Determining chromatin structure by computer-aided image analysis

1993 ◽  
Vol 51 ◽  
pp. 222-223
Author(s):  
James B. Olesen ◽  
Carol A. Heckman
Keyword(s):  
Image Processing ◽  
Image Analysis ◽  
Polytene Chromosomes ◽  
Razor Blade ◽  
Preliminary Step ◽  
Pattern Recognition Methods ◽  
Transmission Electron ◽  
Computer Aided ◽  
Microscope Slides ◽  
Glass Microscope

In the present research, we address the problem of how chromatin fibers are ordered in band and interband regions along the length of a Drosophila polytene chromosome. Our approach employs image processing as a preliminary step to amplify the image contrast. Then, computerized pattern recognition methods are used to study how the chromatin is arranged.Polytene chromosomes were isolated from salivary glands and squashed on glass microscope slides. The slides were immersed in liquid nitrogen and the coverslips were removed with a razor blade. Small droplets of a polymer developed in our laboratory called HACH (a mixture of 2- hydroxyhexanedial, carbohydrazide and hydrazine) were then placed over individual chromosome spreads and the slides were left at 26°C overnight to allow for HACH polymerization. HACHembedded samples were removed from the slides, mounted on resin blocks, trimmed and thinsectioned at a thickness of approximately 100 nm. Sections were floated onto formvar-coated gold grids and viewed with a Zeiss 10C transmission electron microscope operated at 80kV.

A New Technique for Characterization of Residual Stresses in Glass Surfaces: Scratch Test Completed with Image Analysis

2008 ◽  
Vol 589 ◽  
pp. 275-280 ◽  
Author(s):  
Szilvia Szeghalmy ◽  
Péter Barkóczy ◽  
Maria Berkes Maros ◽  
Attila Fazekas ◽  
Csaba Póliska
Keyword(s):  
Image Processing ◽  
Image Analysis ◽  
Residual Stresses ◽  
Research Work ◽  
Scratch Test ◽  
Glass Quality ◽  
Computer Aided ◽  
A New Technique ◽  
Glass Surfaces

Residual stresses significantly influence the strength and lifetime of the glass products, therefore their qualification and quantification during production is basically important for evaluating their probable reliability in application. The current paper aims at introducing a novel procedure of the suggested automatic glass quality test based on instrumented scratch test completed with computer aided image analysis. A special emphasis is put on the problem of limited reproducibility and reliability of the image processing, arisen in the first stage of the research work. The latest results consisting in the development of a new algorithm, providing a more reliable evaluation of the test data will be described.

scholarly journals Implementation and Comparison of Image Enhancement Techniques Using Low Resolution IRS-1C LISS III Image

2018 ◽  
Vol 7 (1) ◽  
pp. 61-65
Author(s):  
Rubina Parveen ◽  
Subhash Kulkarni ◽  
V. D. Mytri
Keyword(s):  
Image Processing ◽  
Image Analysis ◽  
Image Enhancement ◽  
Noise Suppression ◽  
Satellite Image ◽  
Input Image ◽  
Future Research ◽  
Color Processing ◽  
Preliminary Step ◽  
Liss Iii

Image enhancement is the primary step in image processing. Image enhancement improves the interpretation and makes the image visually clear. In this process pixels of input image were fine-tuned, so that the results are more suitable for display or further image analysis. Numerical manipulation of digital image includes pre-processing as the preliminary step of analysis. Contrast manipulation, spatial filtering, noise suppression and color processing are different methods of image enhancement. Choosing suitable method for satellite image enhancement depends on the application. This paper aims to compare results of various image enhancement techniques using an IRS-1C LISS III satellite image. It attempts to assess enhancement techniques. Shortcomings and general requirements in enhancement techniques were also discussed. This study gives promising directions on research using IRS-1C LISS III image enhancement for future research.

Principles and Practice of On-Line Data Acquisition For Transmission Electron Microscopy

1990 ◽  
Vol 48 (1) ◽  
pp. 528-529
Author(s):  
R. Tietz
Keyword(s):  
Image Processing ◽  
Image Analysis ◽  
Data Acquisition ◽  
Photographic Plate ◽  
Video Tape ◽  
Dynamic Events ◽  
Camera Systems ◽  
Transmission Electron ◽  
On Line ◽  
Beam Currents

For about 15 years now TV-camera based image acquisition systems have been used in many laboratories. These TV-systems facilitate focusing and stigmating of the instrument at low beam currents and the recording of dynamic events in the microscope with a video-tape recorder. Recently, digital image processing systems have become available which make image accumulation or averaging possible, or which can correct for uneven illumination conditions. This simple image processing is the basis for further image analysis (Automatic control of TEM parameters or real analysis of the specimen).The bottle neck in on-line data acquisition for a TEM is the image pick-up system. Compared to a photographic plate, which has about 10.000 by 10.000 resolved pixels, the resolution of commercial, TV-based camera systems is very poor, in the best case about 500 by 500 pixels. The poor resolution of TV-systems restricts the use of image analysis to objects which do not need large image fields.Fig. 1 illustrates the principles of TV-based image pick-up systems.

scholarly journals Emergence of teleradiology, PACS, and other radiology IT solutions in Acta Radiologica

2021 ◽  
pp. 028418512110510
Author(s):  
Jarmo Reponen ◽  
Jaakko Niinimäki
Keyword(s):  
Image Processing ◽  
Information Technology ◽  
Image Analysis ◽  
Communication Systems ◽  
Historical Review ◽  
Imaging Informatics ◽  
Computer Aided ◽  
Picture Archiving ◽  
Journal Publications ◽  
Picture Archiving And Communication

For this historical review, we searched a database containing all the articles published in Acta Radiologica during its 100-year history to find those on the use of information technology (IT) in radiology. After reading the full texts, we selected the presented articles according to major radiology IT domains such as teleradiology, picture archiving and communication systems, image processing, image analysis, and computer-aided diagnostics in order to describe the development as it appeared in the journal. Publications generally follow IT megatrends, but because the contents of Acta Radiologica are mainly clinically oriented, some technology achievements appear later than they do in journals discussing mainly imaging informatics topics.

