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Design thinking in the organizational development of a 350-years old university library

The purpose of this conference paper is to showcase how the user experience (UX) methodology of design thinking can facilitate organizational change processes in situations of multiple and often conflicting values and opinions in university libraries. The paper also elaborates on the application of design thinking under both normal circumstances and Covid-19 restrictions. The conference paper is b

High dose-per-pulse electron beam dosimetry : Usability and dose-rate independence of EBT3 Gafchromic films: Usability

Purpose: The aim of this study was to assess the suitability of Gafchromic EBT3 films for reference dose measurements in the beam of a prototype high dose-per-pulse linear accelerator (linac), capable of delivering electron beams with a mean dose-rate (Dm) ranging from 0.07 to 3000 Gy/s and a dose-rate in pulse (Dp) of up to 8 × 106 Gy/s. To do this, we evaluated the overall uncertainties in EBT3

SU‐E‐T‐809 : A Grading‐Study Based Tool to Assist in the Choice of Treatment Modality

Purpose: It is common for radiation oncologists (ROs) today to have a mixed arsenal of radiotherapy treatment modalities at their disposal. To optimize a clinic's use of its different treatment modalities, while at the same time giving every patient an optimal treatment, is not a trivial task. The purpose of this study was to give ROs a tool to choose between available modalities. This would help

High dose-per-pulse electron beam dosimetry -A model to correct for the ion recombination in the advanced markus ionization chamber

Purpose: The purpose of this work was to establish an empirical model of the ion recombination in the Advanced Markus ionization chamber for measurements in high dose rate/dose-per-pulse electron beams. In addition, we compared the observed ion recombination to calculations using the standard Boag two-voltage-analysis method, the more general theoretical Boag models, and the semiempirical general

Analysis of the treatment plan evaluation process in radiotherapy through eye tracking

Background and purpose: Treatment plan evaluation is a clinical decision-making problem that involves visual search and analysis in a contextually rich environment, including delineated structures and isodose lines superposed on CT data. It is a two-step process that includes visual analysis and clinical reasoning. In this work, we used eye tracking methods to gain more knowledge about the treatme

High dose-per-pulse electron beam dosimetry : Commissioning of the Oriatron eRT6 prototype linear accelerator for preclinical use: Commissioning

Purpose: The Oriatron eRT6 is an experimental high dose-per-pulse linear accelerator (linac) which was designed to deliver an electron beam with variable dose-rates, ranging from a few Gy/min up to hundreds of Gy/s. It was built to study the radiobiological effects of high dose-per-pulse/dose-rate electron beam irradiation, in the context of preclinical and cognitive studies. In this work, we repo

A treatment planning comparison of contemporary photon-based radiation techniques for breast cancer

Background and purpose: Adjuvant radiation therapy (RT) of the whole breast (WB) is still the standard treatment for early breast cancer. A variety of radiation techniques is currently available according to different delivery strategies. This study aims to provide a comparison of six treatment planning strategies commonly adopted for breast-conserving adjuvant RT and to use the Pareto concept in

The Advantage of FLASH Radiotherapy Confirmed in Mini-pig and Cat-cancer Patients

Purpose: Previous studies using FLASH radiotherapy (RT) in mice showed a marked increase of the differential effect between normal tissue and tumors. To stimulate clinical transfer, we evaluated whether this effect could also occur in higher mammals. Experimental Design: Pig skin was used to investigate a potential difference in toxicity between irradiation delivered at an ultrahigh dose rate call

Long-term neurocognitive benefits of FLASH radiotherapy driven by reduced reactive oxygen species

Here, we highlight the potential translational benefits of delivering FLASH radiotherapy using ultra-high dose rates (>100 Gy·s−1). Compared with conventional dose-rate (CONV; 0.07–0.1 Gy·s−1) modalities, we showed that FLASH did not cause radiation-induced deficits in learning and memory in mice. Moreover, 6 months after exposure, CONV caused permanent alterations in neurocognitive end points, wh

Dosimetric and preparation procedures for irradiating biological models with pulsed electron beam at ultra-high dose-rate

Purpose: Preclinical studies using a new treatment modality called FLASH Radiotherapy (FLASH-RT) need a two-phase procedure to ensure minimal uncertainties in the delivered dose. The first phase requires a new investigation of the reference dosimetry lying outside the conventional metrology framework from national metrology institutes but necessary to obtain traceability, repeatability, and stabil

Exploration of clinical preferences in treatment planning of radiotherapy for prostate cancer using Pareto fronts and clinical grading analysis

Introduction: Radiotherapy treatment planning is a multi-criteria problem. Any optimization of the process produces a set of mathematically optimal solutions. These optimal plans are considered mathematically equal, but they differ in terms of the trade-offs involved. Since the various objectives are conflicting, the choice of the best plan for treatment is dependent on the preferences of the radi

Understanding High-Dose, Ultra-High Dose Rate, and Spatially Fractionated Radiation Therapy

The National Cancer Institute's Radiation Research Program, in collaboration with the Radiosurgery Society, hosted a workshop called Understanding High-Dose, Ultra-High Dose Rate and Spatially Fractionated Radiotherapy on August 20 and 21, 2018 to bring together experts in experimental and clinical experience in these and related fields. Critically, the overall aims were to understand the biologic