<title>Contrasts of the polarization difference projection images with linearly and circularly polarized lights</title>

Shadowing with heavy metals has been used for many years to enhance the topological features of biological macromolecular complexes. The three dimensional features present in directionaly shadowed specimens often simplifies interpretation of projection images provided by other techniques. One difficulty with the method is the relatively large amount of metal used to achieve sufficient contrast in bright field images. Thick shadow films are undesirable because they decrease resolution due to an increased tendency for microcrystalline aggregates to form, because decoration artefacts become more severe and increased cap thickness makes estimation of dimensions more uncertain.The large increase in contrast provided by the dark field mode of imaging allows the use of shadow replicas with a much lower average mass thickness. To form the images in Fig. 1, latex spheres of 0.087 μ average diameter were unidirectionally shadowed with platinum carbon (Pt-C) and a thin film of carbon was indirectly evaporated on the specimen as a support.

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Differential polarization imaging of sickled cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100102390 ◽

1988 ◽

Vol 46 ◽

pp. 62-63

Author(s):

Marcos F. Maestre

Keyword(s):

Optical Properties ◽

Theoretical Approach ◽

Polarized Light ◽

Polarization Microscopy ◽

Spectroscopic Techniques ◽

Polarization Imaging ◽

Circularly Polarized Light ◽

Circularly Polarized ◽

Microscopic Scale ◽

Chiral Structures

Recently we have developed a form of polarization microscopy that forms images using optical properties that have previously been limited to macroscopic samples. This has given us a new window into the distribution of structure on a microscopic scale. We have coined the name differential polarization microscopy to identify the images obtained that are due to certain polarization dependent effects. Differential polarization microscopy has its origins in various spectroscopic techniques that have been used to study longer range structures in solution as well as solids. The differential scattering of circularly polarized light has been shown to be dependent on the long range chiral order, both theoretically and experimentally. The same theoretical approach was used to show that images due to differential scattering of circularly polarized light will give images dependent on chiral structures. With large helices (greater than the wavelength of light) the pitch and radius of the helix could be measured directly from these images.

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Semi-automated methods for 3-D reconstruction of macromolecular complexes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100136581 ◽

1995 ◽

Vol 53 ◽

pp. 42-43

Author(s):

B. Carragher ◽

M. Whittaker

Keyword(s):

Three Dimensional ◽

Time Saving ◽

Macromolecular Complexes ◽

Symmetry Properties ◽

Dimensional Reconstruction ◽

Experienced Operator ◽

Projection Images ◽

The Individual ◽

Natural Symmetry

Techniques for three-dimensional reconstruction of macromolecular complexes from electron micrographs have been successfully used for many years. These include methods which take advantage of the natural symmetry properties of the structure (for example helical or icosahedral) as well as those that use single axis or other tilting geometries to reconstruct from a set of projection images. These techniques have traditionally relied on a very experienced operator to manually perform the often numerous and time consuming steps required to obtain the final reconstruction. While the guidance and oversight of an experienced and critical operator will always be an essential component of these techniques, recent advances in computer technology, microprocessor controlled microscopes and the availability of high quality CCD cameras have provided the means to automate many of the individual steps.During the acquisition of data automation provides benefits not only in terms of convenience and time saving but also in circumstances where manual procedures limit the quality of the final reconstruction.

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Circularly Polarized Microstrip Patch Antenna for WiMAX Applications

International Journal of Innovative Research in Computer and Communication Engineering ◽

10.15680/ijircce.2015.0308019 ◽

2015 ◽

Vol 3 (8) ◽

pp. 7265-7272

Author(s):

B.Madhuri, D r. A. Jhansi Rani,

Keyword(s):

Patch Antenna ◽

Microstrip Patch Antenna ◽

Circularly Polarized ◽

Microstrip Patch

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Sensitivity analysis of a modular circularly polarized antenna array for 60 GHz band

2020 23rd International Microwave and Radar Conference (MIKON) ◽

10.23919/mikon48703.2020.9253960 ◽

2020 ◽

Author(s):

Jan Spurek ◽

Zbynek Raida

Keyword(s):

Sensitivity Analysis ◽

Antenna Array ◽

60 Ghz ◽

Circularly Polarized

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Next Generation Laser Voltage Probing

ISTFA 2008: Conference Proceedings from the 34th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2008p0249 ◽

2008 ◽

Author(s):

Yin S Ng ◽

William Lo ◽

Kenneth Wilsher

Keyword(s):

Phase Modulation ◽

Phase Locked Loop ◽

Next Generation ◽

Solid Immersion Lens ◽

User Friendliness ◽

New Developments ◽

Polarization Difference ◽

Previous Generation ◽

Mode Locked Laser ◽

Optical Laser

Abstract We present an overview of Ruby, the latest generation of backside optical laser voltage probing (LVP) tools [1, 2]. Carrying over from the previous generation of IDS2700 systems, Ruby is capable of measuring waveforms up to 15GHz at low core voltages 0.500V and below. Several new optical capabilities are incorporated; these include a solid immersion lens (SIL) for improved imaging resolution [3] and a polarization difference probing (PDP) optical platform [4] for phase modulation detection. New developments involve Jitter Mitigation, a scheme that allows measurements of jittery signals from circuits that are internally driven by the IC’s onboard Phase Locked Loop (PLL). Additional timing features include a Hardware Phase-Locked Loop (HWPLL) scheme for improved locking of the LVP’s Mode-Locked Laser (MLL) to the tester clock as well as a clockless scheme to improve the LVP’s usefulness and user friendliness. This paper presents these new capabilities and compares these with those of the previous generation of LVP systems [5, 6].

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