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An Electrophoretic Analysis Of The Genetic Relationship Between Etheostoma Nigrum And Etheostoma Olmstedi (Percidae: Etheostomatini) In The James River Drainage Of Virginia, John Stuart Prince Jr.

Master's Theses

Etheostoma nigrum Rafinesque 1820, the Johnny darter ranges from Alabama to the Hudson Bay and from Colorado east to the Atlantic slope in the James, Roanoke, Tar and Neuse Rivers. Etheostoma olmstedi Storer 1842, the tesselated darter, is restricted to the east coast in the Atlantic and Lake Ontario drainage. In the James and Roanoke River systems in Virginia E. nigrum occupies the piedmont and montane regions whereas E. olmstedi primarily inhabits the coastal plain. The relationship between the morphologically similar species of darters (subgenus Boleosoma) is controversial and has been investigated by several authors. Stone (1947), using multiple character …

Anatomy And Systematics Of Penthorum L., Melanie Lynn Haskins

Master's Theses

The genus Penthorum L. consists of two species of perennial herbs, P. sedoides of eastern North America and P. chinense of eastern Asia. Penthorum has long be.en considered intermediate between crassulaceae and Saxifragaceae. An anatomical study of both species was undertaken to contribute to a better understanding of the relationships of these plants. Prominent anatomical features of Penthorum include: an aerenchymatous cortex and closely-spaced collateral vascular bundles of stems; one-trace unilacunar nodes; brochidodromous venation, rosoid teeth bearing hydathodes, and anomocytic stomata of leaves; angular vessel elements with many-barred scalariform perforation plates and alternate to scattered intervascular pits; thin-walled non-septate fiber-tracheids; …

Atp Defendent Na+ Transport And The Characterization Of Na+ / Nh4+ Exchange In Basolateral Vesicles Of The Blue Crab, Callinectes Sapidus, Gill, Linda Ann Fuhrman

Master's Theses

ATP dependent Na⁺ transport was denonstrated in purified ba.solateral vesicles of the blue crab (Callinectes sapidus) gill. Active Na⁺ uptake was dependent upon the intravesicular presence of either K⁺ or NH; as a counterion. Final membrane preparations consist of inside-out basolateral vesicles, evidenced by intravesicular ouabain (1 rrM) and extravesicular vanadate (1 rnM) ²²Na ⁺ uptake inhibition. Na⁺/NH₄⁺exchange rates were investigated by detennining the NH; concentration in the recovered extravesicular nedium and by using the kinetic capabilities of a DU7 spectrophotareter. These purified basolateral membranes, rich in Na⁺,K^{+ …}

The Trend In Canopy Composition In A Young Mesic Forest, Zhenchang Li

Masters Theses

Brewer Woods, a young disturbed mesic sugar maple-beech (Acer saccharum-Fagus grandifolia) forest in Kalamazoo Co., Michigan, was investigated by point-quarter and transition matrix methods. The results indicate that this forest is dominated by sugar maple in both canopy and understory composition. Beech is the second most important species. Fourteen species were found as canopy trees or replacements. The hypothesis that a young forest is more diverse than comparable climax forests such as Warren Woods and Hueston Woods was supported. Its successional trend is that sugar maple will become more abundant at the expense of the other species. Beech is a …

The Effects Of Stress On The Blood Calcium Level In The Male White Rat (Rattus Norvegicus), Howard Perry Cobb

Master's Theses

THE EFFECTS OF STRESS ON THE BLOOD CALCIUM LEVEL IN THE MALE WHITE RAT (Rattus norvegicus) by Howard Perry Cobb I I I was writ ten as part of the requirements for a Master of Science degree in Biology at the University of Richmond (May, 1985). The present experiment was designed to determine whether parathyroid hormone (PTH) can be considered a "stress" hormone. Parathyroidectomized (PX) male rats (160-200 g) were injected with 10, 20, or 30 USP units of PTH per 100 g body weight and subjected to confinement/UHF stress for a 1.5-h period. Serum calcium levels of these PX …

Quantitation Of Scanning Electron Microscopic Urinary Cytology, M. Cano, R. B. Wilson, S. M. Cohen

