breeds [ epi-cell-health epi-cell-sick ] patches-own [ oxy ; oxygen NO cytomix ; mix of IL-1, TNF and IFN-g solute-lumen solute-penetrated p-iNOSmRNA ; patch holder for iNOSmRNA p-NF-kB p-occludin p-occludin-cellwall p-claudin-1 p-claudin-1-cellwall p-ZO-1 p-ZO-1-cellwall p-ZO-3 p-ZO-3-cellwall tight-junction ] turtles-own [ sick pre-occludin occludin-cytoplasm occludin-cellwall pre-claudin-1 claudin-1-cytoplasm claudin-1-cellwall pre-ZO-1 ZO-1-cytoplasm ZO-1-cellwall ZO-2 pre-ZO-3 ZO-3-cytoplasm ZO-3-cellwall tNO ; ; NO debugger to check local levels of NO per turtle iNOSmRNA NF-kB ] globals [ step hours runs total-solute-lumen total-solute-penetrated total-NO total-cytomix total-iNOS total-occludin total-occludin-cellwall total-claudin-1 total-claudin-1-cellwall total-ZO-1 total-ZO-1-cellwall total-ZO-3 total-ZO-3-cellwall total-NF-kB ] to setup ca set step 0 set hours 0 set total-solute-lumen 0 set total-solute-penetrated 0 set-default-shape epi-cell-health "epi-cell-shape-health" set-default-shape epi-cell-sick "epi-cell-shape-sick" ask patches [set oxy 100 set NO 0 set cytomix 0 set solute-lumen 50 set solute-penetrated 0 sprout 1 [set breed epi-cell-health set sick 0 set pre-occludin 40 set occludin-cytoplasm 40 set occludin-cellwall random 120 set pre-claudin-1 40 set claudin-1-cytoplasm 40 set claudin-1-cellwall random 120 set pre-ZO-1 40 set ZO-1-cytoplasm 40 set ZO-1-cellwall random 120 set ZO-2 100 set pre-ZO-3 40 set ZO-3-cytoplasm 40 set ZO-3-cellwall random 120 set tNO 0 ] ] draw-graph if add-NO = true [ifelse NO-scavenger = true [print "NO incubated with NO scavenger" ] [print "NO incubated" ] ] if add-cytomix = true [ifelse NO-scavenger = true [print "Cytomix incubated with NO scavenger" ] [ifelse ethyl-pyruvate > 0 [print "Cytomix incubated with Ethyl Pyruvate" ] [ifelse NAD+ > 0 [print "Cytomix incubated with NAD+" ] [print "Cytomix incubated" ] ] ] ] end to set-scale-pc ask patches [if (mode = 0) ; ; Mode Injury [set pcolor black] if (mode = 1) ; ; bacteria in lumen [set pcolor scale-color violet solute-lumen 0 125] if (mode = 2) [set pcolor scale-color violet solute-penetrated 0 125] if (mode = 3) [set pcolor scale-color blue NO 0 25] if (mode = 4) [set pcolor scale-color green cytomix 0 1.5] if (mode = 5) [set pcolor scale-color blue p-iNOSmRNA 0 20] ] end to injure-NO if (random 441) <= initial-NO [set NO (NO + 0.01) / 0.899 ] end to injure-cytomix if (random 441) <= initial-cytomix [set cytomix cytomix + 0.1 ] end to go set-scale-pc if step = 12 ; 1 Step = 5 minutes [set hours hours + 1 set step 0 ] set step step + 1 ask turtles [epi-cell-function] evaporate solute-diffuse set total-solute-lumen sum values-from patches [solute-lumen / 100] set total-solute-penetrated sum values-from patches [solute-penetrated / 100] set total-NO sum values-from patches [NO] set total-cytomix sum values-from patches [cytomix] set total-iNOS (sum values-from patches [p-iNOSmRNA] / 100) set total-occludin (sum values-from patches [p-occludin]) / 100 set total-occludin-cellwall (sum values-from patches [p-occludin-cellwall]) / 100 set total-claudin-1 (sum values-from patches [p-claudin-1]) / 100 set total-claudin-1-cellwall (sum values-from patches [p-claudin-1-cellwall]) / 100 set total-ZO-1 (sum values-from patches [p-ZO-1]) / 100 set total-ZO-1-cellwall (sum values-from patches [p-ZO-1-cellwall]) / 100 set total-ZO-3 (sum values-from patches [p-ZO-3]) / 100 set total-NF-kB (sum values-from patches [p-NF-kB]) draw-graph if data = true [data-collect] if Add-NO = true [ask patches [injure-NO ] ] if Add-Cytomix = true [ask patches [injure-cytomix ] ] if hours = 49 [ifelse