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• Design of a radiobiology facility based on a laser-driven ion beam source. • Geant4 based simulation tool (BDSIM) verified the beam optics design. • BDSIM determined the energy deposition profile in the end station. • Simulations confirmed 15 MeV as optimal beam energy. The Centre for the Clinical Application of Particles' Laser-hybrid Accelerator for Radiobiological Applications (LhARA) facility is being studied and requires simulation of novel accelerator components (such as the Gabor lens capture system), detector simulation and simulation of the ion beam interaction with cells. The first stage of LhARA will provide protons up to 15 MeV for in vitro studies. The second stage of LhARA will use a fixed-field accelerator to increase the energy of the particles to allow in vivo studies with protons and in vitro studies with heavier ions. BDSIM, a Geant4 based accelerator simulation tool, has been used to perform particle tracking simulations to verify the beam optics design done by BeamOptics and these show good agreement. Design parameters were defined based on an EPOCH simulation of the laser source and a series of mono-energetic input beams were generated from this by BDSIM. The tracking results show the large angular spread of the input beam (0.2 rad) can be transported with a transmission of almost 100% whilst keeping divergence at the end station very low (<0.1 mrad). The legacy of LhARA will be the demonstration of technologies that could drive a step-change in the provision of proton and light ion therapy (i.e. a laser source coupled to a Gabor lens capture and a fixed-field accelerator), and a system capable of delivering a comprehensive set of experimental data that can be used to enhance the clinical application of proton and light ion therapy. [ABSTRACT FROM AUTHOR]

We aimed to investigate the correlation between sonographic diagnosis of adenomyosis and placental associated obstetrical complications. A retrospective cohort of patients referred for a targeted ultrasound due to complaints associated with endometriosis/adenomyosis over 12 years (2010-2022) period. The study group comprised patients with adenomyosis sonographic features and the control group included patients with normal sonographic features. Patients diagnosed with endometriosis, uterine fibroids, uterine anomalies, and patients whose mode of conception relied on assisted reproduction technologies were excluded. All images were revised for diagnosis of adenomyosis by an ultrasound specialist. Cases were included if performed up to 5 years from the index birth. The primary outcome was a composite outcome of placental-associated adverse outcomes (preterm labor, small for gestational age fetus, hypertensive disorders of pregnancy, placental abruption, and postpartum hemorrhage). N/A. A total of 93 patients diagnosed with adenomyosis and 113 controls were included in the study. There were no clinically significant differences between the groups regarding patients' demographic characteristics. N/A. The adenomyosis group had a significantly higher rate of placental-associated adverse complications than controls (28% vs. 11% p<0.01). Furthermore, when examining obstetrical complications separately, preterm labor (12% vs. 4.4% p<0.05) and hypertensive disorders of pregnancy (11% vs. 2.7% p<0.05) were significantly increased in the adenomyosis patients compared to controls. A higher tendency of cesarean delivery (33% vs. 22%, p<0.072) and placental abruption (3% vs. 0%, p<0.09) was also demonstrated in the research group. Adenomyosis was independently significantly associated with placental-associated adverse obstetrical outcomes. Future prospective studies may establish the correlation between specific sonographic features of adenomyosis and the quality of placental function. [ABSTRACT FROM AUTHOR]

Pediatric lung transplantation is an infrequent, but potentially life-saving procedure for patients with end-stage pulmonary disease. While survival has been increasing over the last decades, there is a lack of data regarding long-term survivors after pediatric lung. The Vienna transplant center is unique in having a high re-transplant rate in children, leading to a high median overall survival with a large number of long-term survivors. Aim of the present retrospective single-center study was to describe the post-transplant organ function, survival, medical complications and social status of patients that survived at least 5 years after lung transplantation in pediatric age. Long term outcome of 30 pediatric lung transplant recipients was assessed retrospectively. Primary outcome contained medical status five years after transplantation (growth, BMI, lung function), complications (osteopenia, diabetes mellitus, post-transplant malignomas, psychiatric and neurological complications) five or more years after transplantation including educational status, occupation and living situation. Secondary outcome contained association of pre-transplant patient specific parameters to post transplant outcome. Out of the 73 pediatric patients, who underwent lung transplantation between 1993 and 2013 at Medical University Vienna, 30 patients survived at least 5 years after transplantation. Median survival of these patients was 192.3 months, 10-year and 15-years survival 85% and 54%, respectively. Mean FEV1%pred 5 years after transplantation was 61%, after 10 years 54%. A statistically significant increase of the median BMI percentile rank from time of transplantation to five years post transplantation was observed. From 1993 to 2002 the 10-year survival rate was 63%, whereas from 2003 to 2013 it was 100%, underlining the improvement in pediatric lung transplantation. No significant differences could be detected analyzing the influence of specific parameters (e.g. gender, underlying disease, age) on survival. We did not only observe a remarkably high long term survival rate, but also very satisfying results regarding health state in pediatric lung transplant recipients surviving at least five years after transplantation. Complications are considerable, however most importantly the majority of complications is temporary and/or are manageable. [ABSTRACT FROM AUTHOR]

