• 제목/요약/키워드: $\beta$-type

검색결과 2,066건 처리시간 0.032초

A simplified normalized cumulative hysteretic energy spectrum

  • Sun, Guohua;Gu, Qiang;Fang, Youzhen
    • Earthquakes and Structures
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    • 제12권2호
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    • pp.177-189
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    • 2017
  • For energy-based seismic design, a simplified normalized cumulative hysteretic energy spectrum proposed for obtaining hysteretic energy as energy demand is the main objective in this paper. The dimensionless parameter, ${\beta}_{Eh}$, is presented to express hysteretic energy indirectly. The ${\beta}_{Eh}$ spectrum is constructed directly through subtracting the hysteretic energy of single degree-of-freedom (SDOF) system energy equation. The simplified ${\beta}_{Eh}$ spectral formulation as well as pseudo-acceleration spectrum of modern seismic provisions is developed based on the regression analysis of the large number of seismic responses of SDOF system subjected to earthquake excitations, which considers the influence of earthquake event, soil type, damping ratio, and ductility factor. The relationship between PGV and PGA is established according to the statistical analysis relied on a total of 422 ground motion records. The combination of ${\beta}_{Eh}$ spectrum and PGV/PGA equation allows determining the cumulative hysteretic energy as a main aseismic design indicator.

Regulation of Pathological Markers during Hepatic Fibrogenesis in Rats

  • Jeong, Won-il;Jeong, Kyu-shik
    • 한국수의병리학회:학술대회논문집
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    • 한국수의병리학회 2003년도 추계학술대회초록집
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    • pp.16-16
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    • 2003
  • Hepatic fibrosis is a common response to various chronic hepatic injuries and occurs as a consequence of the transformation of hepatic stellate cells into myofibroblasts (MFBs) producing abnormal extracellular matrix which is mainly induced by transforming growth factor-beta (TGF-${\beta}$), especially TGF-${\beta}$1 [1,2]. As the liver becomes fibrotic, there are both quantitative and qualitative changes in several pathological markers related to the hepatic fibrosis. These fibrotic markers in liver are mainly consisted of several proteins and cytokines, but sometimes included specific type cells. The aim of this study was to detect expression and change of markers (TGF-${\beta}$, mallory body, cytokeratin, ${\alpha}$-SMA, hypoxia, collagen) during hepatic fibrogenesis. (omitted)

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Immobilization of MTBE using cyclodextrins

  • Baek, Ki-Tae;Yang, Ji-Won
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2003년도 총회 및 춘계학술발표회
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    • pp.120-123
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    • 2003
  • Immobilization behavior of methyl tert-butyl ether (MTBE) by various cyclodextrins(CDs) was studied to investigate the feasibility of MTBE removal using cyclodexrins. Even though MTBE has relatively low hydrophobicity and higher polarity compared to other organics, it was effectively immobilized by CDs. The immobilization isotherms was shown as a type of Freundlich isotherms, and the immobilization capacity of -CDs was the largest among natural COs. The initial apparent association constant for MTBE-CD complex follows the order : gamma = beta > methyl-beta > hydroxypropyl beta > alpha. These differences of the constants are related to the size of MTBE and CDs. The size of beta-CD and gamma-CD is large to encapsulate MTBE molecule into the cavity, which that of alpha-CB is too small to encapsulate MTBE.

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Streptococcus faecalis의 pAM $\beta$$_1$을 lactobacillus casei로의 전이에 영향을 미치는 요인 (Factors affecting transfer frequency of pAM$\beta$$_1$from streptococcus faecalis to lactobacillus casei)

  • 허정원;강성훈
    • 미생물학회지
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    • 제28권3호
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    • pp.188-191
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    • 1990
  • The streptococcal plasmid pAM$\beta_{1}$ (erythromycin resistance)was transferred via conjugation from Streptococcus faecalis DS 5 to Lactobacillus casei YIT 9018 by a filter mating method. The transfer frequency depended greatly on the type, pore size and side(front or back) of membrane filter. Water passing through a membrane under reduced pressure induced very tight contact between the cells, increased the transconjugation frequency about 1.3 to 37-fold when Millipore membrane filter (0.45.$\mu$m, front side up) was used.

