Warrant activity for the years ending December 31, 2013 and 2012 are as follows:
| Numbers of Warrants | Weighted-Average Exercise Price | |||||||
| Outstanding at January 1, 2012 | 896,092 | $ | 32.00 | |||||
| Issued | 250,000 | 24.00 | ||||||
| Cancelled or expired | (14,699 | ) | (100.00 | ) | ||||
| Exercised | — | |||||||
| Outstanding at December 31, 2012 | 1,131,393 | $ | 32.00 | |||||
| Issued | 123,771 | 28.00 | ||||||
| Cancelled or expired | (44,981 | ) | (28.00 | ) | ||||
| Exercised | — | — | ||||||
| Outstanding at December 31, 2013 | 1,210,238 | $ | 28.00 | |||||
| Weighted average grant date fair value of warrants granted during the year ended December 31, 2013 | $ | 3.96 | ||||||
Series A warrant activity for the years ending December 31, 2013 and 2012 are as follows:
| Numbers of Series A Warrants | Weighted-Average Exercise Price | |||||||
| Outstanding at January 1, 2012 | 446 | $ | 2,440.00 | |||||
| Issued | — | — | ||||||
| Cancelled or expired | — | — | ||||||
| Exercised | — | — | ||||||
| Outstanding at December 31, 2012 | 446 | $ | 2,800.00 | |||||
| Issued | — | — | ||||||
| Cancelled or expired | — | — | ||||||
| Exercised | — | — | ||||||
| Outstanding at December 31, 2013 | 446 | $ | 2,800.00 | |||||
| Weighted average fair value granted during the year ended December 31, 2013 | $ | — | ||||||