<title>Implementation of phase-stepping interferometry to transmitted-light DIC microscopy for dielectric surface evaluation</title>

In a previous study, Allen video-enhanced constrast/differential interference constrast (AVEC-DIC) microscopy was used in conjunction with immunofluorescence microscopy to demonstrate that organelles and vesicle move in either direction along linear elements composed of microtubules. However, this study was limited in that the number of microtubules making up a linear element could not be determined. To overcome this limitation, we have used AVEC-DIC microscopy in conjunction with whole mount electron microscopy.Keratocytes from Rana pipiens were grown on glass coverslips as described elsewhere. Gold London Finder grids were Formvar- and carbon coated, and sterilized by exposure to ultraviolet light. It is important to select a Formvar film that gives a grey reflection when it is floated on water. A silver film is too thick and will detract from the image in the light microscope.

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Multi-mode light microscopy of microtubule assembly dynamics and chromosome movement in vivo and In vitro

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100166117 ◽

1996 ◽

Vol 54 ◽

pp. 730-731

Author(s):

E. D. Salmon ◽

J. C. Waters ◽

C. Waterman-Storer

Keyword(s):

Imaging System ◽

Ccd Camera ◽

Transmitted Light ◽

Microtubule Assembly ◽

Live Cells ◽

Optical Efficiency ◽

Multiple Band ◽

Multi Mode

We have developed a multi-mode digital imaging system which acquires images with a cooled CCD camera (Figure 1). A multiple band pass dichromatic mirror and robotically controlled filter wheels provide wavelength selection for epi-fluorescence. Shutters select illumination either by epi-fluorescence or by transmitted light for phase contrast or DIC. Many of our experiments involve investigations of spindle assembly dynamics and chromosome movements in live cells or unfixed reconstituted preparations in vitro in which photodamage and phototoxicity are major concerns. As a consequence, a major factor in the design was optical efficiency: achieving the highest image quality with the least number of illumination photons. This principle applies to both epi-fluorescence and transmitted light imaging modes. In living cells and extracts, microtubules are visualized using X-rhodamine labeled tubulin. Photoactivation of C2CF-fluorescein labeled tubulin is used to locally mark microtubules in studies of microtubule dynamics and translocation. Chromosomes are labeled with DAPI or Hoechst DNA intercalating dyes.

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Three dimensional deblurring of transmitted-light brightfield micrographs

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100148654 ◽

1993 ◽

Vol 51 ◽

pp. 564-565

Author(s):

Santosh Bhattacharyya

Keyword(s):

Image Reconstruction ◽

Three Dimensional ◽

Transmitted Light ◽

Reconstruction Algorithms ◽

3D Image Reconstruction ◽

Structural Details ◽

Spread Function ◽

Early Testing ◽

Linearized Model ◽

Image Reconstruction Algorithms

Three dimensional microscopic structures play an important role in the understanding of various biological and physiological phenomena. Structural details of neurons, such as the density, caliber and volumes of dendrites, are important in understanding physiological and pathological functioning of nervous systems. Even so, many of the widely used stains in biology and neurophysiology are absorbing stains, such as horseradish peroxidase (HRP), and yet most of the iterative, constrained 3D optical image reconstruction research has concentrated on fluorescence microscopy. It is clear that iterative, constrained 3D image reconstruction methodologies are needed for transmitted light brightfield (TLB) imaging as well. One of the difficulties in doing so, in the past, has been in determining the point spread function of the system.We have been developing several variations of iterative, constrained image reconstruction algorithms for TLB imaging. Some of our early testing with one of them was reported previously. These algorithms are based on a linearized model of TLB imaging.

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Spark Discharge over the Solid Dielectric Surface in Vacuum

Elektrichestvo ◽

10.24160/0013-5380-2018-7-31-36 ◽

2018 ◽

Vol 7 (7) ◽

pp. 31-36

Author(s):

Vyacheslav I. ASYUNIN ◽

◽

Sergei G. DAVYDOV ◽

Alexander N. DOLGOV ◽

Andrei V. KORNEYEV ◽

...

Keyword(s):

Dielectric Surface ◽

Spark Discharge ◽

Solid Dielectric

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Experimental and Simulation Investigation of the Nanoscale Charge Diffusion Process on a Dielectric Surface: Effects of Relative Humidity

The Journal of Physical Chemistry C ◽

10.1021/acs.jpcc.1c02272 ◽

2021 ◽

Author(s):

Xuejie Bai ◽

Adriaan Riet ◽

Song Xu ◽

Daniel J. Lacks ◽

Haifeng Wang

Keyword(s):

Relative Humidity ◽

Diffusion Process ◽

Surface Effects ◽

Dielectric Surface

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Current Filaments in Asymmetric Surface Dielectric Barrier Discharge

Applied Sciences ◽

10.3390/app11052079 ◽

2021 ◽

Vol 11 (5) ◽

pp. 2079

Author(s):

Cecilia Piferi ◽

Ruggero Barni ◽

H. Eduardo Roman ◽

Claudia Riccardi

Keyword(s):

Electromagnetic Waves ◽

Dielectric Surface ◽

Half Cycle ◽

Dielectric Barrier Discharges ◽

Time Duration ◽

Lower Electrode ◽

Dielectric Barrier ◽

Forward Stroke ◽

Mean Charge ◽

Mean Current

In this study, we examine the statistical properties of asymmetric surface dielectric barrier discharges (SDBD) produced by applying a periodic high voltage between two conducting displaced electrodes, located at the opposite sides of a flat dielectric panel. Here, the asymmetry refers to the fact that the lower electrode is fully covered with an insulating material, while the upper one, glued onto the dielectric surface, is otherwise left exposed to the air. Such a configuration allows the formation of a thin layer of plasma above the insulating surface. A single cycle signal consists of two well-separated half-cycle patterns, denoted as forward and backward strokes, corresponding to positive and negative voltages, respectively. They display a quite complex discharge pattern constituted by a sequence of individual peaks (bursts) of varying current and time duration. Specifically, we find that backward stroke bursts carry a positive mean charge Q≃0.3 nC and mean current I≃35 mA, with a mean duration τ≃15 ns, while forward stroke bursts have a negative mean charge Q≃−0.1 nC, a mean current I≃−20 mA, and a mean duration τ≃11 ns. The statistical analysis suggests that power injection can be tailored to produce the active agents in the plasma needed for a particular application. We also determined discharge spatial correlation patterns from measurements of the associated stimulated optical emission. The optical excitations occur as a result of the ionizing effect of the electromagnetic waves which ignite the discharge, followed by the electric current flow. In particular, we point out that one of the phases of the discharge is compatible with a cathode directed streamer phenomenon (backward stroke), while the mechanism acting for a forward stroke has a different structure.

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Transmitted Light Photography Of Watermarks

ICCM Bulletin ◽

10.1179/iccm.1981.7.1.007 ◽

1981 ◽

Vol 7 (1) ◽

pp. 50-51

Author(s):

Harry McCarthy ◽

Lydia Preiss

Keyword(s):

Transmitted Light

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