 매우 증가하였다. HPLC분석 결과 효소는 하나의 피크를 나타냈으며 변형시킨 것은 당결합으로 분자량이 커져서 유출시간이 약간 빨라졌다.

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Response modification factor of suspended zipper braced frames

  • Abdollahzadeh, Gholamreza;Abbasi, Mehdi
    • Steel and Composite Structures
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    • 제18권1호
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    • pp.165-185
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    • 2015
  • The suspended zipper bracing system is suggested to reduce the flaws of ordinary zipper braced and concentric inverted V braced frames. In the design procedure of suspended zipper bracing systems, columns and top story truss elements are strengthened. This bracing system show different performances and characteristics compared with inverted V braced and ordinary zipper frames. As a result, a different response modification factor for suspend zipper frames is needed. In this research paper, the response modification factor of suspended zipper frames was obtained using the incremental dynamic analysis. Suspended zipper braced frames with different stories and bay lengths were selected to be representations of the design space. To analyze the frames, a number of models were constructed and calibrated using experimental data. These archetype models were subjected to 44 earthquake records of the FEMA-P695 project data set. The incremental dynamic analysis and elastic dynamic analysis were carried out to determine the yield base shear value and elastic base shear value of archetype models using the OpenSEES software. The seismic response modification factor for each frame was calculated separately and the values of 9.5 and 13.6 were recommended for ultimate limit state and allowable stress design methods, respectively.

행동수정 프로그램과 에어로빅 운동의 시점별 체중조절 효과 비교 (Effects of Weight Control by Behavior Modification and Aerobic Exercise)

  • 박종성;정승교
    • 보건교육건강증진학회지
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    • 제12권2호
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    • pp.62-72
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    • 1995
  • We studied the effects of behavior modification and aerobic exercise on body weight, degree of obesity, % body fat, triceps skinfold thickness, blood pressure and eating behavior among overweight middle school girls. 15 girls participated in the behavior modification program by joining 60-90 minute group session weekly. The aerobic exercise program was given to 13 girls 3 times per week with 60 minutes each time. The data were obtained before treatment, after 4 and 8 weeks after treatment. In analyzing the data, repeated measures ANOVA were adopted. The results were as follows ; 1. For the changes of body weight between 2 groups, body weight of behavior modification groups decreased significantly than these of aerobic exercise group at 4 and 8 weeks after treatment, 2. For the changes of degree of obesity between 2 groups, there were no significant differences over time, 3. The analysis of change of % body fat did not reveal significant differences between 2 groups over time, 4. The changes of triceps skinfold thickness were significant differences between 2 groups over time, 5. For the changes of systolic blood pressure between 2 groups, there were significant differences over time. At 4 weeks after treatment, systolic blood pressure of behavior modification group decreased significantly than these of aerobic exercise group. 6. The changes of diastolic blood pressure were significant differences between 2 groups over time.

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Salsolinol, a tetrahydroisoquinoline-derived neurotoxin, induces oxidative modification of neurofilament-L: protection by histidyl dipeptides

  • Kang, Jung-Hoon
    • BMB Reports
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    • 제45권2호
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    • pp.114-119
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    • 2012
  • Salsolinol (1-methyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline) is a compound derived from dopamine metabolism and is capable of causing dopaminergic neurodegeneration. Oxidative modification of neurofilament proteins has been implicated in the pathogenesis of neurodegenerative disorders. In this study, oxidative modification of neurofilament-L (NF-L) by salsolinol and the inhibitory effects of histidyl dipeptides on NF-L modification were investigated. When NF-L was incubated with 0.5 mM salsolinol, the aggregation of protein was increased in a time-dependent manner. We also found that the generation of hydroxyl radicals (${\bullet}OH$) was linear with respect to the concentrations of salsolinol as a function of incubation time. NF-L exposure to salsolinol produced losses of glutamate, lysine and proline residues. These results suggest that the aggregation of NF-L by salsolinol may be due to oxidative damage resulting from free radicals. Carnosine, histidyl dipeptide, is involved in many cellular defense processes, including free radical detoxification. Carnosine, and anserine were shown to significantly prevent salsolinol-mediated NF-L aggregation. Both compounds also inhibited the generation of ${\bullet}OH$ induced by salsolinol. The results indicated that carnosine and related compounds may prevent salsolinol-mediated NF-L modification via free radical scavenging.