Abstract: A new method of synthesizing spherical nanoparticles with photoluminescent spinel structures using a CO2 laser co-vaporization technique (CoLAVA) is presented. The method applies homogeneous mixtures of oxidic precursors such as Al2O3, SrO and Eu2O3 and allows the fabrication of quantities exceeding 10gh−1. During the CoLAVA process, the educt oxides are reacted by a gas phase condensation yielding amorphous spherical particles with diameters ranging from 10 to 100nm. The as-prepared materials exhibit red emission at 625nm (1.98eV) due to the incorporated Eu3+. Temperature treatment up to 1200°C under a reducing atmosphere yielded crystalline particles of the same size, which were slightly sintered. These particles consisted of >90wt.% SrAl2O4 with minor fractions of Sr3Al2O6 and SrCO3. The amount of the SrAl2O4 spinel increased with increasing temperature, whereas the accompanying phases were decreased. A strong green emission centered at 525nm (2.36eV) detected at RT was observed at an onset temperature of 900°C, which is due to the presence of Eu2+ in the crystal lattice of SrAl2O4. The red emission was not observed at higher annealing temperatures. The CoLAVA method represents a fast and facile route for the fabrication of nano- to microstructured phosphor materials for a variety of engineering applications. [Copyright &y& Elsevier]

Abstract: Gamma aminobutyric acid (GABA) is the major inhibitory neurotransmitter in the human brain. It plays a decisive role in a variety of nervous system disorders, such as anxiety disorders, epilepsy, schizophrenia, insomnia, and many others. The reproducibility of GABA quantification results obtained with a single-voxel spectroscopy J-difference editing sequence with Point Resolved Spectroscopy localization (MEGA-PRESS) was determined on a 3.0 Tesla MR scanner in healthy adults. Eleven volunteers were measured in long- and short-term intervals. Intra- and inter-subject reproducibility were evaluated. Internal referencing of GABA+ to total creatine (tCr) and water (H2O), as well as two different post-processing methods for the evaluation (signal integration and time-domain fitting) were compared. In all subjects lower coefficient of variation and therefore higher reproducibility can be observed for fitting compared to integration. The GABA+/tCr ratio performs better than the GABA+/H2O ratio or GABA+ without internal referencing for both fitting and integration (GABA+/tCr: 13.3% and 17.0%; GABA+/H2O: 15.0% and 17.8%; GABA+: 19.2% and 21.7%). Four-day measurements on three subjects showed higher intra- than inter-subject reproducibility (GABA+/tCr ∼10–12%). With a coefficient of variation of about 13% for inter-subject and 10–12% for intra-subject variability of GABA+/tCr, this technique seems to be a precise tool that can detect GABA confidently. The results of this study show the reproducibility limitations of GABA quantification in vivo, which are necessary for further clinical studies. [Copyright &y& Elsevier]

Summary: Background: Defects in the buttock region are frequent indications for plastic surgery and are caused by various mechanisms. Therefore, different flaps were introduced and are well established. However, all of them have their limitations in reconstruction because of their restricted arc of rotation. Hence, we indicated the use of the local fasciocutaneous infragluteal (FCI) flap for reconstruction of such defects in the buttock region. Methods: In a series of 14 patients, three of them being paraplegics, the authors used 15 local FCI flaps to cover defects in the buttock region. The defects were caused by pressure sores, pilonidal sinus infection with recurrence, an adenocarcinoma of the gluteal region, a massive abscess after intramuscular gluteal injection, lipodystrophy of the lateral gluteal region and by multiple operations after an infection of implanted hip-joint prosthesis. Results: The median dimension of the flaps was 177cm2. Fourteen of the 15 flaps healed uneventfully. In one patient, a re-mobilisation of the flap was necessary after a minor, distal-flap necrosis. Closure of the donor site was possible in all patients without further trouble. One patient needed a second local FCI flap because of a new pressure sore on the contralateral sacral region. Conclusions: The FCI flap is not only a versatile and reliable free flap with different indications, but is also a good alternative as a local flap for defect reconstruction in the whole buttock region, as demonstrated in this study for the first time. It can be raised as a sensate flap without restrictions of mobility in ambulatory patients. The donor-site morbidity is minimal, and options for future flaps of the gluteal region are preserved. [Copyright &y& Elsevier]

