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High Resolution Scanning Auger Microscopy Of Mineral Surfaces, M. F. Hochella Jr., A. M. Turner, D. W. Harris

Scanning Electron Microscopy

There are a number of cases where scanning Auger microscopy can be used to determine the near-surface composition of minerals with extremely high lateral resolution. This involves collecting Auger spectra with reasonable signal to noise ratios without encountering significant beam induced charging or surface degradation, even if the beam is impinging on a grain less than 1μm in diameter. We typically use a 3 keV beam with less than 10 nA beam current on a sample surface that is tilted (to increase backscattered and secondary electron emission efficiency) and relatively flat. To further minimize surface degradation, vacuum levels are kept …

Quantitative Ion Microprobe Analysis Of The Rare Earth Elements In Minerals, Ghislaine Crozaz, Ernst Zinner

Scanning Electron Microscopy

The lanthanides or rare earth elements (REE) which are present in trace concentrations in rocks are most useful for investigating the origin of these objects. Of the microbeam techniques presently used to measure the REE concentrations of individual crystals, secondary ion mass spectrometry (SIMS) is the only method sensitive enough to allow the determination of REE abundances in most natural minerals. Usually, energy filtering is applied to remove all complex molecular interferences. All the REE, down to a level of ≤ 100 ppb, can be measured in spots 5 to 20 𝜇m in diameter. A growing number of studies involving …

Intrauterine Device (Iud) Associated Pathology: A Review Of Pathogenic Mechanisms, Waldemar A. Schmidt, Karmen L. Schmidt

Scanning Electron Microscopy

This paper summarizes our studies of IUD-related disease with those previously published by others. Our data are based upon 51 IUDs and 42 index cases of IUD-related disease demonstrating specific processes. Gross, dissecting microscope, scanning electron microscope and X-ray microanalysis examinations were made of selected IUDs and associated tissues. Tissue associated with the IUDs revealed inflammation in 59.4%, calcific material in 6.3% and no abnormality in 34.4%. JUD-associated tissue responses were accompanied by changes of the IUD; these changes involved deposition of substances upon the IUD surface and degradation of the JUD itself. Disintegration of the IUD, its string or …

Structural Features Of Isolated, Fractionated Bone Marrow Endothelium Compared To Sinus Endothelium In Situ, Seiji Irie, Mehdi Tavassoli

Scanning Electron Microscopy

Structural features of isolated, fractionated rat bone marrow endothelium were compared to those of marrow sinus endothelium in situ. Marrow endothelium was purified, first by density gradient sedimentation on Percoll and then subjected to centrifugal elutriation. Using antifactor VIII antibody staining (indirect immunofluorescent method), preparations of greater than 50% purified endothelium were obtained. By SEM, these cells were about 10 μm in size and showed smooth surface and numerous invaginations. These features were also observed in the in situ endothelium obtained by perfusion-fixation and freeze-cracking. In addition, in situ endothelium displayed numerous hemopoietic cells in migration through the endothelium. By …

Scanning Electron Microscopy Of The Microvascular System In The Inner Ear, Yoshiaki Nakai, Haruhiko Masutani, Hiromasa Cho

Scanning Electron Microscopy

In the present work, vessels casts in the inner ear of the rat and guinea pig, prepared by casting method using Mercox resin, were subjected to scanning electron microscopic examination and following results were obtained: 1) In adult guinea pig, numerous capillary nets were found in the following parts: stria vascularis, spiral ligament, spiral prominence, Corti's organ, spiral ganglion, plexus cochlearis, semicircular ampulla, saccule, utricle, and endolymphatic sac. These were consistent with functionally and morophologically important areas in the inner ear. 2) In the central side of the area with capillary nets, arterioles were found to run throughout, like a …

Scanning And Transmission Electron Microscopic Study Of Recovered Porcine Aortic Valved Conduits, D. J. Allen, I. H. Fentie, J. T. Davis, Angela Lineen

Scanning Electron Microscopy

Four explanted porcine aortic valved conduits were examined using scanning and transmission electron microscopy. Sources of obstruction such as neointima or "peel" and calcification were observed. In one sample the neointima was found to possess an unusually large expanse of squamous cells partially lining the luminal surface. This lining much resembled a normal endothelium, which is not an expected feature of neointima. Cells, presumably of host origin, were noted upon the leaflet surfaces. They did not seem as well organized as those found on the neointima. Calcification did not seem greatly advanced but was clearly apparent. Certain treatments proposed by …

