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Note 4 - Stock-Based Compensation (Detail) - Weighted Average Assumptions for Stock Options Fair Value Estimate	3 Months Ended
	Oct. 31, 2012
Weighted average risk-free interest rate	0.70%
Expected life (in years)	5 years 6 months
Expected stock volatility	121.00%
Expected forfeitures	8.20%

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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