Multiple Breath Washout MRI in the Rat Lung: Comparison of Hyperpolarized 129Xe and Perfluoropropane Gases
Bibliographic record
Abstract
Hyperpolarized 129Xe can be used with multiple breath washout (MBW) magnetic resonance imaging (MRI) to measure regional gas replacement per breath. This technique may be particularly important when monitoring lung disease progression and treatment. Fluorinated gases, such as perfluoropropane (PFP), can also measure regional gas replacement when used with MBW MRI and allows for a more accessible and affordable approach for young or diseased patients compared to hyperpolarized xenon (HP 129Xe), with potential to probe further breaths with a higher signal to noise ratio (SNR). This thesis explores a direct comparison of MBW MRI in the rat lung for HP 129Xe and PFP gases, including mapping of fractional ventilation (FV), using 2 groups of mechanically ventilated rats (healthy control and injured with bleomycin). PFP showed a significant increase in end image MBW SNR compared to hyperpolarized 129Xe. A strong positive correlation of FV was found between the gases with high repeatability.
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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 | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| 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".