bluuebunny/crossref_metadata_2025 huggingface dataset:
Unusual Microstructure in Shock-Compacted Graphite
Authors: Trueb Lucien F.
Published: June 2020

Crushed and statically compressed Madagascar graphite that was explosively shocked at 425 kb by means of a planar flyer-plate is characterized by a black zone extending for 2 to 3 nun below the impact plane of the driver. Beyond this point, the material assumes the normal gray color of graphite. The thickness of the black zone is identical with the distance taken by the relaxation wave to overtake the compression wave.

The main mechanical characteristic of the black material is its great hardness; steel scalpels and razor blades are readily blunted during attempts to cut it. An average microhardness value of 95-3 DPHN was obtained with a 10 kg load. This figure is a minimum because the indentations were usually cracked; 14.8 DPHN was measured in the gray zone.
Preparation of Thin Sections using a Fracture-Extraction Technique
Authors: Emma Thomas A.
Published: June 2020

The preparation of thin sections for transmission electron microscopy by chemical or electrolytic thinning is time consuming and can introduce contamination. This is a serious problem when inclusions and precipitates in single crystals are being identified. A technique which reduces the likelihood of contamination and has the additional advantage that specimens can be prepared rapidly uses a fracture process followed by physical extraction. The method is also useful for studying defects generated at a fracture plane.

The technique is a modification of a method reported previously for preparing thin glass sections. The specimen is fractured in a dry, inert atmosphere such as nitrogen or argon. The fracture surface usually contains fragments that have the proper shape and thickness to serve as thin sections.
Growth and Structure of Germanium Films Evaporated Onto Rock Salt
Authors: Shimaoka G. , Chang S. C.
Published: June 2020

Recent studies of evaporated germanium films have demonstrated that their structure and epitaxy are greatly influenced by various evaporation parameters such as vacuum pressure, substrate surface conditions, and deposition rate as veil as substrate temperature. The purpose of this study is to investigate growth and structure of germanium thin films evaporated onto a clean rock-salt substrate in ultrahlgh vacuum and to find optimum epitaxial growth condition.

High-purity (intrinsic) germanium was evaporated at various deposition rates, 0.1-5Å/sec, and thicknesses, 3O-5OOÅ, onto vacuum-cleaved and air-cleaved (001)NaCl substrates held at 25°-500°C in a vacuum of ∼10-8Torr. Some films were prepared under lateral electric field of dc 100V/cm or an electron-beam irradiation with ∼1015 electrons/cm2/sec, 300-400V, applied to the substrate during evaporation.
High Resolution Specimen Area Imaged Under Negligible Field Aberrations
Authors: Yanaka T. , Shirota K.
Published: June 2020

It is significant to note field aberrations (chromatic field aberration, coma, astigmatism and blurring due to curvature of field, defined by Glaser's aberration theory relative to the Blenden Freien System) of the objective lens in connection with the following three points of view; field aberrations increase as the resolution of the axial point improves by increasing the lens excitation (k2) and decreasing the half width value (d) of the axial lens field distribution; when one or all of the imaging lenses have axial imperfections such as beam deflection in image space by the asymmetrical magnetic leakage flux, the apparent axial point has field aberrations which prevent the theoretical resolution limit from being obtained.
Void Coarsening During Irradiation of Stainless Steel
Authors: Laidler J.J. , Mastel B.
Published: June 2020

It is of interest in fast breeder reactor design to know whether saturation of void-related swelling in stainless steel occurs at high neutron fluences. One factor which may preclude saturation is a coarsening of the void structure, which would essentially reduce the rate of decrease of intervoid spacing. The HEDL JEM-1000 electron microscope was used to produce very high equivalent neutron fluences by irradiating an annealed Type 316 stainless steel specimen with 1 MeV electrons at 600°C; stereomicrographs made at regular fluence increments were used to determine the nature and extent of void coarsening reactions. The specimen did not contain helium, so the void distribution is inherently more coarse (larger mean void size, lower void concentration) than would be the case for neutron irradiation.
Optimum Stereo Tilt Facilities on the AEI Mk II High Voltage Electron Microscope
Authors: Beeston B.E.P.
Published: June 2020

Stereo-imaging is essential to the full utilization of the increased specimen penetration available in the high voltage microscope. Biological specimens 0.25–5 μm thick, depending upon the density and specificity of staining, and metals and materials 0.1–7 μm thick, depending upon their density can be penetrated at adequate resolution at 1000-1200 kV. However, the considerable amount of overlapping detail observed in such specimens makes stereo-imaging essential for the full elucidation of the internal structure. In order that the final stereo pair of micrographs may be readily ‘fused’ by the observer to reveal optimum specimen ‘depth’, a number of requirements should be met:

1) The stereo tilt axis should be vertical when the two prints are laid side-by-side on the stereo viewer. This requirement is always met in the EM7 Mk II as the microscope incorporates a non-rotational imaging system for magnifications 4,000–1,000,000 X. By balancing the individual image rotations of the four imaging lenses against one another, a total rotation of zero between the specimen and the image is maintained. Now by tilting the specimen in the ±45° front-loading side-entry tilt rod, the image always ‘tilts’ about a vertical axis on the viewing screen, parallel to the long edge of a 6×9 cm sheet in the film camera.

2) The magnification of the two micrographs should be as similar as possible.

