The design, development and documentation of software. See software engineer, systems analysis & design, programming, object-oriented programming, software metrics, CASE and Systemantics.
Overview. Posttransplant lymphoproliferative disease (PTLD) is an unusual entity that has many features of an immune system malignancy. It is characterized by uncontrolled proliferation of lymphoid lineage cells (typically B cells, rarely non-B lineage) in a context of posttransplant immunosuppression.
1 Gas tungsten arc welding (GTAW) - also known as TIG (tungsten, inert gas), uses a non-consumable tungsten electrode to produce the weld. 2  The weld area is protected from atmospheric contamination by an inert shielding gas such as Argon or Helium.