Dugwayâs Chemical Test Division successfully tests JCAD system on Stryker. Caged in a menacing looking metal grid with intricate sensory equipment attached to all sides the Armyâs M113 NBC RV Stryker vehicle sits on a dusty road at Dugway Proving Groundâs target S grid being readied by its crew for testing....
The following conditions are when secondary curvatures of the spine  develop:   Cervical-when the baby starts to hold its head up   Lumbar-when the baby starts to â¦ walk. 4 people found this useful.
secondary curvatures of vertebral column. secondary curvatures of vertebral column. [TA] ventrally convex curves of the vertebral column that develop postnatally in the cervical and lumbar regions: the cervical and lumbar lordoses.