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Note 6 - Derivative Liability (Details) - USD ($) $ / shares in Units, $ in Thousands | 7 Months Ended | 12 Months Ended
--- | --- | ---
Jul. 31, 2020 | Dec. 31, 2020
Derivative Liability [Abstract] |  |
Stock price | $ 3.06 | $ 7.21
Risk-free interest rate | 0.26% | 0.36%
Expected volatility | 134.00% | 135.00%
Expected life (in years) | 5 years | 4 years 7 months 6 days
Expected dividend yield | $ 0 | $ 0
Fair value of warrants | $ 153 | $ 383

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- Definition Percentage rate that is indicative of an expected degree of movement against a base line index, and which is included in determining the amount of the specified guaranteed benefit obligation as of the balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 80 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=121641442&loc=d3e19393-158473 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 20 -Section 55 -Paragraph 15 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=121639652&loc=d3e7104-158389 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=121643868&loc=d3e14931-158439 + Details
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