Scanning and Transmission Electron Microscopy of Human Red Blood Cells

1969 ◽  
Vol 27 ◽  
pp. 44-45
Author(s):  
A.J. Tousimis ◽  
T.R. Padden
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Blood Cells ◽  
Room Temperature ◽  
Type Specimen ◽  
New Combination ◽  
Human Red Blood Cells ◽  
Transmission Electron ◽  
Microscope Slides ◽  
Scanning Electron

The size, shape and surface morphology of human erythrocytes (RBC) were examined by scanning electron microscopy (SEM), of the fixed material directly and by transmission electron microscopy (TEM) of surface replicas to compare the relative merits of these two observational procedures for this type specimen.A sample of human blood was fixed in glutaraldehyde and washed in distilled water by centrifugation. The washed RBC's were spread on freshly cleaved mica and on aluminum coated microscope slides and then air dried at room temperature. The SEM specimens were rotary coated with 150Å of 60:40- gold:palladium alloy in a vacuum evaporator using a new combination spinning and tilting device. The TEM specimens were preshadowed with platinum and then rotary coated with carbon in the same device. After stripping the RBC-Pt-C composite film, the RBC's were dissolved in 2.5N HNO3 followed by 0.2N NaOH leaving the preshadowed surface replicas showing positive topography.

Automated electron tomography: from data collection to image processing

1995 ◽  
Vol 53 ◽  
pp. 26-27
Author(s):  
Weiping Liu ◽  
Jennifer Fung ◽  
W.J. de Ruijter ◽  
Hans Chen ◽  
John W. Sedat ◽  
...  
Keyword(s):  
Image Processing ◽  
Data Collection ◽  
Structural Information ◽  
Imaging Technique ◽  
Electron Tomography ◽  
Ccd Camera ◽  
Automated Data Collection ◽  
Full Control ◽  
Transmission Electron ◽  
Amorphous Structures

Electron tomography is a technique where many projections of an object are collected from the transmission electron microscope (TEM), and are then used to reconstruct the object in its entirety, allowing internal structure to be viewed. As vital as is the 3-D structural information and with no other 3-D imaging technique to compete in its resolution range, electron tomography of amorphous structures has been exercised only sporadically over the last ten years. Its general lack of popularity can be attributed to the tediousness of the entire process starting from the data collection, image processing for reconstruction, and extending to the 3-D image analysis. We have been investing effort to automate all aspects of electron tomography. Our systems of data collection and tomographic image processing will be briefly described.To date, we have developed a second generation automated data collection system based on an SGI workstation (Fig. 1) (The previous version used a micro VAX). The computer takes full control of the microscope operations with its graphical menu driven environment. This is made possible by the direct digital recording of images using the CCD camera.

Recent developments in automated Transmission Electron MI

1989 ◽  
Vol 47 ◽  
pp. 46-47
Author(s):  
W.J. de Ruijter ◽  
P. Rez ◽  
David J. Smith
Keyword(s):  
Image Analysis ◽  
Computer Image ◽  
Lens Design ◽  
Computer Image Analysis ◽  
Transmission Electron ◽  
Resolution Electron ◽  
Recent Developments ◽  
On Line ◽  
Routine Procedures ◽  
Near Future

There is growing interest in the on-line use of computers in high-resolution electron n which should reduce the demands on highly skilled operators and thereby extend the r of the technique. An on-line computer could obviously perform routine procedures hand, or else facilitate automation of various restoration, reconstruction and enhan These techniques are slow and cumbersome at present because of the need for cai micrographs and off-line processing. In low resolution microscopy (most biologic; primary incentive for automation and computer image analysis is to create a instrument, with standard programmed procedures. In HREM (materials researc computer image analysis should lead to better utilization of the microscope. Instru (improved lens design and higher accelerating voltages) have improved the interpretab the level of atomic dimensions (approximately 1.6 Å) and instrumental resolutior should become feasible in the near future.

Radial mass analysis of unstained STEM images of molluscan hemocyanins

1990 ◽  
Vol 48 (3) ◽  
pp. 810-811
Author(s):  
M.G. Hamilton ◽  
T.T. Herskovits ◽  
J.S. Wall
Keyword(s):  
Image Analysis ◽  
Hollow Cylinder ◽  
Electron Micrographs ◽  
Side View ◽  
Mass Analysis ◽  
Mass Measurements ◽  
Electron Microscopic ◽  
Transmission Electron ◽  
Transmission Electron Microscopic ◽  
Microscopic Studies

The hemocyanins of molluscs are aggregates of a cylindrical decameric subparticle that assembles into di-, tri-, tetra-, penta-, and larger multi-decameric particles with masses that are multiples of the 4.4 Md decamer. Electron micrographs of these hemocyanins typically show the particles with two profiles: circular representing the cylinder viewed from the end and rectangular representing the side-view of the hollow cylinder.The model proposed by Mellema and Klug from image analysis of a didecameric hemocyanin with the two decamers facing one another with collar (closed) ends outward fits the appearance of side-views of the negatively-stained cylinders. These authors also suggested that there might be caps at the ends. In one of a series of transmission electron microscopic studies of molluscan hemocyanins, Siezen and Van Bruggen supported the Mellema-Klug model, but stated that they had never observed a cap component. With STEM we have tested the end cap hypothesis by direct mass measurements across the end-views of unstained particles.

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