loop-run = true [wait 2 setup ] [stop ] ] end to solute-diffuse diffuse solute-lumen 0.1 diffuse solute-penetrated 0.1 ask turtles [if solute-lumen < 0 [set solute-lumen 0] if solute-penetrated > 100 [set solute-penetrated 100] ] end to epi-cell-function ifelse mode = 0 [showturtle] [hideturtle] mRNA-activation ; ; mRNA activation protein-synthesis ; ; Protein synthesis protein-localization form-tight-junction sum-total-proteins protein-breakdown leak end to leak if sick = 1 [if solute-lumen > solute-penetrated [set solute-lumen solute-lumen - diffusion-rate set solute-penetrated solute-penetrated + diffusion-rate ] if solute-penetrated > solute-lumen [set solute-lumen solute-lumen + diffusion-rate set solute-penetrated solute-penetrated - diffusion-rate ] ] end to iNOS-function set NO (max list (0) (NO + (NF-kB) ) ) set tNO NO end to mRNA-activation ; Interruptions/Augmentations of mRNA activity need to go here set pre-occludin pre-occludin + 1 set pre-claudin-1 pre-claudin-1 + 1 set pre-ZO-1 max list 0 (pre-ZO-1 + 1 - (NO / 100)) set pre-ZO-3 pre-ZO-3 + 1 set NF-kB (cytomix - ethyl-pyruvate - NAD+ ) / 10 set iNOSmRNA max list 0 ( (iNOSmRNA * 0.99 + (NF-kB * 10) ) ) if iNOSmRNA < 0 [set iNOSmRNA 0 ] set p-iNOSmRNA iNOSmRNA set p-NF-kB NF-kB end to protein-synthesis ; Direct effects of compounds on Protien synthesis go here if pre-occludin >= 40 ; 200 minutes [ifelse hours <= 24 [set occludin-cytoplasm max list 0 (occludin-cytoplasm + 1 - NF-kB ) ] [set occludin-cytoplasm max list 0 (occludin-cytoplasm + 1 - (NO / 10)) ] set pre-occludin pre-occludin - 1 ] if pre-claudin-1 >= 40 ; 200 minutes [ifelse hours <= 24 [set claudin-1-cytoplasm claudin-1-cytoplasm + 1 + (NO / 10) + (NF-kB * 10) ] [set claudin-1-cytoplasm claudin-1-cytoplasm + 1 + (NO / 50) ] set pre-claudin-1 pre-claudin-1 - 1 ] if pre-ZO-1 >= 40 ; 200 minutes [set ZO-1-cytoplasm max list 0 (ZO-1-cytoplasm + 1 - (NO / 100)) set pre-ZO-1 pre-ZO-1 - 1 ] if pre-ZO-3 >= 40 ; 200 minutes [ifelse hours <= 12 [set ZO-3-cytoplasm max list 0 (ZO-3-cytoplasm + 1 - (NF-kB * 10 ) ) ] [set ZO-3-cytoplasm max list 0 (ZO-3-cytoplasm + 1 - (NO / 50) ) ] set pre-ZO-3 pre-ZO-3 - 1 ] if iNOSmRNA >= 8 [iNOS-function set iNOSmRNA 8 ] end to protein-localization ; Interruptions of localization go here ifelse occludin-cytoplasm >= 40 [set occludin-cellwall max list 0 (occludin-cellwall + 1 - (max list (NF-kB) (NO / 10))) set occludin-cytoplasm max list 0 (occludin-cytoplasm - 1) ] [set occludin-cytoplasm max list 0 (occludin-cytoplasm - 1) ] ifelse claudin-1-cytoplasm >= 40 [set claudin-1-cellwall max list 0 (claudin-1-cellwall + 1 - (max list (NF-kB) (NO / 10))) set claudin-1-cytoplasm max list 0 (claudin-1-cytoplasm - 1) ] [set claudin-1-cytoplasm max list 0 (claudin-1-cytoplasm - 1) ] ifelse ZO-1-cytoplasm >= 40 [ifelse hours <= 12 [set ZO-1-cellwall max list 0 (ZO-1-cellwall + 1 - (NF-kB)) ] [set ZO-1-cellwall max list 0 (ZO-1-cellwall + 1 - (NO / 10)) ] set ZO-1-cytoplasm max list 0 (ZO-1-cytoplasm - 1) ] [set ZO-1-cytoplasm max list 0 (ZO-1-cytoplasm - 1) ] ifelse ZO-3-cytoplasm >= 40 [set ZO-3-cellwall max list 0 (ZO-3-cellwall + 1) set ZO-3-cytoplasm max list 0 (ZO-3-cytoplasm - 1) ] [set ZO-3-cytoplasm max list 0 (ZO-3-cytoplasm - 1) ] end to form-tight-junction set tight-junction occludin-cellwall + claudin-1-cellwall + ZO-1-cellwall + ZO-3-cellwall ; maximum value = 480 ifelse ((occludin-cellwall > 0) and (claudin-1-cellwall > 0) and (ZO-1-cellwall > 0) or (ZO-3-cellwall > 0)) [set sick 0] [set sick 1] ifelse sick = 1 [set breed epi-cell-sick] [set breed epi-cell-health] end to protein-breakdown set occludin-cellwall max