3) The two micrographs should be in as closely similar an orientation as possible.

4) The focus of the two micrographs should be as similar as possible. (The deviations in 2), 3) and 4) which can be accepted have been discussed in detail by Willis and Julesz).
A New Fine-Structure Observed in Electron-Diffraction Rings
Authors: Corbett J. M. , Fairchild J. , Boswell F. W.
Published: June 2020

Fine-structure in spotty electron diffraction riiig patterns has previously been observed for specimens made up of MgO smoke particles of cubic morphology. This fine-structure was shown to arise from refraction effects in the small cubes (Sturkey & Frevel). We have recently observed a different type of fine structure in patterns from MgO films prepared by vacuum deposition (Fig. 1). This fine-structure consists of sets of regularly spaced fringes occurring at random orientations in the rings. The fringes may be seen in Fig. 2 which shows a segment of the (200) ring magnified 7x from the pattern in Fig. 1. It was considered possible that each set of fringes might arise from two superimposed diffraction’ spots from suitably situated crystallites in the specimen. Experiments have been conducted which clearly demonstrate that the fringes do in fact arise in this way.
Solubility Studies of Flame Retardant Cotton-Polyester Fabric Blends
Authors: Boylston E. K. , Muller L. L. , Goynes W. R. , Babin R. M.
Published: June 2020

Because of increasing public awareness and strong legislative regulations, the production of nonflammable textile fabrics is essential. Generally, phosphorous-nitrogen polymers are very effective fire retardants, especially when applied to cotton fibers. Since many fabrics marketed today are blends of cotton and synthetic fibers, flame retardants that are compatible with these blends must be developed.

Preliminary research on blended cotton-polyester fabrics treated with a mixture of tetrakishydroxyethylphosphonium chloride (THPC) urea, trimethylolmethylglycoluril (TMMGU), and polyvinylbromide (PVBr) has produced a flame retardant finish that is durable through 60 laundry cycles. This mixed emulsion was padded onto the fabric, dried, and heat cured to polymerize in situ on the surface and within the fibers. The polyvinylbromide was added because bromine compounds are known flame retardants and polyester has an affinity for polyvinylbromide.
A New Multiple Specimen Table for Freeze-Etching
Authors: Paik S. K. , Allen J. R.
Published: June 2020

Considerable progress in freeze etching technique has been made during the last ten years. The purpose of this technique is the preparation of replicas for electron microscopy. The technique consists of four steps. After (a) freeze-fixation, (b) the specimen surface is fractured with a cooled microtome knife in the vacuum chamber, (c) etched by low temperature sublimation, and (d) a replica of the etched surface is produced by evaporation of platinum and carbon.

The electron microscopic image obtained with a freeze-etched replica is highly dependent upon the quality of the replìcas. This quality is very easily affected by the thickness of the evaporated layer and the angle of shadowing.
A Detailed Exploration of the Axial Magnetic Field Distribution Within Lens Pole Pieces
Authors: Engler P. E.
Published: June 2020

Contrast and resolution are the most crucial parameters in biological electron microscopy. These parameters are sensitive functions of spherical aberration and astigmatism. Axial astigmatism is produced by a rotational asymmetry in the axial magnetic field distribution Bz (r, ) in the objective pole piece, and is adjusted with a stigmator that locally compensates for the rotation asymmetry. Spherical aberration is frequently determined from a measurement of the on-axis field distribution only; it is presupposed that the axial field distribution is rotationally symmetric and that the pole piece axes are coliniar straight lines.

Commercial probes used to measure axial magnetic fields in conventional electron microscope pole pieces are so large that off-axis fields cannot be measured, and consequently the degree of rotational symmetry cannot be assessed.
An Experimental System Combining Medium Energy Electron Diffraction and Scanning Electron Microscopy
Authors: Cowley J.M. , Koch F.A. , Albain J.L.
Published: June 2020

The theoretical and experimental advantages of using medium energy electrons (1-10 keV) instead of LEED and RHEED methods for quantitative surface studies were discussed by Moon and Cowley. A highly versatile ultra high vacuum system that exploits some of these advantages was constructed in our laboratory. The purpose of this paper is to describe design details of the instrument and to present initial data obtained.

An overall view of the jinstrument is shown in Fig. 1. A commercially available field emission gun was attached to a Varian 240 LEED chamber. The pumping system is oil free and consists of cryosorbtion and Vaclon pumps.
Transformation of Upton, Wyoming Bentonite into Illite in Artificial Sea Water
Authors: McKee T. R. , Whitehouse U. G.
Published: June 2020

Diagenetic formation of illitic clay minerals from montmorillonitic clay minerals has often been inferred in order to explain the observed distribution and occurrence of clay minerals in the world ocean and sediment column. Whitehouse and McCarter reported laboratory experiments which showed some evidence that an illitic component had formed from a pure, well characterized montmorillonitic source material after exposure to artificial sea water for periods of up to five years. The present report consists of the cha racterization by transmission electron microscopy and electron diffraction of the illitic portion present after twenty years of exposure to artificial sea water. A more extensive and complete characterization of the other fractions and total material is in preparation.
Sad Properties of Micas and Montmorillonites
Authors: Güven Necip
Published: June 2020

