• Title/Summary/Keyword: confocal laser scanning microscope (CLSM)

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A confocal microscopic study of dentinal infiltrations in one-bottle adhesive systems bonded to Class V cavities

  • Kim, Hyung-Su;Park, Sung-Ho
    • Proceedings of the KACD Conference
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    • 2001.11a
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    • pp.576.2-576
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    • 2001
  • The purpose of this study was to evaluate the effect of dentinal sclerosis and tubular orientation on Class V restoration bonded with three dentin bonding agents using confocal laser scanning microscope(CLSM). Class V cavities were prepared from freshly extracted caries-free human teeth. thirty of these cavities were divided into two groups based upon the status of class V cavities: Group 1, cervical abrasive lesions without preparation; Group 2, artificially-prepared wedge-shaped cavities.(omitted)

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CLSM [Confocal Laser Scanning Microscope] Observation of the Surface Roughness of Pressurized Rock Samples During Freeze/Thaw Cycling

  • Kim, Hye-jin;Choi, Junghae;Chae, Byung-gon;Kim, Gyo-won
    • The Journal of Engineering Geology
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    • v.25 no.2
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    • pp.165-178
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    • 2015
  • Physical and chemical weathering degrades rock, affecting its structural properties and thus the stability of stone buildings or other structures. Confocal laser scan microscopy (CLSM) is used here to observe temporal changes in the surface roughness of rock samples under simulated accelerated weathering. Samples were pressurized to 50, 55, or 70 MPa using a pressure frame, and subjected to freeze/thaw cycling controlled by a thermostat. The temperature was cycled from -20℃ to 40℃ and back. After each 20 cycles, CLSM was used to assess the change in surface roughness, and roughness factors were calculated to quantify the progression of the surface condition over time. Variations in cross-section line-roughness parameters and surface-roughness parameters were analyzed for specific parts of the sample surfaces at 5× and 50× magnification. The result reveals that the highest and lowest values of the roughness factors are changed according to elapsed time. Freezing/thawing at high pressure caused larger changes in the roughness factor than at low pressure.

A Study of Roughness Measurement of Rock Discontinuities Using a Confocal Laser Scanning Microscope (콘포컬 레이저 현미경을 이용한 불연속면의 거칠기 측정 연구)

  • Byung Gon Chae;Jae Yong Song;Gyo Cheol Jeong
    • The Journal of Engineering Geology
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    • v.12 no.4
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    • pp.405-419
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    • 2002
  • Fracture roughness of rock specimens is observed by a new confocal laser scanning microscope (CLSM; Olympus OLS1100). The wave length of laser is 488 nm, and the laser scanning is managed by a light polarization method using two galvano-meter scanner mirrors. The function of laser reflection auto-focusing enables us to measure line data fast and precisely. The system improves resolution in the light axis (namely z) direction because of the confocal optics. Using the CLSM, it is Possible to measure a specimen of the size up to $10{\;}{\times}{\;}10{\;}cm$ which is fixed on a specially designed stage. A sampling is managed in a spacing $2.5{\;}\mu\textrm{m}$ along x and y directions. The highest measurement resolution of z direction is $10{\;}\mu\textrm{m}$, which is more accurate than other methods. Core specimens of coarse and fine grained granite are provided. Fractures are artificially maneuvered by a Brazilian test method. Measurements are performed along three scan lines on each fracture surface. The measured data are represented as 2-D and 3-D digital images showing detailed features of roughness. Line profiles of the coarse granites represent more frequent change of undulation than those of the fine granite. Spectral analyses by the fast Fourier transform (FFT) are performed to characterize the roughness data quantitatively and to identify influential frequency of roughness. The FFT results suggest that a specimen loaded by large and low frequency energy tends to have high values of undulation change and large wave length of fracture roughness.

The Changes of Aperture Variation and Hydraulic Conductivity for Compression Variability (압력에 따른 균열 간극변화와 수리전도도 변화 관찰)

  • 채병곤;이철우;정교철;김용제
    • Journal of Soil and Groundwater Environment
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    • v.8 no.4
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    • pp.1-11
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    • 2003
  • In order to measure aperture variation dependent on normal stress and to characterize on relationship between aperture variation and hydraulic conductivity this study measured apertures of rock fractures under a high resolution confocal laser scanning microscope (CLSM) with application of five stages of uniaxial normal stresses. From this method the response of aperture can be continuously characterized on one specimen by different loads of normal stress. The results of measurements showed a rough geometry of fracture bearing non-uniform aperture. They also revealed different values of aperture variations according to the load stages on each position along a fracture due to the fracture roughness. Laboratory permeability tests were also conducted to evaluate the changes of permeability coefficients related to the aperture variations by different loads. The results of permeability tests revealed that the hydraulic conductivity was not reduced at a fixed rate with increase of normal load. Moreover, the rates of aperture variations did not match to those of hydraulic conductivity. The hydraulic conductivity calculated in this study did not follow the cubic law, representing that the parallel plate model is not suitable to express the fracture geometry corresponding to the results of aperture measurements under the CLSM.

