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The Use Of Scanning Electron Microscopy For Investigations Into The Three Dimensional Organisation Of The Interphase Nucleus, T. D. Allen, P. M. O'Connor

Scanning Microscopy

In an attempt to elucidate three dimensional information on the organisation of the nucleus, nuclei have been extracted from ascites tumour cells or tissue culture cells by a variety of biochemical techniques, and prepared for high resolution scanning electron microscopy using an osmium-thiocarbo-hydrazide infiltration procedure which has previously proved successful for analysis of chromosome structure. Nuclei were prefixed with either Methanol-Acetic acid, glutaraldehyde or formaldehyde and then extracted by a variety of detergents with the aim of a 'biochemical dissection' of their outer elements to allow surface visualisation of the nuclear lamina. Continued extraction removed all aspects of the nuclear …

Fine Structure And Organ Culture Of Chick Embryo Dorsal Aorta, C. Ward Kischer, Michael Jaqua

Scanning Microscopy

Embryonic blood vessels have not been grown in organ culture, in a way which might easily submit them to studies of vascular organogenesis. The chick embryo dorsal aorta is easily accessible and relatively simple to explant to culture. Its organ culture may provide a model for wounding and repair of the intima and/or media and provide a model for studies of growth (or maintenance) and differentiation. Fresh dorsal aorta and its organ culture from the chick embryo was characterized morphologically by light microscopy scanning (SEM) and transmission electron microscopy (TEM) from days 4 to 18. Explants were incubated up to …

Observations Of Colloidal Gold Labelled Platelet Microtubules: High Voltage Electron Microscopy And Low Voltage-High Resolution Scanning Electron Microscopy, R. M. Albrecht, J. Prudent, S. R. Simmons, J. Pawley, J. J. Choate

Scanning Microscopy

18 nm colloidal gold-antitubulin and 4 nm colloidal gold-antitubulin were used to label microtubules in adherent, fully spread platelets. Both sizes of marker effectively labelled microtubules in the partially extracted platelets. However only the 4 nm gold penetrated the dense microfilament matrix of the inner filamentous zone so that portions of microtubules within this cytoskeletal zone could be tracked. The gold marker could be visualized well with 1 MeV high voltage transmission EM and with 5 kV or greater secondary imaging or 20 kV backscattered imaging of carbon only coated samples. 1 kV secondary imaging permitted high resolution imaging of …

Survival Of Trout Strains As Affected By Limnological Parameters, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

Prior work at East Canyon Reservoir, Utah indicated that adult trout are important predators of stocked juvenile rainbow trout. Brown trout, in particular, were exclusively piscivorous when th~y exceeded 185 mm standard length. Fish became increasingly important in the diet of cutthroat trout greater than 330 mm. The purpose of this study was to further document the effect of adult trout on survival of juvenile rainbow trout in mid-elevation reservoirs. Causey Reservoir was chosen because it was thought to contain large brown and cutthroat trout and had not been intensively studied during the last eight years.

Effect Of Conidia Germination On Infection Of Brown Planthopper (Bph) By Insect Fungi, M. C. Rombach, R. M. Aguda, Donald W. Roberts

Biology Faculty Publications

Conidia of insect fungi actively invade BPH [brown planthopper]. After a conidium lands on the insect cuticle, germination takes about 8 to 16 h, depending on the temperature and relative humidity. After the germination, tuber is formed, the conidium produces specific chitinase enzymes to dissolve the insect cuticle. This allows the fungus to enter the insect body cavity, where further fungus growth occurs. At the end of the infection cycle, the mycelium sporulates on the outside of the insect. Conidia produced on the cadaver can infect healthy BPH initiating epizootics of the fungus. To test infection, 50 adult alate BPH …

The Radiomycetaceae (Mucorales; Zygomycetes). Calcium Oxalate Crystals On The Sporangiolar Wall And Aerial Hyphae, G. L. Benny, S. R. Khan

Scanning Microscopy

Calcium oxalate crystals occur on the sporangiolar appendages and aerial hyphae of the two known genera (Hesseltinella, Radiomyces) of the mucoralean family Radiomycetaceae. In Hesseltinella the sporangiolar appendages are acicular with a polygonal, square, or hexagonal, discoid base. The appendage core consists of calcium oxalate and is composed of two portions: (1) a round, acicular spine with a more or less hexagonal base, and (2) a square, polygonal, or hexagonal, discoid base with a central perforation that generally contains the spine base. Both portions of the spine core appear to be readily separable. In species of Radiomyces the …

Quantitative Margin Analysis In The Scanning Electron Microscope., J. F. Roulet, T. Reich, U. Blunck, M. Noack

Scanning Microscopy

Interface between restorative materials and tooth hard substances must be morphologically as perfect as possible to avoid plaque accumulation and subsequent secondary caries or pulpal diseases. Therefore the marginal behavior of restorations is an important parameter to predict their longevity.

