Note 15 - The Financing and Warrant Liabilities (Tables)

12 Months Ended

Dec. 31, 2023

Notes Tables

Schedule of Warrant Liabilities [Table Text Block]

	As of December 31, 2023		As of December 31, 2022		Change in Fair Value (Gain)/Loss
	(US$’000)		(US$’000)		(US$’000)
Warrants issued in the 2021 Financing:
--Investor warrants		-		86		(86	)
--Placement agent warrants		-		9		(9	)
Warrants issued in the 2020 Financing:
--Investor warrants		-		76		(76	)
--Placement agent warrants		-		14		(14	)
Warrant liabilities		-		185		(185	)

	As of December 31, 2022		As of December 31, 2021		Change in Fair Value (Gain)/Loss
	(US$’000)		(US$’000)		(US$’000)
Warrants issued in the 2021 Financing:
--Investor warrants		86		964		(878	)
--Placement agent warrants		9		132		(123	)
Warrants issued in the 2020 Financing:
--Investor warrants		76		795		(719	)
--Placement agent warrants		14		148		(134	)
Warrant liabilities		185		2,039		(1,854	)

Schedule of Warrant Activity [Table Text Block]

	Warrant Outstanding							Warrant Exercisable
	Number of underlying shares			Weighted Average Remaining Contractual Life (Years)		Weighted Average Exercise Price		Number of underlying shares			Weighted Average Remaining Contractual Life (Years)		Weighted Average Exercise Price
Balance, January 1, 2022		1,000,343			2.36	$	15.11		1,000,343			2.36	$	15.11
Issued/Vested		-							-
Exercised		-							-
Balance, December 31, 2022		1,000,343			1.36	$	15.11		1,000,343			1.36	$	15.11
Issued/Vested		-							-
Exercised		-
Expired		(406,175	)			$	10.15		(406,175	)			$	10.15
Balance, December 31, 2023		594,168			0.63	$	18.50		594,168			0.63	$	18.50

Warrant [Member]

Notes Tables

Fair Value Measurement Inputs and Valuation Techniques [Table Text Block]

	2021 Investors Warrants									2021 Placement Agent Warrants
	December 31, 2023			December 31, 2022			December 31, 2021			December 31, 2023			December 31, 2022			December 31, 2021
Stock price #	$	0.83		$	0.46		$	1.00		$	0.83		$	0.46		$	1.00
Years to maturity		0.6			1.63			2.63			0.6			1.63			2.63
Risk-free interest rate		5.13	%		4.625	%		0.87	%		5.13	%		4.625	%		0.87	%
Dividend yield		-			-			-			-			-			-
Expected volatility		82	%		99.74	%		115	%		82	%		99.74	%		115	%
Exercise Price #	$	17.95		$	3.59		$	3.59		$	22.4375		$	4.4875		$	4.4875
Fair value of the warrant	$	-		$	0.0329		$	0.37		$	-		$	0.0256		$	0.36
Warrant Liabilities (US$’000)	$	-		$	86		$	964		$	-		$	9		$	132

	2020 Investors Warrants							2020 Placement Agent Warrants
	December 31, 2023*	December 31, 2022			December 31, 2021			December 31, 2023*	December 31, 2022			December 31, 2021
Stock price #		$	0.46		$	1.00			$	0.46		$	1.00
Years to maturity			0.95			1.95				0.95			1.95
Risk-free interest rate			4.716	%		0.72	%			4.716	%		0.72	%
Dividend yield			-			-				-			-
Expected volatility			115.61	%		128	%			115.61	%		128	%
Exercise Price #		$	2.03		$	2.03			$	2.03		$	2.03
Fair value of the warrant		$	0.0439		$	0.46			$	0.0456		$	0.49
Warrant Liabilities (US$’000)		$	76		$	795			$	14		$	148