• Title/Summary/Keyword: Basic Science

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Experimental Evaluation of Mechanical Properties for the Carbon/Epoxy Composite Laminates at Low Temperature (탄소섬유/에폭시 복합적층판에 대한 저온에서의 기계적특성 실험평가)

  • Her, N.I.;Sa, J.W.;Cho, S.;Do, C.J.;Oh, Y.K.;Choi, C.H.;Kwon, M.;Lee, G.S.;Lee, S.Y.;Kim, J.H.
    • Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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    • 2001.02a
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    • pp.41-44
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    • 2001
  • Mechanical test of the Carbon Fiber Reinforced Plastics (CFRP) composite specimen was performed based on the ASTM code at the ambient and low temperature. Tension, compression in-plane shear, and inter-laminar shear properties of the composite laminates were evaluated experimentally using the Universal Testing Machine(UTM) system at the temperature of $24^{\circ}C$,$-76^{\circ}C$ , and $-196^{\circ}C$. From the test results it was found that the CFRP chosen for the Korea Superconducting Tokamak Advanced Research(KSTAR) magnet supporting post had smaller tensile strength and larger compressive strength at the low temperature than those of the ambient temperature because of material ductility.

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Ultrastructural Abnormalities in APP/PSEN1 Transgenic Mouse Brain as the Alzheimer's Disease Model

  • Kim, Mi Jeong;Huh, Yang Hoon;Choi, Ki Ju;Jun, Sangmi;Je, A Reum;Chae, Heesu;Lee, Chulhyun;Kweon, Hee-Seok
    • Applied Microscopy
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    • v.42 no.4
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    • pp.179-185
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    • 2012
  • Alzheimer's disease (AD) is a progressive neurodegenerative disorder. Neuropathological hallmarks of AD are amyloid plaques, dystrophic neurite, and alteration of subcellular organelles. However, the morpho-functional study of this degenerative process and ultimate neuronal death remains poorly elucidated. In this study, immunohistochemical and ultrastructural analyses were performed to clarify the abnormal morphological alterations caused by the progression of AD in APP/PSEN1 transgenic mice, express human amyloid precursor protein, as a model for AD. In transgenic AD mice brain, the accumulation of Amyloid ${\beta}$ plaques and well-developed dystrophic neurites containing anti-LC3 antibody-positive autophagosomes were detected in the hippocampus and cortex regions. We also found severe disruption of mitochondrial cristae using high-voltage electron microscopy and three-dimensional electron tomography (3D tomography). These results provide morpho-functional evidence on the alteration of subcellular organelles in AD and may help in the investigation of the pathogenesis of AD.