Morphologically, the quality of margins is characterized by different well defined criteria. Using a replica technique it is possible to assess the complete marginal circumference of restorations in the SEM. Margins of restorations show a large variety of their morphology. This publication describes a method to quantify the quality of dental restorations.

The restoration margins are traced on the SEM …

Stimulation Of Collagen Formation In The Intestinal Anastomosis By Low Dose He-Ne Laser, David T. Yew, Winnie W. Y. Li, K. M. Pang, Y. C. Mok, C. Au

Scanning Microscopy

The effect of low dose He-Ne laser on the healing of intestinal anastomosis was studied in the albino rat. A small piece of jejunum was removed from each rat and the ends sutured back with a simple interrupted pattern. In the experimental animal, the anastomosis was Irradiated through an optic fiber with a He-Ne laser (1 mW) for 15 minutes whereas in the control animal, the anastomosis was not irradiated. The differences between the two groups were compared by histology, transmission electron microscopy, scanning electron microscopy and autoradiography 3 and 7 days after operation. The laser treated experimental animals demonstrated …

Complementary Surface Characterization Of Chalcopyrite By Electron Microscopy, Electron Spectroscopy, And Optical Reflectance, P. H. Ruzakowski, P. H. Holloway, G. Remond

Scanning Microscopy

Surface oxidation of polished natural specimens of chalcopyrite (CuFeS₂) at temperature between 23°C and 300°C in air has been characterized by Auger electron and X-ray photoelectron spectroscopies. The reaction products consisted of an outer iron oxide layer and an intermediate copper rich sulfide layer. Several different oxides and sulfides were consistent with the electron spectroscopy data, so specimens were analyzed as a function of time and temperature at selected 20 μm diameter areas with an optical microreflectometer (OMR). Since the optical properties of a compound are unique, a reflectance model with three homogeneous layers was used to calculate …

Optical Design Considerations In Confocal Scanning Microscopy, T. Wilson

Scanning Microscopy

We review the properties and applications of confocal optical systems. We concentrate on non-fluorescent reflection systems and on applications which make use of the unique optical sectioning property of these instruments to provide three-dimensional images. A crucial design choice concerns the form and size of the detector. We therefore concentrate on the role of the detector size on the strength of the optical sectioning. We find that although the sectioning becomes weaker as the detector sizes where the sectioning remains essentially constant. We also consider the role of lens aberrations which are inevitably present and find, inter alia, that these …

Visualization And Analysis Techniques For Three Dimensional Information Acquired By Confocal Microscopy, G. J. Brakenhoff, H. T. M. Van Der Voort, M. W. Baarslag, B. Mans, J. L. Oud, R. Zwart, R. Van Driel

Scanning Microscopy

Confocal Scanning Laser Microscopy (CSLM) is particularly well suited for the acquisition of 3-dimensional data of microscopic objects. In the CSLM a specific volume in the object is sampled during the imaging process and the result is stored in a digital computer as a three-dimensional memory array. Optimal use of these data requires both the development of effective visual representations as well as analysis methods. In addition to the well known stereoscopic representation method a number of alternatives for various purposes are presented. When rendering in terms of solid-looking or semitransparent objects is required, an algorithm based on a simulated …

Quantitative Electron Microprobe Analysis Of Cryosections, Albert J. Saubermann

Scanning Microscopy

There are numerous approaches to preparation and analysis of biological specimens which have been developed in many laboratories involving the use of cryosections. Because there is no clear consensus on how such samples should be produce or analyzed, it can be a formidable problem to choose or even review possible options. Therefore, it is the purpose of this tutorial to consider, in an instructional manner the problems of specimen preparation and analysis in terms of the solutions and procedures used by the author. The discussion, consequently. focuses on the problems of specimen preparation and analysis as seen by the author. …

Ion Microscopy: A New Approach For Subcellular Localization Of Labelled Molecules, E. Hindie, P. Hallégot, J. M. Chabala, N. A. Thorne, B. Coulomb, R. Levi-Setti, P. Galle

Scanning Microscopy

Secondary ion mass spectroscopy (SIMS) was used to obtain images representing the intracellular distribution of molecules labelled with carbon 14.

