bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quantitative morphological analysis in a SEM‐microcomputer system—II. Morphological analysis of complex SEM images
Authors: Sergeev Y. M. , Spivak G. V. , Sasov A. Y. , Osipov V. I. , Sokolov V. N. , Rau E. I. 
Published: August 2011

SUMMARYThe application of automatic image analysis image techniques in the SEM to massive samples with complex morphology requires a careful choice of the imaging mode and detector geometry used. Thus the quantitative analysis of conjugated surfaces requires summary images, derived from backscattered, secondary, transmitted electron and cathodo‐luminescent signals, as well as dedicated processing algorithms. Careful attention must also be paid to the problems of obtaining and matching these various images.
High resolution structure images around the pole pattern of a bent crystal. Application: deformation of a crystal near a defect
Authors: Cesari C. , Nihoul G. , Yangui B. , Boulesteix C. 
Published: August 2011

SUMMARYThe variation of high resolution structure images with the tilt of the incident electron beam has been studied on bent crystals. By systematically computing images for different situations we show that the aspect of the image can be linked to the angle of tilt of the incident beam, and to the direction of tilt. Good agreement is obtained between micrographs and computed images. As one possible application, we analyse the surroundings of a planar defect.
A unidirectional temperature gradient stage for solidification studies in aqueous solutions
Authors: Kourosh Sohrab , Diller Kenneth R. 
Published: August 2011

SUMMARYA low temperature light microscope stage has been designed and fabricated for quantitative analysis of the solidification of aqueous solutions. Thermal boundary conditions are controlled during freezing so as to enable direct comparison of data with complementary theoretical models. Evolution of the temperature distribution within the system is monitored by a one‐dimensional thermocouple array, and growth of the phase interface is measured via a displacement transducer. The two‐dimensional solution concentration field is assessed by computer densitometric analysis of the grey scale distribution for a light absorbing solute. Experimental and theoretical analyses of freezing processes with the stage correlate well, and the data base is shown to be internally consistent by independent thermal and mechanical measures of the interface velocity.
A study of the effect of solid particle impact and particle shape on the erosion morphology of ductile metals
Authors: Rao P. Veerabhadra , Young Stanley G. , Buckley Donald H. 
Published: August 2011

SUMMARYStudies were conducted to identify the differences in the modes of erosion between impulsive and steady‐jet glass bead erodent particle impingement at normal incidence. A 6061‐T6 aluminium alloy, copper and 1045 steel were used as test materials. A small bore or calibre gas gun apparatus was used for impulse testing and a commercial sand blasting facility was used for steady‐jet impingement testing. Crushed glass was also used as an erodent in the steady‐jet apparatus and the erosion patterns from crushed glass were compared with those of glass bead impingement erosion.Morphological features and material removal mechanisms for the specimens were studied using weight, loss measurements, scanning electron microscope, energy dispersive X‐ray spectroscopy (EDS), and surface profilometry. Impulsive conditions induced more severe damage and results in embedment and fragmentation of glass beads, likely due to more intense pressure pulses and longer loading times on impact. Patterns from steady‐jet glass bead impingement experiments exhibited overlapping of plastically formed craters with very little evidence of particle fragmentation.Recorded profiles and micrographs of the specimens subjected to steady‐jet impingement indicate that crushed glass induced deeper and wider pits than glass beads. The volume loss of 1045 steel was almost half that observed on aluminium and copper specimens with both types of erodent particles. The material removal process for glass bead impingement appears to be in the form of deformation induced fatigue failure with flake‐like debris visible at high magnification. With crushed glass, material appears to have been removed as small chips, leaving a jagged, angular, faceted surface characteristic of ‘cutting wear’.EDS analyses indicated traces of silicon (from the erodent particles) on all three materials. Silicon amounts were maximum at the pit bottom.
A simple and inexpensive liquid helium cooled ‘slam freezing’ device
Authors: Heath I. Brent 
Published: August 2011

