Publications by authors named "S Macafee"

Proton radiography has applications in patient alignment and verification procedures for proton beam radiation therapy. In this paper, we report an experiment which used 200 MeV protons to generate proton energy-loss and scattering radiographs of a hand phantom. The experiment used the first-generation proton computed tomography (CT) scanner prototype, which was installed on the research beam line of the clinical proton synchrotron at Loma Linda University Medical Center.

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A unique CMOS chip has been designed to serve as the front-end of the tracking detector data acquisition system of a pre-clinical prototype scanner for proton computed tomography (pCT). The scanner is to be capable of measuring one to two million proton tracks per second, so the chip must be able to digitize the data and send it out rapidly while keeping the front-end amplifiers active at all times. One chip handles 64 consecutive channels, including logic for control, calibration, triggering, buffering, and zero suppression.

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Background: Existing nutritional guidelines suggest that protein requirements of adults with stage five chronic kidney disease undergoing haemodialysis (HD) or peritoneal dialysis (PD) are increased as a result of protein losses during dialysis. The present review aimed to update previous guidance and develop evidence-based practice guidelines on the protein requirements of adults undergoing maintenance dialysis.

Methods: Following a PICO approach (Participants or Population, Intervention or Exposure, Comparison and Outcome), four research questions were formulated to investigate the total protein requirement and protein quality required by adults undergoing HD and PD.

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We describe a new head scanner developed for Proton Computed Tomography (pCT) in support of proton therapy treatment planning, aiming at reconstructing an accurate map of the stopping power (S.P.) in a phantom and, in the future, in patients.

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