Deoxyadenosine labelled with carbon 14 was added to a cultured human fibroblast cell medium, and the intracellular distribution of this molecule was studied using three different SIMS instruments: the CAMECA IMS 3F and SMI 300 ion microscopes and the UC-HRL scanning ion microprobe.

Carbon 14 distribution images obtained by this method show that deoxyadenosine U-C14 is present in the cytoplasm as well as the nucleus, with a higher concentration in' the nucleoli. Our study clearly demonstrates that ion microscopy is …

Tubuloreticular Reorganization Of Cytomembranes In Cells Treated With With Human Alpha Interferons - A Review, P. M. Grimley, S. Ray, M. Kostianovsky, B. Rupp, Y. -H. Kang, D. Feldman

Scanning Microscopy

Human alpha interferons (IFN-a) cause a reorganization of internal cell membranes into tubuloreticular inclusions (TRI). Morphogenesis and cytochemistry indicate a pre-Golgi intracisternal origin from the endoplasmic reticulum. Clinically, TRI formation in human blood mononuclear cells correlates with systemic IFN-a treatment or with endogenous overproduction of IFN-a in viral or autoimmune diseases (e.g., rubella syndrome, AIDS, systemic lupus erythematosus). In vitro, TRI formation can be produced by treatment of Daudi lymphoblasts or vascular endothelial cells with IFN-a, and is blocked by actinomycin-D. In Daudi lymphoblasts or vascular endothelial cell cultures, TRI formation parallels induction of 2'-5' A synthetase, inhibition of …

Attachment Of Plasma Membranes Of Cultured Cells To Silicon Chips For High Magnification Imaging In Scanning Electron Microscopy, Klaus-Ruediger Peters, William W. Carley

Scanning Microscopy

In the membrane preparation method described in this paper, a polylysine-coated silicon chip is adsorbed to the exposed apical surface of a cell monolayer. Upon removal, the adsorbed chip separates the plasmalemma from the residual bodies of the cultured cells. This sandwich-membrane separation approach simplifies access to the cytoplasmic aspects of both the apical and the basal plasmalemma which remains on the culture substrate and is covered to a varied extent by cytoplasmic infrastructures. To stabilize the attached membranes, small crosslinking agents are used in a controlled osmium impregnation. Large crosslinkers are avoided since they induce thickening of fine structures. …

A Rapid Method For Observing The Internal Morphology Of Amphibian Embryos, S. C. Smith, J. B. Armstrong, D. C. Hoppe

Scanning Microscopy

A simple, rapid method for visualizing the internal morphology of amphibian embryos is described. Fixed embryos of Ambystoma mexicanum are surrounded with commercial embedding material and are frozen. Internal structure is revealed by cutting the embryos with a cooled scalpel or razor blade, removing the frozen embedment with an aqueous buffer, and processing the halved embryos for scanning electron microscopy (SEM). This technique allows the internal anatomy of the embryo to be viewed but is much simpler and more rapid than previously described techniques. It should therefore prove useful for understanding and teaching the three-dimensional relationship between tissues in developing …

A New Versatile Holder For The Calibrating Standard Used For Quantitative Analysis In Jeol 840 Sem, Michael Dvorachek

Scanning Microscopy

An improved holder has been designed for a cobalt calibrating standard used in an EDS Link 10,000 system attached to a JEOL 840 SEM. This holder allows the calibration of the EDS software for a wide range of samples differing in size, surface and height. These differences usually cause difficulties during quantitative analyses. The new holder allows the position of the cobalt to be adjusted according to the size and height of the sample.

Dynamic Analyses Of Lymphoblast Membranes Exposed To Alpha Interferon Using Flow Cytometry And Fluorescence Recovery After Photobleaching, E. Balint, A. Aszalos, P. S. Pine, P. M. Grimley

Scanning Microscopy

Interferons represent a major group of the biologic response modifiers which exert multipotent effects upon cell growth, cytodifferentiation and immune functions. Previous experimental studies with alpha interferon (IFN-𝝰) have suggested that modulation of transmembrane signaling could be a critical determinant in the bioregulatory diversity. To determine whether any initial changes at the plasma membrane would directly correlate with one or more actions of IFN-𝝰, we investigated cultures of Daudi lymphoblasts which are uniquely susceptible to growth inhibition. Complementary biophysical techniques were applied. In one approach, changes in plasma membrane ion flux were measured by flow cytometry, using a fluorescent dye …