Abstract: Objectives: Sixty three healthy subjects were measured to assess dependence of brain metabolites on age using short- and long echo time spectroscopy in different brain regions. Material and methods: Younger and elderly humans were measured with long echo time (TE=135ms) 3D-MR-spectroscopic imaging (MRSI) (10 subjects) and with ultra-short echo (TE=11ms) time 2D-MRSI (7 subjects). In addition, results from single voxel 1H-spectroscopy (TE=20ms) of two cohorts of 46 healthy subjects were retrospectively correlated with age. Results: 3D-MR SI revealed reduced NAA/Cr in the older group in the frontal lobe (−22%; p <0.01), parietal lobe (−28%; p <0.01) and semiovale (−9%; p <0.01) compared to the younger group. Cho/Cr was elevated in the semiovale (+35%; p <0.01) and in the n. lentiformis (+42%; p <0.01) in the older group. NAA/Cho was reduced in all regions measured, except the thalamus, in the older group compared to the younger group (from −21 to −49%; p <0.01). 2D-MRSI revealed decreased total NAA (−3.1% per decade; p <0.01) and NAA/Cr (−3.8% per decade; p <0.01), increased total Cho (+3.6% per decade; p <0.01) and Cho/Cr (+4.6% per decade; p <0.01) and increased total myo-Inositol (mI, +4.7% per decade; p <0.01) and mI/Cr (+5.4% per decade; p <0.01) and decreased NAA/Cho (−8% per decade; p <0.01) in semiovale WM. Results from single voxel spectroscopy revealed a significantly negative correlation of NAA/Cho in frontal (−13% per decade; p <0.01) and in temporal lobe (−7.4% per decade; p <0.01) as well as increased total Cr (10% per decade; p <0.01) in frontal lobe. Other results from single voxel measurements were not significant, but trends were comparable to that from multivoxel spectroscopy. Conclusion: Age-related changes measured with long echo time and short echo time 1H-MRS were comparable and cannot, therefore, be caused by different T2 relaxation times in young and old subjects, as suggested previously. [Copyright &y& Elsevier]

Volunteer plants of oilseed rape (Brassica napus L.) from persistent seeds in soil can affect subsequent crops. Apart from the agricultural disadvantages, the environment and the marketing of the seeds may also be affected, particularly if plants with special ingredients or genetically modified (gm) plants are grown. In order to investigate the influence of soil cultivation and genotype on seed persistence and gene flow via volunteers, a field experiment was set up testing four tillage treatments and two cultivars in a split-plot design. The cultivars tested were near-isogenic to two gm cultivars. To simulate harvesting losses, 10 000 seeds m−2 were broadcast on a soil in July. The subsequent tillage treatments were combinations of immediate or delayed stubble tillage by a rotary tiller, primary tillage with plough or cultivator, or zero tillage. Over the following year, the fate of the seeds was determined. Immediate stubble tillage with following cultivator or plough resulted in 586 resp. 246 seeds m−2 in the soil seed bank. After delayed stubble tillage with following plough, 76 seeds m−2 were found, and no soil seed bank was built up in the zero tillage treatment. Nevertheless, in the zero tillage treatment, several robust volunteer plants survived the herbicide application before the direct drilling in autumn until following spring. In the zero tillage treatment and in the cultivator treatment, 0.19 volunteers m−2 resp. 0.06 volunteers m−2 flowered simultaneously to ordinarily sown oilseed rape in the following crop of winter wheat and produced 73 resp. 18 seeds m−2. Delayed stubble tillage reduced the risk of gene escape via the soil seed bank, while zero tillage resulted in the highest risk of gene escape by pollen and by production of a new generation of seeds. In terms of a labelling threshold for gm food this number of seeds would be below the threshold of 0.9% of transgenic parts in conventially bred food or feed. [Copyright &y& Elsevier]

Proffered Papers: Proffered papers 27: Novel technologies OC-0563: Hypoxia suppresses radiation-induced tumor immunogenicity in 3D breast cancer models S. Gruber, M. Charpentier, E. Wennerberg, S. Van Nest, S. Demaria. [Extracted from the article]