SUMMARYA liquid helium cooled copper block device has been designed for the rapid freezing of biological material. The apparatus differs from previous designs in being easily constructed from readily available components. It incorporates a novel and simplified specimen carrying system. Construction of this apparatus is possible for any laboratory and makes the advantages of freeze substitution reliably available for many cell types at minimal cost.
The use of Hanks'‐pipes buffers in the preparation of human, normal leucocytes for TEM observation
Authors: Haviernick S. , Lalague E. D. , Corvellec M.‐R. , Pelletier L. , Calamba A. D. , Derghazarian C. , Cousineau G. H. 
Published: August 2011

SUMMARYIt is suggested that the use of Hanks' + pipes + sucrose buffers, in combination with glutaraldehyde and osmium tetroxide fixatives, represent an excellent mode of preparation of fresh and cultured peripheral blood leucocytes, not only for transmission electron microscopy observation of these cells but also for scanning electron microscopy.
Image processing in a general purpose microcomputer
Authors: Russ John C. , Russ J. Christian 
Published: August 2011

SUMMARYVideo images from light and electron microscopes can be acquired in ‘digital’ form within a personal computer, using standard peripherals and interfaces. In addition to providing for measurement of such images (counting of features by size class, integration of density, etc.) the stored image can be processed in a variety of ways. Using techniques known in the image processing field but only recently practical in such small computers, smoothing of the grey‐scale information, sharpening of edges, extraction of texture information, directional derivatives, and shifts of grey scale can be applied. Combination of images with previous ones stored on disk is especially useful for electron and X‐ray images from SEM. The system described carried out all operations in software, typically requiring times of 1–20 s per image which should be practical in many microscopy laboratories.
The use of a hybrid diffraction unit in the measurement of dislocation densities by electron microscopy
Authors: Ecob R. C. 
Published: August 2011

SUMMARYThe expression used in the electron microscopical measurement of dislocation densities is ϱ=2N/Lt, where N is the number of intersections between the dislocation lines in a TEM image, L the total length of a set of sampling lines superimposed upon that image (corrected for magnification) and t the thickness of the thin foil containing the dislocation structure. During the estimation of ϱ it is therefore important to reduce errors in the measurements of all three variables. It is shown how calibration of the microscope magnification, careful consideration of diffraction conditions and use of the hollow cone and rocking beam facilities on the hybrid diffraction unit fitted to the Philips EM 400T can assist in increasing the speed and accuracy of the measurement procedure.
A simple chamber for observing microscopic specimens in both top and side views
Authors: Boocock C. A. , Brown A. F. , Dunn G. A. 
Published: August 2011

SUMMARYA method is described which permits the observation of microscopic specimens in both top and side views, a rapid change between the two views being possible without disturbing the specimen. The system requires the introduction of simple optical components into a culture chamber, does not restrict the types of microscopy that may be used, and does not necessitate modification of the microscope itself. The technique is discussed in relation to the study of tissue cells in culture, but may find applications in other areas.
A tannic acid based preparation procedure which enables leucocytes to be examined subsequently by either SEM or TEM
Authors: McCarthy D. A. , Pell B. K. , Holburn C. M. , Moore S. R. , Perry J. D. , Goddard D. H. , Kirk A. P. 
Published: August 2011

SUMMARYA modification of the glutaraldehyde‐osmium tetroxide‐tannic acid‐uranyl acetate (GOTU) fixation procedure is described which allows human leucocytes to be examined subsequently by either transmission electron microscopy (TEM) or scanning electron microscopy (SEM).
A new method for obtaining scanning electron microscopic images of the reorganization process of human dermal microvascular endothelium in vitro
Authors: Tsuji Takuo , Karasek Marvin A. 
Published: August 2011

