AAPM MEDICAL PHYSICS PRACTICE GUIDELINE 5.b: Commissioning and QA of treatment planning dose calculations-Megavoltage photon and electron beams.

The American Association of Physicists in Medicine (AAPM) is a nonprofit professional society whose primary purposes are to advance the science, education, and professional practice of medical physics. The AAPM has more than 8000 members and is the principal organization of medical physicists in the United States. The AAPM will periodically define new practice guidelines for medical physics practice to help advance the science of medical physics and to improve the quality of service to patients throughout the United States. Existing medical physics practice guidelines will be reviewed for the purpose of revision or renewal, as appropriate, on their fifth anniversary or sooner. Each medical physics practice guideline represents a policy statement by the AAPM, has undergone a thorough consensus process in which it has been subjected to extensive review, and requires the approval of the Professional Council. The medical physics practice guidelines recognize that the safe and effective use of diagnostic and therapeutic radiology requires specific training, skills, and techniques, as described in each document. Reproduction or modification of the published practice guidelines and technical standards by those entities not providing these services is not authorized. The following terms are used in the AAPM practice guidelines: Must and Must Not: Used to indicate that adherence to the recommendation is considered necessary to conform to this practice guideline. While must is the term to be used in the guidelines, if an entity that adopts the guideline has shall as the preferred term, the AAPM considers that must and shall have the same meaning. Should and Should Not: Used to indicate a prudent practice to which exceptions may occasionally be made in appropriate circumstances.

Use of bilirubin as a marker of adherence to atazanavir-based antiretroviral therapy.

We retrospectively reviewed 134 patients to evaluate atazanavir-related bilirubin elevation as an adherence marker. Using a 2 log reduction or undetectable viral load as a marker for suppression, the median bilirubin increase at first follow-up was 1.3 (0.7-2.2), versus 0.2 (-0.05-0.65) for those not suppressed. An increase in bilirubin of more than 0.4 mg/dl correctly classified 81% of patients as having successful treatment response (sensitivity 87%, specificity 63%), suggesting that bilirubin is a good adherence marker.

Structure and electrocatalysis of sputtered RuPt thin-film electrodes.

The structural and electrochemical properties of RuPt thin-film electrodes fabricated by radio frequency (rf) magnetron sputtering have been investigated. Grazing incidence X-ray diffraction data show a transition from a face-centered cubic (fcc) to hexagonal cubic-packed (hcp) structure as the Ru percentage increases. The transition occurs gradually between 32 and 58% Ru, which is significantly different from the bulk RuPt phase diagram. The catalytic activity of the thin-film electrodes for methanol oxidation shows a broad peak near 40-60% Ru, consistent with previous reports. The relationship between catalytic activity and film structure is discussed and contrasted with previous investigations.