Purpose: To quantify daily residual deviations from the planned geometry after image-guided prostate radiotherapy with endorectal balloon and to evaluate their effect on the delivered dose distribution.Methods: Daily kV-CBCT imaging was used for online setup-correction in six degrees of freedom (6-dof) for 24 patients receiving definitive (12 RT def patients) or postoperative (12 RT postop patients) radiotherapy with endorectal balloon (overall 739 CBCTs). Residual deviations were evaluated using several spatial and dosimetric variables, including: (a) posterior Hausdorff distance HD post (=maximum distance between planned and daily CTV contour), (b) point P worst with largest HD post over all fractions, (c) equivalent uniform dose using a cell survival model (EUD SF ) and the generalized EUD concept (gEUD a with parameter a = −7 and a = −20). EUD values were determined for planned (EUD plan SF ), daily (EUD ind SF ), and delivered dose distributions (EUD accum SF ) for plans with 6 mm (=clinical plans) and 2 mm CTV-to-PTV margin. Time series analyses of interfractional spatial and dosimetric deviations were conducted.Results: Large HD post values ≥ 12.5 mm (≥15 mm) were observed in 20/739 (5/739) fractions distributed across 7 (3) patients. Points P worst were predominantly located at the posterior CTV boundary in the seminal vesicle region (16/24 patients, 6/7 patients with HD post ≥ 12.5 mm). Time series analyses revealed a stationary white noise characteristic of HD post and relative dose at P worst . The EUD SF difference between planned and accumulated dose distributions was < 5.4% for all 6-mm plans. Evaluating 2-mm plans, EUD SF deteriorated by < 10% (<5%) in 75% (58.5%) of the patients. EUD accum SF was well described by the median value of the EUD ind SF distribution. PTV margin calculation at P worst yielded 8.8 mm.Conclusions: Accumulated dose distributions in prostate radiotherapy with endorectal balloon are forgiving of considerable residual distortions after 6-dof patient setup if they are observed in a minority of fractions and the median value of EUD ind SF

In an attempt to address the growing need for greener shipping, the potential of cold ironing technology, has been considered as one of the most effective methods to control the atmospheric emissions generated by marine industry. The present study focuses on the reduction of emissions occurred in anchorage areas of one of the busiest ports in Europe. For this purpose, an innovative design was produced by combining the method of cold ironing and the use of renewable energy sources such as wind farms, located close to the anchorage areas of Rotterdam Port. Electrical power produced by the windfarms will be stored in an offshore platform, distributed in a subsea station located outside the anchorage area and then to the vessels with the use of four calm buoys.

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