Image Analysis Issues and Solutions for High-Density Arrays

2004 ◽  
pp. 215-236
Author(s):  
Anton Petrov ◽  
Soheil Shams
Keyword(s):  
2000 ◽  
Vol 46 (4) ◽  
pp. 339-349 ◽  
Author(s):  
John Smit ◽  
Christopher S Sherwood ◽  
Robin FB Turner

Caulobacters are biofilm-forming members of the natural flora of soil and aquatic environments, which exhibit several characteristics that make them attractive for development of high surface area microbial bioreactors or biosensors. Although caulobacters are well characterized genetically, little is known about their biofilm-forming characteristics as a monoculture, or their tolerance of bioreactor-like conditions. Here we investigated the ability of caulobacters to spontaneously form high-density monolayers on artificial surfaces under a variety of environmental conditions, using phase contrast image analysis to assess biofilm density, and epifluorescence with the vital stain DiBAC(tm) to assess viability. With adequate nutrition, extremely dense monolayers formed within 24-48 h, and maintained near 100% viability in experiments ranging up to 22 days. When areas were abraded to remove cells, repopulation occurred rapidly with characteristics similar to the population of a clean surface. When established monolayers were starved for nutrients, a significant fraction of the cells detached from the surface, and cells remaining on the surface no longer tested as viable. Within 4-6 h of nutrient restoration, however, cells in the monolayer again appeared normal and tested as 100% viable. This is the first demonstration that Caulobacter crescentus is stable and amenable to high density monolayer growth and resists starvation, though some cells may express a programmed response to detach from the surface under severe nutrient limitation.Key words: Caulobacter crescentus, biofilm characterization, image analysis, phase contrast, epifluorescence, vital stains.


TAPPI Journal ◽  
2012 ◽  
Vol 11 (2) ◽  
pp. 19-28 ◽  
Author(s):  
MICHELLE RICARD ◽  
GILLES DORRIS ◽  
SYLVAIN GENDRON ◽  
NATALIE PAGÉ ◽  
DENISE FILION ◽  
...  

A new image analysis-based instrument has been developed for measurement of low density and high density macrocontaminants from recycled pulp or whitewater. The unit is coupled to a pulp classifier that isolates the contaminants from pulp and concentrates them before their transfer to a specialized chamber that further separates the contaminants based on their relative density to water. The low density contaminants float on the water surface, whereas the high density macrocontaminants sink onto the settling plate, where images of both contaminant types are then captured and analysed. Through image analysis, the high density contaminants are further classified into two categories: contaminants that are whitish in color and mainly comprised of stickies are named heavy stickies, whereas contaminants that are blackish in color and comprised of black toners and dark wood components are named dirt. When operating in the online mode with autosamplers delivering the samples to the pulp classifier, the instrument provides macrocontaminant determinations every 15 min. The total count and surface area of both types of macrocontaminants per kilograms of pulp can then be sent by direct link to the mill data control system, allowing an effective follow-up of macrocontaminant changes in process pulps and waters. The unit also allows the user to view images of the contaminants. The analyzer results obtained in terms of number and area of macrocontaminants show a linear relationship with TAPPI T-277 om-07 “Macro stickies content in pulp: the ‘pick-up’ method.”


Author(s):  
Tamer Tandogan ◽  
Gerd U. Auffarth ◽  
Chul Young Choi ◽  
Hyeck-Soo Son ◽  
Ramin Khoramnia

Abstract Purpose To analyse and compare the propensity to form glistenings in 4 different types of hydrophobic acrylic intraocular lenses (IOLs): Alcon AcrySof ® MA60AC, HOYA iSert® PC-60AD, Bausch&Lomb enVista, and Kowa Avansee™ PU6A. Methods We used an accelerated laboratory method to create glistenings. IOLs were first immersed in saline at 45 °C for 24 h and then at 37 °C for 2.5 h. Microvacuole (MV) density and size were documented and calculated using an image analysis program. Results Median density of glistenings [MV/mm2] for Alcon AcrySof ® MA60AC was 623 (range 507–804), for HOYA iSert® PC-60AD 1358 (range 684–2699), for Bausch&Lomb enVista 2 (range 1–2), and for Kowa Avansee™ PU6A 1 (range 1–4). The prevailing MV size was: 0–5 µm for Hoya IOLs, 5–10 µm for Alcon IOLs, 20–50 µm for Bausch&Lomb IOLs, and 5–50 µm for Kowa IOLs. Conclusions Glistenings could be induced in all studied IOLs using the accelerated laboratory method. The Alcon AcrySof ® MA60AC and HOYA iSert® PC-60AD IOLs showed MV of high density, while the glistenings in the Hoya IOLs were smaller in size compared to the Alcon IOLs. The MV density was minimal in the Bausch&Lomb enVista and Kowa Avansee™ PU6A IOLs. The propensity of the Alcon AcrySof ® MA60AC IOLs to form glistenings in vitro correlated with the findings of clinical results that are already published.


Author(s):  
S.F. Stinson ◽  
J.C. Lilga ◽  
M.B. Sporn

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.


Author(s):  
F. A. Heckman ◽  
E. Redman ◽  
J.E. Connolly

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.


Author(s):  
H.P. Rohr

Today, in image analysis the broadest possible rationalization and economization have become desirable. Basically, there are two approaches for image analysis: The image analysis through the so-called scanning methods which are usually performed without the human eye and the systems of optical semiautomatic analysis completely relying on the human eye.The new MOP AM 01 opto-manual system (fig.) represents one of the very promising approaches in this field. The instrument consists of an electronic counting and storing unit, which incorporates a microprocessor and a keyboard for choice of measuring parameters, well designed for easy use.Using the MOP AM 01 there are three possibilities of image analysis:the manual point counting,the opto-manual point counting andthe measurement of absolute areas and/or length (size distribution analysis included).To determine a point density for the calculation of the corresponding volume density the intercepts lying within the structure are scanned with the light pen.


Author(s):  
S. Nakahara ◽  
D. M. Maher

Since Head first demonstrated the advantages of computer displayed theoretical intensities from defective crystals, computer display techniques have become important in image analysis. However the computational methods employed resort largely to numerical integration of the dynamical equations of electron diffraction. As a consequence, the interpretation of the results in terms of the defect displacement field and diffracting variables is difficult to follow in detail. In contrast to this type of computational approach which is based on a plane-wave expansion of the excited waves within the crystal (i.e. Darwin representation ), Wilkens assumed scattering of modified Bloch waves by an imperfect crystal. For localized defects, the wave amplitudes can be described analytically and this formulation has been used successfully to predict the black-white symmetry of images arising from small dislocation loops.


Author(s):  
S. McKernan ◽  
C. B. Carter ◽  
D. Bour ◽  
J. R. Shealy

The growth of ternary III-V semiconductors by organo-metallic vapor phase epitaxy (OMVPE) is widely practiced. It has been generally assumed that the resulting structure is the same as that of the corresponding binary semiconductors, but with the two different cation or anion species randomly distributed on their appropriate sublattice sites. Recently several different ternary semiconductors including AlxGa1-xAs, Gaxln-1-xAs and Gaxln1-xP1-6 have been observed in ordered states. A common feature of these ordered compounds is that they contain a relatively high density of defects. This is evident in electron diffraction patterns from these materials where streaks, which are typically parallel to the growth direction, are associated with the extra reflections arising from the ordering. However, where the (Ga,ln)P epilayer is reasonably well ordered the streaking is extremely faint, and the intensity of the ordered spot at 1/2(111) is much greater than that at 1/2(111). In these cases it is possible to image relatively clearly many of the defects found in the ordered structure.


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