CONDENSED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
CASH FLOWS FROM OPERATING ACTIVITIES
Net loss	$ (7,038)	$ (4,470)
Adjustments to reconcile net loss to net cash used in operating activities:
Gain on investments held to maturity	(11)
Amortization of discounts on investments held to maturity	1
Bad debts	2
Depreciation and amortization	154	94
Stock-based compensation	1,872	1,473
Non-cash charge for settlement of dispute		300
Amortization of debt discount		27
(Gain) loss on remeasurement of common stock warrant liability	(36)	(51)
Loss on extinguishment of unsecured promissory note		112
(Increase) decrease in current assets:
Accounts receivable	(1)	(1)
Prepaid expenses	145	1
Inventory	(243)
Deposits	(217)
Increase (decrease) in current liabilities:
Accounts payable	68	(151)
Accrued contract cancellation settlement	(1,000)
Accrued expenses	655	19
Deferred rent	13
Deferred revenues		(93)
Net cash used in operating activities	(5,636)	(2,740)
CASH FLOWS FROM INVESTING ACTIVITIES
Purchase of securities held to maturity	(2,940)
Purchase of property and equipment	(863)	(45)
Net cash used in investing activities	(3,803)	(45)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from the issuance of series B convertible preferred stock		896
Proceeds from the issuance of common stock		6,199
Proceeds from the issuance of convertible notes payable		436
Repayments of convertible notes payable		(810)
Proceeds from the issuance of notes payable	389
Repayments of notes payable	(23)	(5)
Repayments of notes payable, related parties	(16)	(628)
Repayments of capital lease obligations	(63)	(10)
Payment of deferred offering costs		(444)
Proceeds from exercise of stock options and warrants		326
Net cash provided by financing activities	287	5,960
NET CHANGE IN CASH	(9,152)	3,175
CASH AT BEGINNING OF PERIOD	11,826	141
CASH AT END OF PERIOD	2,674	3,316
SUPPLEMENTAL INFORMATION:
Interest paid	22	16
Income taxes paid
NON-CASH INVESTING AND FINANCING ACTIVITIES:
Purchases of equipment under capital lease obligations	316
Original issue discount		147
Debt discount on convertible notes		9
Contributed capital, debt forgiveness by related parties		2,003
Issuance of series B convertible preferred stock in connection with conversion of convertible notes and notes payable		16
Issuance of shares of common stock upon conversion of Series B convertible preferred stock		260
Dividends		$ 60