Note 3 - Summary of Significant Accounting Policies (Details Textual)	3 Months Ended	12 Months Ended
Mar. 31, 2024	Dec. 31, 2023 $ / shares	Jun. 30, 2023 $ / shares
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Dividend Rate	0.00%	0.00%
Prefunded Warrant [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights		$ 0.001	$ 0.001
Convertible Debt [Member] \| Measurement Input, Expected Term [Member]
Debt Instrument, Measurement Input	0.69	0.94
Convertible Debt [Member] \| Measurement Input, Price Volatility [Member]
Debt Instrument, Measurement Input	0.75	0.80
Convertible Debt [Member] \| Measurement Input, Cost to Sell [Member]
Debt Instrument, Measurement Input	0.553	0.552

Exercise price per share or per unit of warrants or rights outstanding.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-3

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Value of input used to measure debt instrument, including, but not limited to, convertible and non-convertible debt.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(iii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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