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The effective sound speed gradient is used to describe the meteorological conditions during sound measurements at roads and railways. Meteorological parameters were assessed up to a height of 10 m. The sound level differences between a reference point close to the passing vehicles and at distances of 100–500 m from motorways and railway tracks were determined. These differences were found to correlate well with the effective sound speed gradient determined from the measured temperature and wind speed gradients which follow the day/night cycle as a result of the reversing air temperature gradient, incoming solar radiation and wind conditions. The correlation with sound level differences can be approximated by an S-shaped function which is constant for large positive or negative gradients of the effective sound speed. These threshold values are a consequence of the local meteorological and attenuation conditions. The analysis shows that large effective sound speed gradients are mainly a result of the wind conditions whereas gradients without a substantial wind speed contribution are low and a result of the temperature gradient. In the distance range between 150 m and 250 m, the meteorological influences cause a level increase of 3–4 dB(A) for downward refracted sound rays (favourable sound propagation) compared to a situation without meteorological influence (effective sound speed gradient of zero). In the same distance range, meteorological conditions cause a maximum sound level attenuation of 5–10 dB(A) for upward curved sound rays (unfavourable sound propagation).

Context: Noise indicators are the basis to describe noise exposure–effect relationships. The assessment of these noise indicators in field studies includes various uncertainties, so that the true values differ from the determined values used for establishing curve fits. If the relationship between a noise indicator and its effect is nonlinear, uncertainties of the noise indicator modify the observed exposure–effect relationships. Materials and Methods: The determination of an exposure-relationship curve fit within a field study was simulated based on the assumption of a given true exposure-relationship without uncertainties and normal distributed uncertainties for the observed noise indicator used for the statistics. Results: In case of an upward curvature of the exposure–effect relationship, the uncertainty for the noise indicator value leads to an asymmetric effect for the curve fit. Uncertainties of the same amount of over- or underestimation will not result in an identical over- or underestimation of the observed effect. A simulation of this effect shows an increased curvature of the observed curve fit, with overestimated exposure–effect relationships. Conclusion: Although linear exposure–effect curves are not observed with a systematic shift, quadratic, cubic, and exponential curve forms include a systematic uncertainty in the presented exposure–response curve. If such curves are used to define threshold levels to limit harmful effects of noise, no further uncertainty margins are needed for those situations where the calculated noise indicator uncertainties are equal or lower than those present in the underlying field study.

Context: The aim of this study was to verify the contributing effect in the cases of combined road traffic noise and railroad traffic noise on total noise annoyance. Materials and Methods: After opening the four-track railway of the Lower Inn Valley Route in Austria, an evaluation study was conducted by an interview survey (n=1003). The data of this survey included answers on annoyance caused by railroad, road traffic noise and total annoyance as well as self-evaluated noise sensitivity. Results: When annoyance is only related to one of these sources, a 10% share of highly annoyed persons was observed at 59 dB for road noise and 60 dB for railroad noise. The annoyance model including both noise sources with a coefficient of 0.145 for road noise, 0.034 for railroad noise and 0.431 for noise sensitivity (all p-values < 0.01) showed a regression coefficient R2 of 0.299. The presence of road background noise did not influence the annoyance on railway noise. Conclusion: The combined influence of road and railway noise showed an increase of total annoyance.

Land-use categories are often used to define the exposure limits of national environmental noise policies. Often different guideline values for noise are applied for purely residential areas versus residential areas with mixed-use. Mixed-use includes living plus limited activities through crafts, commerce, trade, agriculture, and forestry activities. This differentiation especially when rating noise from road, railway, and air traffic might be argued by different expectations and therefore noise annoyance in those two categories while scientific evidence is missing. It should be tested on empirically derived data. Surveys from two studies in the state of Tyrol in urban and rural areas were retrospectively matched with spatial data to analyze the potential different influences on noise effects. Using non-parametric tests, the correlation between land-use category on self-reported noise sensitivity and noise annoyance was investigated. Exposure–response for the two analyzed land-use categories showed no significant impact on noise sensitivity and exposure–response relationships for the three traffic noise sources. Including only noise annoyance, there is not sufficient evidence to define different noise policies for those two land-use categories.