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Sensory Difference Testing: The Problem of Overdispersion and the Use of Beta Binomial Statistical Analysis

  • Lee, Hye-Seong;O'Mahony, Michael
    • Food Science and Biotechnology
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    • 제15권4호
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    • pp.494-498
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    • 2006
  • An increase in variance (overdispersion) can occur when a binomial statistical analysis is applied to sensory difference test data in which replicate sensory evaluations (tastings) and multiple evaluators (judges) are combined to increase the sample size. Such a practice can cause extensive Type I errors, leading to serious misinterpretations of the data, especially when traditional simple binomial analysis is applied. Alternatively, the use of beta binomial analysis will circumvent the problem of overdispersion. This brief review discusses the uses and computation methodology of beta binomial analysis and in practice evidence for the occurrence of overdispersion.

Study of Retention of Mono-Substituted Phenols in Reversed-Phase Liquid Chromatography Based on the Linear Solvation Energy Relationships Using the Solvatochromic Parameters for Mobile Phases, ${\pi}_m^{\ast}, {\alpha}_m$ and ${\beta}_m$

  • Park, Jung-Hag;Jang, Myung-Duk;Kim, Sang-Tae
    • Bulletin of the Korean Chemical Society
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    • 제11권4호
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    • pp.297-302
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    • 1990
  • Retention of mono-substituted phenols in reversed-phase liquid chromatography has been studied based on the linear solvation energy relationships using the solvatochromic mobile phase parameters, ${\pi}_m^{\ast}, {\alpha}_m$ and ${\beta}_m$. It has been observed that retention behavior of phenols in RPLC were well represented by regression equations vs. solvatochromic mobile phase parameters even though the equations may be incomplete due to lack of an explicit cavity term. Dependence of retention of monosubstituted phenols on the mobile phase properties were varied depending on the type of the organic cosolvent in the mobile phase, e.g., ${\beta}_m$ and {\alpha}_m$ in methanol-water system, but ${\pi}_m^{\ast} and ${\beta}_m$ in THF-water system. It has been suggested that retention of phenols in methanol-water system is controlled by the solvophobicity of the mobile phase.

Hispidin from the Mycelial Cultures of Phellinus linteus Inhibits A $\beta$-Secreatase(BACE1) and proyl endopeptidase

  • Park, In-Hye;Kim, Sang-In;Jeon, So-Young;Lee, Hee-Ju;Song, Kyung-Sik
    • 대한약학회:학술대회논문집
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    • 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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    • pp.271.2-271.2
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    • 2003
  • The ${\gamma}$- and ${\beta}$-secretase are one of the most important proteases, which cleave amyloid precursor protein (APP) into neurotoxic A${\beta}$ peptide in Azheimer's type dementia. In the course of screening for anti-dementia agents from natural products, the mycelial culture of mushroom Phellinus linteus showed potent inhibition againt ${\beta}$-secretase (BACE1). (omitted)

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Enhancement of Sensitivity in Interferometric Biosensing by Using a New Biolinker and Prebinding Antibody

  • Park, Jae-Sook;Lim, Sung-Hyun;Sim, Sang-Jun;Chae, Hee-Yeop;Yoon, Hyun-C.;Yang, Sang-Sik;Kim, Byung-Woo
    • Journal of Microbiology and Biotechnology
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    • 제16권12호
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    • pp.1968-1976
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    • 2006
  • Recombinant E. coli ACV 1003 (recA:: lacZ) was used to measure low concentrations of DNA-damaging chemicals, which produce $\beta$-galactosidase via an SOS regulon system. Very low $\beta$-galactosidase activities of less than 0.01 unit/ml, $\beta$-galactosidase produced through an SOS response corresponding to the 10 ng/ml (ppb) of DNA damaging chemicals in the environment, can be rapidly determined by using an alternative interferometric biosensor with optically flat thin films of porous silicon rather than by the conventional time-consuming Miller's enzyme assay as well as the ELISA method. fu order to enhance the sensitivity in the interferometry, it needs to obtain more uniform distribution and higher biolinking efficiency, whereas interferometric sensing is rapid, cheap, and advantageous in high throughput by using a multiple-well-type chip. In this study, pore size adjusted to 60 nm for the target enzyme $\beta$-galactosidase to be bound on both walls of a Si pore and a calyx crown derivative was apllied as a more efficient biolinker. Furthermore, anti-$\beta$-galactosidase was previously functionalized with the biolinker for the target $\beta$-galactosidase to be specifically bound. When anti-$\beta$-galactosidase was bound to the calyx-crown derivative-linked surface, the effective optical thickness was found to be three times as high as that obtained without using anti-$\beta$-galactosidase. The resolution obtained was very similar to that afforded by the time-consuming ELISA method; however, the reproducibility was still unsatisfactory, below 1 unit $\beta$-galactosidase/ml, owing to the microscopic non-uniform distribution of the pores in the etched silicon surface.

