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1.
PLoS One ; 19(3): e0299270, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38437196

RESUMO

The allocation of renewable energy plants, especially wind turbines, is stagnating in Germany. Although the citizens approve of the energy transition, they resist concrete local projects. In recent years, research has shown that interactive map applications support participatory planning through motivation, social interaction, and knowledge transfer. We aim to reduce biases against renewable energy (RE) and support informed decision making while accepting local responsibility. We hypothesized that finding a new gamified participation format, based on behavioral mechanisms, would strengthen the empowerment of people. To this end, we designed a dialogue tool and participation format, 'Vision:En 2040', which combines: (i) a precise target electricity yield, (ii) an interactive map showing results of people's actions, information about environmental impacts, and (iii) game rules which foster cooperation. In facilitated workshops, participants simulate the allocation of wind and photovoltaic power plants in their municipality to achieve a target electricity yield. The developed tool is based on methods of environmental planning and geoinformatics. 'Vision:En 2040' was systematically tested with a technical test and a pre-test. In addition, its impact on participants was assessed through surveys and qualitative content analysis. The evaluation results show that the tool can influence the acceptance of the energy transition in terms of attitude. Through 'Vision:En 2040', participants became aware of the community's responsibility in the energy transition and expanded their knowledge. In addition, decision makers used the workshop results to plan RE sites. Our results indicate that 'Vision:En 2040' is helpful for informal citizen participation in accelerating the energy transition.


Assuntos
Conscientização , Pesquisa Comportamental , Humanos , Fenômenos Físicos , Eletricidade , Alemanha
2.
Strahlenther Onkol ; 199(10): 936-949, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37270715

RESUMO

PURPOSE: Patients sometimes report phosphene and phantosmia during radiation therapy (RT). However, the detail features and related factors are not well understood. Our prospective study aimed to investigate the characteristics of phantosmias and phosphenes, to identify factors that influence the occurrence, intensity and hedonic (pleasantness/unpleasantness) ratings of such sensations during RT. METHODS: We included a total of 106 patients (37 women), who underwent RT in regions of the brain, ear, nose, throat (ENT), and other areas of the body for a duration of 43 ± 5 days. Medical history and treatment parameters were collected in a structured medical interview. Olfactory function was measured using the Sniffin' Stick Odor Identification Test at baseline. Phantosmia and phosphene were recorded weekly based on a self-report questionnaire. RESULTS: There were 37% of the patients experiencing phantosmias, 51% experiencing phosphenes, and 29% simultaneously experiencing both sensations. Phosphenes were typically perceived as a flashily blue, white and/or purple light, phantosmias were typically perceived as a chemical-like, metallic or burnt smell. Younger age (F = 7.81, p < 0.01), radiation in the brain region (χ2 = 14.05, p = 0.02), absence of taste problems (χ2 = 10.28, p = 0.01), and proton RT (χ2 = 10.57, p = 0.01) were related to these abnormal sensations. History of chemical/dust exposure predicted lower intensity (B = -1.52, p = 0.02) and lower unpleasantness (B = 0.49, p = 0.03) of phantosmia. In contrast, disease (tumor) duration (B = 0.11, p < 0.01), food allergy (B = 2.77, p < 0.01), and epilepsy (B = -1.50, p = 0.02) influence phosphenes intensity. Analgesics intake predicted a higher pleasantness of the phosphenes (B = 0.47, p < 0.01). CONCLUSIONS: Phantosmias and phosphenes are common during RT. The treatment settings and individual arousal level influence the occurrence, intensity and hedonic of such abnormal sensations. Phantosmias and phosphenes may involve more central neural than peripheral mechanism, and they could be elicited with activation of areas that are not regarded to be part of the olfactory or visual network.


Assuntos
Transtornos do Olfato , Olfato , Humanos , Feminino , Estudos Prospectivos , Transtornos do Olfato/etiologia , Fosfenos , Emoções
3.
Int J Radiat Oncol Biol Phys ; 117(3): 718-729, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37160193

RESUMO

PURPOSE: The development of online-adaptive proton therapy (PT) is essential to overcome limitations encountered by day-to-day variations of the patient's anatomy. Range verification could play an essential role in an online feedback loop for the detection of treatment deviations such as anatomical changes. Here, we present the results of the first systematic patient study regarding the detectability of anatomical changes by a prompt-gamma imaging (PGI) slit-camera system. METHODS AND MATERIALS: For 15 patients with prostate cancer, PGI measurements were performed during 105 fractions (201 fields) with in-room control computed tomography (CT)acquisitions. Field-wise doses on control CT scans were manually classified as whether showing relevant or non-relevant anatomical changes. This manual classification of the treatment fields was then used to establish an automatic field-wise ground truth based on spot-wise dosimetric range shifts, which were retrieved from integrated depth-dose (IDD) profiles. To determine the detection capability of anatomical changes with PGI, spot-wise PGI-based range shifts were initially compared with corresponding dosimetric IDD range shifts. As final endpoint, the agreement of a developed field-wise PGI classification model with the field-wise ground truth was determined. Therefore, the PGI model was optimized and tested for a subcohort of 131 and 70 treatment fields, respectively. RESULTS: The correlation between PGI and IDD range shifts was high, ρpearson = 0.67 (p < 0.01). Field-wise binary PGI classification resulted in an area under the curve of 0.72 and 0.80 for training and test cohorts, respectively. The model detected relevant anatomical changes in the independent test cohort, with a sensitivity and specificity of 74% and 79%, respectively. CONCLUSIONS: For the first time, evidence of the detection capability of anatomical changes in prostate-cancer PT from clinically acquired PGI data is shown. This emphasizes the benefit of PGI-based range verification and demonstrates its potential for online-adaptive PT.


