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Equity (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2022
Schedule of Outstanding, Reserved and Authorized Shares under Share-based Compensation Plans | ​
​ | ​ | ​ | ​ | ​
​ | ​ | December 31, | ​ | December 31,
(in thousands) |  | 2022 |  | 2021
Outstanding options and restricted stock units |  | 3,202 |  | 3,076
Reserved but unissued shares under the Plans | ​ | 2,777 | ​ | 2,901
Total authorized shares under the Plans |  | 5,979 |  | 5,977
​
Schedule of weighted-average assumptions used in calculation of fair value of stock options | During the year ended December 31, 2022, the following weighted-average assumptions were utilized in the calculation of the fair value of stock options: ​
​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | December 31, | ​
​ | ​ | 2022 | ​ | ​ | 2021 | ​
Expected life |  | 5.71 years |  | ​ | 6.01 years | ​
Weighted average volatility | ​ | 77.64 | % | ​ | 91.89 | %
Weighted average risk-free interest rate | ​ | 1.39 | % | ​ | 0.59 | %
Expected dividend rate | ​ | 0 | % | ​ | 0 | %
​
Schedule of stock option activity | A summary of the Company’s stock option activity and changes is as follows: ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | December 31,
​ | ​ | 2022
(in thousands) | ​ | Options to Purchase Common Stock | ​ | Weighted Average Exercise Price | ​ | Weighted Average Remaining Contractual Life (in years)
Outstanding at beginning of year |  | 2,964 | ​ | $ | 2.06 |  | 6.89
Granted |  | 88 | ​ | $ | 1.26 |  | 9.01
Exercised |  | (43) | ​ | $ | 0.89 |  | —
Forfeited/Expired |  | (230) | ​ | $ | 1.99 |  | —
Outstanding at end of year |  | 2,779 | ​ | $ | 2.05 |  | 6.43
Exercisable at end of year |  | 1,986 | ​ | $ | 1.70 |  | 5.89
​
Restricted Stock Units |
Schedule of Compensation Expense | ​
​ | ​ | ​ | ​ | ​ | ​
​ | For the Year Ended
​ | December 31,
​ | 2022 |  | 2021
Compensation Expense | $ | 252 | $ | - | ​
Weighted Average Value Per Share | $ | 1.57 | $ | - | ​
​
Schedule of restricted stock unit activity | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | December 31, | ​ | December 31,
​ | ​ | 2022 | ​ | 2021
(in thousands) | ​ | Number of Shares | ​ | Weighted Average Grant Date Fair Value | ​ | Number of Shares | ​ | Weighted Average Grant Date Fair Value
Nonvested at beginning of year |  | 112 | ​ | $ | 2.28 | ​ | — | ​ | $ | —
Granted |  | 376 | ​ | $ | 1.30 | ​ | 112 | ​ | $ | 2.28
Vested |  | (65) | ​ | $ | 1.77 | ​ | - | ​ | $ | —
Nonvested at end of year |  | 423 | ​ | $ | 1.49 | ​ | 112 | ​ | $ | 2.28
​
Warrant [Member] |
Schedule Of warrant activity | A summary of warrant activity and related information is as follows: ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | December 31,
​ | ​ | 2022 | ​ | 2021
​ |  | ​ |  | Weighted |  | ​ |  | Weighted
​ | ​ | ​ | ​ | Average | ​ | ​ | ​ | Average
​ | ​ | ​ | ​ | Exercise | ​ | ​ | ​ | Exercise
(in thousands) | ​ | Warrants | ​ | Price | ​ | Warrants | ​ | Price
Outstanding at beginning of year | ​ | — | ​ | $ | — |  | 80 | ​ | $ | 1.80
Granted | ​ | — | ​ |  | — |  | — | ​ | ​ | —
Exercised | ​ | — | ​ |  | — |  | (38) | ​ |  | 1.80
Forfeited/Expired | ​ | — | ​ | ​ | — |  | (43) | ​ | ​ | 1.80
Outstanding at end of year | ​ | — | ​ | $ | — |  | — | ​ | $ | —
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Equity Incentive Plan [Member] |
Schedule of Compensation Expense | ​
​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | For the Year Ended
​ | ​ | December 31,
​ |  | 2022 |  | 2021
Fair value | ​ | $ | 98 | ​ | $ | 217
Weighted Average Value Per Share | ​ | $ | 1.43 | ​ | $ | 3.37
​
Consultant Stock Plan |
Schedule of share-based compensation activity | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | December 31,
(in thousands) |  |  | 2022 |  | 2021
Reserved but unissued shares at beginning of year | ​ | ​ | ​ | 211 | ​ | ​ | 212
Increases in the number of authorized shares | ​ | ​ |  | — | ​ |  | 14
Grants | ​ | ​ |  | (15) | ​ |  | (15)
Reserved but unissued shares at end of year | ​ | ​ |  | 196 | ​ |  | 211
​
Schedule of Compensation Expense | ​
​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | For the Year Ended
​ | ​ | December 31,
​ |  | 2022 |  | 2021
Compensation Expense | ​ | $ | 26 | ​ | $ | 33
Weighted Average Value Per Share | ​ | $ | 1.61 | ​ | $ | 2.23
​

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