Determination of velocity distribution, angular distribution, and vector correlation of photofragments using sub-Doppler fluorescence-imaging method

In studying ion implanted semiconductors and fast neutron irradiated metals, the need for characterizing small dislocation loops having diameters of a few hundred angstrom units usually arises. The weak beam imaging method is a powerful technique for analyzing these loops. Because of the large reduction in stacking fault (SF) fringe spacing at large sg, this method allows for a rapid determination of whether the loop is faulted, and, hence, whether it is a perfect or a Frank partial loop. This method was first used by Bicknell to image small faulted loops in boron implanted silicon. He explained the fringe spacing by kinematical theory, i.e., ≃l/(Sg) in the fault fringe in depth oscillation. The fault image contrast formation mechanism is, however, really more complicated.

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Multiplexed Plasmonic Nano-Labeling for Bioimaging of Cytological Stained Samples

Cancers ◽

10.3390/cancers13143509 ◽

2021 ◽

Vol 13 (14) ◽

pp. 3509

Author(s):

Paule Marcoux-Valiquette ◽

Cécile Darviot ◽

Lu Wang ◽

Andrée-Anne Grosset ◽

Morteza Hasanzadeh Kafshgari ◽

...

Keyword(s):

Accurate Determination ◽

Cell Types ◽

Fine Needle Biopsy ◽

Dark Field ◽

Imaging Method ◽

New Methods ◽

Formalin Fixed Paraffin ◽

Dark Field Microscopy ◽

Formalin Fixed Paraffin Embedded

Reliable cytopathological diagnosis requires new methods and approaches for the rapid and accurate determination of all cell types. This is especially important when the number of cells is limited, such as in the cytological samples of fine-needle biopsy. Immunoplasmonic-multiplexed- labeling may be one of the emerging solutions to such problems. However, to be accepted and used by the practicing pathologists, new methods must be compatible and complementary with existing cytopathology approaches where counterstaining is central to the correct interpretation of immunolabeling. In addition, the optical detection and imaging setup for immunoplasmonic-multiplexed-labeling must be implemented on the same cytopathological microscope, not interfere with standard H&E imaging, and operate as a second easy-to-use imaging method. In this article, we present multiplex imaging of four types of nanoplasmonic markers on two types of H&E-stained cytological specimens (formalin-fixed paraffin embedded and non-embedded adherent cancer cells) using a specially designed adapter for SI dark-field microscopy. The obtained results confirm the effectiveness of the proposed optical method for quantitative and multiplex identification of various plasmonic NPs, and the possibility of using immunoplasmonic-multiplexed-labeling for cytopathological diagnostics.

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Photoelectron Angular Distribution of Thin Films of Copper Phthalocyanine on MoS2 Surfaces: Quantitative Determination of Molecular Orientation

Molecular Crystals and Liquid Crystals Science and Technology Section A Molecular Crystals and Liquid Crystals ◽

10.1080/10587259508033996 ◽

1995 ◽

Vol 267 (1) ◽

pp. 211-216 ◽

Cited By ~ 12

Author(s):

Koji Kamiya ◽

Masahiro Momose ◽

Yoshiya Harada ◽

Nobuo Ueno ◽

Takafumi Miyazaki ◽

...

Keyword(s):

Thin Films ◽

Angular Distribution ◽

Quantitative Determination ◽

Molecular Orientation ◽

Copper Phthalocyanine ◽

Photoelectron Angular Distribution

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Feasibility of Extracting Velocity Distribution in Choriocapillaris in Human Eyes from ICG Dye Angiograms

Journal of Biomechanical Engineering ◽

10.1115/1.2165692 ◽

2005 ◽

Vol 128 (2) ◽

pp. 203-209 ◽

Cited By ~ 10

Author(s):

L. Zhu ◽

Y. Zheng ◽

C. H. von Kerczek ◽

L. D. T. Topoleski ◽

R. W. Flower

Keyword(s):

Velocity Distribution ◽

Fluorescence Intensity ◽

Conversion Factor ◽

Blood Velocity ◽

New Approach ◽

Pixel Location ◽

Choroidal Vasculature ◽

Dye Fluorescence ◽

Human Eyes

Indocyanine green (ICG) dye angiography has been used by ophthalmologists for routine examination of the choroidal vasculature in human eyes for more than 20years. In this study, a new approach is developed to extract information from ICG dye angiograms about blood velocity distribution in the choriocapillaris and its feeding blood vessels. ICG dye fluorescence intensity rise and decay curves are constructed for each pixel location in each image of the choriocapillaris in an ICG angiogram. It is shown that at each instant of time the magnitude of the local instantaneous dye velocity in the choriocapillaris is proportional to both the slope of the ICG dye fluorescence intensity curve and the dye concentration. This approach leads to determination of the absolute value of blood velocity in the choriocapillaris, assuming an appropriate scaling, or conversion factor can be determined. It also enables comparison of velocities in different regions of the choriocapillaris, since the conversion factor is independent of the vessel location. The computer algorithm developed in this study can be used in clinical applications for diagnostic purposes and for assessment of the efficacy of laser therapy in human eyes.

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Measurement and analysis of species distribution in laser-induced ablation plasma of an aluminum-magnesium alloy

Plasma Science and Technology ◽

10.1088/2058-6272/ac401a ◽

2021 ◽

Author(s):

Junxiao Wang ◽

Shuqing Wang ◽

Lei Zhang ◽

Maogen Su ◽

Duixiong Sun ◽

...

Keyword(s):

Species Distribution ◽

Laser Energy ◽

Integral Intensity ◽

Spectral Lines ◽

Imaging Method ◽

Measurement And Analysis ◽

Ablation Plasma ◽

Spatio Temporal ◽

Differential Imaging

Abstract We proposed a theoretical spatio-temporal imaging method, which was based on the thermal model of laser ablation and the two-dimensional axisymmetric multi-species hydrodynamics model. By using the intensity formula, the integral intensity of spectral lines could be calculated and the corresponding images of intensity distribution could be drawn. Through further image processing such as normalization, determination of minimum intensity, combination and color filtering, a relatively clear species distribution image in the plasma could be obtained. Using the above method, we simulated the plasma ablated from Al-Mg alloy by different laser energies under 1 atm argon, and obtained the theoretical spatio-temporal distributions of Mg I, Mg II, Al I, Al II and Ar I species, which are almost consistent with the experimental results by differential imaging. Compared with the experimental decay time constants, the consistency is higher at low laser energy, indicating that our theoretical model is more suitable for the plasma dominated by laser-supported combustion wave.

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