Note 5 - Loss Per Share (Tables)

6 Months Ended

12 Months Ended

Jun. 30, 2018

Dec. 31, 2017

Notes Tables

Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]

	Three Months Ended June 30,						Six Months Ended June 30,
	2018			2017			2018			2017
Numerator
Net loss available in basic and diluted calculation	$	(2,373,410	)	$	(2,543,670	)	$	(4,133,432	)	$	(3,885,517	)
Comprehensive loss		(2,373,410	)		(2,543,670	)		(4,133,432	)		(3,885,517	)
Denominator:
Weighted average common shares outstanding-basic		11,878,490			6,167,689			11,632,221			6,308,554
Effect of diluted stock options, warrants and preferred stock (1)		-			-			-			-
Weighted average common shares outstanding-basic		11,878,490			6,167,689			11,632,221			6,308,554
Loss per common share-basic and diluted	$	(0.20	)	$	(0.41	)	$	(0.36	)	$	(0.62	)

	Year Ended December 31,
	2017			2016
Numerator:
Net loss available in basic and diluted calculation	$	(7,746,593	)	$	(6,526,014	)
Other comprehensive income:
Unrealized gain (loss) from marketable securities		-			1,501
Comprehensive (loss)		(7,746,593	)		(6,524,513	)
Denominator:
Weighted average common shares outstanding-basic		6,362,989			2,823,345
Effect of dilutive stock options, warrants and preferred stock (1)		-			-
Weighted average common shares outstanding-basic		6,362,989			2,823,345
Loss per common share-basic and diluted	$	(1.22	)	$	(2.31	)