Digital Commons Network^™

Enamel Structure In Odontocete Whales, M. Ishiyama

Scanning Microscopy

With regard to the enamel structure of mammals, a large number of studies have been reported in the past. Of them, however, the enamel structure of odontocetes has not yet been sufficiently elucidated. The author therefore observed the enamel structure of 11 species in 7 families of living odontocetes.

A clear prism structure in the enamel is noted in delphinids and Pontoporia blainvillei. Neophocaena phocaenoides has a very simple-structured prism, but even this structure is obvious only in the deep layer of the enamel, disappearing gradually from the mid layer to surface layer.

The prism pattern of delphinids differs …

Is There A Calcification Factor Common To All Calcifying Matrices?, E. Bonucci

Scanning Microscopy

This paper reviews the principal morphological findings pertinent to the early phases of the calcification process and explores the possibility that there may be a calcification factor common to all calcifying matrices. Three structures have a main role in calcification: collagen fibrils, matrix vesicles, and crystal ghosts. Only crystal ghosts are present in all calcified tissues, so that only they can be taken into consideration as a common calcification factor. They are organic molecules which have the same morphology as that of the inorganic structures present in the calcified matrix, which means that they can be considered as templates for …

Observation Of Tungsten Field Emitter Tips With An Ultra-High Resolution Field Emission Scanning Electron Microscope, Katsuhiro Kuroda, Shigeyuki Hosoki, Tsutomu Komoda

Scanning Microscopy

Tungsten emitter tips are observed with a prototype scanning electron microscope with an approximate SA electron beam size at an accelerating voltage of 30kV. A field emission electron source and in-lens type objective lens are incorporated into the electron column. A special specimen stage was designed to clean the emitter tips using a flashing operation and to reduce contamination by heating them during the observation. The observed emitters were W< 011 >, W< 001 > and Ti/W< 001 >. The crystallographic planes were clearly visible in the W< 011 > and W< 001 > observation. It was also possible to observe atomic layer steps of 4.5A during the …

Mineralization Of Normal And Rachitic Chick Growth Cartilage: Vascular Canals, Cartilage Calcification And Osteogenesis, Irving M. Shapiro, Alan Boyde

Scanning Microscopy

This paper reviews recent work in the authors' laboratories that has led to new observations and thoughts concerning the mineralization of normal and rachitic chick growth cartilage. The proximal tibial growth cartilages of normal and rachitic chicks were rapidly frozen and prepared for SEM and biochemical studies. Using a scanning microfluorimetric technique we showed that at the mineralization front of normal and rachitic cartilage there is an abrupt change in chondrocyte metabolism. Thus cells in this region exhibited an increase in NADH and oxidative metabolism. In rickets, there was a decrease in the reduced pyridine nucleotide content of each of …

Utilization Of Immunogold Labeling To Compare The Adsorption Behavior Of Fibrinogen, Fibronectin And Albumin On Polymers, K. D. Murthy, A. R. Diwan, S. R. Simmons, R. M. Albrecht, S. L. Cooper

Scanning Microscopy

Immunogold labeling followed by scanning electron microscopy (SEM) was used to examine the surface distribution of adsorbed plasma proteins. Adsorption was performed under various conditions on six different polymers; [low density polyethylene (PE), chromic acid-oxidized PE (OXPE), solution grade Biomer® (SB), Teflon-(FEP)®, a laboratory synthesized polyurethane containing some zwitterions (ZW) and a polydimethylsiloxane based polyurethane (ZS) also containing zwitterions]. The proteins used were purified human and canine fibrinogen, fibronectin, and serum albumin. The immunogold staining technique was successful in the labeling of the adsorbed proteins. The adsorbed proteins were distributed differently on the polymers selected. Human and canine fibrinogen were …

Electron Microscopy And Glycosaminoglycan Histochemistry Of Cerebellar Stellate Neurons, O. J. Castejón, H. V. Castejón

