Databases and Systems

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This defines a viewing directionand corresponding rotation matrix R0 by
cos( ) = n Iz
and tan( ) =n1y / nIx and hence
The new viewing angles are then given by cos( = nz and tan ( ) = ny/n x,
and are parametrised by which ranges from 0 to 2 .
The second means of navigation is to use fiducial points,i.e.points that have been
previously defined and exist in the Atlas database for the purposes of navigation.
Selecting a single point defines a rotation center, two points will define a line as
above and a third will fully define a plane.
Other navigational support is provided by a 3D feedback window (see figure 5) in
which the section plane is displayed relative to the image bounding box and selected
anatomical structures.
Data Submission
The Edinburgh Mouse Atlas has been developed primarily to support a geneexpression
database by providing a spatial framework for the mapping expression
and anatomical information. The methods for mapping spatially organized data onto
the reconstructions can be categorized under the headings: text, painting or warping.
Text submission:
The spatial domain is described by listing anatomical components or existing
database entries. Typically the user will define a domain by selecting anatomical
components with the assumption the required domain is the union of the component
domains (which by definition do not intersect). If in addition the user wishes to use
predefined gene-expression domains these can be used to refine the new domain by
using the set operations union, intersection and difference on the corresponding sets
of voxel locations.