scholarly journals Correlative light and backscattered electron microscopy of bone -Part II: Automated image analysis

Scanning ◽  
2006 ◽  
Vol 22 (6) ◽  
pp. 337-344 ◽  
Author(s):  
Haviva M. Goldman ◽  
Aron Blayvas ◽  
Alan Boyde ◽  
Peter G. T. Howell ◽  
John G. Clement ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Image Analysis ◽  
Automated Image Analysis ◽  
Backscattered Electron

scholarly journals Application of Automated Image Analysis to the Study of Cement Paste Microstructure

1994 ◽  
Vol 370 ◽  
Author(s):  
David Darwin ◽  
Mohamed Nagib Abou-Zeid
Keyword(s):  
Image Analysis ◽  
Silica Fume ◽  
Cementitious Material ◽  
Automated Image Analysis ◽  
Mineral Admixtures ◽  
Partial Replacement ◽  
Size Distributions ◽  
Cement Pastes ◽  
Backscattered Electron ◽  
Hydration Phases

AbstractDigital acquisition and analysis of backscattered electron images provide powerful tools for the study of cement-based materials. The techniques can provide useful information on hydration phases, size distributions of unhydrated particles and voids, effects of changes in the watercementitious material ratio and the use of mineral admixtures, and the distribution of microcracks. The results of automated analyses of cement pastes with different water-cement ratios and pastes containing silica fume are presented. The analyses demonstrate that microstructural data vary significantly from image to image, requiring multiple images to limit the effects of scatter. The analyses also indicate that, although the pastes exhibit different degrees of hydration, the size distributions of the unhydrated cement particles are nearly identical. In contrast, the size distribution of larger voids differs significantly as a function of water-cementitious material ratio and with the use of silica fume as a partial replacement for cement. The calcium hydroxide content obtained based on image analysis exceeds but generally parallels that obtained with thermogravimetric analysis. The majority of microcracks in both nonloaded and loaded specimens occur through or adjacent to the lowest density hydration phase.

scholarly journals Analysis of Magnetosome Chains in Magnetotactic Bacteria by Magnetic Measurements and Automated Image Analysis of Electron Micrographs

2013 ◽  
Vol 79 (24) ◽  
pp. 7755-7762 ◽  
Author(s):  
E. Katzmann ◽  
M. Eibauer ◽  
W. Lin ◽  
Y. Pan ◽  
J. M. Plitzko ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Image Analysis ◽  
Magnetic Measurements ◽  
Abiotic Factors ◽  
Magnetotactic Bacteria ◽  
Growth Conditions ◽  
Automated Image Analysis ◽  
Chain Formation ◽  
Content Type ◽  
Unbiased Manner

ABSTRACTMagnetotactic bacteria (MTB) align along the Earth's magnetic field by the activity of intracellular magnetosomes, which are membrane-enveloped magnetite or greigite particles that are assembled into well-ordered chains. Formation of magnetosome chains was found to be controlled by a set of specific proteins inMagnetospirillum gryphiswaldenseand other MTB. However, the contribution of abiotic factors on magnetosome chain assembly has not been fully explored. Here, we first analyzed the effect of growth conditions on magnetosome chain formation inM. gryphiswaldenseby electron microscopy. Whereas higher temperatures (30 to 35°C) and high oxygen concentrations caused increasingly disordered chains and smaller magnetite crystals, growth at 20°C and anoxic conditions resulted in long chains with mature cuboctahedron-shaped crystals. In order to analyze the magnetosome chain in electron microscopy data sets in a more quantitative and unbiased manner, we developed a computerized image analysis algorithm. The collected data comprised the cell dimensions and particle size and number as well as the intracellular position and extension of the magnetosome chain. The chain analysis program (CHAP) was used to evaluate the effects of the genetic and growth conditions on magnetosome chain formation. This was compared and correlated to data obtained from bulk magnetic measurements of wild-type (WT) and mutant cells displaying different chain configurations. These techniques were used to differentiate mutants due to magnetosome chain defects on a bulk scale.

The Use Of Backscattered Electron Microscopy And Image Analysis To Study The Porosity Of Cement Paste

1988 ◽  
Vol 137 ◽  
Author(s):  
Karen L. Scrivener
Keyword(s):  
Electron Microscopy ◽  
Image Analysis ◽  
Cement Paste ◽  
Serial Section ◽  
Three Dimensional ◽  
Two Dimensional ◽  
Image Analyser ◽  
Backscattered Electron ◽  
Solid Phases ◽  
Serial Section Reconstruction

AbstractIn backscattered electron images of polished sections of cement paste pores can be identified down to a size of about 0.05 microns. Moreover, the contrast between pores and the solid phases is sufficient to allow the pores to be distinguished and quantified by an image analyser. There is a good correlation between measures of porosity obtained by this technique and those obtained by methanol absorbtion methods despite the lower limit to resolution.The bse method can also be used to study the distribution of the porosity in space. However, as only two dimensional sections can be examined, there are difficulties in determining the connectivity by this method. The possibility of using serial section reconstruction is examined and discussed.Despite the difficulty in relating two dimensional characterisation to three dimensional properties, several techniques have been used with some success for sandstones. Results from these techniques for cement paste are presented and discussed.