Scanning Microscopy

The stellate neurons of the cerebellar molecular layer have been mostly studied by light and transmission electron microscopy (TEM). However, the freeze-fracture scanning electron microscopy (SEM) and glycosami noglycan histochemistry of these inhibitory microneurons have not been explored thus far. The freeze-etching technique, the freeze-fracture method for SEM and the conventional techniques for TEM were applied to cerebellar samples of Swiss albino mice and Arius spixii teleost fishes. In addition, Alcian Blue (AB) staining was applied to mouse cerebellar tissue in order to study glycosaminoglycan histochemistry. At the SEM level, the stellate neurons showed a short axonal plexus extending to …

The Application Of An Improved Laser Microprobe In Art Analysis, Gary W. Carriveau, Lin Chang-Shan, David M. Coleman

Scanning Microscopy

The laser microprobe has many features which would seem to make it an ideal tool for analysis of art objects. These include high spatial resolution, extremely small sample requirements, a wide variety of possible elements for analysis over a large dynamic range of concentrations and capability of sampling a variety of sizes and shapes. Problems of surface damage, spectral insensitivity, and poor accuracy and precision had limited the applicability of this technique in the past. Following a systematic study of these limitations, improved performance has been achieved. In addition, a mathematical model of the sampling process has been developed in …

Micromorphological Characterisation Of Normal Human Bone Surfaces As A Function Of Age, S. A. Reid

Scanning Microscopy

Endosteal surfaces of human bone specimens, principally from the sixth rib, from subjects ranging in age from seven weeks to 87 years were studied using the secondary electron imaging mode in the scanning electron microscope. Specimens were examined after the removal of cells only, or after the removal of cells and organic matrix.

Morphological differences made it possible to identify the age group to which a specimen belonged. The most obvious of these was the ratio of active to resting bone surfaces, which decreased with age. The organisation of the collagen matrix which was deposited at endosteal surfaces was different …

Distinguishing Adult Pectinophora Scutigera (Holdaway) According To Larval Diet By X-Ray Microanalysis, R. A. Lewis, P. W. Walker

Scanning Microscopy

In an exploratory study using scanning electron microscope (SEM) based energy dispersive spectroscopy (EDS) of X-rays, differences were detected in the elemental compositions of adult Pectinophora scutigera raised on contrasting diets - cotton, Hibiscus tiliaceus and laboratory medium.

X-ray spectra were collected from the thorax and abdomen of 13 male and 13 female moths. X-ray yields are optimised by ashing the insects for 1 h at 400-600°C, and by operating the SEM at 25 kV.

Spectrum matching, element matching, discriminant analysis and principal components analysis were used to classify the specimens on the basis of diet with 54-100% success. Spectra …

The Intermediate Filament Cytoskeleton Of Macrophages, L. Phaire-Washington, G. Howard-Robinson, J. Lucas, J. Roberson, E. Brako, N. Mcneil, S. Williams, C. Watson, T. Igbo, L. Brako, P. Farshori, V. Cannon

Scanning Microscopy

This study characterizes two-and three-dimensional ultrastructure and surface topography of polymerized networks of intermediate filaments (IF) isolated from mouse peritoneal macrophages. Isolated IF bound to monoclonal anti-IF antibodies in enzyme-linked immunosorbent assays. Immunogold labeling of IF with specific antibodies revealed that epitopes are distributed along filaments particularly at junctions where filaments interconnect. Networks of IF, viewed by scanning electron microscopy, organized as ropelike groups of interconnecting filaments which swirl and encircle each other to form three-dimensional lattices containing ellipsoidal-, circular-, and vacuole-shaped cavities. Cavity diameters were similar in size to organelles and vacuoles; diameters were grouped as small (12-288 nm), …

A Comparative Study On In Vitro Invasion Rates By Melanoma Cells In The Human Amniotic Basement Membrane Model Versus In Vivo Tumor Nodule Formation In C57bl6 Mice, B. Persky, G. W. Chmielewski