list 0 (occludin-cellwall - 1) set claudin-1-cellwall max list 0 (claudin-1-cellwall - 1) set ZO-1-cellwall max list 0 (ZO-1-cellwall - 1) set ZO-3-cellwall max list 0 (ZO-3-cellwall - 1) end to sum-total-proteins set p-occludin occludin-cytoplasm set p-occludin-cellwall occludin-cellwall set p-claudin-1 claudin-1-cytoplasm set p-claudin-1-cellwall claudin-1-cellwall set p-ZO-1 ZO-1-cytoplasm set p-ZO-1-cellwall ZO-1-cellwall set p-ZO-3 ZO-3-cytoplasm set p-ZO-3-cellwall ZO-3-cellwall end to evaporate diffuse NO 0.05 diffuse cytomix 0.05 ask patches [ifelse NO-scavenger = true [ifelse hours < 12 [set NO NO * 0.99 ] [set NO NO - 0.0082 ] ] [set NO NO * 0.99 ] set cytomix cytomix * 0.9 if NO < 0.0001 [set NO 0 ] if cytomix < 0.0001 [set cytomix 0 ] ] end to data-collect if ( ( (hours = 12) or (hours = 24) or (hours = 48) ) and (step = 1) ) [ print hours print total-NO print total-solute-penetrated print (total-ZO-1 + total-ZO-1-cellwall) print (total-ZO-3 + total-ZO-3-cellwall) print (total-occludin + total-occludin-cellwall) print (total-claudin-1 + total-claudin-1-cellwall) print (total-iNOS) print (total-NF-kB) if hours = 48 [print " "] ] end to draw-graph set-current-plot "Solute-Permeability" set-current-plot-pen "Total-Solute-Lumen" plot total-solute-lumen set-current-plot-pen "Total-Solute-Penetrated" plot total-solute-penetrated set-current-plot "NO" set-current-plot-pen "NO" plot total-NO set-current-plot "Cytomix" set-current-plot-pen "Cytomix" plot total-cytomix set-current-plot "Total Claudin-1" set-current-plot-pen "Claudin-1" plot total-Claudin-1 set-current-plot "Total Occludin" set-current-plot-pen "Occludin" plot total-occludin set-current-plot "Total Occludin-cellwall" set-current-plot-pen "Occludin-cellwall" plot total-occludin-cellwall set-current-plot "Total ZO-1" set-current-plot-pen "ZO-1" plot total-ZO-1 set-current-plot "Total Claudin-1-cellwall" set-current-plot-pen "claudin-1-cellwall" plot total-claudin-1-cellwall set-current-plot "Total iNOS" set-current-plot-pen "iNOS" plot total-iNOS set-current-plot "Total NF-kB" set-current-plot-pen "NF-kB" plot total-NF-kB end @#$#@#$#@ GRAPHICS-WINDOW 339 10 685 377 10 10 16.0 1 10 1 1 1 0 1 1 1 CC-WINDOW 5 658 901 753 Command Center 0 BUTTON 11 10 77 43 Setup setup NIL 1 T OBSERVER T NIL SLIDER 147 79 319 112 Initial-NO Initial-NO 0 100 50 1 1 NIL SWITCH 8 104 111 137 Data Data 0 1 -1000 SWITCH 8 147 125 180 Loop-run Loop-run 1 1 -1000 BUTTON 12 52 75 85 Go Go T 1 T OBSERVER T NIL SLIDER 146 113 318 146 initial-cytomix initial-cytomix 0 100 50 1 1 NIL SLIDER 147 11 319 44 Mode Mode 0 5 0 1 1 NIL SLIDER 147 45 319 78 Diffusion-rate Diffusion-rate 0 0.5 0.05 0.01 1 NIL MONITOR 220 211 320 260 Solute-Lumen Total-solute-lumen 3 1 MONITOR 163 263 322 312 Solute-penetrated total-solute-penetrated 3 1 MONITOR 204 155 261 204 Step Step 3 1 MONITOR 264 156 321 205 Hours Hours 3 1 PLOT 695 12 890 167 Solute-Permeability Time Solute 0.0 400.0 0.0 25.0 true false PENS "Total-solute-penetrated" 1.0 0 -2064490 true "Total-solute-lumen" 1.0 0 -16777216 true PLOT 695 171 892 328 NO Time Level 0.0 400.0 0.0 100.0 true false PENS "NO" 1.0 0 -8630108 true PLOT 696 333 890 480 Total Claudin-1 Time Claudin-1 0.0 400.0 0.0 100.0 true false PENS "Claudin-1" 1.0 0 -16777216 true PLOT 301 380 496 507 Total Occludin Time Level 0.0 400.0 0.0 100.0 true false PENS "occludin" 1.0 0 -16777216 true PLOT 691 483 891 633 Cytomix Time Cytomix 0.0 400.0 0.0 50.0 true false PENS "default" 1.0 0 -13840069 true "Cytomix" 1.0 0 -10899396 true PLOT 496 378 688 508 Total Occludin-cellwall Time Protein 0.0 400.0 0.0 100.0 true false PENS "Occludin-cellwall" 1.0 0 -16777216 true PLOT 303 515 498 644 Total ZO-1 Time ZO-1 0.0 400.0 0.0 100.0 true false PENS "ZO-1" 1.0 0 -16777216 true SWITCH 8 191 117 224 Add-NO Add-NO 1 1 -1000 SWITCH 5 230 146 263 Add-Cytomix Add-Cytomix 0 1 -1000 PLOT 502 511 686 642 Total Claudin-1-cellwall Time Claudin-1-cellwall 0.0 400.0 0.0 100.0 true false PENS "claudin-1-cellwall" 1.0 0 -16777216 true SWITCH 4 265 151 298 NO-scavenger NO-scavenger 1 1 -1000 SLIDER 5 352 177 385 NAD+ NAD+ 0 0.1 0.0 0.1 1 NIL SLIDER 5 312 177 345 Ethyl-pyruvate Ethyl-pyruvate 0 0.1 0.0 0.1 1 NIL PLOT 93 387 293 507 Total iNOS Time iNOS 0.0 400.0 0.0 50.0 true false PENS "iNOS" 1.0 0 -16777216 true PLOT 92 517 292 637 Total NF-kB Time NF-kB 0.0 400.0 0.0 10.0 true false PENS "NF-kB" 1.0 0 -16777216 true @#$#@#$#@ WHAT IS IT? =========== Gut Epithelial Cell Barrier-Function Model This is an abstract model of Epithelial Cell barrier function. It is based on an epithelial cell culture model that looks at the effect of cellular tight junction status on permeability of the epithelial cell sheet. Each gridspace represents an epithelial cell that can exist in one of two states: "healthy" or "sick." "Healthy" cells have intact tight junctions represented by the yellow margin, "sick" cells have lost the tight junction proteins and have a black border. The agent rules present in an abstract form the sequence of synthesis of the proteins (and their precursors) that make up the tight junctions. In the "healthy" state (i.e. with tight junctions intact) the entire surface of epithelial cells is impermeable to the "solute." Cells transition between "healthy" and "sick" by interruption of tight junction protein synthesis. The primary mediator of this is nitric oxide (NO). NO interrupts the synthetic pathways for the tight junction proteins. NO can either be directly added to the model (via the "Add-NO" button), or be produced by the epithelial cells via inducible nitric oxide synthetase (iNOS) in response to addition of a mix of pro-inflammatory cytokines (via the "Add-Cytomix" button). The consequence of loss of tight junctions is that the areas of this loss become permeable to the "solute." This is a generic solute that, once the barrier becomes permeable, will diffuse through from a "lumen" "side" to a "penetrated" "side." The different "sides" of the epithelial cell barrier are represented by different patch variables, and can be seen by changing the "mode" by which the graphics screen scales it patch colors. The first graph reports the relative levels of the "lumen" and "penetrated" solute. The second graph reports the levels of NO and Cytomix over time. ARCHITECTURE AND INTERFACE -------------------------- 21 x 21 Grid of Epi Cells with Tight Junctions Agents are Epi Cells with 2 possible Shapes: "epi-cell-health" with intact TJs and "epi-cell-sick" with disrupted TJs 5 Proteins needed for TJ formation: 1) Occludin 2) Claudin-1 3) ZO-1 4) ZO-2 5) ZO-3 TJ breakdown if these proteins are not appropriately at the Epi Cell Periphery NO is a mediator for thw metabolism of the following proteins: 1) Decreases synthesis of ZO-1 mRNA, ZO-1, ZO-3, Occludin 2) Increases synthesis of Claudin-1 3) Impairs intracellular sublocalization of ZO-1, occludin and claudin-1 Treatment with pro-inflammatory cytokines (IL-1, TNF, INF-g = cytomix) activates iNOS and stimulates Epi Cell production of NO. Therefore all the above effects on TJ proteins are also seen with cytomix. Selective inhibition of iNOS reduces the effect of cytomix on permiability. iNOS function is dependent upon proper activation of iNOSmRNA. This will be activated by presence of Cytomix (value > 0.0001). This acts through NF-kB which in turn activates iNOSmRNA production. Ethyl pyruvate and NAD+ both inhibit the action of NF-kB. Furthermore, iNOSmRNA can be inhibited by ethyl pyruvate. The addition of these substances can be controlled with sliders on the interface. Timescales in paper are at 12, 24 and 48 hours. 