Interface Nerve Tissue-Silicon Nanowire for Regeneration of Injured Nerve and Creation of Bio-Electronic Device

Ultrastructural changes in sciatic nerve tissue: Effects of passive maternal smoking

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100076858 ◽

1983 ◽

Vol 41 ◽

pp. 650-651

Author(s):

Amankwah K.S. ◽

A.D. Weberg ◽

R.C. Kaufmann

Keyword(s):

Sciatic Nerve ◽

Maternal Smoking ◽

Ultrastructural Level ◽

Uranyl Acetate ◽

Nerve Tissue ◽

Ultrastructural Changes ◽

Cacodylate Buffer ◽

And Control ◽

Spontaneous Delivery

Previous research has revealed that passive (involuntary inhalation) tobacco smoking during gestation can have adverse effects upon the developing fetus. These prior investigations did not concentrate on changes in fetal morphology. This study was undertaken to delineate fetal neural abnormalities at the ultrastructural level in mice pups exposed in utero to passive maternal smoking.Pregnant study animals, housed in a special chamber, were subjected to cigarette smoke daily from conception until delivery. Blood tests for determination of carbon monoxide levels were run at 15-18 days gestation. Sciatic nerve tissue from experimental and control animals were obtained following spontaneous delivery and fixed in 2.5% gluteraldehyde in 0.1M cacodylate buffer pH 7.3. The samples were post-fixed in osmium ferrocyanide (1:1 mixture of 1.5% aqueous OSO4 and 2.5% K4 Fe(CN)6). Following dehydration, the tissues were infiltrated with and embedded in Spurr. Sections were stained with uranyl acetate and lead citrate.

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Electronic Cone Illumination with the Conventional Transmission Electron Microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100077980 ◽

1977 ◽

Vol 35 ◽

pp. 72-73

Author(s):

William Krakow

Keyword(s):

Electronic Device ◽

Chromatic Aberration ◽

Objective Lens ◽

Hollow Cone ◽

Transmission Electron ◽

Lissajous Figures ◽

High Resolution Images ◽

Imaging Mode ◽

Diffraction Patterns ◽

Transmission Microscope

An electronic device has been constructed which manipulates the primary beam in the conventional transmission microscope to illuminate a specimen under a variety of virtual condenser aperture conditions. The device uses the existing tilt coils of the microscope, and modulates the D.C. signals to both x and y tilt directions simultaneously with various waveforms to produce Lissajous figures in the back-focal plane of the objective lens. Electron diffraction patterns can be recorded which reflect the manner in which the direct beam is tilted during exposure of a micrograph. The device has been utilized mainly for the hollow cone imaging mode where the device provides a microscope transfer function without zeros in all spatial directions and has produced high resolution images which are also free from the effect of chromatic aberration. A standard second condenser aperture is employed and the width of the cone annulus is readily controlled by defocusing the second condenser lens.

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Resistance Monitor and Control for Vacuum Evaporation of Metals and Carbon

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100092827 ◽

1976 ◽

Vol 34 ◽

pp. 572-573

Author(s):

Russell L. Steere ◽

Eric F. Erbe ◽

J. Michael Moseley

Keyword(s):

Electronic Device ◽

Point Sources ◽

High Contrast ◽

Variable Resistor ◽

Quality Of Results ◽

Low Contrast ◽

Evaporation Source ◽

And Control ◽

At Will

We have designed and built an electronic device which compares the resistance of a defined area of vacuum evaporated material with a variable resistor. When the two resistances are matched, the device automatically disconnects the primary side of the substrate transformer and stops further evaporation.This approach to controlled evaporation in conjunction with the modified guns and evaporation source permits reliably reproducible multiple Pt shadow films from a single Pt wrapped carbon point source. The reproducibility from consecutive C point sources is also reliable. Furthermore, the device we have developed permits us to select a predetermined resistance so that low contrast high-resolution shadows, heavy high contrast shadows, or any grade in between can be selected at will. The reproducibility and quality of results are demonstrated in Figures 1-4 which represent evaporations at various settings of the variable resistor.