Scanning Microscopy

Invasion by murine B16-F10 melanoma cells was studied using the human amniotic basement membrane (HABM) assay. B16-F10 cells were collected after a single passage through the amnion and grown to near confluency. The cycle of plating, passaging, collecting, and culturing B16-F10 cells was repeated five times. The invasion rate for B16-F10 cells remained relatively unchanged after six passages through the amnion. Injection of first-passage B16-F10 cells into C57BL6 mice resulted in 29 lung tumors per animal whereas sixth-passage cells resulted in 300+ lung tumors. While there exists no correlation of the number of cells penetrating the amnion with colonization number, …

Study Of Rat Lung Alveoli Using Corrosion Casting And Freeze Fracture Methods Coupled With Digital Image Analysis, Alan C. Nelson

Scanning Microscopy

Relative areas and volumes can be estimated from vascular corrosion casts of rat lung alveoli using a calibration obtained from bulk frozen hydrated tissue. These morphometric measurements are roughly independent of the shrinkage and distortion artifacts known to arise in the corrosion casting procedure. Digital image processing of the SEM micrographs is employed to facilitate the measurement of casts and frozen tissue.

The vascular corrosion casting technique is modified also to permit successful casting of alveolar air passages. The modified technique produces faithful casts of dead-ended luminal structures where continuous perfusion of casting medium into the tissue is not possible. …

Morphometric Changes As A Function Of The Proliferative Status Of Murine Mammary Carcinoma Cells, Linda S. Yasui, Lyle A. Dethlefsen

Scanning Microscopy

Ultrastructural analysis was performed to determine morphological changes in the 67 murine mammary tumor cells grown in four defined metabolic states in vitro, i.e., proliferating cells (P), cells in transition towards quiescence (T), nutrient-deprived quiescent cells (Q_I), and Q_I cells stimulated to reenter the cell cycle (St₄) by refeeding for 4h in situ with complete medium. Also, these documented changes were evaluated as a function of the radiosensitivity of the various cell types. The average number of lipid body and mitochondrial profiles per cell was significantly higher in Q_I and St₄ cells …

Cracks In Fossil Enamels Resulting From Premortem Vs. Postmortem Events, John M. Rensberger

Scanning Microscopy

Vertebrate enamel preserves a record of fracture-producing strain. Fracturing during the life of the individual is potentially a source of selection for stronger enamel in the course of evolution. To determine if it is possible to recognize such fractures in fossil enamel, cracks in a variety of fossil materials, including enamel-covered holostean scales, crocodilian teeth, theropod and hadrosaurid dinosaur teeth, and mammalian teeth were examined. Cracks that occurred during the life of the individual could be recognized by abrasive wear on edges exposed at the surface of the enamel in areas worn by oral or locomotor abrasion. Certain distinctive crack …

Immunogold Labeling Of Human Leukocytes For Scanning Electron Microscopy And Light Microscopy: Quantitative Aspects Of The Methodology, E. De Harven, D. Soligo

Scanning Microscopy

When cell surface antigens are labeled with the colloidal gold marker, backscattered electron images (BEI) reveal all the gold particles and, therefore, permit total counts. Secondary electron images (SEI) show only a small percentage of the gold particles and are inadequate for quantitative evaluation.

For determination of the cellular labelinq index, a time-consuming method implies the screening of 100 cells by scanninq electron microscopy, at a magnification of approximately 12,000 to 15,000x, with continuous SE/BE shifts. A much more efficient method is to transfer the SEM sample or its equivalent under the light microscope and to count the total number …

Three Dimensional Secondary Ion Mass Spectrometry Imaging And Retrospective Depth Profiling, D. R. Kingham, A. R. Bayly, D. J. Fathers, P. Vohralik, J. M. Walls, A. R. Waugh

Scanning Microscopy

Secondary Ion Mass Spectrometry (SIMS) for three dimensional analysis of materials is an exciting and rapidly developing technique. We describe a framestore datasystem for ion microprobe instruments and present images and three dimensional SIMS data acquired and processed with this system. The concept of retrospective depth profiling is introduced, particularly as a means to optimise concentration detection limits. We examine the dependence of concentration detection limits on spatial resolution.

