#include <bits/stdc++.h>
using namespace std;
int main() {
  int t, n, i, j;
  cin >> t;
  string s;
  while (t--) {
    cin >> n;
    cin >> s;
    j = n - 1;
    for (i = 0; i < (n / 2); i++) {
      int a = s[i], b = s[j];
      if (!(a == b || abs(a - b) == 2)) break;
      j--;
    }
    if (i == n / 2)
      cout << "YES\n";
    else
      cout << "NO\n";
  }
  return 0;
}