Vascularization Of Male Gonads In Blennius Pavo (Teleostei, Blenniidae) As Revealed By Scanning Electron Microscopy Of Vascular Corrosion Casts, F. Lahnsteiner, A. Lametschwandtner, R. A. Patzner, H. Adam

Scanning Microscopy

The vascular architecture of male gonads of Blennius pavo is studied by scanning electron microscopy of vascular corrosion casts. Arterial supply to the gonads is by a branch of the first ventral segmental artery of the tail. From the surface of the gonads, this vessel gives rise to branches which supply testes, spermatic ducts, testicular glands, blind pouches, urogenital sinus and urogenital papilla. The testis has a rope-ladder-like capillary network around the seminiferous tubules, while in the testicular gland the capillary network is irregular in form. The spermatic ducts are found to have an exterior capillary network located in the …

Utah Science Vol. 49 No. 3, Fall 1988

Utah Science

58 COLOR DEFECTS OF FRESH AND COOKED MEAT D. Cornforth Fresh meat is supposed to be bright cherry red, and cooked meat isn't A food scientist explains how the opposite. occurs occasionally.

66 MINIMIZING BROWSING DAMAGE BY DEER: LANDSCAPE PLANNING FOR WILDUFE D. D. Austin and A. B. Hash A little bit of planning can make life a lot easier for deer as well as homeowners ..

71 THE U.S. LIVING COLLECTION OF PERENNIAL TRITICEAE GRASSES D. R. Dewey The Triticeae grasses have several attributes of immeasurable value if incorporated in other species. The IS-acre collection near Logan is helping …

Investigation Of Surfaces And Interfaces By Electron Optical Methods, H. Seiler

Scanning Microscopy

The combination of methods for surface analysis with electron microscopes (EM) gives the possibility for surface and interface microanalysis. The paper deals with different methods a) for imaging of surfaces with high lateral resolution: Emission EM (EEM), Scanning EM (SEM), Reflection EM (REM) Transmission EM (TEM) using special preparation methods as replica techniques or cross section specimens b) for crystal structure investigation: Low and High Energy Electron Diffraction and Electron Chanelling Patterns and c) for material analysis using electron spectroscopy either of the emitted or scattered electrons.

The combination of all analytical methods in one instrument for surface microanalysis (SMA) …

Concentrations Of Elements In Dying Thymocytes From The Thymus Gland Of Diabetic Rats, Alice Warley, I. W. Morris

Scanning Microscopy

Atrophy of the thymus gland occurs in rats made diabetic by a single injection of the drug streptozotocin. Histological studies show the presence of thymocytes with pyknotic nuclei in thymus tissue taken from diabetic animals. Analysis of the elemental content of the pyknotic cells was carried out on freeze dried frozen sections of thymus tissue using the technique of X-ray microanalysis. There was no loss of elements from cells which had undergone the early morphological changes characteristic of pyknosis and which showed the condensed chromatin of pyknotic nuclei. However as the cells shrank and lost the clear distinction between nucleus …

Ariane Utilization For Secondary Payloads, G.G. Reibaldi, M. Trischberger, G. Melchior, J. Breton

Small Satellite Conference

In preparing for the future, the European Space Agency (ESA) has identified a growing shortage of flight opportunities for secondary payloads. This was most directly felt in the execution of the In-Orbit Technology Demonstration Programme (TOP), which is aimed at the demonstration of new technologies in orbit, before their application in projects, thereby reducing the overall risk. The TOP took a lead in investigating the possibility of using the European heavy lift launcher Ariane-IV as a low cost secondary payload carrier, not only for technological, but also for scientific and educational experiments. The secondary payloads were in the form of …

The Scout Launch Vehicle System, Pamela Tanck, James Williams

Small Satellite Conference

SCOUT, a four-stage, solid-rocket launch vehicle originally developed by LTV Missiles and Electronics Group, is completing its third decade of service. NASA-Langley started the program in 1958 with the intent of providing a simple, low-cost, reliable launch vehicle for orbital, probe and re-entry missions. On July 1, 1960, the first SCOUT vehicle was launched. Since SCOUT became operational in 1963, there have been 88 launches of which 84 were successful, representing a reliability record of 95.5 percent successful flights. In addition, over the past 20 years the reliability rate is an excellent 98.2 percent. The role of the SCOUT launch …

