[0] 0.3.207.216.in-addr.arpa.: domain name does not exist
[0] 1.3.207.216.in-addr.arpa.: domain name does not exist
[86400] 2.3.207.216.in-addr.arpa. domain name pointer firewall.premsys.com
[86400] 3.3.207.216.in-addr.arpa. domain name pointer ns1.premsys.com
[86400] 4.3.207.216.in-addr.arpa. domain name pointer ns2.premsys.com
[0] 5.3.207.216.in-addr.arpa.: domain name does not exist
[86400] 6.3.207.216.in-addr.arpa. domain name pointer mail.premsys.com
[0] 7.3.207.216.in-addr.arpa.: domain name does not exist
[86400] 8.3.207.216.in-addr.arpa. domain name pointer dom400.premsys.com
[0] 9.3.207.216.in-addr.arpa.: domain name does not exist
[0] 10.3.207.216.in-addr.arpa.: domain name does not exist
[0] 11.3.207.216.in-addr.arpa.: domain name does not exist
[0] 12.3.207.216.in-addr.arpa.: domain name does not exist
[0] 13.3.207.216.in-addr.arpa.: domain name does not exist
[0] 14.3.207.216.in-addr.arpa.: domain name does not exist
[0] 15.3.207.216.in-addr.arpa.: domain name does not exist
[0] 16.3.207.216.in-addr.arpa.: domain name does not exist
[0] 17.3.207.216.in-addr.arpa.: domain name does not exist
[0] 18.3.207.216.in-addr.arpa.: domain name does not exist
[0] 19.3.207.216.in-addr.arpa.: domain name does not exist
[0] 20.3.207.216.in-addr.arpa.: domain name does not exist
[0] 21.3.207.216.in-addr.arpa.: domain name does not exist
[0] 22.3.207.216.in-addr.arpa.: domain name does not exist
[0] 23.3.207.216.in-addr.arpa.: domain name does not exist
[0] 24.3.207.216.in-addr.arpa.: domain name does not exist
[0] 25.3.207.216.in-addr.arpa.: domain name does not exist
[0] 26.3.207.216.in-addr.arpa.: domain name does not exist
[0] 27.3.207.216.in-addr.arpa.: domain name does not exist
[0] 28.3.207.216.in-addr.arpa.: domain name does not exist
[0] 29.3.207.216.in-addr.arpa.: domain name does not exist
[0] 30.3.207.216.in-addr.arpa.: domain name does not exist
[0] 31.3.207.216.in-addr.arpa.: domain name does not exist
[0] 32.3.207.216.in-addr.arpa.: domain name does not exist
[0] 33.3.207.216.in-addr.arpa.: domain name does not exist
[0] 34.3.207.216.in-addr.arpa.: domain name does not exist
[0] 35.3.207.216.in-addr.arpa.: domain name does not exist
[0] 36.3.207.216.in-addr.arpa.: domain name does not exist
[0] 37.3.207.216.in-addr.arpa.: domain name does not exist
[0] 38.3.207.216.in-addr.arpa.: domain name does not exist
[0] 39.3.207.216.in-addr.arpa.: domain name does not exist
[0] 40.3.207.216.in-addr.arpa.: domain name does not exist
[0] 41.3.207.216.in-addr.arpa.: domain name does not exist
[0] 42.3.207.216.in-addr.arpa.: domain name does not exist
[0] 43.3.207.216.in-addr.arpa.: domain name does not exist
[0] 44.3.207.216.in-addr.arpa.: domain name does not exist
[0] 45.3.207.216.in-addr.arpa.: domain name does not exist
[0] 46.3.207.216.in-addr.arpa.: domain name does not exist
[0] 47.3.207.216.in-addr.arpa.: domain name does not exist
[86400] 48.3.207.216.in-addr.arpa. domain name pointer 216-207-3-48.dia.static.qwest.net
[86400] 49.3.207.216.in-addr.arpa. domain name pointer 216-207-3-49.dia.static.qwest.net
[86400] 50.3.207.216.in-addr.arpa. domain name pointer 216-207-3-50.dia.static.qwest.net
[86400] 51.3.207.216.in-addr.arpa. domain name pointer 216-207-3-51.dia.static.qwest.net