1 step = 5 minutes 12 steps = 1 hour Buttons to turn on: 1) Data Collection function 2) Looped runs to generate an experimental population 3) Addition of NO donor 4) Addition of Cytomix 5) Addition of NO scavenger Sliders control: 1) Graphical Mode for display of different variables (See "How to use it") 2) Diffusion rate 3) Initial NO dose density 4) Initial Cytomix dose density 5) Degree of added Ethyl pyruvate 6) Degree of added NAD+ HOW TO USE IT ------------- The "Setup" button resets the model, but does not clear the output screen. The "Go" button runs the model. The "Add-NO" button provides a one-time random distribution of NO to the model. The "Add-Cytomix" button provides a one-time random distribution of Cytomix to the model. The "Data" switch turns on/off the collection of "solute-lumen" and "solute-penetrated" at 12, 24 and 48 hours. The "Loop-run" switch turns on/off the mode of multiple runs. The runs are set at 48 hours and can either be in "NO-Add" or "Cytomix-Add" (these determine whether the initial insult will be either NO or Cytomix). The "Mode" slider determines what variable the patches are scaled to: Mode=1: Shows Epithelial cells as either "healthy' or "sick" with focus on presence of tight junctions. Mode=2: Shows amount of solute-lumen present. Mode=3: Shows amount of solute-penetrated present. Mode=4: Shows amount and distribution of NO. Mode=5: Shows amount and distribution of Cytomix. The "Diffusion Rate" slider changes the rate at which the solute will travel across the permeable areas of the model. The "Initial NO" slider sets the amount of patches hit with NO. The "Initial Cytomix" slider set the amount of patches hit with Cytomix. THe "NO-scavenger" slider simulates the addition of a scavenger of NO, essentially removing NO from the affected areas. This reverses the protein synthesis blocking effect of NO. A value of "0" means no scavenger, a value of "1" adds it to the mix. The "NO-mode" slider chooses NO as the recurrent insult if "Loop-run" switch is on. The "Cytomix-mode" slider chooses Cytomix as the recurrent insult if "Loop-run" switch is on. The "Ethyl pyruvate" and "NAD+" sliders set the amount of ethyl pyruvate and NAD+ that is administered to the model. It affects the update of NF-kB and iNOSmRNA. To run the model: Press "Setup" Decide whether you want to run with incubation with NO ("Add-NO" swtich "On") or Cytomix ("Add-Cytomix" switch "On"). Choose whether you want to do looping runs ("Loop-run" switch) and/or whether you want to do data collection. Choose levels of "Diffusion rate," "Initial-NO," and "Initial-Cytomix." It is recommended that you start with Mode=1 to see the tight junction status. This slider can be changed on the fly, however, to see the distribution of the other variables. It is recommended that you leave the "NO-scavenger" slider to "0" at first. Press "Go" to run. THINGS TO NOTICE ---------------- The loss of tight junctions will have a random pattern corresponding to the intitial distribution of NO/Cytomix. If the model is allowed to run beyond 48 hours, or the initial insult number is low, you can see the recovery of the tight junctions as the proteins are re-synthesized after levels of NO drop. There will be a lag in tight junction loss if Cytmoix is used