Note 5 - Share Based Compensation - Expenses for Continuing Operations (Details) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Share-based compensation expense	$ 196,346	$ 228,710	$ 895,821	$ 802,993
Selling, General and Administrative Expenses [Member]
Share-based compensation expense	170,758	207,047	770,524	714,167
Research and Development Expense [Member]
Share-based compensation expense	$ 25,588	$ 21,663	$ 125,297	$ 88,826

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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