[86400] 52.3.207.216.in-addr.arpa. domain name pointer 216-207-3-52.dia.static.qwest.net
[86400] 53.3.207.216.in-addr.arpa. domain name pointer 216-207-3-53.dia.static.qwest.net
[86400] 54.3.207.216.in-addr.arpa. domain name pointer 216-207-3-54.dia.static.qwest.net
[86400] 55.3.207.216.in-addr.arpa. domain name pointer 216-207-3-55.dia.static.qwest.net
[86400] 56.3.207.216.in-addr.arpa. domain name pointer 216-207-3-56.dia.static.qwest.net
[86400] 57.3.207.216.in-addr.arpa. domain name pointer 216-207-3-57.dia.static.qwest.net
[86400] 58.3.207.216.in-addr.arpa. domain name pointer 216-207-3-58.dia.static.qwest.net
[86400] 59.3.207.216.in-addr.arpa. domain name pointer 216-207-3-59.dia.static.qwest.net
[86400] 60.3.207.216.in-addr.arpa. domain name pointer 216-207-3-60.dia.static.qwest.net
[86400] 61.3.207.216.in-addr.arpa. domain name pointer 216-207-3-61.dia.static.qwest.net
[86400] 62.3.207.216.in-addr.arpa. domain name pointer 216-207-3-62.dia.static.qwest.net
[86400] 63.3.207.216.in-addr.arpa. domain name pointer 216-207-3-63.dia.static.qwest.net
[86400] 64.3.207.216.in-addr.arpa. domain name pointer 216-207-3-64.dia.static.qwest.net
[86400] 65.3.207.216.in-addr.arpa. domain name pointer 216-207-3-65.dia.static.qwest.net
[86400] 66.3.207.216.in-addr.arpa. domain name pointer 216-207-3-66.dia.static.qwest.net
[86400] 67.3.207.216.in-addr.arpa. domain name pointer zenwise.alexian.net
[86400] 68.3.207.216.in-addr.arpa. domain name pointer alexianresults.net
[86400] 69.3.207.216.in-addr.arpa. domain name pointer 216-207-3-69.dia.static.qwest.net
[86400] 70.3.207.216.in-addr.arpa. domain name pointer www.alexian.net
[86400] 71.3.207.216.in-addr.arpa. domain name pointer 216-207-3-71.dia.static.qwest.net
[86400] 72.3.207.216.in-addr.arpa. domain name pointer 216-207-3-72.dia.static.qwest.net
[86400] 73.3.207.216.in-addr.arpa. domain name pointer 216-207-3-73.dia.static.qwest.net
[86400] 74.3.207.216.in-addr.arpa. domain name pointer 216-207-3-74.dia.static.qwest.net
[86400] 75.3.207.216.in-addr.arpa. domain name pointer 216-207-3-75.dia.static.qwest.net
[86400] 76.3.207.216.in-addr.arpa. domain name pointer 216-207-3-76.dia.static.qwest.net
[86400] 77.3.207.216.in-addr.arpa. domain name pointer 216-207-3-77.dia.static.qwest.net
[86400] 78.3.207.216.in-addr.arpa. domain name pointer 216-207-3-78.dia.static.qwest.net
[86400] 79.3.207.216.in-addr.arpa. domain name pointer 216-207-3-79.dia.static.qwest.net
[86400] 80.3.207.216.in-addr.arpa. domain name pointer 216-207-3-80.dia.static.qwest.net
[86400] 81.3.207.216.in-addr.arpa. domain name pointer 216-207-3-81.dia.static.qwest.net
[86400] 82.3.207.216.in-addr.arpa. domain name pointer 216-207-3-82.dia.static.qwest.net
[86400] 83.3.207.216.in-addr.arpa. domain name pointer 216-207-3-83.dia.static.qwest.net
[86400] 84.3.207.216.in-addr.arpa. domain name pointer 216-207-3-84.dia.static.qwest.net
[86400] 85.3.207.216.in-addr.arpa. domain name pointer 216-207-3-85.dia.static.qwest.net
[86400] 86.3.207.216.in-addr.arpa. domain name pointer www.alexiweb.alexian.net
[86400] 87.3.207.216.in-addr.arpa. domain name pointer alexinet.org
[86400] 88.3.207.216.in-addr.arpa. domain name pointer diag.alexinet.org
[86400] 89.3.207.216.in-addr.arpa. domain name pointer cath.alexinet.org
