diff --git a/mpm/validation/cylinder_on_inclined_plane/source/MainKratos.py b/mpm/validation/cylinder_on_inclined_plane/source/MainKratos.py
index 7309537f..5429070a 100644
--- a/mpm/validation/cylinder_on_inclined_plane/source/MainKratos.py
+++ b/mpm/validation/cylinder_on_inclined_plane/source/MainKratos.py
@@ -1,5 +1,3 @@
-from __future__ import print_function, absolute_import, division #makes KratosMultiphysics backward compatible with python 2.6 and 2.7
-
 import KratosMultiphysics
 from KratosMultiphysics.MPMApplication.mpm_analysis import MPMAnalysis
 
diff --git a/mpm/validation/cylinder_on_inclined_plane/source/ProjectParameters_contact.json b/mpm/validation/cylinder_on_inclined_plane/source/ProjectParameters_contact.json
index 645680ce..06278120 100644
--- a/mpm/validation/cylinder_on_inclined_plane/source/ProjectParameters_contact.json
+++ b/mpm/validation/cylinder_on_inclined_plane/source/ProjectParameters_contact.json
@@ -19,7 +19,7 @@
             "input_filename" : "cylinder on inclined plane 2d_Body"
         },
         "material_import_settings"        : {
-            "materials_filename" : "MaterialPointsMaterials.json"
+            "materials_filename" : "ParticleMaterials.json"
         },
         "time_stepping"                   : {
             "time_step" : 0.001
@@ -35,7 +35,7 @@
             "input_filename" : "cylinder on inclined plane 2d_Grid"
         },
         "pressure_dofs"                   : false,
-        "auxiliary_variables_list"        : ["NORMAL","IS_STRUCTURE"]
+        "auxiliary_variables_list"        : ["NODAL_AREA","NORMAL","IS_STRUCTURE"]
     },
     "processes"        : {
         "list_other_processes"     : [{
@@ -62,7 +62,7 @@
         }]
     },
     "output_processes" : {
-        "body_output_process" : [{
+        "gid_output_processes" : [{
             "python_module" : "mpm_gid_output_process",
             "kratos_module" : "KratosMultiphysics.MPMApplication",
             "process_name"  : "MPMGiDOutputProcess",
@@ -91,8 +91,7 @@
                     "point_data_configuration"  : []
                 }
             }
-        }],
-        "grid_output_process" : [{
+        },{
             "python_module" : "gid_output_process",
             "kratos_module" : "KratosMultiphysics",
             "process_name"  : "GiDOutputProcess",
@@ -121,6 +120,37 @@
                     "point_data_configuration"  : []
                 }
             }
+        }],
+        "vtk_output_processes" : [{
+            "python_module" : "vtk_output_process",
+            "kratos_module" : "KratosMultiphysics",
+            "process_name"  : "VtkOutputProcess",
+            "Parameters"    : {
+                "model_part_name"                    : "Background_Grid",
+                "output_control_type"                : "step",
+                "output_interval"                    : 5,
+                "file_format"                        : "ascii",
+                "output_precision"                   : 7,
+                "output_sub_model_parts"             : false,
+                "output_path"                        : "vtk_output",
+                "save_output_files_in_folder"        : true,
+                "nodal_solution_step_data_variables" : ["DISPLACEMENT","REACTION"]
+            }
+        },{
+            "python_module" : "mpm_vtk_output_process",
+            "kratos_module" : "KratosMultiphysics.MPMApplication",
+            "process_name"  : "MPMVtkOutputProcess",
+            "Parameters"    : {
+                "model_part_name"                   : "MPM_Material",
+                "output_control_type"               : "step",
+                "output_interval"                   : 5,
+                "file_format"                       : "ascii",
+                "output_precision"                  : 7,
+                "output_sub_model_parts"            : false,
+                "save_output_files_in_folder"       : true,
+                "output_path"                       : "vtk_output_Body",
+                "gauss_point_variables_in_elements" : ["MP_VELOCITY","MP_DISPLACEMENT"]
+            }
         }]
     }
 }
diff --git a/mpm/validation/cylinder_on_inclined_plane/source/ProjectParameters_slip.json b/mpm/validation/cylinder_on_inclined_plane/source/ProjectParameters_slip.json
index 6c5a7773..6239e64d 100644
--- a/mpm/validation/cylinder_on_inclined_plane/source/ProjectParameters_slip.json
+++ b/mpm/validation/cylinder_on_inclined_plane/source/ProjectParameters_slip.json
@@ -19,7 +19,7 @@
             "input_filename" : "cylinder on inclined plane 2d_Body"
         },
         "material_import_settings"        : {
-            "materials_filename" : "MaterialPointsMaterials.json"
+            "materials_filename" : "ParticleMaterials.json"
         },
         "time_stepping"                   : {
             "time_step" : 0.001
@@ -35,7 +35,7 @@