as the insult, accounting for the time it takes for iNOS to produce NO. Also notice the relative shapes of the NO and Cytmoix concentration curves in this situation. The different modes were primarily used for de-bugging purposes to make sure that the patch variables were behaving as intended, but can be interesting to watch. THINGS TO TRY ------------- You can adjust the various sliders to increase/decrease the initial insult/diffusion rate. You can, after the model is running, add the NO-scavenger to attenuate the effect of the NO/Cytomix. EXTENDING THE MODEL ------------------- As mentioned above, this is an abstract preliminary model. The rules for protein synthesis are very basic and work is being done to expand the scope of these rules. Additional activating/inhibiting variables may also be added. The model here is also in the process of being integrated with an endothelial model using Netlogo 3-d Preview to create a bi-layer simulation of gut tissue function. CREDITS ------- This model was produced by Gary An, MD from the Department of Trauma, Cook County Hospital, Chicago, IL, USA for a Poster presented at the 27th Annual Conference of the Shock Society, June 6, 2004: An G, Delude R. Agent based model of cell culture epithelial barrier function: Using computer simulation in conjunction with a basic science model. Shock 2004; 21S2:s13. Please email and questions or comments to docgca@earthlink.net @#$#@#$#@ default true 0 Polygon -7500403 true true 150 5 40 250 150 205 260 250 ant true 0 Polygon -7500403 true true 136 61 129 46 144 30 119 45 124 60 114 82 97 37 132 10 93 36 111 84 127 105 172 105 189 84 208 35 171 11 202 35 204 37 186 82 177 60 180 44 159 32 170 44 165 60 Polygon -7500403 true true 150 95 135 103 139 117 125 149 137 180 135 196 150 204 166 195 161 180 174 150 158 116 164 102 Polygon -7500403 true true 149 186 128 197 114 232 134 270 149 282 166 270 185 232 171 195 149 186 Polygon -7500403 true true 225 66 230 107 159 122 161 127 234 111 236 106 Polygon -7500403 true true 78 58 99 116 139 123 137 128 95 119 Polygon -7500403 true true 48 103 90 147 129 147 130 151 86 151 Polygon -7500403 true true 65 224 92 171 134 160 135 164 95 175 Polygon -7500403 true true 235 222 210 170 163 162 161 166 208 174 Polygon -7500403 true true 249 107 211 147 168 147 168 150 213 150 arrow true 0 Polygon -7500403 true true 150 0 0 150 105 150 105 293 195 293 195 150 300 150 bee true 0 Polygon -1184463 true false 152 149 77 163 67 195 67 211 74 234 85 252 100 264 116 276 134 286 151 300 167 285 182 278 206 260 220 242 226 218 226 195 222 166 Polygon -16777216 true false 150 149 128 151 114 151 98 145 80 122 80 103 81 83 95 67 117 58 141 54 151 53 177 55 195 66 207 82 211 94 211 116 204 139 189 149 171 152 Polygon -7500403 true true 151 54 119 59 96 60 81 50 78 39 87 25 103 18 115 23 121 13 150 1 180 14 189 23 197 17 210 19 222 30 222 44 212 57 192 58 Polygon -16777216 true false 70 185 74 171 223 172 224 186 Polygon -16777216 true false 67 211 71 226 224 226 225 211 67 211 Polygon -16777216 true false 91 257 106 269 195 269 211 255 Line -1 false 144 100 70 87 Line -1 false 70 87 45 87 Line -1 false 45 86 26 97 Line -1 false 26 96 22 115 Line -1 false 22 115 25 130 Line -1 false 26 131 37 141 Line -1 false 37 141 55 144 Line -1 false 55 143 143 101 Line -1 false 141 100 227 138 Line -1 false 227 138 241 137 Line -1 false 241 137 249 129 Line -1 false 249 129 254 110 Line -1 false 253 108 248 97 Line -1 false 249 95 235 82 Line -1 false 235 82 144 100 bird1 false 0 Polygon -7500403 true true 2 6 2 39 270 298 297 298 299 271 187 160 279 75 276 22 100 67 31 0 bird2 false 