Micas, whose structures are well known from x-ray and neutron diffraction studies, may help us to understand the properties of SAD patterns from fine grained clay minerals such as montmorillonites. The reciprocal lattice plane (a*c*) of a mica is shown in Fig. 1A. The c*-direction is taken parallel to the electron beam and the Ewald sphere is considered to coincide with the a-b plane of the mica in the vicinity of the origin. It can be shown that the height (∆p) of a reciprocal lattice point above the a-b plane is given by the relationship: ∆p = (h/3).c* + ℓ*. This tells us that the recripocal lattice points exactly intersecting the Ewald sphere have h indices with h = 3n or zero. The shape effects of thin micas cause elongation (∆u) of the reciprocal lattice spots, whose amount is given by ∆u = 2/nd, where d is the thickness (10Å) of elementary mica layers. The extent to which the reciprocal lattice point intersects the Ewald sphere and, hence, the intensity of the spots, depend on the number of the layers and on the height (∆p) of the reciprocal lattice points. Thus, the relative intensities of SAD spots from thin micas may vary in an unpredictable ·manner.
An SEM Study of Microfabrics from the Irish Chalk
Authors: Pierce Robert W. , Harper Howard E.
Published: June 2020

Sediment compaction and subsequent cementation must be considered important mechanisms for the reduction of porosity in the fine grained rocks studied. Evidence for early post-depositional compaction includes micrite grain flow around large bioclasts and grain orientation. Fracture of delicate grains causing some displacement was observed with suturing or serration at the grain boundaries between broken fragments of microfossils. Styolites cutting through grains and matrix suggests continued compaction. Geopetal structures and veins with incorporated whole microfossils indicate some grain support from partial cementation. Micrite veins with crystal orientation parallel to the trend of the vein may represent anastomosis tubes for the dewatering of the sediment.
Scanning Electron and Light Microscope Observations of Ostracodes
Authors: McRaney John K.
Published: June 2020

Muscle-scar pattern, pore canals, hinge characters, and structures and ornamentation of the carapace are important features in classifying members of the crustacean subclass Ostracoda (Latreille, 1806), an important fossil group for biostratigraphers and paleoecologists. The present terminology and taxonomy of ostracodes is based on optical microscopy. Scanning electron and optical microscope examinations of the above morphological characters on several genera of Holocene ostracodes(.4-2 mm. in size) of the Mississippi River mudlumps were made to compare the resolution capabilities of the two systems when studying ostracodes. The specimens were first observed in reflected light, then immersed in glycerine (which makes the calcite carapace translucent) for examination in transmitted light. The ostracodes were then cleaned, coated with a gold thin film, and examined with the SEM.
Modular Magnetic Lens Accessory to Basic Field Emission SEM
Authors: Holmes Duane C. , Cooper James H. , Gold James J. , Welter L. M.
Published: June 2020

It is well known that field emission produces a significantly brighter probe than conventional heated-filament methods. Heretofore, however, the only commercially available field emission SEM exploited this brightness advantage to permit TV rate scanning at all magnifications; the viewing of large, bright, “flicker free” and “stripe-free” images; and lownoise photography at short exposure times. A resolution of 250 Å, in secondary mode, was obtained using an electrostatic lens design. The high brightness may also be exploited to yield very high resolution and/or high signal to noise images.
Elastic Scattering in Electron Microscopy
Authors: Langmore J. , Isaacson M. , Wall J. , Crewe A. V.
Published: June 2020

High resolution dark field microscopy is becoming an important tool for the investigation of unstained and specifically stained biological molecules. Of primary consideration to the microscopist is the interpretation of image Intensities and the effects of radiation damage to the specimen. Ignoring inelastic scattering, the image intensity is directly related to the collected elastic scattering cross section, σɳ, which is the product of the total elastic cross section, σ and the eficiency of the microscope system at imaging these electrons, η. The number of potentially bond damaging events resulting from the beam exposure required to reduce the effect of quantum noise in the image to a given level is proportional to 1/η. We wish to compare η in three dark field systems.
Computer Fourier Analysis of Electron Micrographs From Caulobacter Crescentus Bacteriophage ϕCbK.
Authors: Lake James A. , Leonard Kevin R.
Published: June 2020

The capsid, or head, of C. crescentus phage ϕCbK is a prolate cylindrical structure, about 2000A in length and 600A in diameter, closed off at each end by pyrimidal caps (Agabian-Keshisian and Shapiro, 1970). During preparation for electron microscopy, the capsid can be broken at one or both ends and the DNA released, with the result that the empty capsid collapses evenly to form a bilayered protein sheet. Electron micrographs of negatively stained empty capsids (Fig. 1) give clear optical diffraction patterns with resolution of periodic detail extending to about 25A in reciprocal space (Fig. 2). Thus, for the first time, it is possible to establish quantitatively the capsid topology of a bacteriophage. In earlier studies of this bacteriophage, (Leonard et al., 1972) these images and their diffraction patterns were interpreted as tentatively showing five-fold rotational symmetry for the capsid about the cylinder axis.
To What Extent are Inelastically Scattered Electrons Useful in the Stem?
Authors: Rose H.
Published: June 2020