[86400] 90.3.207.216.in-addr.arpa. domain name pointer alexicorp1.alexian.net
[86400] 91.3.207.216.in-addr.arpa. domain name pointer 216-207-3-91.dia.static.qwest.net
[86400] 92.3.207.216.in-addr.arpa. domain name pointer 216-207-3-92.dia.static.qwest.net
[86400] 93.3.207.216.in-addr.arpa. domain name pointer 216-207-3-93.dia.static.qwest.net
[86400] 94.3.207.216.in-addr.arpa. domain name pointer 216-207-3-94.dia.static.qwest.net
[86400] 95.3.207.216.in-addr.arpa. domain name pointer 216-207-3-95.dia.static.qwest.net
[86400] 96.3.207.216.in-addr.arpa. domain name pointer 216-207-3-96.dia.static.qwest.net
[86400] 97.3.207.216.in-addr.arpa. domain name pointer 216-207-3-97.dia.static.qwest.net
[86400] 98.3.207.216.in-addr.arpa. domain name pointer 216-207-3-98.dia.static.qwest.net
[86400] 99.3.207.216.in-addr.arpa. domain name pointer 216-207-3-99.dia.static.qwest.net
[86400] 100.3.207.216.in-addr.arpa. domain name pointer 216-207-3-100.dia.static.qwest.net
[86400] 101.3.207.216.in-addr.arpa. domain name pointer 216-207-3-101.dia.static.qwest.net
[86400] 102.3.207.216.in-addr.arpa. domain name pointer 216-207-3-102.dia.static.qwest.net
[86400] 103.3.207.216.in-addr.arpa. domain name pointer 216-207-3-103.dia.static.qwest.net
[86400] 104.3.207.216.in-addr.arpa. domain name pointer 216-207-3-104.dia.static.qwest.net
[86400] 105.3.207.216.in-addr.arpa. domain name pointer 216-207-3-105.dia.static.qwest.net
[86400] 106.3.207.216.in-addr.arpa. domain name pointer 216-207-3-106.dia.static.qwest.net
[86400] 107.3.207.216.in-addr.arpa. domain name pointer 216-207-3-107.dia.static.qwest.net
[86400] 108.3.207.216.in-addr.arpa. domain name pointer 216-207-3-108.dia.static.qwest.net
[86400] 109.3.207.216.in-addr.arpa. domain name pointer 216-207-3-109.dia.static.qwest.net
[86400] 110.3.207.216.in-addr.arpa. domain name pointer 216-207-3-110.dia.static.qwest.net
[86400] 111.3.207.216.in-addr.arpa. domain name pointer 216-207-3-111.dia.static.qwest.net mail.dwigans.com
[86400] 112.3.207.216.in-addr.arpa. domain name pointer 216-207-3-112.dia.static.qwest.net
[86400] 113.3.207.216.in-addr.arpa. domain name pointer 216-207-3-113.dia.static.qwest.net
[86400] 114.3.207.216.in-addr.arpa. domain name pointer 216-207-3-114.dia.static.qwest.net
[86400] 115.3.207.216.in-addr.arpa. domain name pointer 216-207-3-115.dia.static.qwest.net
[86400] 116.3.207.216.in-addr.arpa. domain name pointer 216-207-3-116.dia.static.qwest.net
[86400] 117.3.207.216.in-addr.arpa. domain name pointer 216-207-3-117.dia.static.qwest.net
[86400] 118.3.207.216.in-addr.arpa. domain name pointer 216-207-3-118.dia.static.qwest.net
[86400] 119.3.207.216.in-addr.arpa. domain name pointer 216-207-3-119.dia.static.qwest.net
[86400] 120.3.207.216.in-addr.arpa. domain name pointer 216-207-3-120.dia.static.qwest.net
[86400] 121.3.207.216.in-addr.arpa. domain name pointer 216-207-3-121.dia.static.qwest.net
[86400] 122.3.207.216.in-addr.arpa. domain name pointer 216-207-3-122.dia.static.qwest.net
[86400] 123.3.207.216.in-addr.arpa. domain name pointer 216-207-3-123.dia.static.qwest.net
[86400] 124.3.207.216.in-addr.arpa. domain name pointer 216-207-3-124.dia.static.qwest.net
[86400] 125.3.207.216.in-addr.arpa. domain name pointer 216-207-3-125.dia.static.qwest.net
