CRAPT: an improved version of APT with compensation for variations in JCH
Bibliographic record
Abstract
A modified version of the attached proton test (APT) sequence for (13)C spectral editing, which we call CRisis-APT (CRAPT), is developed and tested on representative organic compounds. CRAPT incorporates (13)C compensation for refocusing inefficiency with synchronized inversion sweeps (CRISIS) pulses in combination with (1)H broadband inversion pulses to give improved compensation for variations in (1)JCH along with improved refocusing efficiency. It is shown that CRAPT gives edited (13)C spectra with only small losses in sensitivity (between 8% and 15% for strychnine, 1, menthol, 2, cholecalciferol, 3, and isotachysterol, 4), compared with basic (13)C spectra obtained on the same compounds. CRAPT also gives significantly better signal/noise than DEPTQ for nonprotonated carbons. Therefore, we conclude that CRAPT is an improvement over APT or DEPTQ or a combination of DEPT135 with a full (13)C spectrum for routine (13)C spectral editing of organic compounds.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
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 teacher head, 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".