• 제목/요약/키워드: Force Spectroscopy

검색결과 514건 처리시간 0.032초

Label-free Noninvasive Characterization of Osteoclast Differentiation Using Raman Spectroscopy Coupled with Multivariate Analysis

  • Jung, Gyeong Bok;Kang, In Soon;Lee, Young Ju;Kim, Dohyun;Park, Hun-Kuk;Lee, Gi-Ja;Kim, Chaekyun
    • Current Optics and Photonics
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    • 제1권4호
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    • pp.412-420
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    • 2017
  • Multinucleated bone resorptive osteoclasts differentiate from bone marrow-derived monocyte/macrophage precursor cells. During osteoclast differentiation, mononuclear pre-osteoclasts change their morphology and biochemical characteristics. In this study, Raman spectroscopy with multivariate techniques such as Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA) were used to extract biochemical information related to various cellular events during osteoclastogenesis. This technique allowed for label-free and noninvasive monitoring of differentiating cells, and clearly discriminated four different time points during osteoclast differentiation. The Raman band intensity showed significant time-dependent changes that increased up to day 4. The results of Raman spectroscopy agreed with results from atomic force microscopy (AFM) and tartrate-resistant acid phosphatase (TRAP) staining, a conventional biological assay. Under AFM, normal spindle-like mononuclear pre-osteoclasts became round and smaller at day 2 after treatment with a receptor activator of nuclear $factor-{\kappa}B$ ligand and they formed multinucleated giant cells at day 4. Thus, Raman spectroscopy, in combination with PCA-LDA, may be useful for noninvasive label-free quality assessment of cell status during osteoclast differentiation, enabling more efficient optimization of the bioprocesses.

Indium tin oxide 기판의 표면처리에 따른 유기 발광다이오드의 특성 (Performance of Organic light-emitting diode by various surface treatments of indium tin oxide)

  • 김선혁;한정환
    • 대한전자공학회논문지SD
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    • 제39권9호
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    • pp.1-10
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    • 2002
  • 유기 발광 다이오드를 위한 indium oxide (ITO) 기판을 여러 가지로 방법으로 표면처리를 하고, 이에 따른 atomic force microscopy (AFM)에 의한 morphology의 변화와 표면에서 변화된 원소들의 조성비를 Auger electron spectroscopy (AES)분석에 의하여 조사하였다. 또한 이 기판을 사용하여 초고진공분자선 증착방법에 의하여 유기 발광다이오드를 제작하고 그 특성을 조사하였다. 그 결과 산소플라즈마으로 표면 처리한 ITO 기판 위에 제조된 organic light-emitting diode (OLED)소자의 특성이 향상되었다. 그것은 AES의 분석에 의하면 ITO 표면의 오염된 탄소가 제거되고 ITO의 일함수가 증가되어 정공이 유기물 층으로 용이하게 주입한 결과로 판단된다.

광디스크의 노화에 관한 주사 탐침 현미경 연구 (Scanning Probe Microscopy Study on the Degradation of Optical Recoding Disks by Environmental Factors)

  • 윤만영;신현창
    • 한국인쇄학회지
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    • 제29권3호
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    • pp.97-104
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    • 2011
  • The storing ability of information of optical disks directly depends on the physical property of recording unit cells. It means that the degradation of optical disks ultimately causes the loss of the physical and chemical properties of recording unit cells and leads also information, too. We investigated the degradation and life time of optical disks which tell us the longevity of the preservation of information. Optical disks were aged using the accelerated aging system and studied by optical reflectivity spectroscopy and atomic force microscopy(AFM), and the preservation environment of electronic media in National central library of Korea also were analysed. Results show that the double reflective coated optical disks have good preservation of recording information but revealed some deformation of dye area in the AFM images. It means that we should include the mechanical and chemical degradation of the optical disks in the life time expectation evaluation.

Multiplexed single-molecule flow-stretching bead assay for DNA enzymology

  • Lee, Ryanggeun;Yang, Keunsang;Lee, Jong-Bong
    • BMB Reports
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    • 제52권10호
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    • pp.589-594
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    • 2019
  • Single-molecule techniques have been used successfully to visualize real-time enzymatic activities, revealing transient complex properties and heterogeneity of various biological events. Especially, conventional force spectroscopy including optical tweezers and magnetic tweezers has been widely used to monitor change in DNA length by enzymes with high spatiotemporal resolutions of ~nanometers and ~milliseconds. However, DNA metabolism results from coordination of a number of components during the processes, requiring efficient monitoring of a complex of proteins catalyzing DNA substrates. In this min-review, we will introduce a simple and multiplexed single-molecule assay to detect DNA substrates catalyzed by enzymes with high-throughput data collection. We conclude with a perspective of possible directions that enhance capability of the assay to reveal complex biological events with higher resolution.

