Top Leading Issues Top Leading Issues en Copyright 2015 ProQuest LLC. All rights reserved. 03/01/2015 03/01/2015 SIRS 90 46 Knowledge Source Climatic changes &title=Climatic changes Climatic changes 0000005047 Animal experimentation &title=Animal experimentation Animal experimentation 0000001245 Gun control &title=Gun control Gun control 0000011611 Homework &title=Homework Homework 0000012354 Cellular telephones &title=Cellular telephones Cellular telephones 0000004158 Zoos &title=Zoos Zoos 0000029268 Marijuana, Law and legislation &title=Marijuana, Law and legislation Marijuana, Law and legislation 0000015900 Abortion &title=Abortion Abortion 0000000037 Same-sex marriage &title=Same-sex marriage Same-sex marriage 0000010818 Attention-deficit hyperactivity disorder &title=Attention-deficit hyperactivity disorder Attention-deficit hyperactivity disorder 0000002040