In recent decades, pediatric lung transplantation has developed into a well-accepted therapy for children and adolescents as ultimate ratio for terminal lung diseases. Although quality of life is an essential goal for a transplantation, only few data on this topic have been published yet. This study uses a standardized questionnaire to examine the health-related quality of life of patients who were lung transplanted at the Medical University of Vienna during childhood and adolescence. In this single-center cross-sectional study, 19 patients aged 8 to 40 were included in the study. The Euroqol-questionnaire and a self-designed questionnaire for information on school attendance, employment and housing situation were used. Pediatric patients waiting for lung transplantation served as control group. Pre- and post-transplant parameters were assessed for a potential influence on quality of life. The survey was done between November 2016 and October 2018. We demonstrated an improvement of quality of life after lung transplantation, as shown by a mean Euroqol Score of 1 (0-1) and a mean VAS score of 92 (0-100). The results were comparable to published data in healthy adults (Euroqol 0,96, VAS 87) and significantly better compared to our control group on the waiting list (Euroqol 0,43, VAS 68, both p<0,01). Employment rate also improved from 33 to 71%. Complication rates (pulmonary, nephrological, hepatological, neurological, psychiatric, diabetes mellitus) increased over time, with many of these complications correlating with a reduction in quality of life, especially the pulmonary parameters. Quality of life was found to correlate negatively with time since transplantation, however, scores after five years still exceeded those of patients on the waiting list. The results confirm a good quality of life after pediatric lung transplantation. [ABSTRACT FROM AUTHOR]

• A new method is proposed to visualize local sublimation front velocities. • Neutron radiography and tomography is a valuable tool to investigate freeze-drying. • Radial drying fronts of each particle were observed. • A planar drying front evolving from the bottom of the bed could be observed. With this study it was possible for the first time to visualize local sublimation front velocities of particle beds with neutron radiography and tomography. Few theoretical studies exist on the freeze-drying behavior of particle beds, but no experimental validation of the models exists basically due to the limits of traditional measurement techniques. The study was conducted at the neutron imaging facility ANTARES at the Heinz Maier Leibnitz Centre. Maltodextrin particles (x = 3550 µm) with different solid concentrations (c = 0.05 w/w; c = 0.2 w/w) were investigated. For the radiography measurements, it is shown that a main sublimation front evolves from the bottom to the top of the bed. Tomography measurements (for particles with c = 0.05 w/w) confirmed the formation of radial drying fronts throughout the bed in addition to the main sublimation front. In general, both methods show overall good agreement and will be a valuable tool for further investigations. [ABSTRACT FROM AUTHOR]

Abstract The behavior of ice in frozen rock masses is an important control on rock slope stability but the knowledge of the formation, extent and evolution of ice-filled fractures in steep bedrock permafrost is limited. Therefore, this study aims at characterizing the site specific ambient seismic vibration recorded at the Matterhorn Hörnligrat fieldsite over the course of more than three years. The observed normal mode resonance frequencies vary seasonally with four distinct phases: persistent decrease during summer (phase I), rapid increase during freezing (phase II), trough-shaped pattern in winter (phase III) and a sharp peak with a rapid decay during the melting/thawing season (phase IV). The relation between resonance frequency and rock temperature exhibits an annually repeated pattern with hysteretic behavior. The link between resonance frequency, fracture width and rock temperature indicates that irreversible fracture displacement is dominant in summer periods with low resonance frequency. These findings suggest that the temporal variations in resonance frequencies are linked to the formation and melt of ice-fill in bedrock fractures. Highlights • Over three years of recorded ambient seismic vibrations in bedrock permafrost. • Distinct seasonal patterns in resonance frequency were observed. • Obtained resonance frequency agrees with the resonance of cantilever beam. • Variations of ice-fill in fractures change the geometry of the resonating rock mass. • Temporal variations in resonance frequency are linked to ice-fill in fractures. [ABSTRACT FROM AUTHOR]

Abstract: Proton magnetic resonance spectroscopic imaging is a non-invasive diagnostic tool for the investigation of cancer metabolism. As an adjunct to morphologic and dynamic magnetic resonance imaging, it is routinely used for the staging, assessment of treatment response, and therapy monitoring in brain, breast, and prostate cancer. Recently, its application was extended to other cancerous diseases, such as malignant soft-tissue tumours, gastrointestinal and gynecological cancers, as well as nodal metastasis. In this review, we discuss the current and evolving clinical applications of proton magnetic resonance spectroscopic imaging. In addition, we will briefly discuss other evolving techniques, such as phosphorus magnetic resonance spectroscopic imaging, sodium imaging and diffusion-weighted imaging in cancer assessment. [Copyright &y& Elsevier]