Activity measurements of the radionuclides <sup>18</sup>F, <sup>64</sup>Cu, <sup>99m</sup>Tc and <sup>11</sup>C for the NRC, Canada, in the ongoing comparisons BIPM.RI(II)-K4 series and KCRV update in the corresponding BIPM.RI(II)-K1 comparison
Bibliographic record
Abstract
Main text In 2017, comparisons of activity measurements of 18F, 64Cu, 99mTc and 11C using the Transfer Instrument of the International Reference System (SIRTI) took place at the National Research Council of Canada (NRC, Canada). Ampoules containing 18F, 64Cu, 99mTc and 11C solutions were measured in the SIRTI for about three half-lives (10 half-lives for 11C). The NRC standardized the activity in the ampoules by 4π(PC)β−γ anti-coincidence measurements (CIEMAT/NIST liquid scintillation counting for 11C). The comparisons, identifiers BIPM.RI(II)-K4.F-18, BIPM.RI(II)-K4.Cu-64 and BIPM.RI(II)-K4.Tc-99m are linked to the corresponding BIPM.RI(II)-K1.F-18, BIPM.RI(II)-K1.Cu-64 and BIPM.RI(II)-K1.Tc-99m comparisons. The BIPM.RI(II)-K1 18F and 99mTc key comparison reference values have been updated to include the latest BIPM.RI(II)-K4 linked results and degrees of equivalence for those three comparisons have been evaluated. To reach the main text of this paper, click on Final Report . Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/ . The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.002 | 0.003 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.001 |
| Bibliometrics | 0.002 | 0.002 |
| Science and technology studies | 0.002 | 0.001 |
| Scholarly communication | 0.002 | 0.001 |
| Open science | 0.002 | 0.001 |
| Research integrity | 0.001 | 0.002 |
| Insufficient payload (model declined to judge) | 0.018 | 0.010 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".