Note 16 - Warrant Liabilities (Tables)

9 Months Ended

Sep. 30, 2022

Notes Tables

Schedule of Warrant Liabilities [Table Text Block]

	As of September 30, 2022		As of June 30, 2022		As of December 31, 2021		Change in Fair Value (gain)/loss
							Nine Months Ended September 30, 2022			Three Months Ended September 30, 2022
	(US$’000)		(US$’000)		(US$’000)		(US$’000)			(US$’000)
Warrants issued in the 2021 Financing:
--Investor Warrants		782		167		964		(182	)		615
--Placement Agent Warrants		106		22		132		(26	)		84
Warrants issued in the 2020 Financing:
--Investor Warrants		328		57		795		(467	)		271
--Placement Agent Warrants		64		11		148		(84	)		53
Warrant Liabilities		1,280		257		2,039		(759	)		1,023

											Change in Fair Value (gain)/loss
	As of September 30, 2021		As of  July 2, 2021		As of  June 30, 2021		As of  February 18, 2021		As of  December 31, 2020		Nine Months Ended September 30, 2021			Three Months Ended September 30, 2021
	(US$’000)		(US$’000)		(US$’000)		(US$’000)		(US$’000)		(US$’000)			(US$’000)
Warrants issued in the 2021 Financing:
--Investor Warrants		1,824		*		3,257		10,476		*		(8,652	)		(1,433	)
--Placement Agent Warrants		237		*		431		1,445		*		(1,208	)		(194	)
Warrants issued in the 2020 Financing:
--Investor Warrants		1,383		*		2,420		*		1,279		104			(1,037	)
--Placement Agent Warrants		242		*		423		*		224		18			(181	)
Warrants issued in the 2018 Financing:
--Placement Agent Warrants		-		58		66		*		2		56			(8	)
		3,686		58		6,597		11,921		1,505		(9,682	)		(2,853	)

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		5,001,705		2.36	$	3.02		5,001,705		2.36	$	3.02
Granted/Vested		-						-
Exercised		-						-
Balance, September 30, 2022 (Unaudited)		5,001,705		1.61	$	3.02		5,001,705		1.61	$	3.02

Warrant [Member]

Notes Tables

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

	2021 Investors Warrants									2021 Placement Agent Warrants
	September 30, 2022			June 30, 2022			December 31, 2021			September 30, 2022			June 30, 2022			December 31, 2021
Stock price	$	0.92		$	0.34		$	1.00		$	0.92		$	0.34		$	1.00
Years to maturity		1.88			2.13			2.63			1.88			2.13			2.63
Risk-free interest rate		4.16	%		2.97	%		0.87	%		4.16	%		2.97	%		0.87	%
Dividend yield		-			-			-			-			-			-
Expected volatility		127	%		124	%		115	%		127	%		124	%		115	%
Exercise Price	$	3.59		$	3.59		$	3.59		$	4.4875		$	4.4875		$	4.4875
Fair value of the warrant	$	0.297		$	0.064		$	0.37		$	0.287		$	0.061		$	0.36
Warrant Liabilities (US$’000)	$	782		$	167		$	964		$	106		$	22		$	132

	2021 Investors Warrants									2021 Placement Agent Warrants
	September 30, 2021			June 30, 2021			February 18, 2021*			September 30, 2021			June 30, 2021			February 18, 2021*
Stock price	$	1.26		$	2.00		$	4.48		$	1.26		$	2.00		$	4.48
Years to maturity		2.88			3.14			3.50			2.88			3.14			3.50
Risk-free interest rate		0.50	%		0.48	%		0.26	%		0.50	%		0.48	%		0.26	%
Dividend yield		-			-			-			-			-			-
Expected volatility		115	%		114	%		168	%		115	%		114	%		168	%
Exercise Price	$	3.59		$	3.59		$	3.59		$	4.4875		$	4.4875		$	4.4875
Fair value of the warrant	$	0.70		$	1.25		$	4.02		$	0.65		$	1.18		$	3.96
Warrant Liabilities (US$’000)	$	1,824		$	3,257		$	10,476		$	237		$	431		$	1,445

	2020 Investors Warrants									2020 Placement Agent Warrants
	September 30, 2022			June 30, 2022			December 31, 2021			September 30, 2022			June 30, 2022			December 31, 2021
Stock price	$	0.92		$	0.34		$	1.00		$	0.92		$	0.34		$	1.00
Years to maturity		1.20			1.45			1.95			1.20			1.45			1.95
Risk-free interest rate		3.90	%		2.79	%		0.72	%		3.90	%		2.79	%		0.72	%
Dividend yield		-			-			-			-			-			-
Expected volatility		103	%		107	%		128	%		103	%		107	%		128	%
Exercise Price	$	2.03		$	2.03		$	2.03		$	2.03		$	2.03		$	2.03
Fair value of the warrant	$	0.195		$	0.033		$	0.46		$	0.211		$	0.036		$	0.49
Warrant Liabilities (US$’000)	$	328		$	57		$	795		$	64		$	11		$	148

	2020 Investors Warrants									2020 Placement Agent Warrants
	September 30, 2021			June 30, 2021			December 31, 2020			September 30, 2021			June 30, 2021			December 31, 2020
Stock price	$	1.26		$	2.00		$	1.35		$	1.26		$	2.00		$	1.35
Years to maturity		2.20			2.45			2.95			2.20			2.45			2.95
Risk-free interest rate		0.34	%		0.34	%		0.17	%		0.34	%		0.34	%		0.17	%
Dividend yield		-			-			-			-			-			-
Expected volatility		122	%		120	%		102	%		122	%		120	%		102	%
Exercise Price	$	2.03		$	2.03		$	2.03		$	2.03		$	2.03		$	2.03
Fair value of the warrant	$	0.80		$	1.40		$	0.74		$	0.80		$	1.40		$	0.74
Warrant Liabilities (US$’000)	$	1,383		$	2,420		$	1,279		$	242		$	423		$	224

	2018 Placement Agent Warrants
	July 2, 2021*			June 30, 2021			December 31, 2020
Stock price	$	1.94		$	2.00		$	1.35
Years to maturity		0.04			0.05			0.05
Risk-free interest rate		0.05	%		0.04	%		0.08	%
Dividend yield		-			-			-
Expected volatility		75	%		74	%		59	%
Exercise Price	$	1.4927		$	1.4927		$	1.4927
Fair value of the warrant	$	0.45		$	0.51		$	0.02
Warrant liabilities (US$’000)	$	58		$	66		$	2