Head movement during a dynamic brain PET/CT imaging results in mismatch between CT and dynamic PET images. It can cause artifacts in CT-based attenuation corrected PET images, thus affecting both the qualitative and quantitative aspects of the dynamic PET images and the derived parametric images. In this study, we developed an automated retrospective image-based movement correction (MC) procedu...

introduction based on task group no. 43 (tg-43u1) recommendations, water phantom is proposed as a reference phantom for the dosimetry of brachytherapy sources. the experimental determination of tg-43 parameters is usually performed in water-equivalent solid phantoms. the purpose of this study was to determine the conversion factors for equalizing solid phantoms to water. materials and methods t...

UNLABELLED The limited spatial resolution of SPECT scanners does not allow an exact measurement of the local radiotracer concentration in brain tissue because partial-volume effects (PVEs) underestimate concentration in small structures of the brain. The aim of this study was to determine which brain structures show greater influence of PVEs in SPECT studies on healthy volunteers and to investi...

Blood samples from 145 Black-crowned Night-heron (Nycticorax nycticorax, BCNH) chicks (mean age 3 weeks) were taken from four island colonies (Goose (2004), Canarsie Pol (2005), Hoffman (2004 and 2005) and North Brother (2004 and 2005)) in New York Harbor in 2004 and 2005 to establish baseline health reference ranges for this species and to compare health indices of birds reared on different is...

The notion of gregarious cycles in complete multipartite graphs was introduced by Billington and Hoffman in 2003 and was modified later by Billington, Hoffman, and Rodger and by Billington, Smith, and Hoffman. In this paper, we propose a new definition of gregarious cycles in complete multipartite graphs which generalizes all of the three definitions. With our definition, we can consider gregar...