Clinical drawings are integral part of image-guided adaptive brachytherapy (IGABT) of cervical cancer. It was used in EMBRACE study protocol as a useful tool. In our study clinical drawings from EMBRACE study were modified to include scales in all the dimensions for more accurate representation of various tumor related volumes. The aim of the present study was to understand patterns of tumor regression and relationship between gross tumor at diagnosis (GTVD) and high-risk clinical target volume (CTV-T )/intermediate-risk clinical target volume (CTV-T ) in brachytherapy (BRT), using modified clinical drawings. 42 cervical cancer patients, staged as FIGO IIB-IIIB according to EMBRACE study, were enrolled. Advanced schematic 3D mapping diagram (3D-MD) in axial, coronal, and sagittal orientations, with a measurement scale (grid with 10 mm distance) for precise assessment and documentation was applied (through MRI at diagnosis and during brachytherapy). Dimensions, including height, width, and thickness as well as volumes (GTVD, CTV-T and CTV-T ) were compared both qualitatively and quantitatively. We found qualitative and quantitative correlation of the dimensions of final CTV-T with initial GTVD. Meticulous mapping of tumor volumes can provide useful insights to CTV-T volume during brachytherapy.

Intra-fractional organs at risk (OARs) deformations can lead to dose variation during image-guided adaptive brachytherapy (IGABT). The aim of this study was to modify the final accepted brachytherapy treatment plan to dosimetrically compensate for these intra-fractional organs-applicators position variations and, at the same time, fulfilling the dosimetric criteria. Thirty patients with locally advanced cervical cancer, after external beam radiotherapy (EBRT) of 45-50 Gy over five to six weeks with concomitant weekly chemotherapy, and qualified for intracavitary high-dose-rate (HDR) brachytherapy with tandem-ovoid applicators were selected for this study. Second computed tomography scan was done for each patient after finishing brachytherapy treatment with applicators in situ. Artificial neural networks (ANNs) based models were used to predict intra-fractional OARs dose-volume histogram parameters variations and propose a new final plan. A model was developed to estimate the intra-fractional organs dose variations during gynaecological intracavitary brachytherapy. Also, ANNs were used to modify the final brachytherapy treatment plan to compensate dosimetrically for changes in 'organs-applicators', while maintaining target dose at the original level. There are semi-automatic and fast responding models that can be used in the routine clinical workflow to reduce individually IGABT uncertainties. These models can be more validated by more patients' plans to be able to serve as a clinical tool.

[INLINE:1] Author: Jamema Swamidas, Department of Medical Physcis, ACTREC, Tata Memorial Centre, Mumbai, India Title: Dosimetric studies in Image-Guided Adaptive Brachytherapy in Gynecological Cancers: A journey to successful implementation Pages: 203 Chief Guide: Prof. D.D. Deshpande, Department of Medical Physics, Tata Memorial Hospital, Mumbai, India Date of award: [...]fifth chapter summarizes the important findings of this thesis and also discusses the future direction of research. Magnetic resonance image guided adaptive brachytherapy in locally advanced cervical cancer: an experience from a tertiary cancer center in a low and middle income countries setting. Income generated by women treated with magnetic resonance imaging-based brachytherapy: A simulation study evaluating the macroeconomic benefits of implementing a high-end technology in a public sector healthcare setting.

To analyze the impact of heterogeneity-corrected dose calculation on dosimetric quality parameters in gynecological and breast brachytherapy using Acuros, a grid-based Boltzmann equation solver (GBBS), and to evaluate the shielding effects of different cervix brachytherapy applicators. Calculations with TG-43 and Acuros were based on computed tomography (CT) retrospectively, for 10 cases of accelerated partial breast irradiation and 9 cervix cancer cases treated with tandem-ring applicators. Phantom CT-scans of different applicators (plastic and titanium) were acquired. For breast cases the V20Gyαβ3 to lung, the D0.1cm(3) , D1cm(3) , D2cm(3) to rib, the D0.1cm(3) , D1cm(3) , D10cm(3) to skin, and Dmax for all structures were reported. For cervix cases, the D0.1cm(3) , D2cm(3) to bladder, rectum and sigmoid, and the D50, D90, D98, V100 for the CTVHR were reported. For the phantom study, surrogates for target and organ at risk were created for a similar dose volume histogram (DVH) analysis. Absorbed dose and equivalent dose to 2 Gy fractionation (EQD2) were used for comparison. Calculations with TG-43 overestimated the dose for all dosimetric indices investigated. For breast, a decrease of ~8% was found for D10cm(3) to the skin and 5% for D2cm(3) to rib, resulting in a difference ~ -1.5 Gy EQD2 for overall treatment. Smaller effects were found for cervix cases with the plastic applicator, with up to -2% (-0.2 Gy EQD2) per fraction for organs at risk and -0.5% (-0.3 Gy EQD2) per fraction for CTVHR. The shielding effect of the titanium applicator resulted in a decrease of 2% for D2cm(3) to the organ at risk versus 0.7% for plastic. Lower doses were reported when calculating with Acuros compared to TG-43. Differences in dose parameters were larger in breast cases. A lower impact on clinical dose parameters was found for the cervix cases. Applicator material causes systematic shielding effects that can be taken into account.