Assembly And Alignment Of Fibronectin-Coated Gold Beads Into Fibrils By Human Skin Fibroblasts, Donna M. Pesciotta Peters, Deane F. Mosher

Scanning Microscopy

The assembly of fibronectin into fibrils was monitored by high voltage electron microscopy using 18 nm colloidal gold beads bound to fibronectin (Au₁₈-fibronectin) or an amino terminal 70 kd fragment of fibronectin (Au₁₈-70 kd) that blocks the incorporation of fibronectin into disulfide bonded fibrils. Subconfluent cultures of human skin fibroblasts were incubated with the colloidal gold complexes for 0.25, 0.5, 1.5 and 5 h. In fibroblast cultures incubated with Au₁₈-fibronectin and Au₁₈-70 kd fragments for 0.25 and 0.5 h, the complexes of Au₁₈-fibronectin and Au₁₈-70 kd fragment were …

Morphological Criteria For Comparing Effects Of X-Rays And Neon Ions On Mouse Small Intestine, K. E. Carr, T. L. Hayes, M. Indran, S. J. Bastacky, G. Mcalinden, E. J. Ainsworth, S. Ellis

Scanning Microscopy

Several techniques have been used to assess changes in different parts of mouse small intestine three days after a single dose of either 16.5 Gy X-rays or 11 Gy neon beam. The doses were chosen to be approximately equivalent in terms of their effect on the number of microcolonies present.

In qualitative terms, villous damage was seen after both types of radiation exposure: collared crypts, similar to those seen in biopsies taken from patients suffering from coeliac disease, were conspicuous after neon irradiation.

In semi quantitative terms the doses used, although estimated from previous work to give biologically equivalent damage, …

Expression Of Major Histocompatibility Complex Antigens On Macrophages: Correlative Study Using Flow Cytometry, Radioimmunoassay, And Colloidal Gold Immunolabeling, Lynne E. Guagliardi, Donna M. Paulnock, Ralph M. Albrecht

Scanning Microscopy

Correlative scanning electron microscopy (SEM), radioimmunoassay (RIA), and flow cytometric analysis were used to characterize levels of class I and class II major histocompatibility complex-encoded (MHC) antigen expression on peritoneal exudate cells of mice chronically infected with Chlamydia psittaci. Analysis of peritoneal macrophages by all three techniques revealed a marked induction of H-2 K,D (class I) and I-A, l-E (class II) antigens on cells from infected C3H mice when compared to uninfected controls.

Scanning electron micrographs further document that the increases in class I and II MHC antigens are due to an increase in la/H-2 bearing cells as well …

The Effect Of Controlled Diffusion Of Ions On The Formation Of Hydrated Calcium Oxalate Crystals, H. Lachance, R. Tawashi

Scanning Microscopy

Calcium oxalate monohydrate (COM), calcium oxalate dihydrate (COD) and calcium oxalate trihydrate (COT) were grown from solutions under controlled release of the reacting ions. The mass transfer kinetics of ions released from an insoluble polyethylene matrix, from an osmotic pump system and from the hydrolysis of diethyl oxalate were studied under different experimental conditions. It was possible with simple laboratory techniques to grow well-formed crystals of COM, COD and COT, suitable for single crystal work. Results obtained show that the degree of hydration, size, and morphology of the crystals formed, are controlled by interfacial kinetic factors.

Electron Energy Loss Spectroscopy And Biology, C. Jeanguillaume

Scanning Microscopy

Although most of the recent work concerning EELS in electron microscopy is related to instrumental developments, there are a number of papers relating to biological applications. The aim of this paper is to attempt to present in a pedagogical manner the subject of EELS and biology. The biologist will be taught about EELS and the physicist about the possible biological applications of this technique. The paper thus consists of: 1) a presentation of a minimum background on EELS required for biologists to realize what its potential is; 2) a description of why EELS is a useful tool in biology; 3) …

Correlative Light And Electron Microscopy Of Platelet Adhesion And Fibrinogen Receptor Expression Using Colloidal-Gold Labeling, Steven L. Goodman, Ralph M. Albrecht

