Derivative Liabilities (Tables)

3 Months Ended

Oct. 31, 2013

Notes to Financial Statements

Derivative warrant liability

	Value			No. of Warrants
Balance at August 1, 2012 – Derivative warrant liability	$	4,081,627			55,148,530
Additional warrants issued in August 2012 financing		624,797			9,375,000
Additional warrants issued in December 2012 financing		762,355			24,999,999
Additional warrants issued in June 2013 financing		1,189,744			40,833,335
Additional warrants from price protection features of existing warrants		7,484,550			236,219,094
Exercise of warrants		(5,629,130	)		(145,888,421	)
Decrease in fair value of derivative warrant liability		(3,279,650	)		n/a
Balance at July 31, 2013 – Derivative warrant liability	$	5,234,293			220,687,537
Exercise of warrants		(47,842	)		(2,166,666	)
Decrease in fair value of derivative warrant liability		(1,048,859	)		n/a
Balance at October 31, 2013 – Derivative warrant liability	$	4,137,592			218,520,871

Fair value assumptions, derivative warrant liability

	October 31, 2013			July 31, 2013
Current exercise price	$	0.03		$	0.03
Time to expiration		3.2 years			3.5 years
Risk-free interest rate		0.57	%		0.49	%
Estimated volatility		81	%		85	%
Dividend		-0-			-0-
Stock price at period end date	$	0.03		$	0.035

Fair value assumptions, derivative additional investment rights liability

	October 31, 2013			July 31, 2013
Underlying number of units of convertible preferred stock		1,225			1,225
Underlying number of units of warrants		40,833,335			40,833,335
Current exercise price of warrants	$	0.03		$	0.03
Current conversion price of preferred stock	$	0.03		$	0.03
Time to expiration		0.63 years			0.88 years
Risk-free interest rate		0.09	%		0.11	%
Estimated volatility		51	%		114	%
Dividend		-0-			-0-
Stock price at period end date	$	0.03		$	0.035