Exploring the direction of dislocation line in pyramid section of KDP crystal using 3D confocal microscope

1978 ◽

Vol 36 (1) ◽

pp. 570-571

Author(s):

F. Louchet ◽

L.P. Kubin

Keyword(s):

Strain Rate ◽

Radiation Effects ◽

Dislocation Line ◽

Critical Length ◽

Local Strain ◽

Local Flow ◽

Double Kink ◽

Dislocation Densities ◽

Frictional Forces ◽

Local Strain Rate

Investigation of frictional forces -Experimental techniques and working conditions in the high voltage electron microscope have already been described (1). Care has been taken in order to minimize both surface and radiation effects under deformation conditions.Dislocation densities and velocities are measured on the records of the deformation. It can be noticed that mobile dislocation densities can be far below the total dislocation density in the operative system. The local strain-rate can be deduced from these measurements. The local flow stresses are deduced from the curvature radii of the dislocations when the local strain-rate reaches the values of ∿ 10-4 s-1.For a straight screw segment of length L moving by double-kink nucleation between two pinning points, the velocity is :where ΔG(τ) is the activation energy and lc the critical length for double-kink nucleation. The term L/lc takes into account the number of simultaneous attempts for double-kink nucleation on the dislocation line.

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The influence of confocal microscope design on imaging performance

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100146564 ◽

1993 ◽

Vol 51 ◽

pp. 144-145

Author(s):

C J R Sheppard

Keyword(s):

Image Quality ◽

Fluorescence Imaging ◽

Confocal Microscope ◽

Industrial Applications ◽

Three Dimensions ◽

Design Parameters ◽

Weak Signals ◽

Size And Shape ◽

Imaging Performance ◽

Fundamental Limitation

The confocal microscope is now widely used in both biomedical and industrial applications for imaging, in three dimensions, objects with appreciable depth. There are now a range of different microscopes on the market, which have adopted a variety of different designs. The aim of this paper is to explore the effects on imaging performance of design parameters including the method of scanning, the type of detector, and the size and shape of the confocal aperture.It is becoming apparent that there is no such thing as an ideal confocal microscope: all systems have limitations and the best compromise depends on what the microscope is used for and how it is used. The most important compromise at present is between image quality and speed of scanning, which is particularly apparent when imaging with very weak signals. If great speed is not of importance, then the fundamental limitation for fluorescence imaging is the detection of sufficient numbers of photons before the fluorochrome bleaches.

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A new miniaturized confocal microscope allows immediate in vivo histology of different organs

Zeitschrift für Gastroenterologie ◽

10.1055/s-2005-920245 ◽

2005 ◽

Vol 43 (05) ◽

Author(s):

M Goetz ◽

MF Neurath ◽

P Delaney ◽

S Gregor ◽

D Strand ◽

...

Keyword(s):

Confocal Microscope

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A white light confocal microscope for spectrally resolved multidimensional imaging

Journal of Microscopy ◽

10.1111/j.1365-2818.2007.01803.x ◽

2007 ◽

Vol 227 (3) ◽

pp. 203-215 ◽

Cited By ~ 60

Author(s):

J. H. FRANK ◽

A. D. ELDER ◽

J. SWARTLING ◽

A. R. VENKITARAMAN ◽

A. D. JEYASEKHARAN ◽

...

Keyword(s):

White Light ◽

Confocal Microscope ◽

Multidimensional Imaging ◽

Spectrally Resolved

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Cylindrically Anisotropic Tubes Containing a Line Dislocation

Volume 3: Design and Analysis ◽

10.1115/pvp2006-icpvt-11-93188 ◽

2006 ◽

Author(s):

Chung-Hao Wang

Keyword(s):

State Space ◽

Dislocation Line ◽

Longitudinal Axis ◽

The State ◽

Fourier Series Expansion ◽

General Solutions ◽

Mixed Dislocation ◽

Line Dislocation ◽

Space Formulation ◽

Cylindrically Anisotropic

An analytical solution of the problem of a cylindrically anisotropic tube which contains a line dislocation is presented in this study. The state space formulation in conjunction with the eigenstrain theory is proved to be a feasible and systematic methodology to analyze a tube with the existence of dislocations. The state space formulation which expediently groups the displacements and the cylindrical surface traction can construct a governing differential matrix equation. By using Fourier series expansion and the well developed theory of matrix algebra, the asymmetrical solutions are not only explicit but also compact in form. The dislocation considered in this study is a kind of mixed dislocation which is the combination of edge dislocations and a screw dislocation and the dislocation line is parallel to the longitudinal axis of the tube. The degeneracy of the eigen relation and the technique to determine the inverse of a singular matrix are thoroughly discussed, so that the general solutions can be applied to the case of isotropic tubes, which is one of the novel features of this research. The results of isotropic problems, which are belong to the general solutions, are compared with the well-established expressions in the literature. The satisfied correspondences of these comparisons indicate the validness of this study. A cylindrically orthotropic tube is also investigated as an example and the numerical results for the displacements and tangential stress on the outer surface are displayed. The effects on surface stresses due to the existence of a dislocation appear to have a characteristic of localized phenomenon.

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Bifunctional iRGD-anti-CD3 enhances antitumor potency of T cells by facilitating tumor infiltration and T-cell activation

Journal for ImmunoTherapy of Cancer ◽

10.1136/jitc-2020-001925 ◽

2021 ◽

Vol 9 (5) ◽

pp. e001925

Author(s):

Shujuan Zhou ◽

Fanyan Meng ◽

Shiyao Du ◽

Hanqing Qian ◽

Naiqing Ding ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

T Cell Activation ◽

Cell Activation ◽

Confocal Microscope ◽

Mechanistic Studies ◽

Tumor Spheroids ◽

Antitumor Effects ◽

Transport Pathway

BackgroundPoor infiltration and limited activation of transferred T cells are fundamental factors impeding the development of adoptive cell immunotherapy in solid tumors. A tumor-penetrating peptide iRGD has been widely used to deliver drugs deep into tumor tissues. CD3-targeting bispecific antibodies represent a promising immunotherapy which recruits and activates T cells.MethodsT-cell penetration was demonstrated in tumor spheroids using confocal microscope, and in xenografted tumors by histology and in vivo real-time fluorescence imaging. Activation and cytotoxicity of T cells were assessed by flow cytometry and confocal microscope. Bioluminescence imaging was used to evaluate in vivo antitumor effects, and transmission electron microscopy was used for mechanistic studies.ResultsWe generated a novel bifunctional agent iRGD-anti-CD3 which could immobilize iRGD on the surface of T cells through CD3 engaging. We found that iRGD-anti-CD3 modification not only facilitated T-cell infiltration in 3D tumor spheroids and xenografted tumor nodules but also induced T-cell activation and cytotoxicity against target cancer cells. T cells modified with iRGD-anti-CD3 significantly inhibited tumor growth and prolonged survival in several xenograft mouse models, which was further enhanced by the combination of programmed cell death protein 1 (PD-1) blockade. Mechanistic studies revealed that iRGD-anti-CD3 initiated a transport pathway called vesiculovacuolar organelles in the endothelial cytoplasm to promote T-cell extravasation.ConclusionAltogether, we show that iRGD-anti-CD3 modification is an innovative and bifunctional strategy to overcome major bottlenecks in adoptive cell therapy. Moreover, we demonstrate that combination with PD-1 blockade can further improve antitumor efficacy of iRGD-anti-CD3-modified T cells.

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