Sentence examples for sphere activities from inspiring English sources

In this study, we defined the activity recovery coefficient (ARC) as the ratio between the estimated and reference sphere activities.

Generally, the TARCs were slightly overestimated for all of the spheres, but the estimated sphere activities typically remained within approximately 10% of the reference value (defined by the syringe activity measured in an activity meter and the sphere volumes).

The COV for each sphere size and hot sphere activity concentrations are shown in Table 3.

The background activity concentrations were 10, 20, 30, and 50% of the sphere activity concentration.

The total sphere activity was generally overestimated but remained within 10% of the reference activity defined by the phantom preparation.

Fig. 5 a e Recovery coefficients as a function of hot sphere size from five different hot sphere activity concentrations across all sites.

The lung residual error for the 1 8 background-to-hot sphere activity ratio was lower in mCT images (17 %) compared to mMR images (22 %) (three iterations, without TOF and/or PSF) (Fig. 5).

The reconstructed sphere activity was determined using a spherical volume of interest (VOI) with twice the diameter of the sphere used in the simulations, and from this VOI, the relative differences between the estimated activities and those defined in the simulations were calculated.

Best performance (at three iterations) of the evaluated reconstruction settings resulted in approximately the same mean hot sphere contrast on both systems and a difference of 19 percentage points (pp) in mean cold contrast, in favour of the mCT for the 1 8 background-to-hot sphere activity concentration (Table 2).

The PET NEMA image quality phantom (PTW, Freiburg, Germany) was prepared with 18F− once for each background-to-hot sphere activity concentration (1 8 and 1 4) as a part of the NEMA NU 2-2007 procedure [23], which was the NEMA protocol employed by the manufacturer at the time of these experiments.

However, small random variations in dose-calibrator sphere-activity assays marred count-rate/megabecquerel comparisons between the different sized spheres.