query rally using node WS-API to search for changes between two dates

I am trying to use Rally WS-API to fetch those User stories and Features that were changed between two dates. The closest I got was getting to the Revision. But I am not sure on how to get the features and User stories from It. Thanks in advance

<pre>
==Request==
    restApi.query({ 
        type: 'Revision',
        query: queryUtils.where('CreationDate', '>=',’2015-03-01’), 
        fetch: ['FormattedID',      'Name','Release','State','RevisionHistory','Revisions','PortfolioItem/Feature','ObjectID','VersionId'],
            scope: {
                workspace: 12345,
                project: 54321
             }  
    })
</pre>
<pre>
==Response==
    {
   _rallyAPIMajor:'2',
   _rallyAPIMinor:'0',
   Errors:[

   ],
   Warnings:[

   ],
   TotalResultCount:2,
   StartIndex:1,
   PageSize:2,
   Results:[
      {
         _rallyAPIMajor:'2',
         _rallyAPIMinor:'0',
         _ref:'http://ift.tt/1wToSI2',
         _refObjectUUID:'98e0ff40-34cb-494f-afc3-3cfeefdd1ce1',
         _objectVersion:'1',
         ObjectID:31480953333,
         VersionId:'1',
         RevisionHistory:{
            _rallyAPIMajor:'2',
            _rallyAPIMinor:'0',
            _ref:'http://ift.tt/18LvXVH',
            _refObjectUUID:'dc6978c3-9fa1-4c24-b900-01d5aedd6007',
            _objectVersion:'1',
            ObjectID:31276441234,
            VersionId:'1',
            Revisions:{
               _rallyAPIMajor:'2',
               _rallyAPIMinor:'0',
               _ref:'http://ift.tt/18LvW4l',
               _type:'Revision',
               Count:7
            },
            _type:'RevisionHistory'
         },
         _type:'Revision'
      },
      {
         _rallyAPIMajor:'2',
         _rallyAPIMinor:'0',
         _ref:'http://ift.tt/1wToSI6',
         _refObjectUUID:'4b41e138-9026-46e7-ac24-94b7dd0765f8',
         _objectVersion:'1',
         ObjectID:31484636333,
         VersionId:'1',
         RevisionHistory:{
            _rallyAPIMajor:'2',
            _rallyAPIMinor:'0',
            _ref:'http://ift.tt/18LvXVW',
            _refObjectUUID:'1142d961-8928-4a9e-8ca1-bc6dd6df17b7',
            _objectVersion:'1',
            ObjectID:31283675555,
            VersionId:'1',
            Revisions:{
               _rallyAPIMajor:'2',
               _rallyAPIMinor:'0',
               _ref:'http://ift.tt/1wToSYo',
               _type:'Revision',
               Count:4
            },
            _type:'RevisionHistory'
         },
         _type:'Revision'
      }
   ]
}
</pre>