STOCK-BASED COMPENSATION - Stock-based compensation expenses (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
STOCK-BASED COMPENSATION
Stock compensation in continuing operations	$ 63,000	$ 169,000	$ 142,000	$ 540,000
Stock compensation in discontinued operations		437,000		725,000
Total stock compensation expenses	63,000	606,000	142,000	1,265,000
Research and development
STOCK-BASED COMPENSATION
Stock compensation in continuing operations	4,000	42,000	10,000	193,000
General and administrative
STOCK-BASED COMPENSATION
Stock compensation in continuing operations	$ 59,000	$ 127,000	$ 132,000	$ 347,000