Scanning Electron Microscopy

Using scanning electron microscopy (SEM), differences in cell surface morphology are identifiable between normal urothelium and malignant urothelia including the presence of pleomorphic microvilli (PMV). PMV have been reported in carcinomas of the urinary bladder, and they appear early in the pathogenesis of these tumors in animal models. Preliminary studies in our laboratory and others' demonstrated similar changes in tissue and cytologic specimens from patients with bladder cancer. We observed and evaluated normal and neoplastic cells of the human bladder by SEM in a preliminary assessment of surface topography with regard to tumor growth, grade, and stage. However, while these …

Simulation With Pharmacological Agents Of Radiation Damage To Small Intestinal Villi, M. Indran, F. C. Boyle, K. E. Carr

Scanning Electron Microscopy

Irradiation induces damage to intestinal villi, resulting in a progressive decline in villous height and changes in topography. Gamma and neutron radiation are reported to cause changes in the structure of smooth muscle and nerve twigs of the intestinal wall. It is possible, therefore, that villous collapse may be due partly to changes in the underlying stromal elements as a result of damage to nerve or muscle.

To test this hypothesis, mice were treated with the drug reserpine which is known to affect the neural control of intestinal smooth muscle function and the small intestine was examined for topographical and …

Stroboscopic Technique For Dynamic Observation Of Ferromagnetic Domains At Low Frequencies In Scanning Electron Microscopy, T. Ikuta

Scanning Electron Microscopy

A new stroboscopic technique for the observation of periodic phenomena at low frequencies (10 -100 Hz) in scanning electron microscopy (SEM) is developed in the present study. This new technique is based on the line-sampling stroboscopy instead of the point-sampling stroboscopy which has been commonly used for the dynamic observation at high frequencies (> 1 kHz). In this stroboscopy, a multi-frame display with the individual stroboscopic image at different phase can be easily introduced with no reduction of the detection efficiency.

The main application of the present stroboscopy at low frequencies is the dynamic observation of magnetic domains. In this …

A Dynamic Single E-Beam Short/Open Testing Technique, M. Brunner, B. Lischke

Scanning Electron Microscopy

Several electron beam techniques for electrical testing of interconnection modules have been presented by different authors in recent years. Most techniques use two or more electron beam energies to establish a charging and a non-loading reading mode. The present paper discusses the feasibility of employing the same beam energy for charging contact pads and reading pad potentials. This avoids the necessity of high voltage switching as used for altering the beam energy. A switching time of 100 us between 2 kV and 4 kV beam voltage which is restricted to this range has been reported earlier. Without switching, higher beam …

Interactions Between Spermatozoa And The Crypts, Cilia, And Mucus Of The Cervix In The Ewe, William P. Wergin

Scanning Electron Microscopy

In ruminants, minor cervical folds, commonly called crypts, temporarily store spermatozoa for a short interval of time between insemination and fertilization. However, the mechanism by which spermatozoa are transported to these crypts and subsequently to the uterus is not known. To study this problem, cervical tissue, which was removed from ewes that were naturally inseminated by rams at estrus, was examined with the scanning electron microscope to determine the physical associations that occur between the spermatozoa and the structural features of the cervix. The study indicates that the spermatozoa generally are not oriented parallel to the longitudinal axis of the …

The Effect Of High Energy (Hze) Particle Radiation (40ar) On Aging Parameters Of Mouse Hippocampus And Retina, D. E. Philpott, W. Sapp, J. Miquel, K. Kato, R. Corbett, J. Stevenson, S. Black, K. A. Lindseth, E. V. Benton

Scanning Electron Microscopy

Eight month old C57BL6 mice were exposed (head only) to 0.5 rad or 50 rads of Argon particles at the Lawrence Berkeley Radiation Facility, CA. Neuromotor performance was assessed monthly for six months beginning twelve weeks post-irradiation using a ''string test". The decline in motor performance was dose-related and none of the animals was able to complete the task after four months of testing. Morphological changes were monitored six and twelve months post-irradiation by light and electron microscopy. The synaptic density in the CA-1 area of the hippocampus decreased six and twelve months after irradiation. The decrease after twelve months …

Two Quantum Photoemission In Semiconductors, J. M. Moison, M. Bensoussan

Scanning Electron Microscopy

Two-quantum photoemission is a process in which two times the photon energy is transferred to the photoelectron. In this process, the photoelectron observed in the vacuum keeps a "memory" of the intermediate empty state by which it transited after its first excitation, and before its second excitation and its final escape. We discuss here the experimental problems involved and the information obtained in the case of the semiconductors Si and InP. We show that ballistic or non-ballistic electrons can be selected by an adequate choice of experimental conditions, yielding information on both the static and dynamic properties of the empty …