0 Polygon -7500403 true true 2 4 33 4 298 270 298 298 272 298 155 184 117 289 61 295 61 105 0 43 boat1 false 0 Polygon -1 true false 63 162 90 207 223 207 290 162 Rectangle -6459832 true false 150 32 157 162 Polygon -13345367 true false 150 34 131 49 145 47 147 48 149 49 Polygon -7500403 true true 158 33 230 157 182 150 169 151 157 156 Polygon -7500403 true true 149 55 88 143 103 139 111 136 117 139 126 145 130 147 139 147 146 146 149 55 boat2 false 0 Polygon -1 true false 63 162 90 207 223 207 290 162 Rectangle -6459832 true false 150 32 157 162 Polygon -13345367 true false 150 34 131 49 145 47 147 48 149 49 Polygon -7500403 true true 157 54 175 79 174 96 185 102 178 112 194 124 196 131 190 139 192 146 211 151 216 154 157 154 Polygon -7500403 true true 150 74 146 91 139 99 143 114 141 123 137 126 131 129 132 139 142 136 126 142 119 147 148 147 boat3 false 0 Polygon -1 true false 63 162 90 207 223 207 290 162 Rectangle -6459832 true false 150 32 157 162 Polygon -13345367 true false 150 34 131 49 145 47 147 48 149 49 Polygon -7500403 true true 158 37 172 45 188 59 202 79 217 109 220 130 218 147 204 156 158 156 161 142 170 123 170 102 169 88 165 62 Polygon -7500403 true true 149 66 142 78 139 96 141 111 146 139 148 147 110 147 113 131 118 106 126 71 box true 0 Polygon -7500403 true true 45 255 255 255 255 45 45 45 butterfly1 true 0 Polygon -16777216 true false 151 76 138 91 138 284 150 296 162 286 162 91 Polygon -7500403 true true 164 106 184 79 205 61 236 48 259 53 279 86 287 119 289 158 278 177 256 182 164 181 Polygon -7500403 true true 136 110 119 82 110 71 85 61 59 48 36 56 17 88 6 115 2 147 15 178 134 178 Polygon -7500403 true true 46 181 28 227 50 255 77 273 112 283 135 274 135 180 Polygon -7500403 true true 165 185 254 184 272 224 255 251 236 267 191 283 164 276 Line -7500403 true 167 47 159 82 Line -7500403 true 136 47 145 81 Circle -7500403 true true 165 45 8 Circle -7500403 true true 134 45 6 Circle -7500403 true true 133 44 7 Circle -7500403 true true 133 43 8 circle false 0 Circle -7500403 true true 35 35 230 epi-cell-shape-health false 0 Rectangle -2064490 true false 2 5 298 297 Rectangle -1184463 true false 3 0 300 33 Rectangle -1184463 true false 0 1 31 298 Rectangle -1184463 true false 199 273 298 273 Rectangle -1184463 true false 2 271 298 300 Rectangle -1184463 true false 267 2 300 297 epi-cell-shape-sick false 0 Rectangle -2064490 true false 14 19 286 285 link true 0 Line -7500403 true 150 0 150 300 link direction true 0 Line -7500403 true 150 150 30 225 Line -7500403 true 150 150 270 225 person false 0 Circle -7500403 true true 155 20 63 Rectangle -7500403 true true 158 79 217 164 Polygon -7500403 true true 158 81 110 129 131 143 158 109 165 110 Polygon -7500403 true true 216 83 267 123 248 143 215 107 Polygon -7500403 true true 167 163 145 234 183 234 183 163 Polygon -7500403 true true 195 163 195 233 227 233 206 159 sheep false 15 Rectangle -1 true true 90 75 270 225 Circle -1 true true 15 75 150 Rectangle -16777216 true false 81 225 134 286 Rectangle -16777216 true false 180 225 238 285 Circle -16777216 true false 1 88 92 spacecraft true 0 Polygon -7500403 true true 150 0 180 135 255 255 225 240 150 180 75 240 45 255 120 135 thin-arrow true 0 Polygon -7500403 true true 150 0 0 150 120 150 120 293 180 293 180 150 300 150 truck-down false 0 Polygon -7500403 true true 225 30 225 270 120 270 105 210 60 180 45 30 105 60 105 30 Polygon -8630108 true false 195 75 195 120 240 120 240 75 Polygon -8630108 true false 195 225 195 180 240 180 240 225 truck-left false 0 Polygon -7500403 true true 120 135 225 135 225 210 75 210 75 165 105 165 Polygon -8630108 true