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Ekonomiska styrformer i hälso- och sjukvården: Utvecklingslinjer och lärdomar för framtiden.
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
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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
Discrepancies between selected Pareto optimal plans and final deliverable plans in radiotherapy multi-criteria optimization
Multi-criteria optimization provides decision makers with a range of clinical choices through Pareto plans that can be explored during real time navigation and then converted into deliverable plans. Our study shows that dosimetric differences can arise between the two steps, which could compromise the clinical choices made during navigation.
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
Irradiation in a flash : Unique sparing of memory in mice after whole brain irradiation with dose rates above 100 Gy/s
This study shows for the first time that normal brain tissue toxicities after WBI can be reduced with increased dose rate. Spatial memory is preserved after WBI with mean dose rates above 100 Gy/s, whereas 10 Gy WBI at a conventional radiotherapy dose rate (0.1 Gy/s) totally impairs spatial memory.
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
X-rays can trigger the FLASH effect : Ultra-high dose-rate synchrotron light source prevents normal brain injury after whole brain irradiation in mice
This study is the first proof of concept that the FLASH effect can be triggered by X-rays. Our results show that a 10 Gy whole-brain irradiation delivered at ultra-high dose-rate with synchrotron generated X-rays does not induce memory deficit; it reduces hippocampal cell-division impairment and induces less reactive astrogliosis.
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