Consolidated Statements of Cash Flows - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Cash flows from operating activities:
Net loss	$ (9,500,000)	$ (9,680,000)
Adjustments to reconcile net loss to net cash used in operating activities:
Common stock issued for services	242,000	342,000
Share based compensation	224,000	369,000
Depreciation and amortization	271,000	297,000
Abandonment and impairment of capitalized patent costs	322,000	0
Change in operating assets and liabilities:
Contract assets	145,000	(184,000)
Accounts receivable	0	103,000
Prepaid expenses and other assets	(134,000)	169,000
Accounts payable and accrued liabilities	312,000	13,000
Accrued compensation and taxes	(266,000)	428,000
Contract liabilities	0	(115,000)
Net cash used in operating activities	(8,384,000)	(8,258,000)
Cash flows from investing activities:
Acquisition of fixed assets	(94,000)	(94,000)
Disbursements for patents and other intangible assets	(408,000)	(327,000)
Investment in short-term treasury bills	(6,923,000)	0
Net cash used in investing activities	(7,425,000)	(421,000)
Cash flows from financing activities:
Proceeds from issuance of common stock and units of common stock and warrants for cash, net of offering costs	23,511,000	8,667,000
Net cash provided by financing activities	23,511,000	8,667,000
Net increase (decrease) in cash and cash equivalents	7,702,000	(12,000)
Cash and cash equivalents, beginning of year	1,247,000	1,259,000
Cash and cash equivalents, end of year	$ 8,949,000	$ 1,247,000