Note 10 - Stockholders' Equity, Stock Options and Warrants (Tables)

3 Months Ended

Mar. 31, 2024

Notes Tables

Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

	Three Months Ended March 31,
	2024	2023
	Stock Options
Expected dividend yield	-	0.0%
Expected stock price volatility	-	90.8%
Risk-free interest rate	-	3.38% – 3.55%
Expected life (years)	-	10

Share-Based Payment Arrangement, Activity [Table Text Block]

	Stock Options					Warrants
	Number of Shares			Average Exercise Price		Number of Shares			Average Exercise Price
Outstanding as of December 31, 2023		47,664		$	82.23		1,806,589		$	21.52
Issued		-			-		-			-
Forfeited		(74	)		3.44		-			-
Expired		(89	)		302.80		(7,159	)		200.00
Outstanding as of March 31, 2024		47,501		$	81.94		1,799,430		$	20.81