BackgroundBlack sparrowhawks (Accipiter melanoleucus) recently colonised the Cape Peninsula, South Africa, where the species faces competition for their nest sites from Egyptian geese (Alopochen aegyptiaca) which frequently usurp black sparrowhawk nests. In this paper, we test the hypothesis that multiple nest building by black sparrowhawks is a strategy to cope with this competitor, based on a 14-year long term data set.ResultsTwo main results support the hypothesis: first, the numbers of intact nests per breeding season in black sparrowhawk territories increased as levels of geese interactions increased, specifically when usurpation occurred. Usurpation occurred significantly more often at nests later in the season, and may provide a further explanation for the advancement of the black sparrowhawk breeding season towards earlier breeding attempts which results in an overall extension of the breeding period (over 9 months) that has been found in our study population. Second, nest usurpation had a negative impact on black sparrowhawks’ reproductive performance at the ‘nest’ level, but not at the ‘territory’ level when multiple nests were available within the same breeding season, suggesting that this strategy was effective for dealing with this competitor. However, our results do not rule out long term negative consequences of these interactions, for example, reduced adult survival rates or reduced lifetime reproductive success, due to the higher energy demand required to build several nests each breeding season.ConclusionsOur results suggest that black sparrowhawks avoid direct conflict with this large and aggressive competitor and instead choose the passive strategy in allocating more resources to multiple nest building. Our research further highlights the importance of behavioural plasticity, which might be especially important for city-dwelling species in the face of global urbanisation.Electronic supplementary materialThe online version of this article (doi:10.1186/s12862-016-0671-7) contains supplementary material, which is available to authorized users.

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Purpose/Objective(s): Clinical evidence suggests that radiation dose received by the hippocampus during whole brain radiotherapy may play a role in radiation-induced neurocognitive decline. To prospectively evaluate the neurocognitive (NC) benefit of hippocampal sparing (PCI-HA), we have developed a phase III clinical trial (PREMER) to test hippocampal sparing during PCI. Materials/Methods: 118 patients undergoing PCI were randomized to receive PCI (nZ60) or PCI-HA (nZ58). The hippocampus was contoured, and hippocampal avoidance regions were created using a 5-mm volumetric expansion around the hippocampus. Linear accelerator ebased intensitymodulated radiotherapy and Volumetric Modulated Arc Therapy treatment plans were generated for a prescription dose of 25 Gy in 10 fractions. The main objective was NC function at 3 months assessed by Free and Cued Selective Reminding Test (FCSRT). The FCSRT is a well-validated and reliable assessment of memory, including encoding, retrieval, and retention of new information over time. Results: These treatment modalities spared the hippocampus, with a D100 of 8.4 AE 2.0 Gy and a maximum dose of 14.5 AE 3.3 Gy. There was a decline in free delayed recall in PCI vs PCI-HA arm at 3 months (21.7 vs 5.1%; p 0.01; OR 5 [IC 95% 1.36-18.87]) at 6 months (32.6 vs 7.3%; p 0.008; OR 6.1 [IC 95% 1.60-23.29]) and at 12 months (18.5 vs 3.8%; p 0.09; OR 5.7 [IC 95% 0.61-52.42])

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