             "input_filename" : "cylinder on inclined plane 2d_Grid"
         },
         "pressure_dofs"                   : false,
-        "auxiliary_variables_list"        : ["NORMAL","IS_STRUCTURE"]
+        "auxiliary_variables_list"        : ["NODAL_AREA","NORMAL","IS_STRUCTURE"]
     },
     "processes"        : {
         "list_other_processes"     : [{
@@ -62,7 +62,7 @@
         }]
     },
     "output_processes" : {
-        "body_output_process" : [{
+        "gid_output_processes" : [{
             "python_module" : "mpm_gid_output_process",
             "kratos_module" : "KratosMultiphysics.MPMApplication",
             "process_name"  : "MPMGiDOutputProcess",
@@ -91,8 +91,7 @@
                     "point_data_configuration"  : []
                 }
             }
-        }],
-        "grid_output_process" : [{
+        },{
             "python_module" : "gid_output_process",
             "kratos_module" : "KratosMultiphysics",
             "process_name"  : "GiDOutputProcess",
@@ -121,6 +120,37 @@
                     "point_data_configuration"  : []
                 }
             }
+        }],
+        "vtk_output_processes" : [{
+            "python_module" : "vtk_output_process",
+            "kratos_module" : "KratosMultiphysics",
+            "process_name"  : "VtkOutputProcess",
+            "Parameters"    : {
+                "model_part_name"                    : "Background_Grid",
+                "output_control_type"                : "step",
+                "output_interval"                    : 5,
+                "file_format"                        : "ascii",
+                "output_precision"                   : 7,
+                "output_sub_model_parts"             : false,
+                "output_path"                        : "vtk_output",
+                "save_output_files_in_folder"        : true,
+                "nodal_solution_step_data_variables" : ["DISPLACEMENT","REACTION"]
+            }
+        },{
+            "python_module" : "mpm_vtk_output_process",
+            "kratos_module" : "KratosMultiphysics.MPMApplication",
+            "process_name"  : "MPMVtkOutputProcess",
+            "Parameters"    : {
+                "model_part_name"                   : "MPM_Material",
+                "output_control_type"               : "step",
+                "output_interval"                   : 5,
+                "file_format"                       : "ascii",
+                "output_precision"                  : 7,
+                "output_sub_model_parts"            : false,
+                "save_output_files_in_folder"       : true,
+                "output_path"                       : "vtk_output_Body",
+                "gauss_point_variables_in_elements" : ["MP_VELOCITY","MP_DISPLACEMENT"]
+            }
         }]
     }
 }
diff --git a/mpm/validation/granular_flow_2D/source/MainKratos.py b/mpm/validation/granular_flow_2D/source/MainKratos.py
index ca7b1b61..76760e23 100644
--- a/mpm/validation/granular_flow_2D/source/MainKratos.py
+++ b/mpm/validation/granular_flow_2D/source/MainKratos.py
@@ -1,5 +1,3 @@
-from __future__ import print_function, absolute_import, division #makes KratosMultiphysics backward compatible with python 2.6 and 2.7
-
 import KratosMultiphysics
 from KratosMultiphysics.MPMApplication.mpm_analysis import MPMAnalysis
 
diff --git a/mpm/validation/granular_flow_2D/source/ProjectParameters.json b/mpm/validation/granular_flow_2D/source/ProjectParameters.json
index 4f5dd05b..b2877200 100644
--- a/mpm/validation/granular_flow_2D/source/ProjectParameters.json
+++ b/mpm/validation/granular_flow_2D/source/ProjectParameters.json
@@ -19,7 +19,7 @@
             "input_filename" : "granular_flow_2D_Body"
         },
         "material_import_settings"           : {
-            "materials_filename" : "MaterialPointsMaterials.json"
+            "materials_filename" : "ParticleMaterials.json"
         },
         "time_stepping"                      : {
             "time_step" : 5e-5
@@ -104,11 +104,11 @@
             "kratos_module" : "KratosMultiphysics.MPMApplication",
             "process_name"  : "MPMVTKOutputProcess",
             "Parameters"    : {
-                "model_part_name"        : "MPM_Material",
-                "output_path"            : "granular_flow_2D_Body",
-                "output_control_type"    : "time",
-                "output_interval"        : 0.01,
-                "gauss_point_results"    : ["MP_VELOCITY","MP_DISPLACEMENT"]
+                "model_part_name"                       : "MPM_Material",
+                "output_path"                           : "granular_flow_2D_Body",
+                "output_control_type"                   : "time",
+                "output_interval"                       : 0.01,
+                "gauss_point_variables_in_elements"     : ["MP_VELOCITY","MP_DISPLACEMENT"]
             }
         }
         ],