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Digital image processing methods applied to the study of annealing time on semiconductor-metal eutectic composites

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100106302 ◽

1988 ◽

Vol 46 ◽

pp. 848-849

Author(s):

J. Hefter

Keyword(s):

Image Processing ◽

Digital Image Processing ◽

Digital Image ◽

Electronic Device ◽

Processing System ◽

Average Diameter ◽

Eutectic Solidification ◽

Metal Silicide ◽

The Matrix ◽

Microscopic Studies

Semiconductor-metal composites, formed by the eutectic solidification of silicon and a metal silicide have been under investigation for some time for a number of electronic device applications. This composite system is comprised of a silicon matrix containing extended metal-silicide rod-shaped structures aligned in parallel throughout the material. The average diameter of such a rod in a typical system is about 1 μm. Thus, characterization of the rod morphology by electron microscope methods is necessitated.The types of morphometric information that may be obtained from such microscopic studies coupled with image processing are (i) the area fraction of rods in the matrix, (ii) the average rod diameter, (iii) an average circularity (roundness), and (iv) the number density (Nd;rods/cm2). To acquire electron images of these materials, a digital image processing system (Tracor Northern 5500/5600) attached to a JEOL JXA-840 analytical SEM has been used.

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In situ TEM measurements of the electrical properties of interface dislocations

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100131322 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1338-1339

Author(s):

F. M. Ross ◽

R. Hull ◽

D. Bahnck ◽

J. C. Bean ◽

L. J. Peticolas ◽

...

Keyword(s):

Electrical Properties ◽

Electronic Device ◽

In Situ Tem ◽

Device Performance ◽

Misfit Dislocations ◽

Electrical Characteristics ◽

Strained Layer ◽

Transmission Electron ◽

Interfacial Dislocations

We describe an investigation of the electrical properties of interfacial dislocations in strained layer heterostructures. We have been measuring both the structural and electrical characteristics of strained layer p-n junction diodes simultaneously in a transmission electron microscope, enabling us to correlate changes in the electrical characteristics of a device with the formation of dislocations.The presence of dislocations within an electronic device is known to degrade the device performance. This degradation is of increasing significance in the design and processing of novel strained layer devices which may require layer thicknesses above the critical thickness (hc), where it is energetically favourable for the layers to relax by the formation of misfit dislocations at the strained interfaces. In order to quantify how device performance is affected when relaxation occurs we have therefore been investigating the electrical properties of dislocations at the p-n junction in Si/GeSi diodes.

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Immunocytochemical methodology for the localization of neuronal antigens at the ultrastructural level

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100161941 ◽

1990 ◽

Vol 48 (3) ◽

pp. 876-877

Author(s):

Jorge Pecci Saavedra ◽

Mark Connaughton ◽

Juan José López ◽

Alicia Brusco

Keyword(s):

Spinal Cord ◽

Substantia Nigra ◽

Polyclonal Antibodies ◽

Ultrastructural Level ◽

Point Of View ◽

Nerve Tissue ◽

Tissue Fixation ◽

Optimal Conditions ◽

Interpeduncular Nucleus ◽

Technical Point

The use of antibodies as labels for the localization of specific molecules in the nervous systan has been extensively applied in recent years. Both monoand polyclonal antibodies or antisera have been employed. The knowledge of the organization of neuronal connectivities, gliovascular relationships, glioneuronal relationships and other features of nerve tissue has greatly increased.A number of areas of the nervous systan have been analyzed in our laboratory, including the nuclei of the raphe system, the reticular formation, interpeduncular nucleus, substantia nigra, caudate nucleus, putamen, pallidum, spinal cord, pineal gland and others.From a technical point of view, a number of variables needed to be taken into account in order to obtain reliable and reproducible results. The design of the optimal conditions of tissue fixation, embedding, sectioning, dilution of antibodies, and adaptation of Sternberger PAP technique were sane of the parameters taken into account to optimize the results. It is critical that each step of the technique be defined for each particular case.

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