대관령 산악지역 안개조절을 위한 구름특성 조사 (Investigation on Cloud Properties for Fog Modification at Daegwallyeong Mountains)

  • 양하영;오성남
    • 한국방재학회 논문집
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    • 제5권2호
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    • pp.45-56
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    • 2005
  • 구름씨뿌리기 방법에 의한 안개조절의 가능성을 파악하기 위해 대관령 산악지역의 구름특성을 분석하였다. 구름씨뿌리기에 의한 안개조절은 흡습성 물질을 이용한 온안개 소산에 집중되고 있다. 이 연구에서는 관측된 안개의 특성을 통계적으로 분석하고 이에 대해 논의하였다. 안개의 대부분은 여름철에 발생한 온안개이고 6시전 이른 아침에 발생하여 7시${\sim}$9시 소산되는 특성을 보인다. 봄철과 겨울철에는 AgI시딩에 적합한 동풍계열의 냉안개가 발생한다. 이 결과로부터 안개소산에 적합한 구름씨뿌리기방법과 물질을 추론할 수 있으며 이는 실제 냉안개와 온안개 실험에 적용할 수 있다.

알칼리와 CTAB 처리에 의한 양모섬유의 개질(I) -화학적 성질의 변화- (Modification of Wool Treated with Alkali and Alkali/CTAB (I) -Changes of chemical properties-)

  • 김영리;유효선
    • 한국의류학회지
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    • 제20권5호
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    • pp.728-737
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    • 1996
  • The purpose of this study is to investigate the change of the chemical properties of wool treated with six kinds of alkali (NaOH, Naac03, NH40H, NH2CH3CH30H, TMAH and BTMAH) with or without CTAB. Content of bound fatty acid liberated from wool surface, elemental composition and allw6rden time were measured to compare the surface modification of untreated and alkali treated wool. Also, the chemical degradation of the fiber was investigated by measuring cystine contents and urea-hydrogensulfite solubility. The result were as follows: 1. By the alkali treatment of wool, the covalently bound fatty acid of the epicuticle was removed and the allworden time was shortened, and in the case of wool treated with TMAH, BTMAH, the allw6rden sacs were formed unevenly and rarely. Also, cystine contents and urea-hydrogensulfite solubility were decreased by alkali treatment on wool. 2. The modification of epicuticle and the chemical degradation of wool were occurred due to alkaline hydrolysis in the order of TMAH, BTMAH > NaOH, Na3c03> NH2CH3CHaOH, NH40H. 3. As a treating time increased, the modification of epicuticle and chemical degradation of wool were accelerated. By the addition of CTAB to the alkali solution, the modification of epicuticle was increase, and the cystine contents and urea-hydrogensulfite solubility were reduced than that of wool teated with alkli without CTAB due to reduction of negative charge on the wool surface by the adhesion of CTAB.

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Response modification factor of mixed structures

  • Fanaie, Nader;Shamlou, Shahab O.
    • Steel and Composite Structures
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    • 제19권6호
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    • pp.1449-1466
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    • 2015
  • Mixed structures consist of two parts: a lower part and an upper part. The lower part is usually made of concrete while the upper part is made of steel. Analyzing these structures is complicated and code-based design of them has many associated problems. In this research, the seismic behavior of mixed structures which have reinforced concrete frames and shear walls in their lower storeys and steel frames with bracing in their upper storeys were studied. For this purpose, seventeen structures in three groups of 5, 9 and 15 storey structures with different numbers of concrete and steel storeys were designed. Static pushover analysis, linear dynamic analysis and incremental dynamic analysis (IDA) using 15 earthquake records were performed by OpenSees software. Seismic parameters such as period, response modification factor and ductility factor were then obtained for the mixed (hybrid) structures using more than 4600 nonlinear dynamic analysis and used in the regression analysis for achieving proper formula. Finally, some formulas, effective in designing such structures, are presented for the mentioned parameters. According to the results obtained from this research, the response modification factor values of mixed structures are lower compared to those of steel or concrete ones with the same heights. This fact might be due to the irregularities of stiffness, mass, etc., at different heights of the structure. It should be mentioned that for the first time, the performance and seismic response of such structures were studied against real earthquake accelerations using nonlinear dynamic analysis, andresponse modification factor was obtained by IDA.

