#include <bits/stdc++.h>
std::string checkIfItCanBeConvertedIntoAPalindrome(std::string str) {
  for (int i = 0; i < str.length() / 2; i++) {
    char charA = str[i];
    char charB = str[str.length() - i - 1];
    if (charA - 1 == charB - 1 || charA - 1 == charB + 1 ||
        charA + 1 == charB - 1 || charA + 1 == charB - 1)
      ;
    else
      return "NO";
  }
  return "YES";
}
int main() {
  int n;
  std::cin >> n;
  std::vector<std::string> l(n);
  int i = 0;
  while (i < n) {
    int x;
    std::cin >> x;
    std::string str;
    std::cin >> str;
    l[i] = checkIfItCanBeConvertedIntoAPalindrome(str);
    i++;
  }
  for (auto s : l) {
    std::cout << s << "\n";
  }
  return 0;
}