X-Ray Analysis Of Biological Fluids: An Update, G. A. Quamme

Scanning Microscopy

X-ray analysis has been used for some twenty years to quantify elements including Na, K, Cl, Ca, Mg and phosphorous in biological fluid samples. The method consists of accurate pipetting of 50-150 pl samples and appropriate drying to form crystalline deposits. Quantitation is obtained by comparison of x-ray intensities with comparable standard crystalline deposits. Electon microprobe analyses have contributed much to our understanding of renal transport function including physiological controls and pathological influences on the tubular handling of the major elements. New approaches to x-ray analysis of solid tissue will further our knowledge concerning transport properties in the kidney and …

Surface Visualisation Of Tissue Interfaces By Scanning Electron Microscopy. Methods For Exposure Of The Basal Lamina And Associated Structures In Human Amnion, T. D. Allen, J. D. Aplin, S. Campbell

Scanning Microscopy

Tissue interfaces such as basal lamina have been traditionally investigated in transmission electron microscopy by sections cut vertical to the lamina, presenting information restricted to a single ultrathin plane. In order to overcome this limitation, a methodology for surface visualisation of the underside cell membranes of the amniotic epithelium, the upper and lower basal lamina surfaces, and their relationship to the stromal collagen has been devised. This involves alkaline, detergent or enzymatic loosening and/or removal of the epithelial monolayer prior to fixation, followed by dry fracture after critical point drying. In this way we have visualised large areas of all …

Contrast And Resolution Of Secondary Electron Images In A Scanning Transmission Electron Microscope, J. Liu, J. M. Cowley

Scanning Microscopy

Recent advances in the improvement of secondary electron image resolution to the subnanometer level demand further knowledge of the origin of secondary electron emission to interpret the experimental results. The generally accepted estimation of the non-localized range of the inelastic scattering of incident electrons and the subsequent generation of secondary electrons in a solid cannot explain the 0.7 nm resolution of secondary electron images obtained in a scanning transmission electron microscope operated at 100 kV. Resolution and contrast of secondary electron images are interrelated. High contrast as well as high resolution can be obtained at the same time. Contrast mechanisms …

Determination Of Fiber Content In Long Fiber Reinforced Composites By Scanning Electron Microscopy And Image Analysis, R. F. Antrim

Scanning Microscopy

Currently, there is a wide interest in further developing long fiber reinforced composites. Due to the dependence of a material's mechanical properties to its microstructure, further development of microanalytical techniques is needed to quantify the amount of fiber. In response, a standardless technique was developed to determine the volumetric fiber content and its variation in an oriented long fiber reinforced composite. The method utilizes scanning electron microscopy to acquire backscattered electron images of polished cross-sections. The images are then processed to determine the fiber area fraction which, in this particular case, is equal to the volume fraction. The results presented …

Scanning Electron Microscope, Freeze Etching And Glycosaminoglycan Cytochemical Studies Of The Cerebellar Climbing Fiber System, Orlando J. Castejón, Haydée V. Castejón

Scanning Microscopy

Mouse and teleost fish cerebelli were processed by the freeze-fracture methods for scanning and transmission electron microscopy in order to study the three-dimensional morphology and intramembrane features of climbing fiber-Purkinje spine synapses. In addition, Alcian Blue and ruthenium chloride stainings were applied to mouse cerebellar tissue to investigate the polyanion composition of these excitatory synapses under the transmission electron microscope. In the granular layer, tendril and glomerular collaterals of climbing fibers were observed. In the molecular layer climbing fibers exhibited a characteristic crossing-over or arborescence pattern type of bifurcation, Scheibel's collaterals and multiple thorn synapses with Purkinje spiny dendrites. At …

Lymphoid Microenvironments In The Thymus And Lymph Node, W. Van Ewijk, P. J. M. Brekelmans, R. Jacobs, E. Wisse

Scanning Microscopy

The three-dimensional architecture of the thymus and mesenteric lymph node reveals several different stromal cell types important in the development and function of T cells. In the thymic cortex, T cells proliferate and differentiate in a meshwork of epithelial-reticular cells. They then migrate towards the medulla where they may interact with interdigitating cells. T cells migrate from the thymus through perivascular spaces, surrounding large vessels at the cortico-medullary boundary. In this area also large thymic cystic cavities are found, their function remains at present unclear. Mature "selected" T cells leave the thymus most probably by the venous bloodstream, to enter …