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Purpose: We investigated the characteristics of radiation-induced current in nano-porous pellet and thin-film anodized tantalum exposed to kVp X-ray beams. We aim at developing a large area (≫cm2) thin-film radiation sensor for medical, national security and space applications. Methods: Large area (few cm2) micro-thin Ta foils were anodized and coated with a counter electrode made of conductive polymer. In addition, several types of commercial electrolytic porous tantalum capacitors were assembled and prepared for irradiation with kVp X-rays. We measured dark current (leakage) as well as transient radiation-induced currents as a function of external voltage bias. Results: Large transient currents (up to 50 nA) under X-ray irradiation (dose rate of about 3 cGy/s) were measured in Ta2O5 capacitors. Small nano-porous Ta and large-area flat Ta foil capacitors show similar current–voltage characteristic curve after accounting for different X-ray attenuation in capacitor geometry. The signal is larger for thicker capacitor oxide. A non-negligible signal for null external voltage bias is observed, which is explained by fast electron production in Ta foils. Conclusions: Anodized tantalum is a promising material for use in large-area, self-powered radiation sensors for X-ray detection and for energy harvesting. [ABSTRACT FROM AUTHOR]

Purpose: Determine the dosimetric quality and the planning time reduction when utilizing a template-based automated planning application. Methods: A software application integrated through the treatment planning system application programing interface, QuickPlan, was developed to facilitate automated planning using configurable templates for contouring, knowledge-based planning structure matching, field design, and algorithm settings. Validations are performed at various levels of the planning procedure and assist in the evaluation of readiness of the CT image, structure set, and plan layout for automated planning. QuickPlan is evaluated dosimetrically against 22 hippocampal-avoidance whole brain radiotherapy patients. The required times to treatment plan generation are compared for the validations set as well as 10 prospective patients whose plans have been automated by QuickPlan. Results: The generations of 22 automated treatment plans are compared against a manual replanning using an identical process, resulting in dosimetric differences of minor clinical significance. The target dose to 2% volume and homogeneity index result in significantly decreased values for automated plans, whereas other dose metric evaluations are nonsignificant. The time to generate the treatment plans is reduced for all automated plans with a median difference of 9′ 50″ ± 4′ 33″. Conclusions: Template-based automated planning allows for reduced treatment planning time with consistent optimization structure creation, treatment field creation, plan optimization, and dose calculation with similar dosimetric quality. This process has potential expansion to numerous disease sites. [ABSTRACT FROM AUTHOR]

Purpose: This manuscript describes the structure, management and outcomes of a multi‐institutional clinical and research medical physics residency program (Harvard Medical Physics Residency Program, or HMPRP) to provide potentially useful information to the centers considering a multi‐institutional approach for their training programs. Methods: Data from the program documents and public records was used to describe HMPRP and obtain statistics about participating faculty, enrolled residents, and graduates. Challenges associated with forming and managing a multi‐institutional program and developed solutions for effective coordination between several clinical centers are described. Results: HMPRP was formed in 2009 and was accredited by the Commission on Accreditation of Medical Physics Education Programs (CAMPEP) in 2011. It is a 3‐year therapy program, with a dedicated year of research and the 2 years of clinical training at three academic hospitals. A CAMPEP‐accredited Certificate Program is embedded in HMPRP to allow enrolled residents to complete a formal didactic training in medical physics if necessary. The clinical training covers the material required by CAMPEP. In addition, training in protons, CyberKnife, MR‐linac, and at network locations is included. The clinical training and academic record of the residents is outstanding. All graduates have found employment within clinical medical physics, mostly at large academic centers and graduates had a 100% pass rate at the oral American Board of Radiology exams. On average, three manuscripts per resident are published during residency, and multiple abstracts are presented at conferences. Conclusions: A multi‐institutional medical physics residency program can be successfully formed and managed. With a collaborative administrative structure, the program creates an environment for high‐quality clinical training of the residents and high productivity in research. The main advantage of such program is access to a wide variety of resources. The main challenge is creating a structure for efficient management of multiple resources at different locations. This report may provide valuable information to centers considering starting a multi‐institutional residency program. [ABSTRACT FROM AUTHOR]