$\beta$-glucosidase의 고정화와 효소 반응특성 (Immobilization of $\beta$-glucosidase and properties of Immobilized Enzyme)

  • 정의준;이상호이용현
    • KSBB Journal
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    • 제5권2호
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    • pp.141-149
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    • 1990
  • Aspergillus niger유래의 $\beta$-glucosidase를 (1)glutarald-ehyde를 가교제로 한 chitin과 chitosan담체에 covalent linkage (2)Amberite IRA93과 DEAE-cellulose담체에 succinylation시킨 후 흡착, 그리고 (3)alginarte, polyacry-lamide를 각종 가교제를 이용 entrapment등의 방법으로 고정화 하였다. Glutaraldehyde를 가교제로써 chitosan을 활성화시킨후 $\beta$-glucosidase를 고정화 시켰을때 효소활성 회수율이 31.5%로 가장 높았고, 또한 column형 반응기에서의 15일 경과 후 효소활성 유지도도 69%로서 가장 우수하였다. 또한 succinylation시킨 효소를 Amberite IRA93 담체에 흡착시켰을 때 효소활성 회수율은 24.7%였고 효소 활성유지도는 62%였다. 반면에 entra-pment 방법에 의한 $\beta$-glucosidase의 고정화는 효소의 계속적인 용출로 $\beta$-glucosidase의 고정화에는 적합하지 않았다. Chitosan담체에서의 고정화 최적조건을 조사한 결과 가교제인 glutaraldehyde의 최적농도는 0.4%였고, glutaraldehyde의 최적 반응 pH는 4.8이었다. 또한 column형 반응기를 이용하여 cellobiose로부터 glucose로의 전환율을 조사하여 고정화 효소의 효용성을 검토하였다.

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비만 중년 남성의 비만 유형별 체질량지수와 인슐린저항성 및 베타세포 기능간의 관련성 (Relationship between Body Mass Index and Insulin Resistance and Beta Cell Function by Obesity Type in Obese Middle-Aged Men)

  • 신경아
    • 한국융합학회논문지
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    • 제11권10호
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    • pp.155-162
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    • 2020
  • 이 연구는 비만 중년 남성을 대상으로 복부비만 유무에 따른 체질량지수와 인슐린저항성 및 베타세포 기능간의 관련성을 알아보고자 하였다. 2018년 1월부터 2020년 6월까지 경기도 소재 종합병원에서 건강검진을 받은 비만 중년 남성 797명을 대상으로 하였다. 복부비만 동반군은 327명, 복부비만을 동반하지 않은군은 470명이며, 두 군간에 공복혈당(p<0.001), HbA1c(p=0.003), 인슐린(p<0.001), HOMA-IR(p<0.001)은 차이가 있었다. 체질량지수는 복부비만 동반 유무와 관계없이 인슐린저항성 및 베타세포 기능에 영향을 미치는 요인이었다. 또한 체질량지수는 복부비만 동반 유무와 관계없이 인슐린저항성 및 베타세포 기능저하의 질환 발병과 관련이 있었다. 따라서 중년 비만 남성의 건강관리를 위한 운동 프로그램 수행 및 정기적인 검진을 통해 체질량지수의 지표 관리가 필요할 것으로 사료된다.