Assuntos
Neoplasias da Próstata , Terapia com Prótons , Masculino , Humanos , Terapia com Prótons/métodos , Próstata/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Radiometria , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos
4.
Clin Transl Radiat Oncol ; 38: 111-116, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36407488

RESUMO

Background and purpose: Motion mitigation is of crucial importance in particle therapy (PT) of patients with abdominal tumors to ensure high-precision irradiation. Magnetic resonance imaging (MRI) is an excellent modality for target volume delineation and motion estimation of mobile soft-tissue tumors. Thus, the aims of this study were to develop an MRI- and PT-compatible abdominal compression device, to investigate its effect on pancreas motion reduction, and to evaluate patient tolerability and acceptance. Materials and methods: In a prospective clinical study, 16 patients with abdominal tumors received an individualized polyethylene-based abdominal corset. Pancreas motion was analyzed using time- and phase resolved MRI scans (orthogonal 2D-cine and 4D MRI) with and without compression by the corset. The pancreas was manually segmented in each MRI data set and the population-averaged center-of-mass motion in inferior-superior (IS), anterior-posterior (AP) and left-right (LR) directions was determined. A questionnaire was developed to investigate the level of patient acceptance of the corset, which the patients completed after acquisition of the planning computed tomography (CT) and MRI scans. Results: The corset was found to reduce pancreas motion predominantly in IS direction by on average 47 % - 51 % as found in the 2D-cine and 4D MRI data, respectively, while motion in the AP and LR direction was not significantly reduced. Most patients reported no discomfort when wearing the corset. Conclusion: An MRI- and PT-compatible individualized abdominal corset was presented, which substantially reduced breathing-induced pancreas motion and can be safely applied with no additional discomfort for the patients. The corset has been successfully integrated into our in-house clinical workflow for PT of tumors of the upper abdomen.

5.
PLoS One ; 16(11): e0260302, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34818356

RESUMO

A key challenge of environmental planning is to craft recommendations for future sustainable spatial development amid ubiquitous uncertainties. This paper aims to explore how different data uncertainties, usually unknown to the planner, may influence environmental planning recommendations. We apply a case study-based approach, in which we provide three illustrative examples of how data with different kinds and levels of uncertainty affect environmental assessments and, by that, the decision-support provided by environmental planning. The cases stem from different spatial levels in Germany and consider 'Regional soil-based climate change mitigation' in the region of Hannover, 'State-wide habitat conservation siting' in the federal state of Saxony-Anhalt, and 'National renewable energy planning'. Based on the three examples, we discuss implications for planning practice and derive recommendations for further research. The three cases studies illustrate the substantial effects of data uncertainty on environmental assessments and planning recommendations derived from those results. We identify four problem constellations of dealing with data uncertainty in environmental planning that relate to the severeness of uncertainty impacts, the responsibility of the decision-maker, and the kinds of impacts that wrong decisions may have. We close with recommendations for further research, among others to develop robust and pragmatic methods for identifying the uncertainty levels in environmental data and assessment results.


Assuntos
Recursos Naturais , Desenvolvimento Sustentável , Mudança Climática , Planejamento Ambiental/tendências , Alemanha , Desenvolvimento Sustentável/tendências , Incerteza
6.
Int J Radiat Oncol Biol Phys ; 111(4): 1033-1043, 2021 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-34229052