Arnoldi Algorithm for the Simulation of Multidimensional Infrared Spectroscopy

  • Hayashi, Tomoyuki;Mukamel, Shaul
    • Bulletin of the Korean Chemical Society
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    • 제24권8호
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    • pp.1097-1101
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    • 2003
  • The cubic and quartic anharmonic force field of malonaldehyde is calculated using density functional theory at the B3LYP/6-31G(d,p) level, and used to simulate coherent infrared vibrational spectra. 12 normal modes are included in the simulation, and the Arnoldi method is employed for the diagonalization of the Hamiltonian. The calculated three pulse infrared signals in the k1 + k2 - k3 direction show signatures of the intramolecular hydrogen bond couplings between the C=O stretch, H-O-C bend and O-H stretch vibrations.

Merocyanine dye LB막의 표면이미지 및 광학적 특성 연구 (Study on morphology and OPtical Characteristics of merocyanine dye LB films)

  • 류길용;박상현;박재철;권영수
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 추계학술대회 논문집 전기물성,응용부문
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    • pp.136-138
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    • 2005
  • Merocyanine dye (MD) has been extensively investigated due to its marked potential application to photo-electric devices. We fabricated the number of layers to control its optical characteristics using the Langmuir-Blodgett (LB) method. We evaluated the morphology and optical characteristics of MD LB films using Atomic Force Microscopy (AFM) and UV spectroscopy, PL spectroscopy. As a result, we obtained the quantitative morphology and optical characteristics of LB films from controlling the deposided layers.

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혼성복합재료의 계면 특성 분석 (Characterization of Interface in Hybrid Composites)

  • 하창식;안기열;조원재
    • 접착 및 계면
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    • 제1권1호
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    • pp.47-55
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    • 2000
  • In this article, the characterization of the interface of hybrid composites was discussed. Interfacial interaction in organic/inorganic hybrid composites, especially silica-containing hybrids can be characterized by fluorescence spectroscopy, small angle X-ray scattering (SAXS), scanning electron microscopy (SEM), atomic force microscopy (AFM), and $^{29}Si$ NMR spectroscopy measurements.

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Cl2/BCl3/Ar 플라즈마에서 반응성 이온들에 의해 식각된 ZnO 박막 표면 연구 (A Study of the Etched ZnO Thin Films Surface by Reactive Ion in the Cl2/BCl3/Ar Plasma)

  • 우종창;김창일
    • 한국전기전자재료학회논문지
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    • 제23권10호
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    • pp.747-751
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    • 2010
  • In the study, the characteristics of the etched Zinc oxide (ZnO) thin films surface, the etch rate of ZnO thin film in $Cl_2/BCl_3/Ar$ plasma was investigated. The maximum ZnO etch rate of 53 nm/min was obtained for $Cl_2/BCl_3/Ar$=3:16:4 sccm gas mixture. According to the x-ray diffraction (XRD) and atomic force microscopy (AFM), the etched ZnO thin film was investigated to the chemical reaction of the ZnO surface in $Cl_2/BCl_3/Ar$ plasma. The field emission auger electron spectroscopy (FE-AES) analysis showed an elemental analysis from the etched surfaces. According to the etching time, the ZnO thin film of etched was obtained to The AES depth-profile analysis. We used to atomic force microscopy to determine the roughness of the surface. So, the root mean square of ZnO thin film was 17.02 in $Cl_2/BCl_3/Ar$ plasma. Based on these data, the ion-assisted chemical reaction was proposed as the main etch mechanism for the plasmas.

실리콘 웨이퍼 연삭가공 특성 평가에 관한 연구 (Study on Characteristics of Ground Surface in Silicon Wafer Grinding)

  • 이상직;정해도;이은상;최헌종
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 1999년도 춘계학술대회 논문집
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    • pp.128-133
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    • 1999
  • In recent years, LSI devices have become more powerful and lower-priced, caused by a development of various wafer materials and an increase in the diameter of wafers. On the other hand, these have created some serious problems in manufacturing of wafers because materials used as semiconductor substrate are very brittle. In view of this fact, there are some trials to apply shear-mode(or ductile-mode) grinding for efficient manufacturing of semiconductor wafers instead of conventional lapping process. In fact grinding process that has not only more excellent degree of accuracy but also more adaptable to fully automated manufacturing than lapping, is already used in Si machining field. This paper described the elementary studies to establish the grinding technology of wafers. First, we investigated the variation of grinding force and the transition of grinding mode as various grinding conditions. Then, it was inspected that the change of grinding force affected the integrity such as the topography and the roughness of ground surfaces, and led to the chemical defects generation and distribution in damaged layer. The degree of defects was estimated by FT-IR(Fourier Transformed Infrared) Spectroscopy and Auger Electron Spectroscopy

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