The Electron Microscope Detection And X-Ray Quantitation Of Cations In Bacterial Cells, D. C. Sigee, M. H. El-Masry, R. H. Al-Rabaee

Scanning Electron Microscopy

Electron microscope autoradiography and X-ray microanalysis have been used for the detection and quantitation of cations in the bacterium Pseudomonas tabaci. These techniques differ in the information they provide (relating to either cation uptake or in situ levels), their applicability to different cations, their sensitivity and their spatial resolution. With uptake of ⁶³Ni²⁺, high resolution autoradiography (involving gold latensification and physical development) demonstrated a high degree of cation localisation to the central nucleoid area (glutaraldehyde-fixed cells) and within this to the constituent chromatin (acetic-alcohol preparations).

X-ray microanalysis of whole bacterial cells revealed the presence of substantial levels …

The Influence Of Epidermal Growth Factor On Surface Morphology Of Fetal Rat Hepatocytes In Primary Culture, Ira H. Ames, Robert A. Richman, Gerald B. Gordon, Barbara A. Toly, Mark R. Benedict, Maureen A. Barcza

Scanning Electron Microscopy

In an attempt to understand the hormonal regulation of somatomedin secretion in the fetus, we have confirmed that epidermal growth factor (EGF) stimulates fetal rat hepatocytes in primary culture to secrete somatomedin in a time and a dose-dependent fashion. Transmission electron microscopy (TEM) revealed that the cultured cells had ultrastructural features consistent with those of fetal hepatocytes. Scanning electron microscopy (SEM) showed that cells grown in either Medium 199 or EGF supplemented Medium 199 formed cellular aggregates within 6 h. The surface features of cells in control and experimental cultures were indistinguishable up until 24 h after exposure to EGF. …

Scanning Acoustic Microscopy In Materials Characterization, H. R. Vetters, P. Mayr, S. Boseck, Th. Luebben, R. Matthaei, A. Schulz

Scanning Electron Microscopy

The scanning acoustic microscopy is a powerful tool for subsurface imaging and therefore fault detection in coated parts. In this paper several methods are established to reveal the imaging of hidden structures. First efforts were made to find out the information depth due to the various distances between lens and surface of the object. By means of a specially developed test specimen it was possible to estimate the penetration depth for monitoring structural details. The indepth analysis of layered composites is considered by the determination of the V(z)-characteristics. Furthermore the gain of image processing by means of Fourier transformed patterns …

Use Of Polymer Casts Or Metal Particle Infusion Of Ducts To Study Antigen Uptake In The Guinea Pig Mammary Gland, D. I. Schenkman, D. T. Berman, R. M. Albrecht

Scanning Electron Microscopy

Microcorrosion casts were made of the duct system of guinea pig mammary glands by intramammary infusion of Mercox® polyester resin following involution of the glands after the first lactation. The acinar configuration of the involuted gland was apparent on examination of the casts by scanning electron microscopy (SEM). Surface features, which were readily identified as those of imprints of duct al epithelium, were visible at higher magnifications. The morphology of these casts corresponded to the patterns observed by SEM of ethanol cryofractured specimens of mammary tissue.

Cryofractured specimens of guinea pig mammary glands were also examined by SEM following intramammary …

Optical And Scanning Electron Microscopy In The Single Osteoclast Resorption Assay, Alan Boyde, Nadire N. Ali, Sheila J. Jones

Scanning Electron Microscopy

The present studies relate to the single or isolated osteoclastic resorption function assay which we introduced in 1983 to overcome objections to assays based upon measurements of calcium release from bones, in which it was never strictly controlled whether the mechanism involved the destruction of bone with the formation of classical Howship's lacunae. The method may prove to be quite popular in the near future and has already been adopted by other research groups. In previous work, we had utilised stereo-photogrammetry of scanning electron micrographs to measure the depth, volume and other parameters of the individual lacunae. However, increasing experience …

A Scanning Electron Microscopic Study Of Chromosomes And Nuclei, Kazuhiko R. Utsumi

Scanning Electron Microscopy

The fine structure of metaphase chromosomes and nuclei were studied by scanning electron microscopy. A coiled-coil structure of chromosomes was suggested by hypotonically unravelled chromosomes observed under light microscope. But chromosome preparations made for the light microscopic studies were not adequate for detailed examination with scanning electron microscope. Surface-spread chromosomes revealed that they were composed of nodular, twisted looping fibers of about 300 Å in diameter. Surface-spread nuclei were also composed of fibers identical to the chromosome fibers.

