Qiagen QIAcuity 911000 User Manual page 148

with the maximal values presented from 0 to maximal fluorescence intensity of selected channel
measured. The user can change the range of the x- and the y-axis by modifying the upper value of
the fluorescence intensity on the x- and y-axis. For this the user clicks on top of the y-axis / on the
right of the x-axis, which opens a text box each. The text box is used to insert the new upper range
of the fluorescence intensity. The view of the histogram is adapted accordingly. Resetting the x- and
y-axis to the default range is provided by using the related Reset Axes icon of the tool bar.
To view an additional toolbar that enables you to perform actions related to the 2D Scatterplot
view, such as downloading the plot, hold the pointer over the diagram. For more details about the
toolbar, refer to Diagram options
The Common threshold field for each axis shows the Common threshold value for each selected
well of the fluorescence intensity that is used to distinguish between positive and negative partitions.
If only one source well is selected, the values of the thresholds for the targets or channels on each
axis are shown in the Common threshold fields and on the graph in the form of red lines. If multiple
source wells are defined and their automatically calculated threshold values are different, a
Common threshold value is initially not shown.
Setting the Common thresholds for all selected wells and each axis (channel)
The 2D Scatterplot view provides an option to set a common threshold value for the x- and y-axis
for all associated wells. There are two ways to change the threshold. The first one involves pointing
to the chart, which triggers the appearance of two perpendicular dotted lines. Once the dotted lines
are in the appropriate spot, click the chart. The lines become solid, and the threshold value is
updated, and shown in the Threshold field. To change the value again using this method, click one
of the red lines, and drag it to the appropriate spot. If needed, repeat this step with the second line.
In addition to moving the lines, you can also directly edit the value in the Common threshold field
of the associated axis. Click the Recalculate button to trigger the re-analysis of data
For each partition point the assignment to its group (++, +-, -+ or --) is derived from the threshold
values. The color of the point that represents the partition fluorescence measurement is assigned
according to the group. A legend is shown on the left side below the 2D Scatterplot view:
Dark blue: Partition is assigned for x-axis and y-axis channel as positive (++).

Orange: Partition is assigned to x-axis channel as negative and for y-axis channel as positive

(-+).
Light blue: Partition is assigned to x-axis channel as positive and for y-axis channel as

negative (+-).
Grey: Partition is assigned for x-axis and y-axis channel as negative (--)

QIAcuity User Manual 07/2020 148