

	June 30,		December 31,
	2020		2019
Leasehold improvements	$	2,482	$	2,248
Laboratory equipment		792		677
Furniture, fixtures, and equipment		789		466
Software		117		118
Construction in progress		110		543
		4,290		4,052
Less: Accumulated depreciation		(1,699)		(1,486)
	$	2,591	$	2,566

Depreciation expense was $0.1 million for the three-month periods ended June 30, 2020 and 2019, respectively. Depreciation expense was $0.2 million and $0.3 million for the six-month periods ended June 30, 2020 and 2019, respectively.

Intangible assets primarily consist of acquired licenses to utilize certain patents, know-how and technology relating to the Company’s NPS technology for biomedical applications acquired from Old Dominion University Research Foundation (ODURF), Eastern Virginia Medical School, and the University of Southern California. In addition, the Company entered into a Sponsored Research Agreement with Old Dominion University’s Frank Reidy Research Center for Bioelectrics, which includes certain intellectual property rights arising from the research. The Company is amortizing the intangible assets over an estimated useful life of 12 years.



	June 30,		December 31,
	2020		2019
Acquired patents and licenses	$	7,985	$	7,985
Less: Accumulated amortization		(3,771)		(3,438)
	$	4,214	$	4,547

A schedule of the amortization of intangible assets for the remainder of 2020 and the succeeding five fiscal years and thereafter is as follows (in thousands):


Year Ending December 31:
2020 (remaining 6 months)	$	332
2021		665
2022		665
2023		665
2024		665
2025		665
Thereafter		557
	$	4,214



	June 30,		December 31,
	2020		2019
Compensation expense	$	1,917	$	1,699
Accrued clinical		282		262
Professional fees		62		51
Property and equipment		234		234
Other		628		250
	$	3,123	$	2,496