Statoconia Formation In Molluscan Statocysts, Michael L. Wiederhold, Christine E. Sheridan, Nancy K. R. Smith

Scanning Electron Microscopy

The gravity sensors of all molluscs phylogenetically below the cephalopods are spherical organs called statocysts. The wall of the sphere contains mechanosensory cells whose sensory cilia project into the lumen of the cyst. The lumen is filled with fluid and dense "stones", the statoconia or statoliths, which sink under the influence of gravity to load, and stimulate, those receptor cells which are at the bottom. The statuconia of Aplysia californica are shown to be calcified about a lamellar arrangement of membranes. Similar lamellar membrane arrangements are seen within the receptor cells, and their possible role in the formation of the …

Cells From Xenopus Laevis Gastrulae Adhere To Fibronectin-Sepharose Beads And Other Lectin Coated Beads, Kurt E. Johnson, Michael H. Silver

Scanning Electron Microscopy

Cells from Xenopus laevis blastulae have a poorly developed ability to adhere to Sepharose beads covalently coupled to bovine plasma fibronectin (FN-beads). They do, however, have the ability to adhere to con A-beads and cytodex-1 and cytodex-3 beads. Beginning at the early gastrula stage, there is a progressively increasing ability of cells to adhere to FN-beads. Gastrula cells adhere to FN-beads by the formation of large ruffling lamellipodia. These cells can translocate on the surface of FN-beads; and when attached to both beads and the surrounding glass substratum of culture vessels, have the ability to move the beads extensively. Gastrula …

Adverse Effects Of Metals On The Alveolar Part Of The Lung, Anne Johansson, Per Camner

Scanning Electron Microscopy

Rabbits were exposed to low levels of metal dust or metal ions by inhalation for 1-8 months, 5 days/week and 6h/day. Following exposure lung tissue was examined by light and electron microscopy, the lung content of phospholipid was analyzed and the morphology and function of alveolar macrophages were investigated.

Metallic nickel dust as well as soluble nickel chloride produced accumulation of macrophages and laminated structures in alveoli and increased volume density of alveolar type II cells. The amount of phospholipids was elevated, mainly due to an increase in disaturated phosphatidylcholine. After one month exposure to metallic nickel dust or soluble …

Comparative Aspects Of Mammalian Spermiogenesis, Leif Plöen, Jean-Luc Courtens

Scanning Electron Microscopy

The testes of some different orders of eutherian mammals were examined by conventional electron microscopy with respect to their pattern of spermiogenesis. In addition, some of the testes were studied by cytochemical methods for demonstration of certain nuclear proteins and of glycoproteins in the acrosome and the plasma membrane of spermatids.

It was found that although the basic pattern of spermiogenesis was similar in all species studied, there were pronounced dissimilarities in the final shape of the spermatids. Differences were also observed in the timing of the differentiation of several organelles. The head of late spermatids and spermatozoa of Primates, …

Intracellular Structure Of The Outer Hair Cell Of The Organ Of Corti, Y. Harada, T. Sakai, N. Tagashira, M. Suzuki

Scanning Electron Microscopy

The intracellular structure of the outer hair cells of the normal guinea pig organ of Corti was investigated three dimensionally by scanning electron microscope. Freeze fracturing technique followed by maceration with a 0.1% OsO₄ solution (osmic maceration method) was used. Among the cell organelles, the endoplasmic reticulum (ER) showed the most interesting features, such as subsurface cisternae and lamellar bodies. The subsurface cisterna which formed a stratiform network covered the inner surface of the cell membrane and the stratiform structure disappeared at the infranuclear region. Variously shaped mitochondria (spherical, cylindrical and branched) were found on the innermost layer of …

Scanning Electron Microscopic Observation Of The Crista Ampullaris, Y. Harada, M. Takumida, N. Tagashira

Scanning Electron Microscopy

The crista ampullaris of the guinea pig and the bull frog were investigated by scanning electron microscopy. The crista ampullaris were freeze fractured or sheared followed by maceration with 0.1% OsO₄ solution. Following this, three-dimensional intracellular structures were observed. The mitochondria of the sensory cells varied in shape from globular to long and slender. Golgi apparatus and endoplasmic reticulum of the sensory cells were also demonstrated clearly. Nerve elements, nerve endings and synaptic structures were also observed stereoscopically.

