Discrete Vertical Rotator

Use this probe to estimate the volume of small particles in single extremely thin sections (specifically EM samples) obtained through unbiased sampling schemes.

The estimator uses centrioles as the sampling unit and as the vertical axis for the cells being sampled because centrioles are easily recognized and of uniform size between cells (Mironov, 1998). The distance of test points from the centrioles (i.e., vertical axis) is used to estimate the volume of other particles in the cell.

Test systems consist of a grid of lines parallel to the vertical axis, and a grid of points. Points located within each structure of interest are placed into distance classes based on the distance from the vertical axis. The number of points in each distance class is used to generate a volume estimate.

Procedure

  1. Click Probes>All probes>Volume/Area>Discrete Vertical Rotator to open the corresponding window.
  2. Adjust the settings and click OK.
  3. Click the centriole of the cell. A grid of lines and points ("plus" signs) is displayed. The vertical lines are parallel to the vertical axis and represent the distance classes into which the selected points are sorted.
  4. Adjust the vertical axis.
    1. Right-click and select Define Vertical Axis.
    2. Drag the head of the arrow until it is in alignment with the desired vertical axis.
    3. Right-click and select Accept to set the new vertical axis.
  5. Place tick marks by clicking the points that are located within the profiles of particles of interest in the field of view.
    • You don't need to mark the lines; they are for reference only.
    • To change the shape and size of the tick marks, use the Options>Stereology Preferences>Colors and Tick Marks tab.
  6. Once all points are marked within the particles of interest, right-click and click Exit Discrete Vertical Rotator.
  7. To view results, use Probes>Stereology results>Probe run list.

 

See Discrete Vertical Rotator formulas