The scanning transmission electron microscope offers the possibility of utilizing inelastically scattered electrons. Use of these electrons in addition to the elastically scattered electrons should reduce the scanning time (dose) Which is necessary to keep the quantum noise below a certain level. Hence it should lower the radiation damage. For high resolution, Where the collection efficiency of elastically scattered electrons is small, the use of Inelastically scattered electrons should become more and more favorable because they can all be detected by means of a spectrometer. Unfortunately, the Inelastic scattering Is a non-localized interaction due to the electron-electron correlation, occurring predominantly at the circumference of the atomic electron cloud.
Energy Filtration of Electron Microscope Images
Authors: Henkelman R.M. , Ottensmeyer F.P.
Published: June 2020

Chromatic aberration and lack of contrast are two of the main obstacles to high resolution biological microscopy. Dark field microscopy has been shown to alleviate the contrast problem for biological macromolecules and even for the visualization of atoms. However for the normal range of biological specimens (i.e. viruses, thin sections, etc.) while dark field still provides good contrast, the image quality is so badly degraded by the increased fraction of inelastic electrons used that the image is of little or no value. Even in bright field the small contrast available is degraded by chromatic aberrations. An energy filter which does not depend on scanning of the image and which gives good energy resolution while maintaining the spatial resolution of the microscope would be useful.
Determination of the Characteristics of a Field Emission Source by Geometrical and Wave Optical Methods
Authors: Kuo Huei Pei , Siegel Benjamin M.
Published: June 2020

The radius of the image figure of a field emission source is determined by the aberrations of the total electron optical system and is usually given by adding the individual aberration and image figures in quardrature where rO is the intrinsic source radius, rs and rc are the radius of aberration figures given by spherical and chromatic aberration respectively, and rd is the radius given by diffraction, all referred to object space. Different authors have used different image planes and ambiguity has been introduced. The plafie with the minimum image figure (optimum plane) should be used and can be determined by geometrical methods only when diffraction effects are negligible; otherwise, a wave optical treatment should be used.
Single Particle Analysis
Authors: McCrone Walter C.
Published: June 2020

All of us are familiar with dust, dirt and smoke particles in the atmosphere. Many of us, in industry, are also familiar with contamination of our products, often by these same atmospheric pollutants. In any program to clean up the atmosphere or to clean up a given industrial product it is helpful, to say the least, to know the chemical composition and source of the contaminant particles. During recent years many new physical analytical techniques have been developed which can be applied to the identification of single small particles as small as a picogram (about 1 μm in diameter); most of these new methods involve electron optics, e.g., electron microscope and electron microprobe.
Selection and Preparation of Specific Tissue Regions For Tem Using Large Epoxy-Embedded Blocks
Authors: Lowrie P. M. , Tyler W. S.
Published: June 2020

The importance of examining stained 1 to 2μ plastic sections by light microscopy has long been recognized, both for increased definition of many histologic features and for selection of specimen samples to be used in ultrastructural studies. Selection of specimens with specific orien ation relative to anatomical structures becomes of critical importance in ultrastructural investigations of organs such as the lung. The uantity of blocks necessary to locate special areas of interest by random sampling is large, however, and the method is lacking in precision. Several methods have been described for selection of specific areas for electron microscopy using light microscopic evaluation of paraffin, epoxy-infiltrated, or epoxy-embedded large blocks from which thick sections were cut. Selected areas from these thick sections were subsequently removed and re-embedded or attached to blank precasted blocks and resectioned for transmission electron microscopy (TEM).
Densitometric Identification of Primitive Erythroblasts After Reaction With Diaminobenzidine
Authors: Trotter John A.
Published: June 2020

Hemoglobin is the specific protein of red blood cells. Those cells in which hemoglobin synthesis is initiated are the earliest cells that can presently be considered to be committed to erythropoiesis. In order to identify such early cells electron microscopically, we have made use of the peroxidatic activity of hemoglobin by reacting the marrow of erythropoietically stimulated guinea pigs with diaminobenzidine (DAB). The reaction product appeared as a diffuse and amorphous electron opacity throughout the cytoplasm of reactive cells. The detection of small density increases of such a diffuse nature required an analytical method more sensitive and reliable than the visual examination of micrographs. A procedure was therefore devised for the evaluation of micrographs (negatives) with a densitometer (Weston Photographic Analyzer).
Ultrahistochemical Studies of Mucosubstances : Electron Microscope Observation and Microprobe Analysis of the Chick Embryo Cornea
Authors: Ohkura T. , Iwatsuki H. , Watanabe T.
Published: June 2020

As described in a previous report, Alcian blue provides the selective contrast enhancement of interfibrillar substances of the mesostroma of the chick embryo cornea. This finding was also verified by the electron probe microanalysis of adjacent sections. In the present study the nature of interfibrillar substances was ultrahistochemically examined by a modified Seligman's method for the demonstration of some oxidizable glycols.