SUMMARYA new method for obtaining scanning electron microscopic images of the reorganization process of endothelial cells has been developed. When covered with a collagen‐coated disk, all the cultured endothelial cells reorganized on the collagen of the disk, which was easily taken out from the dish to process for SEM.The reorganization process could be divided into four stages: endothelial cell growth (Stage 1), reticular network formation (Stage 2), tubular structure formation (Stage 3), and cytolysis of the tube (Stage 4). Between Stages 1 and 2 the endothelial cells transformed from a cobblestone to a spindle‐shaped pattern and fused each other, forming a board‐like structure. Between Stages 2 and 3 break up of parts of the board‐like structure and outflow of a necrotic mass from the centre of the structure occur. At Stage 3 a tubular structure is formed following enwrapping of the cleared centre by the surrounding endothelial cells. This method produces a means to study the angiogenesis in a variety of disorders including tumours and wound‐healing process using SEM.
Penetration rate of glutaraldehyde in various buffers into plant tissue and gelatin gels
Authors: Coetzee J. , van der Merwe C. F. 
Published: August 2011

SUMMARYThe choice of buffer vehicle during fixation with glutaraldehyde influences not only the rate of crosslinking in a bovine serum albumin model system, but also the penetration rate of the glutaraldehyde into plant tissue and gelatin gels. The rate of penetration into plant tissue and the crosslinking rate of bovine serum albumin by glutaraldehyde are independent of each other in any one buffer. Buffer penetration into gelatin gels is not as fast as glutaraldehyde penetration into the same gels. The highest rate of crosslinking of bovine serum albumin by glutaraldehyde is obtained with a buffer vehicle consisting of Na2HPO4 and NaH2PO4. Glutarldehyde concentrations of 2–3% are advised for routine fixation of plant material.
Image analyser measurements of coal reflectance
Authors: Lee James B. 
Published: August 2011

SUMMARYThe application of an image analyser to the rapid measurement of coal reflectance histograms is described. The ability of an image analyser to utilize a two‐dimensional image allows the coal only to be represented in the reflectance histogram, with contribution from the resin used in particulate block specimens eliminated. While the accuracy of reflectance measurement with an image analyser is not as great as can be obtained with a spot photometer system, sufficient accuracy is obtainable for rank determination.
Simple procedures for the transfer of grid images onto glass coverslips for the rapid relocation of cultured cells
Authors: Small J. V. 
Published: August 2011

SUMMARYProcedures are described whereby electron microscope‐grid images may be transferred onto the surface of glass coverslips. By using coordinate grids, patterns are obtained that are ideal for the rapid relocation of cultured cells. Two basic procedures are presented. In the first, metal is evaporated, in a vacuum unit, onto glass coverslips carrying electron microscope grids to produce an exposed, glass replica of the grid pattern. The grid pattern is then etched in the glass surface with hydrofluoric acid and the metal subsequently dissolved away. In the second method silicone monoxide is evaporated onto coverslips carrying a ‘negative grid’ or a negative grid image, to produce a pattern directly visible in the phase contrast or interference microscope. Modifications for scanning electron microscopy are also described.
Choosing the appropriate section thickness in the melamine embedding technique
Authors: Frösch Dieter , Westphal Christel 
Published: August 2011

SUMMARYWhen biological materials are infiltrated by a water‐soluble melamine resin and hardened, they become as hard as glass. This is a prerequisite for extreme thin‐sectioning.In this paper, the structural information from unsupported transparent thin sections of beef liver catalase, calf thymus DNA, horse spleen ferritin, insect muscle and rat microtubules is compared to that of normal thin sections. While ferritin molecules (12 nm diameter), microtubule subunits (8 nm long axis) and catalase crystals (8 nm subunit diameter) appear to become mechanically damaged in a 10 nm section (as measured by resectioning), DNA‐molecules (3 nm diameter) are satisfactorily preserved during sectioning. Remarkably, for electron phase contrast imaging of unstained cross‐sectioned insect muscle, a minimum section thickness of about 30–40 nm is required.
Computer‐based determination of size and shape in living cells
Authors: Marsh Donald J. , Jensen Peter Koch , Spring Kenneth R. 
Published: August 2011