Study of Morphology and Physical Properties of Indian Mallow(Abutilon avicennae Gaertner) Fibers by CLSM( I ) (CLSM을 이용한 어저귀 섬유의 형태학적 특성과 물성 연구(제1보) -인피 및 목질부 섬유를 이용한 한지제조-)

  • 정선화;조남석
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.34 no.2
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    • pp.61-66
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    • 2002
  • This study was carried out to investigate sheet properties of Indian mallow hanji, made by different pulping methods such as alkali and sulfomethylated pulpings, and different stock compositions, various mixing ratios of bast fiber and woody core fibers. Effect of morphological properties of pulp stocks on the sheet formation and their optical properties were also evaluated using an image analyzer and confocal laser scanning microscope(CLSM). In addition, the effect of fiber distribution index(FDI), which was calculated based on the image in a z-direction of a sheet from CLSM, on the sheet properties of Indian mallow hanji was discussed. The proposed FDI had a good correlation with various properties of paper, such as apparent density, opacity, tear index, breaking length and zero-span tensile strength. Especially, sulfomethylated pulp sheets'FDI was higher than alkali pulp sheets.

Application of Confocal Laser Scanning Microscopy and Fiber Distribution Index to Study Kenaf Handsheet Properties

  • Pang, Myong-Hyeok;Park, Jong-Moon;Cho, Nam-Seok
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.31 no.3
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    • pp.54-59
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    • 1999
  • This study was to quantify fiber distributions in thickness direction of kenaf handsheets as a fiber distribution index (FDI) and to analyze the relationship between FDI and the handsheet properties. The images of fiber distribution in z-direction were obtained by Confocal Laser Scanning Microscope (CLSM) and analyzed by image analysis technique. The proposed FDI had a good correlation with high R2 vlaues with various properties of paper, such as apparent density, scattering coefficient , burst index, tear index, tensile index, and folding endurance. The proposed FDI was shown as a good index to quantify paper properties.

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THE ADHESIVE PATTERNS OF COMPOMER TO SALIVA-CONTAMINATED DENTIN (타액에 오염된 상아질에 대한 콤포머의 접합양상)

  • Cho, Young-Gon;Kim, Byung-Tae;Lee, Suk-Jong
    • Restorative Dentistry and Endodontics
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    • v.25 no.4
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    • pp.575-586
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    • 2000
  • In this study, adaptation of compomer to saliva contaminated dentin was evaluated with scanning electron microscope(SEM) and confocal laser scanning microscope(CLSM). For the SEM study, the occulusal surfaces of thirty two molar teeth were grounded to exposure dentin surfaces. The specimen were randomly assigned to control and three experimental groups with four samples in each group. In control group, Dyract and F-2000 compomer were bonded on the specimens according to the manufactures direction. Experimental groups were subdivided into three groups. They were contaminated with saliva on dentin surfaces ; Experimental group 1 : Saliva was dried with compressed air. Experimental group 2 : Saliva was rinsed with air-water spray and dried. Experimental group 3 : After polymerization of an adhesive, they were contaminated with saliva, and then saliva was rinsed with air-water spray and dried. Dyract and F-2000 compomer were bonded on saliva-treated dentin surfaces. The interfaces between dentin and compomer were observed with SEM. For the CLSM study, Class V cavities were prepared in buccal and ligual surfacess of thirty two molars. The specimens were divided into control and experimental groups. Class V cavities in experimental group were contaminated with saliva and those surfaces in each experimental groups received the same treatments as for the SEM study. Cavities were applied Prime & Bond 2.1 and F-2000 compomer primer/adhesive that were mixed with fluorescein, and then were filled with Dyract and F-2000 compomer. Specimens were embedded in transparent acrylic resin and sectioned buccolingual1y with diamond wheel saw, and then mounted on cover slide for CLSM study. The interface between cavity and compomer was observed by fluoresence imaging with a CLSM. The results were as follows : 1. In SEM exammination of Dyract group, control group, experimental group 2, 3 showed close adaptation to dentin and hybrid layer of $3{\sim}4{\mu}m$ diameter. Interfacial gap between compomer and dentin in experimental group 1 was wider than in control group. 2. In SEM examination of F-2000 group, adaptation to dentin of control group was closer than Dytact control group, but hybrid-like layer was not observed. Interfacial gap between compomer and dentin in experimental group 1 was wider than in Dyract experimental group 1. 3. In dissolution specimens of Dyract and F-2000 group, resin tags penetrated through dentinal tubules in control group and experimental group 1 and 3, but the penetration of resin tag was irregular and partial in experimental group 1. 4. In CLSM exammination of Dyract and F-2000 group, adhesive patterns of control and experimental groups showed same as in SEM. This result suggests the treatment methods, rinsing & drying, repeating all adhesive procedures, will produce good effect on adaptation of compomer to dentin if the dentin surface or polymerized adhesive is contaminated by saliva.