Segregation To Surfaces And Interfaces, Siegfried Hofmann

Scanning Electron Microscopy

The thermodynamics of segregation to surfaces and interfaces establish a framework of solute enrichment behaviour at equilibrium, depending on temperature and bulk concentration. It is represented by the Langmuir-McLean adsorption theory and its modifications. Solute-solute interactions in binary and multi-component systems allow a description of the occurrence of two-dimensional phases, of site competition of segregants and of cosegregation. The kinetics of segregation are mainly governed by the bulk diffusivity of the solute. Calculations of the segregation free energy based on surface energy differences of the components and on strain relief energy serve as a guideline for predictions of enrichment in …

Transmission Electron Microscopy Of Semiconductor Materials And Devices, R. B. Marcus

Scanning Electron Microscopy

This paper surveys the application of transmission electron microscopy (TEM) to semiconductor materials and device technology. A broad spectrum of TEM studies requires the preparation of either plan-view or vertical sections; these sections are made using mechanical abrasion, chemical etching or ion milling or a combination of these procedures. A survey is then given of applications of TEM to four classes of studies of semiconductor materials and devices: the configuration of device features, crystallographic defects, lattice and atomic resolution imaging, and the analysis of phase and chemical composition.

Correlation Between Fracture Mechanics Parameters And Fracture Characteristics In Austenites, A. Seibold, R. Löhberg

Scanning Electron Microscopy

Fracture surfaces of austenitic samples tested at room temperature show a correlation between fracture characteristics, Δ K-value and R-ratio: 1) at low Δ K-values up to 400 N/mm³/² and stress ratios of R = 0.1 and R = 0.7, no fatigue striations but fan-like features and flat facets can be seen; 2) fatigue striations, but no facets exist at Δ K-values greater than 900 N/mm³/² and R = 0.1; 3) at a higher stress ratio of R = 0.7 the facets disappear already at lower Δ K-values of about 650 N/mm³/^{2 …}

Sputter Crater Contour Mapping With Multilayered Films, L. L. Levenson, T. P. Massopust, J. Dick, M. C. Jaehnig, D. Griffith

Scanning Electron Microscopy

Multilayered films composed of alternating 200 Å Al and 267 Å Al203 layers are made by physical vapor deposition. Twenty-two pairs of these films are deposited on a polished Si wafer. Ion beam sputtering is used to form craters in the multilayered film. When a crater is viewed or photographed in situ by scanning electron microscopy, the Al₂O₃ layers appear bright and the Al layers appear dark. In the scanning electron microscope (SEM) the Al₂O₃ layers have a high secondary electron yield compared to Al. In secondary ion mass spectrometry (SIMS), using Cs^{+ …}

The Endothelium Of Initial Lymphatics During Postnatal Development Of The Rat Tongue, A. Castenholz

Scanning Electron Microscopy

The luminal surface of the subepithelial lymphatic plexus in the tongue of rats was investigated with SEM at different stages of postnatal development. In newborn and infant animals prominent and branched endothelial cells exhibit a conspicuous phenomenon producing a very irregular inner profile of the vascular wall. Among these cells the spindle-shaped type proves to be an essential component of the valve structures already found in few-day-old animals. There are also prominent cells with a polygonal appearance resembling histioblasts which form with their manifold processes, that partly extend into the lumen, an interlacing cellular pattern. The special morphological characteristics of …

Divergent-Beam X-Ray Diffraction In The Scanning Electron Microscopy And Its Use For The Study Of The Semiconductor Epitaxial Layers, J. Hejna

Scanning Electron Microscopy

Among the X-ray techniques belonging to the family of Kassel methods the divergent-beam diffraction method gives the best contrast for semiconductor specimens.