SUMMARYMeasurement of cell volume in living epithelial cells has become an important technique in studies of membrane transport processes that function in cell volume regulation. Planimetry of video images of optical sections enables the measurement of the cross sectional area of each section. Cell volume is calculated from the measured area of each section and the known focus displacements. In the past the measurement of cross section area has been done by manual positioning of a cursor superimposed on the video image. Each experiment generates approximately 200 images in which two or more cells may be analysed. We have developed a computer‐based method that uses one image as a template, and allows automated area determination of successive images by template matching and digital image processing. This new method is comparable to the older method in speed and accuracy, but requires much less effort from the experimenter.
Prolonged ethanol replacement by CO2 increases splits on articular cartilage surface after critical point drying
Authors: Helminen H. J. , Jurvelin J. , Tammi M. , Pelttari A. , Svartbäck C.‐M. , Kiviranta I. , Säämänen A.‐M. , Paukkonen K. 
Published: August 2011

SUMMARYEthanol replacement by CO2 of glutaraldehyde‐fixed and ethanol‐dehydrated rabbit articular cartilage specimens was monitored with both gas chromatograph and alcometer prior to critical point drying (CPD). The surface structure of the patellar specimens was also systematically registered with a semiquantitative scanning electron microscopic method. After a 2 h interval, when about 28 μl of ethanol/15 min CO2 extract was removed, the articular surface was smooth, although small areas of striated surface and superficial splits were present. A long‐term CO2 treatment (16 h) removed ethanol completely, but increased superficial splitting of the articular surface after CPD. Air‐drying of the specimens gave rise to inferior preservation of the cartilage: large areas with pitted and leafy surface qualities, but no superficial splits, were present on the surface. It was evident that prolonged ethanol replacement by CO2, prior to CPD, degraded surface structure of the articular cartilage which should be taken into consideration in the planning and design of experiments. Ethanol removal by CO2 could conveniently be monitored by an alcometer.
Models and observations of fcc/bcc interfaces
Authors: Ecob R. C. 
Published: August 2011

SUMMARYWhereas models of the structure and periodicity of CSL or near CSL high angle grain boundaries are relatively well developed and have been to some extent verified by experiment, the nature of more general (e.g. fcc/bcc) interfaces is very imperfectly understood. One of the major differences between homo‐ and heterophase boundaries is the occurrence, in the latter case, of reproducible orientation relationships due to the crystallographic requirements of phase transformation (e.g. a glissile interface for martensitic growth, low energy interfaces for classical nucleation). A review is given of the relationships commonly observed to obtain between fcc and bcc crystals (as well as ordered phases based upon these structures).Within a given relationship, it is possible to use models of the available interfaces to predict their dislocation content; the success of the various approaches is considered. It is shown that the dislocation arrays identified on fcc/bcc boundaries are consistent with the occurrence of a primary structural relaxation, but that the latter does not appear to be complete. Possible reasons for this are discussed, together with the extent to which secondary structural models may be applicable.Attempts to rationalize the observed orientation relationships and morphologies are discussed, and it is pointed out that these all rely on searches for situations of minimum primary misfit, but that the way in which the latter is quantified determines the results of the analyses. Nevertheless, the implication is that the primary misfit does appear to determine the actual behaviour, though no structural or mechanistic conclusions can safely be drawn from this observation.
Optical fluorescence microscopy in three dimensions: microtomoscopy
Authors: Van Resandt R. W. Wijnaendts , Marsman H. J. B. , Kaplan R. , Davoust J. , Stelzer E. H. K. , Stricker R. 
Published: August 2011

