8.Long-Term Investments

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Long term investments consist of the following for the periods presented:

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In September 2020, the Company acquired a promissory note from NeuroDiagnostics Inc., which is doing business as SYNAPS Dx, in the principal amount of $500, $100 of which was retained for expense reimbursement. Subsequently, in December

2020, the Company agreed to convert the promissory note, together with all accrued interest thereon, into shares of preferred stock of SYNAPS Dx as repayment in full of the promissory note. The value of the note exchanged for the shares of preferred stock of SYNAPS Dx held by the Company as of June 30, 2025 and December 31, 2024 was approximately $512.

The investments in SYNAPS Dx were recorded in accordance with ASC 321, Investments – Equity Securities (“ASC 321”), which provides that investments in equity securities in privately-held companies without readily determinable fair values are generally recorded at cost, plus or minus subsequent observable price changes in orderly transactions for identical or similar investments, less impairments. The Company elected the practical expedient permitted by ASC 321 and recorded the above investments on a cost basis. As a part of the assessment for impairment indicators, the Company considers significant deterioration in the earnings performance and overall business prospects of the investee as well as significant adverse changes in the external environment these investments operate. If qualitative assessment indicates the investments are impaired, the fair value of these equity securities would be estimated, which would involve a significant degree of judgement and subjectivity.

The Company qualitatively assessed the investment for impairment in accordance with ASC 321. As of June 30, 2025 and December 31, 2024, the Company determined that there was no impairment for the investment in SYNAPS Dx.