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Emerging pollutants such as pharmaceuticals are continuously released to aquatic environments posing a rising threat to marine ecosystems. Yet, monitoring routines and ecotoxicity data on biota worldwide for these substances are lacking. Non-steroidal anti-inflammatory drugs are among the most prescribed and found pharmaceuticals in aquatic environments. The toxicity effects of environmentally relevant concentrations of ibuprofen on primary productivity, oxidative stress and lipid metabolism of the diatom Phaeodactylum tricornutum were assessed. Diatom cultures were exposed to 0, 0.8, 3, 40, 100 and 300 μg L-1 ibuprofen concentrations, usually found in the vicinity of wastewater treatment plants and coastal environments. see more Higher concentrations (100 and 300 μg L-1) had a negative impact in P. triconutum growth, inhibiting the chloroplastic energy transduction in the electron transport chain resulting in lower energy reaching the PS I (r2 = -0.55, p less then 0.05). In contrast, the mitochondrial electron transport and available energy increased (r2 = 0.68 and r2 = 0.85, p less then 0.05 respectively), mostly due to enhancements in lipid and protein contents as opposed to reduction of carbohydrates. A general up-regulation of the antioxidant enzymes could contributed to alleviate oxidative stress resulting in the decrease of lipid peroxidation products (r2 = 0.77, p less then 0.05). Canonical analysis of principal components was performed and successfully discriminated exposure groups, with optical data excelling in classifying samples to different ibuprofen concentrations, being potentially used as environmental indicators. Finally, the identified mild to severe effects of ibuprofen on diatoms are likely to be exacerbated by the sustained use of this drug worldwide, underpinning the urgency of evaluating the impacts of this pharmaceutical on coastal and marine trophic webs.Environmental impacts from wave energy generators on the local mobile mega- and macrofauna community have been investigated in the Lysekil project by Uppsala University. Offshore renewable energy installations provide hard, artificial substrates, and as such, they could act as artificial reefs. Foundations with manufactured holes served as complex habitats and foundations without served as non-complex. In this long-term study, SCUBA surveys of mobile fauna in the years 2007, 2008 and 2016-2019 were analyzed. The results show a distinct reef effect on the foundations with significant greater species richness, total number of individuals, greater values of the Shannon-Wiener biodiversity index, and greater abundance of specific reef fauna. Complex foundations accommodated a greater abundance of brown crabs than non-complex foundations, other taxa did not show differences between the two foundation types. A successional increase of species richness, numbers of individuals and Shannon-Wiener biodiversity could be revealed from the first to the second survey period. Inter-annual variation was visible throughout all taxa and years.

In-vitro radiobiological studies are essential for modelling the relative biological effectiveness (RBE) in proton therapy. The purpose of this study was to experimentally determine the RBE values in proton beams along the beam path for human prostate carcinoma cells (Du-145). RBE-dose and RBE-LET

(dose-averaged linear energy transfer) dependencies were investigated and three phenomenological RBE models, i.e. McNamara, Rørvik and Wilkens were benchmarked for this cell line.

Cells were placed at multiple positions along the beam path, employing an in-house developed solid phantom. The experimental setup reflected the clinical prostate treatment scenario in terms of field size, depth, and required proton energies (127.2-180.1MeV) and the physical doses from 0.5 to 6Gy were delivered. The reference irradiation was performed with 200kV X-ray beams. Respective (α/β) values were determined using the linear quadratic model and LET

was derived from the treatment planning system at the exact location of cells.E values with LETd parameter suggests that proton LET must be taken into consideration for this low (α/β) tissue.

The entrance beam fluence of therapeutic proton scanning beams can be monitored using a gantry-attachable plastic scintillating plate (GAPSP). This study evaluated the clinical application of the GAPSP using a method that measures intensity modulated proton therapy (IMPT) beams for patient treatment.

IMPT beams for the treatment of nine patients, at sites that included the spine, head and neck, pelvis, and lung, were measured using the GAPSP, composed of an EJ-212 plastic scintillator and a CMOS camera. All energy layers distinguished by the GAPSP were accumulated to determine the dose distribution of the treatment field. The evaluated fields were compared with reference dose maps verified by quality assurance.

Comparison of dose distributions of evaluation treatment fields with reference dose distributions showed that the 3%/1 mm average gamma passing rate was 96.4%, independent of the treatment site, energy range and field size. When dose distributions were evaluated using the same criteria for each energy layer, the average gamma passing rate was 91.7%.

The GAPSP is a suitable, low-cost method for monitoring pencil beam scanning proton therapy, especially for non-spot scanning or additional collimation. The GAPSP can also estimate the treatment beam by the energy layer, a feature not common to other proton dosimetry tools.

The GAPSP is a suitable, low-cost method for monitoring pencil beam scanning proton therapy, especially for non-spot scanning or additional collimation. The GAPSP can also estimate the treatment beam by the energy layer, a feature not common to other proton dosimetry tools.

To examine whether it is essential to apply correction factors for ion recombination (k

) to percentage depth dose (PDD) measurements and to the volume-averaging effect (k

) to ensure accurate absolute dose calibration for flattening filter-free (FFF) beams for the most commonly used ionization chambers.

We surveyed medical physicists worldwide (n=159) to identify the five most common ionization chamber combinations used for absolute and relative reference dosimetry of FFF beams. We then assessed the overall absolute dose calibration error for FFF beams of the Artiste Siemens and TrueBeam Varian linear accelerators resulting from failing to apply correction factors k

in the PDD(10) and the volume-averaging effect (k

) to such chamber combinations.

All the chamber combinations examined-the Farmer PTW 30013 ionization chamber used for absolute dosimetry, and the PTW 31010, PTW 30013, IBA CC04, IBA CC13, and PTW 31021 ionization chambers used for PDD curves measurements-showed non-negligible errors (≥0.