SUMMARYA unique property of confocal fluorescence microscopy is utilized to obtain scanned images of a number of samples in three dimensions. This kind of microscopy for the first time enables the direct study of the 3‐D arrangement of fluorescently labelled materials in living cells. The technique is based on a home build, confocal, scanning laser microscope. The entire volume of the object is scanned mechanically through the well‐defined focus of a laser illuminated, high numerical aperture objective. An identical optical path, arranged confocally, is used to detect the fluorescence emission from the focal volume. A pinhole in the image plane of the detection channel prevents fluorescence light, generated outside the focal volume, to reach the detector. Consequently a true resolution is obtained along the optical axis (identified as z‐axis) and three‐dimensional imaging without the need for mathematical operations is possible. A high resolution along the z‐axis (0.9 μm) is shown as well as in the object plane (0.25 μm) using Rhodamine as the fluorescent dye. The resolution along the z‐axis is explained and experimentally demonstrated using an object which contains only a z‐axis dependent structure. Pictures of sections through living cells are shown, both parallel to the object plane and parallel to the optical axis.
Cryo‐electron microscopy of tropomyosin magnesium paracrystals
Authors: Stewart Murray , Lepault Jean 
Published: August 2011

SUMMARYMagnesium paracrystals of tropomyosin have been examined in thin films of vitreous ice by electron microscopy. This material is radiation sensitive, with damage being located near the molecular ends. However, low‐dose images show a repeating pattern of pairs of dark lines every 40 nm which indicates that the structure has been well preserved. These dark lines are separated by about 15 nm and probably represent extra protein density at the molecular ends. It has not been possible previously to see this feature by electron microscopy. We also demonstrate that the mercurial p‐chloro‐mercuribenzoate (PCMB) attached to the tropomyosin thiol at residue 190 can be detected in unstained paracrystals embedded in vitreous ice.
Quantitative assessment of chemical fixation, including the use of malachite green, for electron microscopy of vacuolate mesophyll cells from leaves of a grass
Authors: Lawton June R. 
Published: August 2011

SUMMARYVarious chemical fixation regimes were studied using leaves of the grass Lolium multiflorum Lam. as a test system. To evaluate the quality of fixation for electron microscopy two parameters were chosen; the extent of cell damage to mesophyll cells and damage and change in size of chloroplasts. Reducing the concentration of glutaraldehyde from 3% to 1% resulted in extensive cell damage. The addition of paraformaldehyde to 1% glutaraldehyde did not totally eliminate cell damage and resulted in dilation of thylakoids within the chloroplasts. In tissue fixed and washed in solutions matched to the total osmolality of the primary fixative solution there was little cell damage but the chloroplasts were larger, diameters 4.5times2.9 μm, than when only the buffer vehicle osmolality was maintained during subsequent washings, diameters 3.5times1.6 μm. Malachite green added to the primary fixative solution abolished cell damage regardless of buffer concentration and resulted in the appearance of osmiophilic droplets on the surface of and within the chloroplasts which were not present in the absence of malachite green. It is suggested that malachite green stabilizes cell membranes during primary fixation.
The microstructure of high‐rank coals at lattice resolution
Authors: Little J. A. , Gronsky R. 
Published: August 2011

SUMMARYThe microstructures of both anthracite and meta‐anthracite have been examined using high resolution electron microscopy. The microstructure of the native, untreated meta‐anthracite shows carbon fibrils consisting of as many as thirty parallel layers and being as long as 30 nm. In comparison with a previous investigation of anthracite microstructures this corresponds to an anthracite heat‐treated to at least 2500°C, or to a soft carbon precursor heated at 1500°C.The anthracite microstructure shows little long‐range ordering but confirms earlier work, and consists of very small stacks of carbon layers in a preferred orientation. However, the low volatility of the anthracite has been used to resolve the interface between the coal and some minerals commonly found in all coal structures and an attempt has been made to use these observations to generalize on the possible catalytic activity of such minerals in other coals used for coal gasification. The interfaces were found to consist of numerous ledges and microledges all of which would increase the surface area of the mineral particle and give rise to high energy sites suitable for enhanced catalytic ability.