/**
  * Show the form for editing the specified resource.
  *
  * @param  int  $id
  * @return Response
  */
 public function publish($slug)
 {
     $category = PublicationCategory::find($slug);
     $category->update(['is_published' => $category->is_published ? 0 : 1]);
     return Redirect::route('publications-categories.admin');
 }