[86400] 126.3.207.216.in-addr.arpa. domain name pointer 216-207-3-126.dia.static.qwest.net
[86400] 127.3.207.216.in-addr.arpa. domain name pointer 216-207-3-127.dia.static.qwest.net
[86400] 128.3.207.216.in-addr.arpa. domain name pointer 216-207-3-128.dia.static.qwest.net
[86400] 129.3.207.216.in-addr.arpa. domain name pointer 216-207-3-129.dia.static.qwest.net
[86400] 130.3.207.216.in-addr.arpa. domain name pointer 216-207-3-130.dia.static.qwest.net
[86400] 131.3.207.216.in-addr.arpa. domain name pointer 216-207-3-131.dia.static.qwest.net
[86400] 132.3.207.216.in-addr.arpa. domain name pointer 216-207-3-132.dia.static.qwest.net
[86400] 133.3.207.216.in-addr.arpa. domain name pointer 216-207-3-133.dia.static.qwest.net
[86400] 134.3.207.216.in-addr.arpa. domain name pointer 216-207-3-134.dia.static.qwest.net
[86400] 135.3.207.216.in-addr.arpa. domain name pointer 216-207-3-135.dia.static.qwest.net
[86400] 136.3.207.216.in-addr.arpa. domain name pointer 216-207-3-136.dia.static.qwest.net
[86400] 137.3.207.216.in-addr.arpa. domain name pointer 216-207-3-137.dia.static.qwest.net
[86400] 138.3.207.216.in-addr.arpa. domain name pointer 216-207-3-138.dia.static.qwest.net
[86400] 139.3.207.216.in-addr.arpa. domain name pointer 216-207-3-139.dia.static.qwest.net
[86400] 140.3.207.216.in-addr.arpa. domain name pointer 216-207-3-140.dia.static.qwest.net
[86400] 141.3.207.216.in-addr.arpa. domain name pointer 216-207-3-141.dia.static.qwest.net
[86400] 142.3.207.216.in-addr.arpa. domain name pointer 216-207-3-142.dia.static.qwest.net
[86400] 143.3.207.216.in-addr.arpa. domain name pointer 216-207-3-143.dia.static.qwest.net
[86400] 144.3.207.216.in-addr.arpa. domain name pointer 216-207-3-144.dia.static.qwest.net
[86400] 145.3.207.216.in-addr.arpa. domain name pointer 216-207-3-145.dia.static.qwest.net
[86400] 146.3.207.216.in-addr.arpa. domain name pointer 216-207-3-146.dia.static.qwest.net
[86400] 147.3.207.216.in-addr.arpa. domain name pointer 216-207-3-147.dia.static.qwest.net
[86400] 148.3.207.216.in-addr.arpa. domain name pointer 216-207-3-148.dia.static.qwest.net
[86400] 149.3.207.216.in-addr.arpa. domain name pointer 216-207-3-149.dia.static.qwest.net
[86400] 150.3.207.216.in-addr.arpa. domain name pointer 216-207-3-150.dia.static.qwest.net
[86400] 151.3.207.216.in-addr.arpa. domain name pointer 216-207-3-151.dia.static.qwest.net
[86400] 152.3.207.216.in-addr.arpa. domain name pointer 216-207-3-152.dia.static.qwest.net
[86400] 153.3.207.216.in-addr.arpa. domain name pointer 216-207-3-153.dia.static.qwest.net
[86400] 154.3.207.216.in-addr.arpa. domain name pointer 216-207-3-154.dia.static.qwest.net
[86400] 155.3.207.216.in-addr.arpa. domain name pointer 216-207-3-155.dia.static.qwest.net
[86400] 156.3.207.216.in-addr.arpa. domain name pointer 216-207-3-156.dia.static.qwest.net
[86400] 157.3.207.216.in-addr.arpa. domain name pointer 216-207-3-157.dia.static.qwest.net
[86400] 158.3.207.216.in-addr.arpa. domain name pointer 216-207-3-158.dia.static.qwest.net
[86400] 159.3.207.216.in-addr.arpa. domain name pointer 216-207-3-159.dia.static.qwest.net
[0] 160.3.207.216.in-addr.arpa.: domain name does not exist
[0] 161.3.207.216.in-addr.arpa.: domain name does not exist
[86400] 162.3.207.216.in-addr.arpa. domain name pointer mail.daubert.com
