Redesigned face mask improves “real life” aerosol delivery for nebuchamber
Bibliographic record
Abstract
The currently available facemask interface for the Nebuchamber (N) valved-holding chamber (VHC) provides a very poor seal to the face, which, on average, decreases the aerosol dose and was previously shown to increase the variability of aerosol delivery. The efficiency of a redesigned mask (RD) for the Nebuchamber with a potentially better seal was compared to the standard mask (SM) supplied with the N in a randomized real-life crossover clinical trial. Twenty children (mean age, 26 +/- 10 months) were randomized to use the Nebuchamber for 1 week with the old mask and then for another week with the newer mask, and vice versa. Filters, changed daily, inserted between the mask and the VHC, trapped the delivered drug (budesonide). The dose of budesonide was quantified by high-performance liquid chromatography (HPLC). Use of the redesigned mask improved aerosol delivery to the filter by 30%, compared to the SM (mean 28.1 +/- 7.7% of nominal dose with RD vs. 21.6 +/- 9.6% with SM, P = 0.017). The relatively high within-subject variability in aerosol delivery (36-38%) did not change, however. Facemasks are arguably the most important determinants of aerosol delivery. The newly developed RD for the Nebuchamber proved to be considerably more efficient than the SM for aerosol delivery to young children. Patient-related factors may be more important with respect to the variability observed.
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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 | 0.001 | 0.002 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.001 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.001 | 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 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".