false 90 210 105 225 120 210 Polygon -8630108 true false 180 210 195 225 210 210 truck-right false 0 Polygon -7500403 true true 180 135 75 135 75 210 225 210 225 165 195 165 Polygon -8630108 true false 210 210 195 225 180 210 Polygon -8630108 true false 120 210 105 225 90 210 turtle true 0 Polygon -7500403 true true 138 75 162 75 165 105 225 105 225 142 195 135 195 187 225 195 225 225 195 217 195 202 105 202 105 217 75 225 75 195 105 187 105 135 75 142 75 105 135 105 wolf false 0 Rectangle -7500403 true true 15 105 105 165 Rectangle -7500403 true true 45 90 105 105 Polygon -7500403 true true 60 90 83 44 104 90 Polygon -16777216 true false 67 90 82 59 97 89 Rectangle -1 true false 48 93 59 105 Rectangle -16777216 true false 51 96 55 101 Rectangle -16777216 true false 0 121 15 135 Rectangle -16777216 true false 15 136 60 151 Polygon -1 true false 15 136 23 149 31 136 Polygon -1 true false 30 151 37 136 43 151 Rectangle -7500403 true true 105 120 263 195 Rectangle -7500403 true true 108 195 259 201 Rectangle -7500403 true true 114 201 252 210 Rectangle -7500403 true true 120 210 243 214 Rectangle -7500403 true true 115 114 255 120 Rectangle -7500403 true true 128 108 248 114 Rectangle -7500403 true true 150 105 225 108 Rectangle -7500403 true true 132 214 155 270 Rectangle -7500403 true true 110 260 132 270 Rectangle -7500403 true true 210 214 232 270 Rectangle -7500403 true true 189 260 210 270 Line -7500403 true 263 127 281 155 Line -7500403 true 281 155 281 192 wolf-left false 3 Polygon -6459832 true true 117 97 91 74 66 74 60 85 36 85 38 92 44 97 62 97 81 117 84 134 92 147 109 152 136 144 174 144 174 103 143 103 134 97 Polygon -6459832 true true 87 80 79 55 76 79 Polygon -6459832 true true 81 75 70 58 73 82 Polygon -6459832 true true 99 131 76 152 76 163 96 182 104 182 109 173 102 167 99 173 87 159 104 140 Polygon -6459832 true true 107 138 107 186 98 190 99 196 112 196 115 190 Polygon -6459832 true true 116 140 114 189 105 137 Rectangle -6459832 true true 109 150 114 192 Rectangle -6459832 true true 111 143 116 191 Polygon -6459832 true true 168 106 184 98 205 98 218 115 218 137 186 164 196 176 195 194 178 195 178 183 188 183 169 164 173 144 Polygon -6459832 true true 207 140 200 163 206 175 207 192 193 189 192 177 198 176 185 150 Polygon -6459832 true true 214 134 203 168 192 148 Polygon -6459832 true true 204 151 203 176 193 148 Polygon -6459832 true true 207 103 221 98 236 101 243 115 243 128 256 142 239 143 233 133 225 115 214 114 wolf-right false 3 Polygon -6459832 true true 170 127 200 93 231 93 237 103 262 103 261 113 253 119 231 119 215 143 213 160 208 173 189 187 169 190 154 190 126 180 106 171 72 171 73 126 122 126 144 123 159 123 Polygon -6459832 true true 201 99 214 69 215 99 Polygon -6459832 true true 207 98 223 71 220 101 Polygon -6459832 true true 184 172 189 234 203 238 203 246 187 247 180 239 171 180 Polygon -6459832 true true 197 174 204 220 218 224 219 234 201 232 195 225 179 179 Polygon -6459832 true true 78 167 95 187 95 208 79 220 92 234 98 235 100 249 81 246 76 241 61 212 65 195 52 170 45 150 44 128 55 121 69 121 81 135 Polygon -6459832 true true 48 143 58 141 Polygon -6459832 true true 46 136 68 137 Polygon -6459832 true true 45 129 35 142 37 159 53 192 47 210 62 238 80 237 Line -16777216 false 74 237 59 213 Line -16777216 false 59 213 59 212 Line -16777216 false 58 211 67 192 Polygon -6459832 true true 38 138 66 149 Polygon -6459832 true true 46 128 33 120 21 118 11 123 3 138 5 160 13 178 9 192 0 199 20 196 25 179 24 161 25 148 45 140 Polygon -6459832 true true 67 122 96 126 63 144 @#$#@#$#@ NetLogo 3.0.2 @#$#@#$#@ @#$#@#$#@ @#$#@#$#@ @#$#@#$#@