Joan Staats Oral History, Joan Staats

Personal Papers Collection

No abstract provided.

Current Filament Formation In Gold Compensated Silicon Pin Diodes, H. Baumann, T. Pioch, H. Dahmen, D. Jäger

Scanning Electron Microscopy

In semiconducting materials with current controlled negative differential conductivity an inhomogeneous current density distribution can arise leading to a well-defined spatial pattern in the form of current filaments. Detailed experiments are performed on silicon pin diodes showing a pronounced multistability in the current voltage characteristics. By using the voltage contrast and the electron beam induced voltage (EBIV) methods in a SEM, it is confirmed that each jump in the current is accompanied with the formation or disappearance of a well defined transverse electrical structure between the two contacts as a result of a current filament. This non-uniform state of the …

Ultrastructural Studies Of Intercellular Contacts (Junctions) In Bone Marrow. A Review, Ferrell R. Campbell

Scanning Electron Microscopy

This paper reviews ultrastructural studies of the intercellular contacts or junctions between cells of the bone marrow. Studies using tannic acid and glutaraldehyde as a fixative have shown pentalaminar complexes between many types of cells in marrow of mice and chicks. These intercellular contacts occur between adjacent stromal cells, between stromal cells and developing blood cells and, in marrow of mice, between migrating blood cells and cells of the sinusoidal wall. Because of their location and widespread occurrence, it is believed these contacts may represent a type of adherent junction helping to maintain an orderly arrangement of blood cells and …

Ultrasonic Microdissection Of Immature Intermediate Human Placental Villi As Studied By Scanning Electron Microscopy, Gregory J. Highison, F. Donald Tibbitts

Scanning Electron Microscopy

The human placenta during the first 20 weeks of gestation undergoes rapid and extensive morphological changes. Near the end of this period, the most predominant type of villus present is the immature intermediate placental villus. In order to visualize this complex structure with scanning electron microscopy (SEM), we have developed a microdissection technique to expose tissue components of the placental villus while retaining its normal histological architecture. Placental villi were initially fixed in Karnovsky's fixative, buffered formalin, or 2% osmium tetroxide solution prior to exposure to connective tissue enzymes or detergents alone or in combination. Samples were dehydrated through 100% …

Scanning Electron Microscopy In The Evaluation Of Consolidation Treatments For Stone, A. E. Charola, R. J. Koestler

Scanning Electron Microscopy

The use of scanning electron microscopy (SEM) examination is shown to be an important tool in the evaluation of the effectiveness of consolidant treatments in stone. This implies the visualization of the attachment of the resin to the stone, the assessment of the degree of penetration and the distribution of the resin in the stone matrix. These factors can then be correlated with the chemical nature of the stone and the resin.

A sample preparation technique for limestone, based on acid etching of the surface, is described. This technique improves the visualization of the resin within the stone.

The Characteristic Structural Features Of The Blood Vessels Of The Lewis Lung Carcinoma (A Light Microscopic And Scanning Electron Microscopic Study), T. W. Grunt, A. Lametschwandtner, K. Karrer

Scanning Electron Microscopy

Vascular corrosion casts of Lewis lung carcinomas (LLC) grown subcutaneously in C57BL/6-mice are correlated with histological sections and with tumor tissue prepared for scanning electron microscopy (SEM). By making low, medium and high pressure cast preparations we studied the influence of perfusion and injection pressure on the resulting cast sample.

Three types of vascular proliferations are distinguishable in LLC: 1) Small globular outgrowths on sinusoidal dilated tumor capillaries, caused by proliferation of their endothelial cells. 2) New sprouts on surrounding host vessels, invading the small, still avascular implant. 3) Superficially located, centrifugally running sprouts in peripheral regions of large tumors. …

The Angioarchitecture Of The Lewis Lung Carcinoma In Laboratory Mice (A Light Microscopic And Scanning Electron Microscopic Study), T. W. Grunt, A. Lametschwandtner, K. Karrer, O. Staindl

Scanning Electron Microscopy

53 Lewis lung carcinomas implanted subcutaneously into C57BL/6-mice were examined. The animals were killed at various stages of tumor growth (TG) and prepared for histology and for scanning electron microscopy (critical-point-dried tissue; vascular corrosion casts). Prior to casting animals were rinsed using different perfusion pressures. Casting was done by manual injection of the resin, whereby different influx-rates were applied resulting in low, medium and high pressure preparations.