Strips of the 4th day chick embryo.cornea were fixed in ice-cold 2.5% glutaraldehyde solution (pH 7.4). Tissue specimens treated with 1% aqueous periodic acid or 0.2% hyaluronidase solution of pH 6.0 for 15 min were transferred into 1% thiocarbohydrazide, followed by a rinse in 1% osmium tetroxide solution (60°C, 50 min).
Fine Structural and Biochemical Investigations on the Effects of High Calcium Prepartal Diets on Homeostatic Mechanisms in Thyroid Glands, Bone, and Intestine Of Cows
Authors: Black H. E. , Capen C. C. , Yarrington J. T. , Rowland G. N.
Published: June 2020

Parturient paresis of dairy cows is a metabolic disease characterized by the development of severe hypocalcemia and hypophosphatemia near parturition in the presence of high circulating levels of parathyroid hormone. High calcium (CA) diets have been incriminated in increasing the incidence of the disease. The objective of this investigation was to determine the long-term effects of feeding a high CA (150 gm CA and 25 gm P/day) prepartal diet on the ultrastructure and function of thyroid parafollicular (C-) cells and duodenal absorptive and goblet cells of pregnant cows, and to correlate these findings with microradiographic evaluation of bone.
Cuticular Ridges in a Mite
Authors: Crowe John H.
Published: June 2020

Many species of arachnids possess cuticular ridges, the function of which is not known. In the present investigation the structural properties of the ridges in a Trombidiform mite, Panonychus citri were studied, with a view towards discovering the function of the ridges.

For scanning electron microscopy the animals were mounted on metal pos s previously coated with conducting silver paint. Best results were obtained by examining live animals, mounted on the posts immediately before examination. For transmission electron microscopy the animals were fixed in cacodylate-buffered glutaraldehyde, post-fixed in osmium, embedded in Spurr's low viscosity epoxy resin, and sectioned on diamond knives.
Granular Cell Myoblastoma: Ultrastructural Evidence Favoring a Neural Origin
Authors: Mackay Bruce , Valenzuela Jorge , Cox Joyce E.
Published: June 2020

Granular cell myoblastoma is an uncommon tumor that has been reported in a wide variety of anatomical locations. It was first described in 1926 and was termed myoblastoma because of the supposed resemblance between the elongated granular tumor cells and embryonic skeletal muscle. It is now generally agreed that the term is a misnomer, but argument continues over the nature and tissue of origin of this intriguing neoplasm. A number of reports describing the fine structure of the tumor have suggested that it may be of neural or of histiocytic origin. We have recently studied three cases with the electron microscope and have observed what we believe to be convincing morphological evidence of the neurogenic nature of the tumor.
Virus-Like Particles in Leukemic AKR/J Mice as Revealed by Freeze Etching
Authors: Silver Burton B. , Goldstein Allan L.
Published: June 2020

Leukemic and normal mice of the AKR/J strain, infected with Gross leukemia virus, were examined for electron microscopy using the freezeetch technique. The leukemic mice all had lymphocyte counts in excess of 25,000/mm3 and hyperplastic lymph nodes, spleen and thymus.

The lymphatic tissues from normal and leukemic animals were strained through a fine fiberglass screen into phosphate-buffered saline at 4°C. The cells were centrifuged at 200XG at 4°C, the pellet was resuspended in phosphate-buffered saline with 25% glycerol and allowed to incubate in the glycerol solution for two hours before final centrifugation at 500XG. The glycerinated specimen was first frozen in Freon 22 and finally in liquid nitrogen. Freeze etching was carried out in a Denton apparatus at a pressure of 106 TORR and 100°C for one minute.
A Freeze-Fracture Study of Ozone-Induced Morphological Changes in Primate Lung
Authors: Hyde Dallas M.
Published: June 2020

Previous studies of acute exposures of rats and other mammals to ozone demonstrated severe pulmonary parenchymal lesions in the central region of the pulmonary acinus and extensive edema. In this study, an adult Rhesus monkey was exposed to 4 ppm ozone for 4 hours and euthanized immediately after the exposure. A control Rhesus monkey was also euthanized. The lungs were fixed via the trachea at 30 cm of water pressure with Karnovsky's fixative. Tissue was selected from acini of the right diaphragmatic lobes. Much of the selected tissue in the exposed primate was edematou.s. Tissue blocks (1mm2 × 2mm) were immersed in a cryoprotective agent (25% glycerol/0.2 M cacodylate buffer) for 2 hours, mounted in apposed specimen holders, and rapidly frozen in Freon 22 (cooled in liquid nitrogen).
Pulmonary Ultrastructural Changes After Aspiration of Blood
Authors: Popovic N.A. , Bielke S.R. , Huber G.L. , Mullane J.F.
Published: June 2020

Many causes may contribute to the presence of blood in alveolar spaces. Lung contusion or penetration with sharp objects, aspiration of blood following maxillofacial injury or gastric hemorrhage, pulmonary disease conditions such as tuberculosis or neoplasia may all result in intrapulmonary accumulations of blood. Recent experimental work on effects of intra-alveolar blood on pulmonary antibacterial defense has shown that intratracheal injection of whole blood was followed by impaired intrapulmonary bacterial inactivation at 15(90.5 vs. 52.4%, p>.001) and 38(89.8 vs. 52.3%, p>.001) hours. In addition, significant increase in lung wet weight and decrease in fractional lung water content occurred in experimental animals 15 and 38 hours following aspiration of blood. However, arterial pH, pO2 and pCO2 were similar in both the experimental and control groups.
An Electron Microscopic Study of Mast Cells in Human Kidneys
Authors: Mandal A. K. , Nordquist J. A. , Muehrcke R. C. , VoIini F. I.
Published: June 2020

Mast cells are widely distributed throughout the body and normally are present in almost every organ. Although mast cells are absent in normal kidneys, large numbers have been reported in kidneys with chronic inflammatory diseases. The granules in cutaneous mast cells show a positive flourescence for dopamine and norepinephrine suggesting that these cells may contain vasopressor substances. The purpose of these studies was to determine the characteristics and frequency of mast cells in the kidneys of patients with renal disease and hypertension.