RESUMO

PURPOSE: Uncertainty in computed tomography (CT)-based range prediction substantially impairs the accuracy of proton therapy. Direct determination of the stopping-power ratio (SPR) from dual-energy CT (DECT) has been proposed (DirectSPR), and initial validation studies in phantoms and biological tissues have proven a high accuracy. However, a thorough validation of range prediction in patients has not yet been achieved by any means. Here, we present the first systematic validation of CT-based proton range prediction in patients using prompt gamma imaging (PGI). METHODS AND MATERIALS: A PGI slit camera system with improved positioning accuracy, using a floor-based docking station, was used. Its overall uncertainty for range prediction validation was determined experimentally with both x-ray and beam measurements. The accuracy of range prediction in patients was determined from clinical PGI measurements during hypofractionated treatment of 5 patients with prostate cancer - in total 30 fractions with in-room control-CTs. For each pencil-beam-scanning spot, the range shift was obtained by comparing the PGI measurement to a control-CT-based PGI simulation. Three different SPR prediction approaches were applied in simulations: a standard CT-number-to-SPR conversion (Hounsfield look-up table [HLUT]), an adapted HLUT (DECT optimized), and DirectSPR. The spot-wise weighted mean range shift from all spots served as a measure for the accuracy of the respective range prediction approach. RESULTS: A mean range prediction accuracy of 0.0% ± 0.5%, 0.3% ± 0.4%, and 1.8% ± 0.4% was obtained for DirectSPR, adapted HLUT, and standard HLUT, respectively. The overall validation uncertainty of the second-generation PGI slit camera is about 1 mm (2σ) for all approaches, which is smaller than the range prediction uncertainty for deep-seated tumors. CONCLUSIONS: For the first time, range prediction accuracy was assessed in clinical routine using PGI range verification in prostate cancer treatments. Both DECT-derived range prediction approaches agree well with the measured proton range from PGI verification, whereas the standard HLUT approach differs relevantly. These results endorse the recent reduction of clinical safety margins in DirectSPR-based treatment planning in our institution.


Assuntos
Neoplasias da Próstata , Terapia com Prótons , Humanos , Masculino , Imagens de Fantasmas , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia , Prótons , Planejamento da Radioterapia Assistida por Computador , Tomografia Computadorizada por Raios X
7.
Radiother Oncol ; 133: 28-34, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30935578

RESUMO

BACKGROUND AND PURPOSE: Oesophageal mobility relative to bony anatomy is a major source of geometrical uncertainty in proton radiotherapy of oesophageal carcinoma. To mitigate this uncertainty we investigated the use of implanted fiducial markers for direct target verification in terms of safety, visibility, and stability. MATERIALS AND METHODS: A total of 19 helical gold markers were endoscopically implanted in ten patients. Their placement at the proximal and distal tumour borders was compared to tumour demarcations derived from [18F]Fluorodeoxyglucose positron emission tomography, their visibility quantified via the contrast-to-noise ratio on daily orthogonal X-ray imaging, and their mobility relative to bony anatomy analysed by means of retrospective triangulation. RESULTS: Marker implantation proceeded without complications, but the distal tumour border could not be reached in two patients. Marker locations corresponded reasonably well with metabolic tumour edges (mean: 5.4 mm more distally). Marker visibility was limited but mostly sufficient (mean contrast-to-noise ratio: 1.5), and sixteen markers (84%) remained in situ until the end of treatment. Overall, marker excursions from their planned position were larger than 5(10) mm in 59(17)% of all analysed fractions. On one occasion severe target displacement was only identified via markers and was corrected before treatment delivery. CONCLUSION: Implanted helical gold fiducial markers are a safe and reliable method of providing target-centric positioning verification in proton beam therapy of oesophageal carcinoma.


Assuntos
Neoplasias Esofágicas/radioterapia , Marcadores Fiduciais , Terapia com Prótons/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Idoso , Estudos de Coortes , Neoplasias Esofágicas/diagnóstico por imagem , Fluordesoxiglucose F18 , Ouro , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons/métodos , Prótons , Compostos Radiofarmacêuticos , Planejamento da Radioterapia Assistida por Computador/instrumentação , Radioterapia Guiada por Imagem/instrumentação , Radioterapia Guiada por Imagem/métodos , Estudos Retrospectivos
8.
Radiother Oncol ; 118(2): 232-7, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26774764

RESUMO

BACKGROUND AND PURPOSE: To improve precision of particle therapy, in vivo range verification is highly desirable. Methods based on prompt gamma rays emitted during treatment seem promising but have not yet been applied clinically. Here we report on the worldwide first clinical application of prompt gamma imaging (PGI) based range verification. MATERIAL AND METHODS: A prototype of a knife-edge shaped slit camera was used to measure the prompt gamma ray depth distribution during a proton treatment of a head and neck tumor for seven consecutive fractions. Inter-fractional variations of the prompt gamma profile were evaluated. For three fractions, in-room control CTs were acquired and evaluated for dose relevant changes. RESULTS: The measurement of PGI profiles during proton treatment was successful. Based on the PGI information, inter-fractional global range variations were in the range of ±2 mm for all evaluated fractions. This is in agreement with the control CT evaluation showing negligible range variations of about 1.5mm. CONCLUSIONS: For the first time, range verification based on prompt gamma imaging was applied for a clinical proton treatment. With the translation from basic physics experiments into clinical operation, the potential to improve the precision of particle therapy with this technique has increased considerably.


Assuntos
Carcinoma Adenoide Cístico/radioterapia , Raios gama/uso terapêutico , Neoplasias de Cabeça e Pescoço/radioterapia , Terapia com Prótons/métodos , Carcinoma Adenoide Cístico/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
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