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Abstract PurposeDiffusion encoding gradient waveforms can impartintra‐voxelandinter‐voxeldephasing owing to bulk motion, limiting achievable signal‐to‐noise and complicating multishot acquisitions. In this study, we characterize improvements in phase consistency via gradient moment nulling of diffusion encoding waveforms. MethodsHealthy volunteers received neuro () and cardiac () MRI. Three gradient moment nulling levels were evaluated: compensation for position (), position + velocity (), and position + velocity + acceleration (). Three experiments were completed: (Exp‐1) Fixed Trigger Delay Neuro DWI; (Exp‐2) Mixed Trigger Delay Neuro DWI; and (Exp‐3) Fixed Trigger Delay Cardiac DWI. Significant differences () of the temporal phase SD between repeated acquisitions and the spatial phase gradient across a given image were assessed. Resultsmoment nulling was a reference for all measures. In Exp‐1, temporal phase SD for diffusion encoding was significantly reduced with (35% oft‐tests) and (68% oft‐tests). The spatial phase gradient was reduced in 23% oft‐tests for and 2% of cases for . In Exp‐2, temporal phase SD significantly decreased with gradient moment nulling only for (83% oft‐tests), but spatial phase gradient significantly decreased with only (50% oft‐tests). In Exp‐3, gradient moment nulling significantly reduced temporal phase SD and spatial phase gradients (100% oft‐tests), resulting in less signal attenuation and more accurate ADCs. ConclusionWe characterized gradient moment nulling phase consistency for DWI. UsingM1for neuroimaging andM1 + M2for cardiac imaging minimized temporal phase SDs and spatial phase gradients.
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This content will become publicly available on September 11, 2026
A diagonal volatility basis set to assess the condensation of organic vapors onto particles
We present a “diagonal” Volatility Basis Set (dVBS) comparing gas-phase concentrations of oxygenated organic molecules (OOM) to their condensed-phase mass fractions.
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- PAR ID:
- 10645494
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Environmental Science: Atmospheres
- Volume:
- 5
- Issue:
- 9
- ISSN:
- 2634-3606
- Page Range / eLocation ID:
- 1035 to 1061
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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