Consolidated Statements of Cash Flows (Unaudited) - USD ($)	6 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
CASH FLOWS FROM OPERATING ACTIVITIES:
Net loss	$ (1,713,000)	$ (2,922,000)
Adjustments to reconcile net loss to net cash used by operating activities:
Depreciation expense	77,000	65,000
Gain on equipment disposals		(23,000)
Amortization of other assets	20,000	25,000
Accretion of asset retirement obligation	15,000	16,000
Gain on change in ARO estimate due to lease modification	(73,000)
Share-based compensation	185,000	190,000
Changes in operating assets and liabilities:
Accounts receivable, net	(255,000)	85,000
Inventory	13,000	53,000
Prepaid expenses and other current assets	(190,000)	(20,000)
Accounts payable and accrued expenses	(51,000)	(195,000)
Accrued protocol expense	(109,000)	36,000
Accrued radioactive waste disposal	15,000	18,000
Accrued payroll and related taxes	114,000	(35,000)
Accrued vacation	21,000	(19,000)
Net cash used by operating activities	(1,931,000)	(2,726,000)
CASH FLOWS FROM INVESTING ACTIVITIES:
Additions to property and equipment	(204,000)	(225,000)
Proceeds from sale of equipment		23,000
Proceeds from maturity of certificates of deposit		4,418,000
Purchases of and interest from U.S. Treasury Securities		(8,259,000)
Net cash used by investing activities	(204,000)	(4,043,000)
CASH FLOWS FROM FINANCING ACTIVITIES:
Preferred dividends paid	(11,000)	(11,000)
Proceeds from sales of common stock, pursuant to registered direct offering, net		7,381,000
Net cash (used) provided by financing activities	(11,000)	7,370,000
Net increase (decrease) in cash, cash equivalents, and restricted cash	(2,146,000)	601,000
Cash, cash equivalents, and restricted cash beginning of period	5,507,000	2,781,000
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH END OF PERIOD	3,361,000	3,382,000
Reconciliation of cash, cash equivalents, and restricted cash to the consolidated balance sheets:
Cash and cash equivalents	3,180,000	3,201,000
Restricted cash	181,000	181,000
Total cash, cash equivalents, and restricted cash shown on the consolidated statements of cash flows	3,361,000	3,382,000
Non-cash investing and financing activities:
Recognition of operating lease liability and right of use asset	1,228,000
Warrants issued to placement agent of registered direct offering		$ 163,000