[0] 163.3.207.216.in-addr.arpa.: domain name does not exist
[0] 164.3.207.216.in-addr.arpa.: domain name does not exist
[0] 165.3.207.216.in-addr.arpa.: domain name does not exist
[0] 166.3.207.216.in-addr.arpa.: domain name does not exist
[0] 167.3.207.216.in-addr.arpa.: domain name does not exist
[0] 168.3.207.216.in-addr.arpa.: domain name does not exist
[0] 169.3.207.216.in-addr.arpa.: domain name does not exist
[0] 170.3.207.216.in-addr.arpa.: domain name does not exist
[0] 171.3.207.216.in-addr.arpa.: domain name does not exist
[0] 172.3.207.216.in-addr.arpa.: domain name does not exist
[0] 173.3.207.216.in-addr.arpa.: domain name does not exist
[0] 174.3.207.216.in-addr.arpa.: domain name does not exist
[0] 175.3.207.216.in-addr.arpa.: domain name does not exist
[0] 176.3.207.216.in-addr.arpa.: domain name does not exist
[0] 177.3.207.216.in-addr.arpa.: domain name does not exist
[0] 178.3.207.216.in-addr.arpa.: domain name does not exist
[0] 179.3.207.216.in-addr.arpa.: domain name does not exist
[0] 180.3.207.216.in-addr.arpa.: domain name does not exist
[0] 181.3.207.216.in-addr.arpa.: domain name does not exist
[0] 182.3.207.216.in-addr.arpa.: domain name does not exist
[0] 183.3.207.216.in-addr.arpa.: domain name does not exist
[0] 184.3.207.216.in-addr.arpa.: domain name does not exist
[0] 185.3.207.216.in-addr.arpa.: domain name does not exist
[0] 186.3.207.216.in-addr.arpa.: domain name does not exist
[0] 187.3.207.216.in-addr.arpa.: domain name does not exist
[0] 188.3.207.216.in-addr.arpa.: domain name does not exist
[0] 189.3.207.216.in-addr.arpa.: domain name does not exist
[0] 190.3.207.216.in-addr.arpa.: domain name does not exist
[0] 191.3.207.216.in-addr.arpa.: domain name does not exist
[86400] 192.3.207.216.in-addr.arpa. domain name pointer 216-207-3-192.dia.static.qwest.net
[86400] 193.3.207.216.in-addr.arpa. domain name pointer 216-207-3-193.dia.static.qwest.net
[86400] 194.3.207.216.in-addr.arpa. domain name pointer 216-207-3-194.dia.static.qwest.net
[86400] 195.3.207.216.in-addr.arpa. domain name pointer 216-207-3-195.dia.static.qwest.net
[86400] 196.3.207.216.in-addr.arpa. domain name pointer mail.longerlifeproducts.com
[86400] 197.3.207.216.in-addr.arpa. domain name pointer 216-207-3-197.dia.static.qwest.net
[86400] 198.3.207.216.in-addr.arpa. domain name pointer 216-207-3-198.dia.static.qwest.net
[86400] 199.3.207.216.in-addr.arpa. domain name pointer 216-207-3-199.dia.static.qwest.net
[86400] 200.3.207.216.in-addr.arpa. domain name pointer 216-207-3-200.dia.static.qwest.net
[86400] 201.3.207.216.in-addr.arpa. domain name pointer 216-207-3-201.dia.static.qwest.net
[86400] 202.3.207.216.in-addr.arpa. domain name pointer 216-207-3-202.dia.static.qwest.net
[86400] 203.3.207.216.in-addr.arpa. domain name pointer 216-207-3-203.dia.static.qwest.net
[86400] 204.3.207.216.in-addr.arpa. domain name pointer 216-207-3-204.dia.static.qwest.net
[86400] 205.3.207.216.in-addr.arpa. domain name pointer 216-207-3-205.dia.static.qwest.net
[86400] 206.3.207.216.in-addr.arpa. domain name pointer 216-207-3-206.dia.static.qwest.net
[86400] 207.3.207.216.in-addr.arpa. domain name pointer 216-207-3-207.dia.static.qwest.net
[86400] 208.3.207.216.in-addr.arpa. domain name pointer 216-207-3-208.dia.static.qwest.net