천연광물의 양극성 표면개질을 이용한 상수원수 중 중금속제거 특성 (Heavy Metal Removal from Drinking Water using Bipolar Surface Modified Natural Mineral Adsorbents)

  • 김남열;김영희
    • 한국환경보건학회지
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    • 제45권6호
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    • pp.561-568
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    • 2019
  • Objectives: The most commonly detected heavy metals in rocks and soils, including Pb, Cd, Cu, Fe, Mn and As, are representative pollutants discharged from abandoned mines and have been listed as potential sources of contamination in drinking water. This study focused on increasing the removal efficiency of heavy metals from drinking water resources by surface modification of natural adsorbents to reduce potential health risks. Methods: Iron oxide coating and graft polymerization with zeolites and talc was conducted for bipolar surface modification to increase the combining capacity of heavy metals for their removal from water. The removal efficiency of heavy metals was measured before and after the surface modification. Results: The removal efficiency of Pb, Cu, and Cd by surface modified zeolite showed 100, 92, and 61.5%, respectively, increases compared to 64, 64, and 38% for non-modified zeolite. This implies that bipolar surface modified natural adsorbents have a good potential use in heavy metal removal. The more interesting finding is the removal increase for As, which has both cation and anion characteristics showing 27% removal efficiency where as non-modified zeolite showed only 2% removal. Conclusions: Zeolite is one of the most widely used adsorptive materials in water treatment processes and bipolar surface modification of zeolite increases its applicability in the removal of heavy metals, especially As.

Chemical Modification of Intracellular Cytosine Deaminase from Chromobacterium violaceum YK 391

  • Kim, Jung;Kim, Tae-Hyun;Yu, Tae-Shick
    • Biotechnology and Bioprocess Engineering:BBE
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    • 제10권3호
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    • pp.180-185
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    • 2005
  • Cytosine deaminase (cytosine aminohydrolase, EC 3.5.4.1) stoichiometrically catalyzes the hydrolytic deamination of cytosine and 5-fluorocytosine to uracil and 5-fluorouracil, respectively. Amino acid residues located in or near the active sites of the intracellular cytosine deaminase from chromobacterium violaceum YK 391 were identified by chemical modification studies. The enzymic activity was completely inhibited by chemical modifiers, such as 1mM NBS, chloramine-T, $\rho-CMB,\;\rho-HMB$ and iodine, and was strongly inhibited by 1mM PMSF and pyridoxal 5'-phosphate. This chemical deactivation of the enzymic activity was reversed by a high concentration of cytosine. Furthermore, the deactivation of the enzymic activity by $\rho-CMB$ was also reversed by 1mM cysteine-HCI, DTT and 2-mercaptoethanol. These results suggested that cysteine, tryptophan and methionine residues might be located in or near the active sites of the enzyme, while serine and lysine were indirectly involved in the enzymic activity. The intracellular cytosine deaminase from C violaceum YK 391 was assumed to be a thiol enzyme.

과요오드산 산화전분 변형에 의한 아밀라아제의 안정화 (Stabilization of Amylolytic Enzymes by Modification with Periodate-Oxidized Soluble Starch)

  • 안용근
    • 한국식품영양학회지
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    • 제11권5호
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    • pp.561-564
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    • 1998
  • The stabilizatio of amaylolytic enzyme such as $\beta$-amylase of barley, $\beta$-amylase of wheat, $\beta$-amylase of sweet potato, $\alpha$-amylase of Bacillus licheniformis, $\alpha$-amylase of Aspergillus sp. and $\alpha$-glucosidase of Aspergillus awamori was attained by modification with periodate-oxidized soluble starch. The pH stability of modified enzyme was increased at pH 9 for $\beta$-amylase of sweet potato, pH 3~5 and 8~11 for $\beta$-amylase of barley, pH 2~3 and 7~12 for $\beta$-amylase of wheat and pH 6 for $\alpha$-glucosidase of Aspergillus awamori. Thermal stability increased 17.6% for $\alpha$-amylase of Aspergillus sp. at 6$0^{\circ}C$ for 10min, 30% for $\alpha$-amylase of Bacillus licheniformis at 10$0^{\circ}C$ for 5min and 4.5% for $\alpha$-amylase of sweet potato at 6$0^{\circ}C$ for 10min compared with those of native enzymes.

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