Exclude Posts in a Given Category

Check if the array contains a category not tested live but is valid PHP

    <?php
    $myquery['tax_query'] = array(
    'relation' => 'OR',

      array(
        'taxonomy' => 'category',
        'category__not_in' => array('explore'),
        'field' => 'slug',  
      ),
      array(
        'taxonomy' => 'category',
        'terms' => array('outdoor-recreation'),
        'field' => 'slug',  
    ),
    array(
        'taxonomy' => 'take_category',
        'terms' => array('outdoor-recreation'),
        'field' => 'slug',
    ),
     array(
        'taxonomy' => 'story_category',
        'terms' => array('outdoor-recreation'),
        'field' => 'slug',
      ),
      array(
         'taxonomy' => 'news_category',
        'terms' => array('outdoor-recreation'),
        'field' => 'slug',
       ),

     );
     $myquery['showposts'] = 1;

     query_posts($myquery);

    while( $wp_query->have_posts() ) :
    $wp_query->the_post();

    // Get post id
    $post_id = get_the_ID();
    // Check categories of post
    $categories = get_the_category($post_id);
    if (in_array("explore", $categories)) {
      // explore is in the array
    }
    else{
     // Not in array do something 
    }
    endwhile;
  wp_reset_query();
     ?>