To analyze the optimum organ filling point for organs at risk (OARs) dose in cervical cancer high-dose-rate (HDR) brachytherapy. In a retrospective study, 32 locally advanced cervical cancer patients (97 insertions) who were treated with 3D conformal external beam radiation therapy (EBRT) and concurrent chemotherapy during 2010-2013 were included. Rotterdam HDR tandem-ovoid applicators were used and computed tomography (CT) scanning was performed after each insertion. The OARs delineation and GEC-ESTRO-based clinical target volumes (CTVs) contouring was followed by 3D forward planning. Then, dose volume histogram (DVH) parameters of organs were recorded and patients were classified based on their OARs volumes, as well as their inserted tandem length. The absorbed dose to point A ranged between 6.5-7.5 Gy. D0.1cm(3) and D2cm(3) of the bladder significantly increased with the bladder volume enlargement (p value < 0.05). By increasing the bladder volume up to about 140 cm(3), the rectum dose was also increased. For the cases with bladder volumes higher than 140 cm(3), the rectum dose decreased. For bladder volumes lower than 75 cm(3), the sigmoid dose decreased; however, for bladder volumes higher than 75 cm(3), the sigmoid dose increased. The D2cm(3) of the bladder and rectum were higher for longer tandems than for shorter ones, respectively. The divergence of the obtained results for different tandem lengths became wider by the extension of the bladder volume. The rectum and sigmoid volume had a direct impact on increasing their D0.1cm(3) and D2cm(3) , as well as decreasing their D10, D30, and D50. There is a relationship between the volumes of OARs and their received doses. Selecting a bladder with a volume of about 70 cm(3) or less proved to be better with regards to the dose to the bladder, rectum, and sigmoid.

The concept of the use of MRI for image-guided adaptive brachytherapy (IGABT) in locally advanced cervical cancer was introduced 20 years ago. Here, we report on EMBRACE-I, which aimed to evaluate local tumour control and morbidity after chemoradiotherapy and MRI-based IGABT. EMBRACE-I was a prospective, observational, multicentre cohort study. Data from patients from 24 centres in Europe, Asia, and North America were prospectively collected. The inclusion criteria were patients older than 18 years, with biopsy-proven squamous cell carcinoma, adenocarcinoma, or adenosquamous carcinoma of the uterine cervix, The International Federation of Gynecology and Obstetrics (FIGO) stage IB–IVA disease or FIGO stage IVB disease restricted to paraaortic lymph metastasis below the L1–L2 interspace, suitable for curative treatment. Treatment consisted of chemoradiotherapy (weekly intravenous cisplatin 40 mg/m2, 5–6 cycles, 1 day per cycle, plus 45–50 Gy external-beam radiotherapy delivered in 1·8–2 Gy fractions) followed by MRI-based IGABT. The MRI-based IGABT target volume definition and dose reporting was according to Groupe Européen de Curiethérapie European Society for Radiation Oncology recommendations. IGABT dose prescription was open according to institutional practice. Local control and late morbidity were selected as primary endpoints in all patients available for analysis. The study was registered with ClinicalTrials.gov, NCT00920920. Patient accrual began on July 30, 2008, and closed on Dec 29, 2015. A total of 1416 patients were registered in the database. After exclusion for not meeting patient selection criteria before treatment, being registered but not entered in the database, meeting the exclusion criteria, and being falsely excluded, data from 1341 patients were available for analysis of disease and data from 1251 patients were available for assessment of morbidity outcome. MRI-based IGABT including dose optimisation was done in 1317 (98·2%) of 1341 patients. Median high-risk clinical target volume was 28 cm3 (IQR 20–40) and median minimal dose to 90% of the clinical target volume (D90%) was 90 Gy (IQR 85–94) equi-effective dose in 2 Gy per fraction. At a median follow-up of 51 months (IQR 20–64), actuarial overall 5-year local control was 92% (95% CI 90–93). Actuarial cumulative 5-year incidence of grade 3–5 morbidity was 6·8% (95% CI 5·4–8·6) for genitourinary events, 8·5% (6·9–10·6) for gastrointestinal events, 5·7% (4·3–7·6) for vaginal events, and 3·2% (2·2–4·5) for fistulae. Chemoradiotherapy and MRI-based IGABT result in effective and stable long-term local control across all stages of locally advanced cervical cancer, with a limited severe morbidity per organ. These results represent a positive breakthrough in the treatment of locally advanced cervical cancer, which might be used as a benchmark for clinical practice and all future studies. Medical University of Vienna, Aarhus University Hospital, Elekta AB, and Varian Medical Systems.