Renal tissues from 25 patients with a variety of renal and urinary tract disorders were studied using electron microscopy (RCA, EMU3H). Tissue was obtained by percutaneous biopsy in 17 cases, by nephrectomy in 6 and by autopsy in 2.
Unusual Ultrastructural and Immunologic Findings in a Case of Membranous Glomerular Disease With Renal Vein Thrombosis
Authors: Deodhar Sharad D. , McCormack Lawrence J. , Osborne Dallas , Gifford Ray W.
Published: June 2020

Membranous glomerular disease with nephrotic syndrome is a well recognized complication of renal vein thrombosis. The mechanisms involved in the production of the glomerular lesion are not well understood, however, immunologic injury has been suggested to play an important role. The case which we wish to report is of special interest because of unusual ultrastructural and immunologic findings. A 72-year old man was first seen here eight years ago because of nephrotic syndrome with proteinuria of 6 to 8 gm/24 hours, serum albumin of 1.5 gm % but with normal renal excretory function. Further studies demonstrated bilateral renal vein thrombosis with the thrombus extending from the inferior vena cava. Renal biopsy showed a diffuse membranous glomerular lesion by light microscopy and immunofluorescent studies showed a diffuse linear deposition of immunoglobulin IgG, complement (C'3) and fibrinogen. The latter finding was consistent with immunologic injury at the basement membrane level.
Morphology of Human Amniotic Fluid Cells
Authors: Cutz E. , Conen P. E.
Published: June 2020

Prenatal diagnosis of many inherited diseases is based on studies using cultured AF cells, and therefore morphologic studies on amniotic fluid (AF) cells have increased in importance. However, the nature, morphology and origin of AF cells which grow in tissue culture remains unsettled. In this study AF cells from the first trimester of pregnancy were examined by light, transmission (TEM) and scanning electron microscopy (SEM).

Amniotic fluids (15-20 weeks of gestation) were examined from 11 patients undergoing therapeutic saline abortions and from four intact amniotic sacs with a foetus. Percentages of dead cells were determined using Trypan blue stain, and differential cell counts were made using cytocentrifuge sedimented AF cells stained by Wright's stain and PAP stain.
Fibroblasts During Hypertrophic Scar Formation and Resolution
Authors: Kischer C. W.
Published: June 2020

The morphology of the fibroblasts changes markedly as the healing period from burn wounds progresses, through development of the hypertrophic scar, to resolution of the scar by a self-limiting process of maturation or therapeutic resolution. In addition, hypertrophic scars contain an increased cell proliferation largely made up of fibroblasts. This tremendous population of fibroblasts seems congruous with the abundance of collagen and ground substance. The fine structure of these cells should reflect some aspects of the metabolic activity necessary for production of the scar, and might presage the stage of maturation.

A comparison of the fine structure of the fibroblasts from normal skin, different scar types, and granulation tissue has been made by transmission (TEM) and scanning electron microscopy (SEM).
Preparation of Articular Cartilage for Scanning Electron Microscopy
Authors: Zimny M. L. , Redler I. , Fernandez J.
Published: June 2020

The relationship between tissue preparation and a scanning electron microscopic image is still somewhat nebulous. For purposes of answering comments about our observations of articular cartilage, we decided to prepare tissue samples from one area of a femoral condyle, obtained at surgery, in several ways. As a result of this investigation we hoped to find the best way to prepare articular cartilage for maximal visual detail and subsequently standardize our procedures for a comparative study of normal and arthritic cartilage.

The samples were fixed as follows: (1) no fixative; (2) 2% glutaraldehyde buffered with cacodylate, pH 7.4; (3) 10% buffered formalin; (4) 0.1% glutaraldehyde in Ringer's; and (5) 1% glutaraldehyde in Ringer's.
Electron Microscopy of Simian Lung Mites (Pneumonyssus Simicola)
Authors: Kim James C. S.
Published: June 2020

Despite the demonstrated high incidence of lung mite infection in Old World monkeys, almost nothing is known of the life history and physiology of the parasite or the pathogenesis or the ecology of the disease. It is recognized that international quarantine regulation would not prevent importation of internal parasite such as lung mite. This raises serious concern as ticks and mites are arthropod which serve as both true reservoir and vectors.

There is no published work of the ultrasturcture of Mesostigmata organs or tissues. In addition, urgent needs exist to rule out the possibility of this parasite acting as possible vector of unknown pathogens which has not been introduced to this country.
A Scanning Electron Microscopy Study of Sense Receptors of Cardiochiles Nigriceps (Hymenoptera)
Authors: Norton W. N. , Vinson S. B. , Thurston E. L.
Published: June 2020

Antennal flagellar chemoreceptors of parasitic Hymenoptera function in such various capacities as courtship, host detection and selection. Chemoreceptors are classified according to the thickness of their cuticular wall as determined by the uptake of dye and monitored by light microscopy. A thickwalled chemoreceptor usually possesses a single small opening at the tip, whereas a thin-walled chemoreceptor possesses many small openings in the cuticle. Slifer employed this morphological distinction in her investigations of the sense organs of the parasitic wasp Nasonia vitripennis.

