diff --git a/examples/medication_prescription.n3s b/examples/medication_prescription.n3s
index fad8901..581ea23 100644
--- a/examples/medication_prescription.n3s
+++ b/examples/medication_prescription.n3s
@@ -3,7 +3,7 @@
 # -----------------------
 
 @prefix log: <http://www.w3.org/2000/10/swap/log#>.
-@prefix : <urn:example:>.
+@prefix : <https://example.org/ns#> .
 
 # patient Ann
 :Ann :has :Fever.
@@ -69,14 +69,3 @@
         _:WHO :isPrescribed :betaBlocker.
     }.
 }.
-
-# query
-() log:onNegativeSurface {
-    :Ann :isPrescribed :aspirinHighDose.
-    :Joe :isPrescribed :betaBlocker.
-    () log:onNegativeAnswerSurface {
-        :Ann :isPrescribed :aspirinHighDose.
-        :Joe :isPrescribed :betaBlocker.
-        :test :is true.
-    }.
-}.