Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Assets
Cash and cash equivalents	$ 1,590	$ 11,260
Restricted cash	120
Short-term investments		14,751
Accounts receivable, net	671	719
Inventories, net	325	658
Other inventory supplies	124	133
Prepaid expenses and other current assets	47	167
Assets held for sale		529
Total current assets	2,877	28,217
Grants receivable	250
Inventories, non-current, net	650	468
Property and equipment, net	2,182	2,301
Total assets	5,959	30,986
Liabilities and stockholders’ equity
Accounts payable	438	545
Accrued payroll	128	426
Accrued and other current liabilities	223	220
Corporate income and franchise taxes	304	327
Accrued real estate taxes	67	78
Advance payments	4	2
Current portion of long term debt, net of unamortized finance costs	25
Total current liabilities	1,189	1,598
Long term debt, net of current portion and unamortized finance costs	1,566
Total liabilities	2,755	1,598
Commitments and contingencies (see Note 11)
Stockholders’ equity
Preferred stock, $0.001 par value, 1,000,000 undesignated shares authorized, no shares issued or outstanding
Common stock, $0.001 par value 8,200,000 shares authorized; 3,011,917 and 2,995,680 shares issued; 2,462,889 and 2,446,652 shares outstanding	29	29
Additional paid-in capital	349,520	376,640
Treasury stock, at cost, 549,028 and 549,028 shares	(15,147)	(15,147)
Accumulated other comprehensive loss		(1)
Accumulated deficit	(331,198)	(332,133)
Total stockholders’ equity	3,204	29,388
Total liabilities and stockholders’ equity	$ 5,959	$ 30,986