Scanning electron microscopy of C. nigriceps flagellar sense receptors has provided knowledge concerning their morphology, abundance and distribution.
Neuronal and Extraneuronal Uptake of 3H-Norepinephrine in the Heart of the Active Bat: An Electron Microscopic Radioautographic Study
Authors: Hagopian Martin , Gershon Michael D. , Nunez Eladio A.
Published: June 2020

The ability of cardiac tissues to take up norepinephrine from an external medium is well known. Two mechanisms, called Uptake and Uptake respectively by Iversen have been differentiated. Uptake is a high affinity system associated with adrenergic neuronal elements. Uptake is a low affinity system, with a higher maximum rate than that of Uptake. Uptake has been associated with extraneuronal tissues such as cardiac muscle, fibroblasts or vascular smooth muscle. At low perfusion concentrations of norepinephrine most of the amine taken up by Uptake is metabolized. In order to study the localization of sites of norepinephrine storage following its uptake in the active bat heart, tritiated norepinephrine (2.5 mCi; 0.064 mg) was given intravenously to 2 bats. Monoamine oxidase had been inhibited with pheniprazine (10 mg/kg) one hour previously to decrease metabolism of norepinephrine.
Evidence For a Norepinephrine Pool Enhancing Factor in Purified Adrenergic Vesicles: A Functional Macromolecular Form of Dopamine β-Hydroxylase?
Authors: Thureson-Klein Å. , Klein R. L. , Yen S. S. , Lagercrantz H.
Published: June 2020

Highly purified, 750A, dense-core vesicles from bovine splenic nerve can be prepared with a norepinephrine(NE) content of 100 nmoles/mg protein-'. Upon incubation at 30°C, however, the NE is rapidly lost from two pools with halflives of ∼ 4 and 35 minutes, even in the presence of ATP. Loss from the slower, ATP-sensitive pool accounts for 807o of the total vesicle NE and is accompanied by decrements in vesicle matrix density viewed at the ultrastructural level. It is known that the density of the matrix substance parallels semi-quantitatively the vesicle NE content under these conditions.

A search was undertaken for factors which normally stabilize vesicle NE content in vivo, but are lost with the neuroplasm or from the vesicles during purification.
The Application of Stereological Methods to the Study of Drug-Induced Changes in Cells
Authors: Bolender R.P.
Published: June 2020

Ideally, the cell biologist would like to find ways in which morphological and biochemical data can be used synergistically to study cells under normal, experimental, and pathological states. With such a system, it would then be possible to begin to study the intricate relationships of cellular structure to function. The factor limiting such a combined approach has been the virtual absence of quantitative structural information. Fortunately, however, a technique, called stereology, exists which allows one to obtain three dimensional information about cellular structures from 2 dimensional micrographs. This report will demonstrate how these methods can be applied to experimental pharmacology.
Fine Structure of the Granulosa Lutein Cells of Pregnancy in Carnivora
Authors: Sinha Akhouri A.
Published: June 2020

The ultrastructure of granulosa lutein cells of pregnancy from 10 raccoons (Procyon lotor), 8 crabeater seals (Lobodon carcinophagus), 3 black bears (Ursus americanus), a palm civet (Paradoxurus hermaphroditus) and a dog (Canis familiaris) was studied. Fetuses ranged from 10-130 mm crown rump length (CR) in raccoons, 15-180 mm CR in seals, 150-190 mm CR in bears, H O mm CR in civet and near term in dog. The cells possess abundant smooth endoplasmic reticulum (ER), variable amounts of mitochondria with tubular and lamellar cristae, a small amount of lipid droplets and folded plasma membranes (Figs. 1-5) much as in other steroid-secreting tissues. However, variations in the arrangements of smooth ER, mitochondria, lipid droplets and plasma membranes are observed throughout pregnancy. For example, in the civet plasma membranes have a few folds but they are highly specialized and complexly folded in the seals and raccoons especially near the capillaries (Fig. 3).
The Ultrastructural Basis For Increased Prolactin Synthesis and Release From Anterior Pituitary Glands of Estrogen-Progesterone Primed Ovariectomized Rats: Correlated Electron Microscopy and Radioimmunoassay
Authors: Coates P. W. , Blake C. A. , Maxwell D. S. , Sawyer C. H.
Published: June 2020

In rats, physiological studies show that ovariectomy results in a reduced concentration of circulating prolactin. Conversely, ovariectomized rats given estrogen have elevated serum prolactin and increased amounts of prolactin in the anterior pituitary gland. Separate electron microscopic studies suggest modifications in fine structure of prolactin producing (LTH) cells based on relatively large cumulative amounts of estrogen given alone or with comparably high doses of progesterone to adult virgin female or ovariectomized rats. This study was undertaken to provide a correlated morphological and physiological investigation of LTH cells and prolactin levels in a model commonly used by many researchers.