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In Vivo Evaluation of Multi Lamellar Vesicle Liposome’s Percutaneous Absorption and Stability

  • Joung, Min-Seok;Park, Jong-Oan;Seo, Bong-Seok;Ryu, Chang-Duck
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.27 no.1
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    • pp.29-42
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    • 2001
  • We had prepared MLV liposome with Hibiscus Esculentus Ext.(HEE) which have fluorescent light in order to evaluate its percutaneous absorption about hairless rat skin. Then we investigated particle size of MLV using confocal laser scanning microscope(CLSM) and transmission electron microscope(TEM), respectively. Stability of MLV liposome and penetration of MLV liposome to hairless rat skin was measured by CLSM. As a result of experiments, MLV was globular shape and the rage of particle size was 0.3-0.5$\mu\textrm{m}$ mostly. Cream-type MLV had high stability comparatively. When we treated with MLV to rat skin, skin penetration was enhanced, especially, the optimum concentration of MLV on penetration to rat skin was 10%. Optimum penetration time was 6hr-12hr. And MLV-type HEE was more effective on percutaneous absorption than HEE-cream or liposome-type HEE.

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Autofluorescence of artificial incipient root carious lesions

  • Lee, Hyeong-Mo;Park, Jeong-Kil;Hur, Bock
    • Proceedings of the KACD Conference
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    • 2003.11a
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    • pp.615-615
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    • 2003
  • I. Objectives This study was performed to get some information about micromorphology of subsurface lesion of root caries by observing autofluorescence using confocal laser scanning microscope(CLSM) with minimum sample preparation. II. Materials and Methods Half-cut and 1 mm thick sample of human teeth were prepared to produce artificial root carious lesions. Incipient subsurface lesions were produced under optimal pH and saturity. The lesions were observed by polarized microscopy, CLSM, and back-scattered electron microscope(BSE). Calcium and phosphorus concentrations of the lesions were analyzed by line EDAX. (omitted)

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A STUDY OF THE PRESSURE SOLUTION AND DEFORMATION OF QUARTZ CRYSTALS AT HIGH pH AND UNDER HIGH STRESS

  • Choi, Jung-Hae;Seo, Yong-Seok;Chae, Byung-Gon
    • Nuclear Engineering and Technology
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    • v.45 no.1
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    • pp.53-60
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    • 2013
  • Bentonite is generally used as a buffer material in high-level radioactive waste disposal facilities and consists of 50% quartz by weight. Quartz strongly affects the behavior of bentonite over very long periods. For this reason, quartz dissolution experiment was performed under high-pressure and high-alkalinity conditions based on the conditions found in a high-level radioactive waste disposal facility located deep underground. In this study, two quartz dissolution experiments were conducted on 1) quartz beads under low-pressure and high-alkalinity conditions and 2) a single quartz crystal under high-pressure and high-alkalinity conditions. Following the experiments, a confocal laser scanning microscope (CLSM) was used to observe the surfaces of experimental samples. Numerical analyses using the finite element method (FEM) were also performed to quantify the deformation of contact area. Quartz dissolution was observed in both experiments. This deformation was due to a concentrated compressive stress field, as indicated by the quartz deformation of the contact area through the FEM analysis. According to the numerical results, a high compressive stress field acted upon the neighboring contact area, which showed a rapid dissolution rate compared to other areas of the sample.