Assessment of cardiac fibrosis: a morphometric method comparison for collagen quantification

2017 ◽  
Vol 122 (4) ◽  
pp. 1019-1030 ◽  
Author(s):  
Julia Schipke ◽  
Christina Brandenberger ◽  
Alexandra Rajces ◽  
Martin Manninger ◽  
Alessio Alogna ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Image Analysis ◽  
Light Microscopy ◽  
Cardiac Fibrosis ◽  
Early Stage ◽  
Method Comparison ◽  
Automated Image Analysis ◽  
Section Thickness ◽  
Quantification Method ◽  
Em Stereology

Fibrotic remodeling of the heart is a frequent condition linked to various diseases and cardiac dysfunction. Collagen quantification is an important objective in cardiac fibrosis research; however, a variety of different histological methods are currently used that may differ in accuracy. Here, frequently applied collagen quantification techniques were compared. A porcine model of early stage heart failure with preserved ejection fraction was used as an example. Semiautomated threshold analyses were imprecise, mainly due to inclusion of noncollagen structures or failure to detect certain collagen deposits. In contrast, collagen assessment by automated image analysis and light microscopy (LM)-stereology was more sensitive. Depending on the quantification method, the amount of estimated collagen varied and influenced intergroup comparisons. PicroSirius Red, Masson’s trichrome, and Azan staining protocols yielded similar results, whereas the measured collagen area increased with increasing section thickness. Whereas none of the LM-based methods showed significant differences between the groups, electron microscopy (EM)-stereology revealed a significant collagen increase between cardiomyocytes in the experimental group, but not at other localizations. In conclusion, in contrast to the staining protocol, section thickness and the quantification method being used directly influence the estimated collagen content and thus, possibly, intergroup comparisons. EM in combination with stereology is a precise and sensitive method for collagen quantification if certain prerequisites are considered. For subtle fibrotic alterations, consideration of collagen localization may be necessary. Among LM methods, LM-stereology and automated image analysis are appropriate to quantify fibrotic changes, the latter depending on careful control of algorithm and comparable section staining. NEW & NOTEWORTHY Direct comparison of frequently applied histological fibrosis assessment techniques revealed a distinct relation of measured collagen and utilized quantification method as well as section thickness. Besides electron microscopy-stereology, which was precise and sensitive, light microscopy-stereology and automated image analysis proved to be appropriate for collagen quantification. Moreover, consideration of collagen localization might be important in revealing minor fibrotic changes.

Rapid estimation of porosity and mineral abundance in backscattered electron images using a simple SEM image analyser

1984 ◽  
Vol 121 (2) ◽  
pp. 81-84 ◽  
Author(s):  
K. Pye
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Image Analysis ◽  
Digital Image Analysis ◽  
Rapid Estimation ◽  
Sem Image ◽  
Quantitative Estimates ◽  
Image Analyser ◽  
Backscattered Electron ◽  
Scanning Electron

AbstractImage analysis is rapidly becoming an integral part of scanning electron microscopy. A number of analogue and digital image analysis systems of varying sophistication are now commercially available for the SEM. This paper illustrates how one such relatively simple system, the IMAS image analyser manufactured by Cambridge Technology, can be used to obtain rapid quantitative estimates of porosity and mineral abundance in backscattered electron images of polished rock sections.

Automated Image Analysis Of Nuclear And Cytoplasmic Changes In Exfoliated Cells From Tracheas Treated With Carcinogen

1977 ◽  
Vol 35 ◽  
pp. 220-221
Author(s):  
S.F. Stinson ◽  
J.C. Lilga ◽  
M.B. Sporn
Keyword(s):  
Image Analysis ◽  
Pattern Analysis ◽  
Relative Proportion ◽  
Automated Image Analysis ◽  
Image Analyzer ◽  
Cross Sectional ◽  
Exfoliated Cells ◽  
Neoplastic Lesions ◽  
Analysis System ◽  
Morphologic Criterion

Increased nuclear size, resulting in an increase in the relative proportion of nuclear to cytoplasmic sizes, is an important morphologic criterion for the evaluation of neoplastic and pre-neoplastic cells. This paper describes investigations into the suitability of automated image analysis for quantitating changes in nuclear and cytoplasmic cross-sectional areas in exfoliated cells from tracheas treated with carcinogen.Neoplastic and pre-neoplastic lesions were induced in the tracheas of Syrian hamsters with the carcinogen N-methyl-N-nitrosourea. Cytology samples were collected intra-tracheally with a specially designed catheter (1) and stained by a modified Papanicolaou technique. Three cytology specimens were selected from animals with normal tracheas, 3 from animals with dysplastic changes, and 3 from animals with epidermoid carcinoma. One hundred randomly selected cells on each slide were analyzed with a Bausch and Lomb Pattern Analysis System automated image analyzer.

Progress In The Practical Application Of Automated Image Analysis To Tem Negatives

1977 ◽  
Vol 35 ◽  
pp. 214-217
Author(s):  
F. A. Heckman ◽  
E. Redman ◽  
J.E. Connolly
Keyword(s):  
Image Analysis ◽  
Image Quality ◽  
Exposure Time ◽  
Image Contrast ◽  
Automated Image Analysis ◽  
Practical Application ◽  
Factors Affecting ◽  
High Image Quality ◽  
Qualitative Evidence ◽  
Comprehensive Study

In our initial publication on this subject1) we reported results demonstrating that contrast is the most important factor in producing the high image quality required for reliable image analysis. We also listed the factors which enhance contrast in order of the experimentally determined magnitude of their effect. The two most powerful factors affecting image contrast attainable with sheet film are beam intensity and KV. At that time we had only qualitative evidence for the ranking of enhancing factors. Later we carried out the densitometric measurements which led to the results outlined below.Meaningful evaluations of the cause-effect relationships among the considerable number of variables in preparing EM negatives depend on doing things in a systematic way, varying only one parameter at a time. Unless otherwise noted, we adhered to the following procedure evolved during our comprehensive study:Philips EM-300; 30μ objective aperature; magnification 7000- 12000X, exposure time 1 second, anti-contamination device operating.

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