• Title/Summary/Keyword: Composite fraction

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Biological Activities or oat soluble $\beta$-glucans (귀리 수용성 $\beta$-glucan의 생물활성)

  • 강태수;정헌상;박희정;이명렬;공영준;정익수
    • Food Science and Preservation
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    • v.10 no.4
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    • pp.547-553
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    • 2003
  • To develop the health and functional food material from oats, this study was conducted to determine the biologiral activities(antibacterial, antioxidative and mtltmor effects) of oat bran's soluble ${\beta}$-glucans obtained from oat bran concentrate(OBC) by central composite experimental design. The antibacterial effect of oat's ${\beta}$-glucans in the concentration of 250, 500$\mu\textrm{g}$/disc was not detected by paper disc method, and no antioxidative effect of them in the concentration of 5% by electron donating ability. The growth inhibition on tumor cell lines of oat's soluble ${\beta}$ -glucans was significantly higher in the experimental fraction of No. 7(temperature 45$^{\circ}C$, ethanol 15%, pH 6) than the other fractions(p<0.05). The maximal values of growth inhibitions on AGS, Hep3B and A549 cell lines in the cancentration of 1mg/ml are 59%, 58% and 54% respectively. In addition, the inhibition effect on three tumor cell lines of No. 1(temperature 5$^{\circ}C$, ethanol 5%, pH 6) was relatively high. From the results of response surface methodology, as the values of independent variables changed, they influenced the growth inhibition effect on this cell lines. With this on work further research is required to clarify antitumor effects.

Use of waste steel fibers from CNC scraps in shear-deficient reinforced concrete beams

  • Ilker Kalkan;Yasin Onuralp Ozkilic;Ceyhun Aksoylu;Md Azree Othuman Mydin;Carlos Humberto Martins;Ibrahim Y. Hakeem;Ercan Isik;Musa Hakan Arslan
    • Steel and Composite Structures
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    • v.49 no.2
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    • pp.245-255
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    • 2023
  • The present paper summarizes the results of an experimental program on the influence of using waste lathe scraps in the concrete mixture on the shear behavior of RC beams with different amounts of shear reinforcement. Three different volumetric ratios (1, 2 and %3) for the scraps and three different stirrup spacings (160, 200 and 270 mm) were adopted in the tests. The shear span-to-depth ratios of the beams were 2.67 and the stirrup spacing exceeded the maximum spacing limit in the building codes to unfold the contribution of lathe scraps to the shear resistances of shear-deficient beams, subject to shear-dominated failure (shear-tension). The experiments depicted that the lathe scraps have a pronounced contribution to the shear strength and load-deflection behavior of RC beams with widely-spaced stirrups. Namely, with the addition of 1%, 2% and 3% waste lathe scraps, the load-bearing capacity escalated by 9.1%, 21.8% and 32.8%, respectively, compared to the reference beam. On the other hand, the contribution of the lathe scraps to the load capacity decreases with decreasing stirrup spacing, since the closely-spaced stirrups bear the shear stresses and render the contribution of the scraps to shear resistance insignificant. The load capacity, deformation ductility index (DDI) and modulus of toughness (MOT) values of the beams were shown to increase with the volumetric fraction of scraps if the stirrups are spaced at about two times the beam depth. For the specimens with a stirrup spacing of about the beam depth, the scraps were found to have no considerable contribution to the load capacity and the deformation capacity beyond the ultimate load. In other words, for lathe scrap contents of 1-3%, the DDI values increased by 5-23% and the MOT values by 63.5-165% with respect to the reference beam with a stirrup spacing of 270 mm. The influence of the lathe scraps to the DDI and MOT values were rather limited and even sometimes negative for the stirrup spacing values of 160 and 200 mm.

New Method for Combined Quantitative Assessment of Air-Trapping and Emphysema on Chest Computed Tomography in Chronic Obstructive Pulmonary Disease: Comparison with Parametric Response Mapping

  • Hye Jeon Hwang;Joon Beom Seo;Sang Min Lee;Namkug Kim;Jaeyoun Yi;Jae Seung Lee;Sei Won Lee;Yeon-Mok Oh;Sang-Do Lee
    • Korean Journal of Radiology
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    • v.22 no.10
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    • pp.1719-1729
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    • 2021
  • Objective: Emphysema and small-airway disease are the two major components of chronic obstructive pulmonary disease (COPD). We propose a novel method of quantitative computed tomography (CT) emphysema air-trapping composite (EAtC) mapping to assess each COPD component. We analyzed the potential use of this method for assessing lung function in patients with COPD. Materials and Methods: A total of 584 patients with COPD underwent inspiration and expiration CTs. Using pairwise analysis of inspiration and expiration CTs with non-rigid registration, EAtC mapping classified lung parenchyma into three areas: Normal, functional air trapping (fAT), and emphysema (Emph). We defined fAT as the area with a density change of less than 60 Hounsfield units (HU) between inspiration and expiration CTs among areas with a density less than -856 HU on inspiration CT. The volume fraction of each area was compared with clinical parameters and pulmonary function tests (PFTs). The results were compared with those of parametric response mapping (PRM) analysis. Results: The relative volumes of the EAtC classes differed according to the Global Initiative for Chronic Obstructive Lung Disease stages (p < 0.001). Each class showed moderate correlations with forced expiratory volume in 1 second (FEV1) and FEV1/forced vital capacity (FVC) (r = -0.659-0.674, p < 0.001). Both fAT and Emph were significant predictors of FEV1 and FEV1/FVC (R2 = 0.352 and 0.488, respectively; p < 0.001). fAT was a significant predictor of mean forced expiratory flow between 25% and 75% and residual volume/total vital capacity (R2 = 0.264 and 0.233, respectively; p < 0.001), while Emph and age were significant predictors of carbon monoxide diffusing capacity (R2 = 0.303; p < 0.001). fAT showed better correlations with PFTs than with small-airway disease on PRM. Conclusion: The proposed quantitative CT EAtC mapping provides comprehensive lung functional information on each disease component of COPD, which may serve as an imaging biomarker of lung function.