[86400] 209.3.207.216.in-addr.arpa. domain name pointer 216-207-3-209.dia.static.qwest.net
[86400] 210.3.207.216.in-addr.arpa. domain name pointer 216-207-3-210.dia.static.qwest.net
[86400] 211.3.207.216.in-addr.arpa. domain name pointer 216-207-3-211.dia.static.qwest.net
[86400] 212.3.207.216.in-addr.arpa. domain name pointer 216-207-3-212.dia.static.qwest.net
[86400] 213.3.207.216.in-addr.arpa. domain name pointer 216-207-3-213.dia.static.qwest.net
[86400] 214.3.207.216.in-addr.arpa. domain name pointer 216-207-3-214.dia.static.qwest.net
[86400] 215.3.207.216.in-addr.arpa. domain name pointer 216-207-3-215.dia.static.qwest.net
[86400] 216.3.207.216.in-addr.arpa. domain name pointer 216-207-3-216.dia.static.qwest.net
[86400] 217.3.207.216.in-addr.arpa. domain name pointer 216-207-3-217.dia.static.qwest.net
[86400] 218.3.207.216.in-addr.arpa. domain name pointer 216-207-3-218.dia.static.qwest.net
[86400] 219.3.207.216.in-addr.arpa. domain name pointer 216-207-3-219.dia.static.qwest.net
[86400] 220.3.207.216.in-addr.arpa. domain name pointer 216-207-3-220.dia.static.qwest.net
[86400] 221.3.207.216.in-addr.arpa. domain name pointer 216-207-3-221.dia.static.qwest.net
[86400] 222.3.207.216.in-addr.arpa. domain name pointer 216-207-3-222.dia.static.qwest.net
[86400] 223.3.207.216.in-addr.arpa. domain name pointer 216-207-3-223.dia.static.qwest.net
[0] 224.3.207.216.in-addr.arpa.: domain name does not exist
[0] 225.3.207.216.in-addr.arpa.: domain name does not exist
[0] 226.3.207.216.in-addr.arpa.: domain name does not exist
[0] 227.3.207.216.in-addr.arpa.: domain name does not exist
[0] 228.3.207.216.in-addr.arpa.: domain name does not exist
[0] 229.3.207.216.in-addr.arpa.: domain name does not exist
[0] 230.3.207.216.in-addr.arpa.: domain name does not exist
[0] 231.3.207.216.in-addr.arpa.: domain name does not exist
[0] 232.3.207.216.in-addr.arpa.: domain name does not exist
[0] 233.3.207.216.in-addr.arpa.: domain name does not exist
[0] 234.3.207.216.in-addr.arpa.: domain name does not exist
[0] 235.3.207.216.in-addr.arpa.: domain name does not exist
[0] 236.3.207.216.in-addr.arpa.: domain name does not exist
[0] 237.3.207.216.in-addr.arpa.: domain name does not exist
[0] 238.3.207.216.in-addr.arpa.: domain name does not exist
[0] 239.3.207.216.in-addr.arpa.: domain name does not exist
[0] 240.3.207.216.in-addr.arpa.: domain name does not exist
[0] 241.3.207.216.in-addr.arpa.: domain name does not exist
[0] 242.3.207.216.in-addr.arpa.: domain name does not exist
[0] 243.3.207.216.in-addr.arpa.: domain name does not exist
[0] 244.3.207.216.in-addr.arpa.: domain name does not exist
[0] 245.3.207.216.in-addr.arpa.: domain name does not exist
[0] 246.3.207.216.in-addr.arpa.: domain name does not exist
[0] 247.3.207.216.in-addr.arpa.: domain name does not exist
[0] 248.3.207.216.in-addr.arpa.: domain name does not exist
[0] 249.3.207.216.in-addr.arpa.: domain name does not exist
[0] 250.3.207.216.in-addr.arpa.: domain name does not exist
[0] 251.3.207.216.in-addr.arpa.: domain name does not exist
[0] 252.3.207.216.in-addr.arpa.: domain name does not exist
[0] 253.3.207.216.in-addr.arpa.: domain name does not exist
[0] 254.3.207.216.in-addr.arpa.: domain name does not exist
[0] 255.3.207.216.in-addr.arpa.: domain name does not exist