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STOCK-BASED COMPENSATION (Details 1)	3 Months Ended
STOCK-BASED COMPENSATION (Details 1)	Mar. 31, 2013	Mar. 31, 2012
Weighted average risk-free interest rate	0.81%	0.78%
Expected life of options	5 years	5 years
Expected dividend yield	0.00%	0.00%
Weighted average expected volatility	103.78%	85.97%

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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