Six to seven weeks after bilateral ovariectomy, a group of adult female rats was primed by a subcutaneous injection of 50 ng of estradiol benzoate and 25 mg of progesterone.
High Resolution Lattice Images of Ferritin Core Crystallites
Authors: Massover William H. , Cowley John M.
Published: June 2020

The iron containing mineral forming the core of the macromolecular iron storage protein, ferritin, is known to be at least partly organized into the crystalline state by virtue of studies of its x-ray and electron diffraction. Towe and Bradley have proposed a lattice model with octahedrally coordinated iron atoms; one of every four interlayers between the planes of close-packed oxygen groups is postulated to have a variable occupancy of the iron atoms. Harrisonet al. have proposed a model which has both tetrahedral and octahedral coordination, with the iron atoms being equally distributed among all of the possible sites between the planes of oxygen groups. Lattice imaging of the ferritin cores by electron microscopy could allow distinction between these two models. Thus far, no observations of lattice planes in the cores have been reported from studies using bright field imaging.
A Return to the Chloride Cell
Authors: Hughes Charles
Published: June 2020

The body fluids of marine teleosts are hypotonic to seawater and these fish are in constant danger of dehydration. Osmoregulation is achieved through the drinking of seawater, the absorption of monovalent ions by the intestinal epithelium, and the secretion of these ions into the sea. Since the fish kidney is not capable of producing a urine hypertonic to the blood, an extrarenal site has been postulated for the salt secretion. Classic studies by Keys and by Krogh had indicated that the gill was most likely responsible for this secretory function and a search began for its cytological basis. In euryhaline fish, Keys and Willmer originally described an eosinophilic, ‘chloride secretory’ cell in the branchial epithelium optimally located between the blood capillaries and the ambient medium. Others, however, claimed that the so-called chloride cell was merely a transitional form of other cell types.
Crystals in Pulmonary Alveolar Macrophages in Aged Mice
Authors: Hertweck M. Sue , Loosli Clayton G. , Hung Kuen-Shan
Published: June 2020

Crystalline deposits observed by light microscopy in the alveolar spaces and in pulmonary macrophages in old C57/bl mice breathing filtered or ambient Los Angeles air has been reported. This report describes crystalline intracellular deposits seen in macrophages for the first time by electron microscopy in old SPF Swiss mice (20-24 months) CD-I strain living in synthetic smog (SS) or filtered air (FA). More were found in the lungs of the SS exposed mice.

For this study, the lungs of mice sacrificed intraperitoneaIly with diabutol injection were inflated with 2% glutaraldehyde, post-fixed in 1% osmic acid, and processed for electron microscopy. The cytoplasm of the macrophages had characteristic cell organelles and inclusions. In addition, varying numbers of elongated crystals were dispersed throughout the cytoplasm (Fig. 1).
Morphological Aspects of Spermatozoan Cytoplasmic Droplet in Some Plethodontid Salamanders
Authors: Murphy Judith A. , Wortham J.W.E. , Martan J. , Thompson Mary R.
Published: June 2020

Ultrastructural studies of cytoplasmic droplets of various mammalian spermatozoa(bull, ram, rabbit, rat, and bat) have revealed only numerous membranous vesicles and tubules in their matrix. The simpl icity of the ultrastructure and lack of other organelles and inclusions in the droplet matrix led researchers to doubt suggestions that cytoplasmic droplets contain endogenous substrates for epididymal spermatozoa survival. Recently, however, biochemical and cytochemical analysis of cytoplasmic droplets in spermatozoa of different domestic animals showed a rather high activity of hydrolytic and glycolytic enzymes.

In our study of interspecific variation in sperm morphology within the salamander family Plethodontidae, it was observed that spermatozoa of all examined plethodontid species have a characteristic cytoplasmic droplet. Cytoplasmic droplets of 16 species were examined with the light microscope and in addition, Plethodon qlutinosus was examined with the TEM.
The Pituitary Response to Stress: An Immunocytochemical - Cytophysiologic Study
Authors: Moriarty Gwen C. , Moriarty C. M.
Published: June 2020

Physiologic studies have shown that there is a peptide in mammalian neurointermediate lobes with immunologic and biologic properties similar to adrenocorticotropin (ACTH). Immunocytochemists have localized the peptide in the secretory granules of the intermediate lobe parenchymal cells and in rostral zone anterior lobe ACTH cells. [Moriarty, G. C. and Halmi, N. S., Z. Zellforsch 132:1 (1972)].

In an attempt to determine the physiologic significance of this peptide, we rapidly removed the pituitaries from intact and adrenalectomized rats which were stressed by ether (2 minutes) or a buzzer (30 minutes). The neurointermediate lobes were separated from the anterior lobes and prepared for electron microscopy and immunocytochemistry (with the unlabeled antibody peroxidase-antiperoxidase complex technique) and ACTH bioassay (with the use of dispersed adrenal cells according to Sayers et al.) and radioimmunoassay.
Cytochemical Studies of Protein Uptake by Adrenal Cortical Cells of the Golden Hamster
Authors: Hillman J. R. , Seliger W. G. , Burk P. E.
Published: June 2020

In a previous histochemical study, high levels of acid phosphatase were found in the developing adrenal cortex of the golden hamster. The present study describes the cytochemical localization of acid phosphatase and thiamine pyrophosphatase in the adult animal. These localizations are then related to protein uptake by adrenal cortical cells using the exogenous horseradish peroxidase as a tracer protein. Animals were sacrificed at times ranging from 15 minutes to 24 hours after injection of peroxidase. The techniques described by Novikoff et al. were utilized for localization of acid phosphatase and thiamine pyrophosphatase.

In acid phosphatase preparations (Fig. 1), dense bodies containing reaction product are found in the cytoplasm of most cortical cells and are often associated with small coated vesicles near the Golgi area. Acid phosphatase activity is present in cells of the zona glomerulosa as well as those of the other two cortical zones.