We discern 3 phases of tumor angiogenesis (TA) occurring during 4 stages of TG among which vasodilation establishes the first reaction of the host vascular system to a growing tumor implant. During this …

Ua66/6/2 Alumni Newsletter, Wku Biology

WKU Administration Documents

Newsletter created by and about the WKU Biology department highlighting students, faculty and alumni activities.

Factors Affecting Epithecal Growth Lines In Four Coral Species, With Paleontological Implications, Jean-Luc Liénard

Loma Linda University Electronic Theses, Dissertations & Projects

The number of epithecal (external) growth lines was surveyed over 124 days for Montastrea annularis growing at different depths (3.5 m to 61 m). There was a significant (P< .01) decrease in the number of lines with depth. Although the linear regression is significant, there is evidence for a logarithmic or quadratic relationship, and more data from greater depths are needed to determine which of these gives a better fit.

The number of growth lines formed during light-dark cycles of 16, 24 and 32 hours were compared for M. annularis, M. cavernosa, Porites astreoides and Tubastrea aurea. The variability among colonies from the same species was in many cases more significant than that among light treatments. This is a serious problem for anyone counting lines in corals, especially from a few specimens; therefore conclusions based on such counts seem hazardous on …

Models Of Disuse: A Comparison Of Hindlimb Suspension And Immobilization, Robert H. Fitts, Joseph Mark Metzger, Denise A. Riley, B. R. Unsworth

Biological Sciences Faculty Research and Publications

The effects of 1 and 2 wk of hindlimb suspension (HS) on rat skeletal muscle function were determined and the results compared with those obtained previously with hindlimb immobilization (HI). Both models of disuse (HS and HI) primarily affected slow-twitch muscle. Each decreased the isometric twitch duration in the slow-twitch soleus; however, the HS-mediated effect was entirely a result of a shortened contraction time (CT), whereas HI reduced one-half relaxation time (½RT) as well as CT. Soleus muscle mass and peak tetanic tension (P₀) declined with disuse. The HS effect on muscle mass and P₀ was variable, …

Changes In Absorptive Surfaces Of Rat Visceral Yolk Sac With Increasing Gestational Age, W. P. Jollie

Scanning Electron Microscopy

The free surface of the endodermal epithelial lining of the rat visceral yolk sac was examined by scanning electron microscopy at three stages of pregnancy, viz., 12, 17 and 22 days (birth typically occurring on the 23rd day). Additionally, by ultrasonic vibration of tissues that had been subjected to prolonged osmium fixation, the epithelium was removed and such microdissected membranes similarly were examined.

With increasing gestational age the free surface of the epithelium. underwent a relative increase in absorptive area by three mechanisms: formation of increasingly complex villous projections of the visceral yolk sac as a whole, a doming of …

Weighted Silks Observed Using Energy Dispersive X-Ray Spectrometry, M. Ballard, R. J. Koestler, N. Indictor

Scanning Electron Microscopy

A group of modern silk fabrics was treated with various weighting agents as standards. These standards were observed using energy dispersive x-ray spectrometry. The standards were compared to untreated samples and to museum specimens of weighted silks. In all prepared specimens the elements expected from treatment were observed; weighting treatments could be distinguished. The analytical procedures are discussed and compared to recent work on mordant analysis using the same techniques.

Elemental And Ultrastructural Characteristics Of The Egg Capsules Of Nautilus Pompilius, R. J. Koestler, E. D. Santoro, G. Dingerkus

Scanning Electron Microscopy

Six pearly nautili (Nautilus pompilius) raised in captivity produced nonviable egg capsules which were examined using scanning electron microscopy ( SE M) and energy dispersive x-ray spectrometry (EDS). Macro and microscopic observations revealed two distinct and separate walls encircling the yolk sac. Both walls exhibited a porous appearance in cross-section. Protein analysis demonstrated the proteinaceous nature of nidimental gland secretions and egg capsule walls.

