Intersection point method ( IPM ): theoretical basis and application to spectrophotometric analyses

Various methods of video-enhanced microscopy combine TV cameras with light microscopes creating images with improved resolution, contrast and visibility of fine detail, which can be recorded rapidly and relatively inexpensively. The AVEC (Allen Video-enhanced Contrast) method avoids polarizing rectifiers, since the microscope is operated at retardations of λ/9- λ/4, where no anomaly is seen in the Airy diffraction pattern. The iris diaphram is opened fully to match the numerical aperture of the condenser to that of the objective. Under these conditions, no image can be realized either by eye or photographically. Yet the image becomes visible using the Hamamatsu C-1000-01 binary camera, if the camera control unit is equipped with variable gain control and an offset knob (which sets a clamp voltage of a D.C. restoration circuit). The theoretical basis for these improvements has been described.

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Scanning Electron Microscopy of Dried and Acid Treated Shells of Difflugia

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010007268x ◽

1973 ◽

Vol 31 ◽

pp. 448-449

Author(s):

Barry S. Eckert ◽

S. M. McGee-Russell

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Critical Point ◽

Point Method ◽

External Structure ◽

Cell Locomotion ◽

Single Opening ◽

Scanning Electron

Difflugia lobostoma is a shelled amoeba. The shell is an external structure of considerable mass which presents the animal with special restrictions in cell locomotion which are met by the development of active pseudopodial lobopodia containing, apparently, an organized system of thick and thin microfilaments (Eckert and McGee-Russell, 1972). The shell is constructed of sand grains picked up from the environment, and cemented into place with a secretion. There is a single opening through which lobopods extend. The organization of the shell was studied by scanning electron microscopy (SEM).Intact shells or animals with shells were dried by the critical point method of Anderson (1966) or air dried, after primary fixation in glutaraldehyde.

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Microdiffraction analysis of precipitate crystallography and morphology in Al alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100177908 ◽

1990 ◽

Vol 48 (4) ◽

pp. 954-955

Author(s):

B.C. Muddle ◽

G.R. Hugo

Keyword(s):

Point Group ◽

Hexagonal Lattice ◽

Intersection Point ◽

Saed Pattern ◽

Point Symmetry ◽

Hexagonal Symmetry ◽

Precipitate Crystal ◽

The Matrix ◽

The Subject ◽

Electron Microdiffraction

Electron microdiffraction has been used to determine the crystallography of precipitation in Al-Cu-Mg-Ag and Al-Ge alloys for individual precipitates with dimensions down to 10 nm. The crystallography has been related to the morphology of the precipitates using an analysis based on the intersection point symmetry. This analysis requires that the precipitate form be consistent with the intersection point group, defined as those point symmetry elements common to precipitate and matrix crystals when the precipitate crystal is in its observed orientation relationship with the matrix.In Al-Cu-Mg-Ag alloys with high Cu:Mg ratios and containing trace amounts of silver, a phase designated Ω readily precipitates as thin, hexagonal-shaped plates on matrix {111}α planes. Examples of these precipitates are shown in Fig. 1. The structure of this phase has been the subject of some controversy. An SAED pattern, Fig. 2, recorded from matrix and precipitates parallel to a <11l>α axis is suggestive of hexagonal symmetry and a hexagonal lattice has been proposed on the basis of such patterns.

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Severe Paradoxical Dysphonia in Two Young Women

American Journal of Speech-Language Pathology ◽

10.1044/1058-0360.0203.52 ◽

1993 ◽

Vol 2 (3) ◽

pp. 52-55 ◽

Cited By ~ 1

Author(s):

Michael Collins ◽

Robert McDonald ◽

Robert Stanley ◽

Timothy Donovan ◽

C. Frank Bonebrake

Keyword(s):

Young Women ◽

Theoretical Basis ◽

Therapeutic Regimen ◽

Instrumental Data ◽

Relationship Of ◽

The Relationship

This report describes an unusual and persistent dysphonia in two young women who had taken a therapeutic regimen of isotretinoin for intractable acne. We report perceptual and instrumental data for their dysphonia, and pose a theoretical basis for the relationship of dysphonia to this drug. We also provide recommendations for reducing the risk of acquiring a dysphonia during the course of treatment with isotretinoin.

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Translation Research for the Rehabilitation of Left Spatial Neglect and Associated Disorders of Attention in Stroke Patients

Perspectives on Neurophysiology and Neurogenic Speech and Language Disorders ◽

10.1044/nnsld18.2.55 ◽

2008 ◽

Vol 18 (2) ◽

pp. 55-65 ◽

Cited By ~ 2

Author(s):

Nkiruka Arene ◽

Argye E. Hillis

Keyword(s):

Theoretical Basis ◽

Attention Bias ◽

Spatial Neglect ◽

Clinical Use ◽

Stroke Patients ◽

Translation Research ◽

Unilateral Neglect ◽

Assessment And Treatment ◽

Sound Theoretical Basis ◽

Review Current

Abstract The syndrome of unilateral neglect, typified by a lateralized attention bias and neglect of contralateral space, is an important cause of morbidity and disability after a stroke. In this review, we discuss the challenges that face researchers attempting to elucidate the mechanisms and effectiveness of rehabilitation treatments. The neglect syndrome is a heterogeneous disorder, and it is not clear which of its symptoms cause ongoing disability. We review current methods of neglect assessment and propose logical approaches to selecting treatments, while acknowledging that further study is still needed before some of these approaches can be translated into routine clinical use. We conclude with systems-level suggestions for hypothesis development that would hopefully form a sound theoretical basis for future approaches to the assessment and treatment of neglect.

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