Scanning Microscopy

Differences in the shape change responses of platelets to various polymers may determine the thrombotic potential of these materials. Substrate-dependent variation in the expression and motility of the platelet fibrinogen receptor may underlie these differences due to this ligand's essential role in platelet aggregation. In this study we examine platelet activation on polyetherurethaneureas (PEUUs) presently being evaulated for vascular prosthetic applications. These polymers are prepared as 50-100nm thin films suitable as substrates for consecutive light microscopy, high voltage electron microscopy (HVEM), and SEM. 18nm colloidal gold coupled to fibrinogen permits visualization of that receptor's motility in living cells by video-enhanced …

Immuno-Scanning Electron Microscopy Of Normal And Leukemic Leukocytes Labeled With Colloidal Gold, D. Soligo, G. Lambertenghi-Deliliers, E. De Harven

Scanning Microscopy

The immunogold method, utilizing 40 nm colloidal gold particles which can be selectively visualized with the scanning electron microscope (SEM) in the backscattered electron imaging mode was used for the study of blood cells incubated with various monoclonal antibodies. Numerous antileukocyte monoclonal antibodies still recognize lightly glutaraldehyde prefixed antigens and can be used to identify various blood cell types and even to recognize their different maturation stages.

Clearcut differences in surface morphology exist among peripheral blood normal leukocytes and even among the principal lymphocyte subclasses. Marked heterogeneity in surface morphology is, on the other hand, evident when studying precursors or …

The Cytotoxic Effects Of Trimethylpentane On Rat Renal Tissue, William N. Norton, David R. Mattie

Scanning Microscopy

The primary objective of the investigation was to determine the acute cytopathologic effects of 2,3,4 -trimethylpentane, a major constituent of gasoline, on renal tissue of the mature male rat. Three groups of 9 Fischer-344 rats each were administered trimethylpentane by gavage twice weekly for 7, 14, or 28 days at a concentration of 1.5 ml/kg body weight. The tissues were fixed by perfusion, and subsequently processed for scanning and transmission electron microscopy. Al though the manifestations of hydrocarbon toxicity were evident in all experimental tissues examined, the extent and magnitude of cellular lesions increased as the exposure period progressed. The …

Unsteady Flow Modeling Of The Releases From Glen Canyon Dam At Selected Locations In The Grand Canyon, Jerold F. Lazenby

Elusive Documents

No abstract provided.

An Electron Spin Resonance Study Of Stearic Acid Interactions In Model Wheat Starch And Gluten Systems, L. E. Pearce, E. A. Davis, J. Gordon, W. G. Miller

Food Structure

Electron spin resonance (ESR) was used to examine interactions of 16- Doxyl stearic acid in wheat starch-water (starch:water "'1: 1), vital wheat gluten-water and glut en-starch-water model systems, Immobilization of the 16-Doxyl stearic acid, shown by broadIine ESR powder patterns , occurred in wheat starch model systems. In contrast to the starch systems, 16-Doxylstearic acid in gluten-water systems did not display broad line powder patterns. Broadened 3- line ESR spectra were recorded for the gluten-water-16- 0oxyl stearic acid, Th is result was probably due to s pin probe which was bound, and spin probe which was bound in different water …

Food Microstructure

Food Structure

No abstract provided.

Food Microstructure

Food Structure

No abstract provided.

Insites, Winter 1987, Utah State University

inSites

Magazine of the Department of Landscape Architecture and Environmental Planning

Scanning Electron Microscopy Studies Of The Cellular Changes In Raw, Fermented And Dried Cocoa Beans, A. S. Lopez, P. S. Dimick, R. M. Walsh

Food Structure

Cocoa beans are submitted to a curing process of fermentation and drying to develop flavor precursors . The beans must have reached maturity; otherwise, no amount of processing can produce the desired flavor . Early work with cacao cell cultures showed that only when the cells have "matured" co uld a chocolate or cocoa flavor result from further processing. Fermentation is therefore required because unfermented beans may develop little chocolate flavor when roasted . likewise , the outcome of excessive fermentation may also result in unwanted flavor . Thus , the first major post - harvesting phase t o have …