EDS analysis of each wall shows the elemental composition to be identical in both, with each wall containing similar proportions of S, CI, Mg, Na, K, and trace amounts of Ca. X-ray mapping of Na and …

Application Of Scanning Electron Microscopy To The Study Of Shark Dermal Denticles, G. Dingerkus, R. J. Koestler

Scanning Electron Microscopy

Clear, high resolution scanning electron micrographs of shark dermal denticles are essential to allow the study of their morphology and micro-relief. Various techniques were tried to remove mucus and adventitious debris, including KOH, trypsin enzyme, and ultrasonication. In most species examined the best results were obtained with enzyme treatment followed by ultrasonication. For scanning electron microscopic examination it was found that 15 nm gold coating, or more, and 10 kV, or less, had to be employed to reduce charging of the denticles.

Urolithiasis In A Patient Ingesting Pure Silica: A Scanning Electron Microscopy Study, D. B. Leusmann, J. Pohl, G. Kleinhans

Scanning Electron Microscopy

A patient who repeatedly produced urinary calculi, had consumed about 3g of cristobalite (SiO₂) per day for many years. Investigations using scanning electron microscopy revealed minute particles containing silicon in the core of the stone as well as in urine sediment. A mechanism similar to that proposed for the effect of silicon-containing drugs against gastric ulcer, may play a role in this formation of silicon-containing urinary stones.

The Identification And Characterization Of Metal Wrappings In Historic Textiles Using Microscopy And Energy Dispersive X-Ray Spectrometry: Problems Associated With Identification And Characterization, N. Indictor, R. J. Koestler

Scanning Electron Microscopy

Scanning electron microscopy-energy dispersive x-ray spectrometry (SEM-EDS) has been employed for the description of metal wrapped yarns. Although considerable detail is obtainable as microphotographs, and elemental analysis is obtained with ease, caution should be exercised in interpreting results. Several unravelled samples should be examined; light microscopy should be employed prior to SEM-EDS analysis. Examination of eight specimens (six from the textile collection of the Metropolitan Museum of Art, New York; two from private collections) is described. The samples were Chinese (5), German (1), Spanish (1), Turkish (1). Difficulties encountered in describing this set of samples are enumerated.

Microtextures Of Laterites And Bauxites Capping Deccan Trap Basalts In Western India, D. V. Chitale, N. Güven

Scanning Electron Microscopy

Thirty-five samples of laterites and bauxites representing both the high-level (elevation > 1000 m) and low-level (elevation < 100 m) deposits in western India have been examined by scanning electron microscopy. Megascopically, laterites exhibit vesicular, spongy and pisolitic textures, whereas bauxites display pisolitic, massive and nodular textures. Laterites, as well as bauxites are commonly characterized by framework microtexture produced by a three dimensional arrangement of crystallites. Locally, the luterites and bauxites exhibit crystalline-webby microtexture formed by a web-like arrangement of stacks of lamellar crystals. The individual crystals in the matrix of laterites and bauxites display anhedral forms and they range in size from about 0.5 μm to 20 μm. Crystals larger than 20 μm in size generally occur as linings of the vugs, in channels and veins, and they are usually euhedral. Pisolites and nodules in laterites and bauxites are composed of material generally finer than the material in the matrix around them. Platy morphology is most common for the minerals in laterites and bauxites. Gibbsite occurs in various forms ranging from prismatic, stubby slab-like to lath-shaped crystals.

Both high-level and low-level deposits of laterites are characterized by similar textures. The variations in textures of bauxites are also found to be independent of the elevation of the deposits.

Embryonic Development Of The Chicken External Cloaca And Phallus, M. R. Bakst

Scanning Electron Microscopy

The use of the scanning electron microscope has provided new detailed information about the embryonic development of the chicken external cloaca and phallus and has consequently clarified the origin of the differences between the anatomy of the chicken and turkey phallus. At Day 6 (of incubation), the genital (g.) tubercle is formed in the ventral aspect of the embryo between the caudal fold of the amnion and the tail bud. On the ventral surface of the tail bud are paired g. swellings which flank the g. tubercle. Originating at the midline between the g. swellings is the g. crest which …