• Title/Summary/Keyword: STM

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Effect of Sugar Kind Added in Tris-buffer on Acrosome Damage of Post-thaw Spermatozoa in Canine (Tris-buffer에 첨가되는 당의 종류가 동결.융해정자의 첨체 손상에 미치는 영향)

  • 유대중;공일근
    • Journal of Embryo Transfer
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    • v.18 no.2
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    • pp.91-96
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    • 2003
  • The aim of this study was conducted to evaluate the effect of sugar kinds and combination of various sugars on acrosome damage of post-thaw spermatozoa in canine. The extender used in this study was Tris-citric acid extender (Tris-buffer) supplemented with 20% Egg-yolk, 8% glycerol, 1% Equex STM paste, and 70 mM sugars such as monosaccharide (fructose and xylose) and disaccharide(trehalose). To evaluate of sugar combination, the sugars supplemented in Tris-buffer were combined such as control (fructose, xylose, trehalose), two combinations (Fru+Tre, Fru+Xyl, Tre+Xyl) and three combinations (Fru+Tre+Xyl). The acrosome damage rate of post-thaw spermatozoa in Eosin B & Fast Green stain in Fruc+Tre was higher than those in fructose, trehalose, xylose, Fruc+Xyl, Tre+Xyl, Fruc+Tre+Xyl (83.0$\pm$5.6 vs. 82.3$\pm$3.1%, 81.7$\pm$2.1%, 72.0$\pm$2.0%; 80.3$\pm$4.5%, 76.7$\pm$3.8%, 81.0$\pm$5.6). The motility after CASA analysis in Fru+Tre was higher than those in Fru+Tre+Xyl, Tre+Xyl, Fru+Xyl, Xylose, Trehalose, Fructose(79$\pm$6 vs 75$\pm$3, 74$\pm$8, 71$\pm$11, 70$\pm$4, 66$\pm$15, 63$\pm$ 12%). However, the progressive motility after CASA analysis in Fru+Tre group was higher than those in Fru+Tre+Xyl, Tre+Xyl, Fru+Xyl, Xylose, Trehalose, Fructose (67$\pm$7, 64$\pm$3, 62$\pm$6, 61$\pm$8, 60$\pm$2, 57$\pm$13, 53$\pm$10%). The results indicated that the acrosome damage & progressive motility of post-thaw spermatozoa in 70 mM Fruc+Tre (two combination) following Eosin B & Fast Green stain and CASA analysis.

Development of Optimum Grip System in Developing Design Tensile Strength of GFRP Rebars (GFRP 보강근의 설계 인장강도 발현을 위한 적정 그립시스템 개발)

  • You Young-Chan;Park Ji-Sun;You Young-Jun;Park Young-Hwan;Kim Keung-Hwan
    • Journal of the Korea Concrete Institute
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    • v.17 no.6 s.90
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    • pp.947-953
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    • 2005
  • Previous test results showed that the current ASTM(American Standard for Testing and Materials) grip adapter for GFRP(Glass Fiber Reinforced Polymer) rebar was not fully successful in developing the design tensile strength of GFRP rebars with reasonable accuracy. It is because the current ASTM grip adapter which is composed of a pair of rectangular metal blocks of which inner faces are grooved along the longitudinal direction does not take into account the various geometric characteristics of GFRP rebar such as surface treatment, shape of bar cross section as well as physical characteristics such as poisson effect, elastic modulus in the transverse direction and so on. The objective of this paper is to provide how to proportion the optimum diameter of inner groove in ASTM grip adapter to develop design tensile strength of GFRP rebar. The proportioning of inner groove in ASTM grip adapter is based on the force equilibrium of GFRP rebar between tensile capacity and minimum frictional resistance required along the grip adapter. The frictional resistance of grip adapter is calculated based on the compressive strain compatibility in radial direction induced by the difference between diameter of GFRP rebar and inner groove In ASTM grip. All testing procedures were made according to the CSA S806-02 recommendations. From the preliminary test results on round-type GFRP rebars, it was found that maximum tensile loads acquired under the same testing conditions is highly affected by the diameter of inner groove in ASTM grip adapter. The grip adapter with specific dimension proportioned by proposed method recorded the highest tensile strength among them.