Quarterly report pursuant to Section 13 or 15(d)

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Note 9 - October 2019 Registered Direct Offering (Details Textual)

v3.22.4

Note 9 - October 2019 Registered Direct Offering (Details Textual)	Dec. 31, 2022 shares	Feb. 17, 2021 shares	Oct. 18, 2019 USD ($) $ / shares shares	Oct. 10, 2019 USD ($)	Sep. 30, 2022 shares
Stock Issued During Period, Shares, New Issues	4,000,000	215,625
Series I Warrant [Member]
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right			1
Class of Warrant or Right, Exercise Price of Warrants or Rights \| $ / shares			$ 44.00
October 2019 Placement Agent Warrants [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights \| $ / shares			$ 43.75
Class of Warrant or Right, Number of Securities Called by Warrants or Rights			5,358
Warrants and Rights Outstanding, Term			5 years
Class of Series I Warrant [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights					71,429
Proceeds from Subscribed, Unissued Common Stock and Warrants \| $				$ 2,500,000
Payments of Stock Issuance Costs \| $				$ 158,000
Class of Series I Warrant [Member] \| Minimum [Member]
Percentage of Fee on Gross Proceeds of Warrants			0.060
Class of Series I Warrant [Member] \| Maximum [Member]
Percentage of Fee on Gross Proceeds of Warrants			0.082
Placement Agent Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights					5,358
October 2019 Registered Direct Offering [Member]
Stock Issued During Period, Shares, New Issues			71,429
Shares Issued, Price Per Share \| $ / shares			$ 35.00
Registered Direct Offering October 2019 [Member]
Stock Issued During Period, Shares, New Issues			71,429
Proceeds from Subscribed, Unissued Common Stock and Warrants \| $			$ 2,500,000
Payments of Financing Costs, Total \| $			333,000
Payments of Stock Issuance Costs \| $			$ 158,000

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