WEASEL version 2

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WEASEL version 2 runs on Macintosh OS X and on Windows PC (or any other system) with Java2 installed. A number of the general enhancements have come from suggestions from users of WEASEL version 1. Others, like the improved 2D graphics and printing facility have been enabled by the Java2 environment. Additionally, the rewrite has given the opportunity to add several more sophisticated specialist functions, as shown in the examples below.

Weasel, configured for Macintosh, Windows PC or other systems, is available for public download at WEASEL Download .

An even faster Weasel.

11th August 08: Weasel Version 2.6 is planned to be released within the next 2 months. It has had further tweaking to give further speed increases, particularly for loading of DiVa analysis templates. Several new features have been added: see Weasel Development for more info.

11th December 07: Weasel Version 2.5 has now been released. It has had extensive under-the-hood tweaking to give significant speed improvements. For some file reading and processing operations the speed is up to 2.8-fold faster. Several additional enhancements have also been included: see Weasel Development for more info on the new features.

23rd March 07: Version 2.4 has now been released. Licensed users may continue to use existing codes for this version. Details of enhancements and bug fixes for this and previous versions are at "Weasel Development".

18th April 05: Weasel users are offered the opportunity of guiding future development of the program. We invite you to comment on and vote for your favourites among the many suggestions for enhancement received from users. Go to "Weasel Development".

Major Enhancements introduced in version 2.0:

Population linked displays

This is a method for displaying multi-parameter data by an enhancement of the traditional display formats. Displays are linked by plotting a common, dynamically chosen population in a number of formats and the results are stored as a QuickTime movie.

Pseudo Imaging

In pseudo imaging, the dots of a standard dot plot are replaced by cartoon caricatures or "sprites" or "pseudo images" of the represented cells. Each sprite is circular, of diameter dependent on a selected scaling parameter (usually forward scatter), and coloured with red, green and blue components according to the respective values of up to three parameters (often, but not necessarily, those for reddish, greenish and bluish fluorochromes).

The additive nature of the red, green and blue components is intuitively obvious to most observers who can readily identify yellow as containing red and green components, magenta as red and blue, and cyan as blue and green. Sprites containing all three components are more or less shades of silver-grey, but more subtle colour variations are easily detectable. The 3-component colouring of the example data is shown top centre of the above figure, and its dot sizing at bottom centre. Thus, a 3D pseudo image plot (as shown above right) can potentially display up to 7 measured parameters for each cell; 3-components of colour + dot size + position in 3D.

Curve fitting

While growing out of version1's background subtraction scheme, the fitting is more generally applicable than just for separation of "negatives" from "positives". Several subpopulations can be fitted by analytical functions of the JohnsonSU form as proposed by Lampariello & Aiello (Cytometry 32, 241 '98). To rein in the degrees of freedom, the user may lock any function characteristic in place or require that all subpopulations have identical values of certain characteristics (e.g. skew).

 

CFSE data fitting

This may be regarded as a special form of the curve fitting feature geared to the enumeration of proliferating cells after staining with CFSE or other tracking dyes. The percentage of cells at each division number post staining is output.

 

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