The technique has been accomplished in the scanning electron microscope (SEM) in a back reflection configuration. Epitaxial layers of GaAsSb and GaAsSbP on GaAs [100] oriented substrates were investigated. The diffraction lines from lattice planes giving only high Bragg angles were used. For the purpose of the layer strain analysis, the diffraction experiments were carried out for specimens placed horizontally (the lines {711} type recorded) and for tilted 45° (the lines {551) type recorded). A Cu foil was …

Multiple Paternity In A Territorial Passerine: The Bobolink, Thomas A. Gavin, Eric K. Bollinger

Faculty Research & Creative Activity

Electrophoretic and behavioral evidence corroborate the conclusion that Bobolink (Dolichonyx oryzivorus) females occasionally copulate with more than one male, which results in the insemination of a single clutch of eggs by those males. In 2 of 12 families from which blood samples were obtained from the mother, the putative father, and the nestlings, at least 2 males were responsible for fertilization of the clutch. We believe this is only the second bird species in which multiple paternity has been documented conclusively in the wild. Our speculation that it may not be uncommon leads to a caution for evolutionary biologists who …

Multiple Paternity In A Territorial Passerine: The Bobolink, Thomas Gavin, Eric Bollinger

Faculty Research & Creative Activity

Electrophoretic and behavioral evidence corroborate the conclusion that Bobolink (Dolichonyx oryzivorus) females occasionally copulate with more than one male, which results in the insemination of a single clutch of eggs by those males. In 2 of 12 families from which blood samples were obtained from the mother, the putative father, and the nestlings, at least 2 males were responsible for fertilization of the clutch. We believe this is only the second bird species in which multiple paternity has been documented conclusively in the wild. Our speculation that it may not be uncommon leads to a caution for evolutionary biologists who …

Going To Extremes: Why Do Sanderlings Migrate To The Neotropics?, J. P. Myers, John L. Maron, Michel Sallaberry A.

Biological Sciences Faculty Publications

Sanderlings (Calidris alba) breed within a small latitudinal range in the arctic while spreading in winter virtually throughout temperate and tropical marine beaches of the world. This paper examines spatial variation in Sanderlings nonbreeding density across the New World, documents annual cycle differences between populations wintering in California and those wintering in Peru and Chile, and then explores demographic and ecological factors underlying Sanderlings migration to different wintering grounds. Densities during the nonbreeding season are higher on the Pacific coast than on the Atlantic at all censused latitudes in the New World, and reach a peak in southwestern …

Seasonal Changes In Feeding Success, Activity Patterns, And Weights Of Nonbreeding Sanderlings (Calidris Alba), John L. Maron, J. P. Myers

Biological Sciences Faculty Publications

Seasonal changes in Sanderling (Calidris alba) feeding success, time budgets, and weights were followed throughout the nonbreeding season at Bodega Bay, California. Sanderlings spent more time roosting in fall than in winter, and in fall adults spent more time roosting than juveniles. Sanderling prey capture rates were high in fall and spring and declined through winter. Sanderling weights paralleled seasonal changes in feeding success and activity patterns: birds were heaviest in fall and spring and lightest in winter. These results reflect lowered food availability in winter and imply that birds may have difficulty balancing their energy budgets during …

Secondary Electron Imaging In The Scanning Transmission Electron Microscope, R. M. Allen

Scanning Electron Microscopy

The detailed correlation of surface morphology and subsurface microstructure has been made possible by the scanning transmission electron microscope. This instrument provides the capability for simultaneous and independent secondary electron and transmitted electron imaging from the same sample area. This includes the ability to generate mixed secondary/transmitted electron images, which form a concise visual presentation of the information in the two component images.

Correlative surface and through-volume specimen examination of this type has most frequently been applied to backthinned samples, which are specifically prepared in a way which produces electron-transparent material in the immediate vicinity of a surface of interest …

Applications Of Laser Microprobe Mass Analysis For Characterization Of Asbestos, J. K. De Waele, F. C. Adams

Scanning Electron Microscopy

Laser microprobe mass analysis with the commercial LAMMA-500 (transmission type) instrument when utilized in laser desorption conditions provides information which allows the identification of particular asbestos varieties, in various types of samples, including lung tissue. Also it has detection capability of adsorbed organic material and it is a valuable tool for the study of the surface of chemically modified asbestos fibers manufactured by silanation or through phosgene treatment (chrysophosphate). Recent progress within our laboratory is discussed, and shortcomings of the methodology are indicated.