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Wheat is a crop of global importance that supplies carbohydrates to more than half of the worlds’ population. We examined whether climate change-induced rainfall patterns, which are expected to produce less frequent but heavier rain events, will alter the productivity of wheat and agroecosystem functioning on three different soil types. Therefore, in a full-factorial experiment, Triticum aestivum L. was cultivated in 3-m2 lysimeter plots, each of which contained one of the following soil types: sandy calcaric phaeozem, gleyic phaeozem and calcic chernozem. Predicted rainfall patterns based on the calculations of a regionalised climate change model were compared with the current long-term rainfall patterns, and each treatment combination was replicated three times. Future rainfall patterns significantly reduced wheat yield, leaf area index, and plant height at the earlier growth stages; it equally decreased the arbuscular mycorrhizal fungi colonisation of roots and increased the stable carbon isotope signature (δ13C) of wheat leaves. Sandy soils with inherently lower mineralization potential negatively affected wheat growth, harvest index, and yield but stimulated early season root production. The interaction between rainfall and soil type was significant for the harvest index and early wheat development. Our results suggest that changes in rainfall intensity and frequency can significantly affect the functioning of wheat agroecosystems. Wheat production under future rainfall conditions will likely become more challenging as further concurrent climate change factors become prevalent.

Assistance of robotic systems in the operating room promises higher accuracy and, hence, demanding surgical interventions become realisable (e.g. the direct cochlear access). Additionally, an intuitive user interface is crucial for the use of robots in surgery. Torque sensors in the joints can be employed for intuitive interaction concepts. Regarding the accuracy, they lead to a lower structural stiffness and, thus, to an additional error source. The aim of this contribution is to examine, if an accuracy needed for demanding interventions can be achieved by such a system or not. Feasible accuracy results of the robot-assisted process depend on each work-flow step. This work focuses on the determination of the tool coordinate frame. A method for drill axis definition is implemented and analysed. Furthermore, a concept of admittance feed control is developed. This allows the user to control feeding along the planned path by applying a force to the robots structure. The accuracy is researched by drilling experiments with a PMMA phantom and artificial bone blocks. The described drill axis estimation process results in a high angular repeatability ( $$0.026^\circ \,\pm \,16^\circ $$ ). In the first set of drilling results, an accuracy of $$(50\,\pm \,20\,\upmu {\mathrm {m}})$$ at entrance and $$(170\,\pm \,50\,\upmu {\mathrm {m}})$$ at target point excluding imaging was achieved. With admittance feed control an accuracy of $$(250\,\pm \,90\,\upmu {\mathrm {m}})$$ at target point was realised. In a third set twelve holes were drilled in artificial temporal bone phantoms including imaging. In this set-up an error of $$(20\,\pm \,15\,\upmu {\mathrm {m}})$$ and $$(165\,\pm \,80\,\upmu {\mathrm {m}})$$ was achieved. The results of conducted experiments show that accuracy requirements for demanding procedures such as the direct cochlear access can be fulfilled with compliant systems. Furthermore, it was shown that with the presented admittance feed control an accuracy of less then $$1\,\mathrm {mm}$$ is achievable.

Background and purpose Detailed knowledge of quality of life (QoL) after permanent I-125 brachytherapy may aid in counselling patients with early-stage prostate cancer. Materials and methods Seventy-four consecutive patients with low-risk prostate cancer were asked to complete the EORTC QLQ-C30 questionnaire with the prostate-specific PR25 module before implant, four weeks and one year after implant (response rates 97%, 88% and 89%, respectively). Implant characteristics were correlated with QoL scores. Results Global QoL was stable from pre-treatment to one year after implant and similar to age-adjusted scores of healthy controls. Significant changes versus baseline in QLQ-C30 domains were worsened social function at four weeks, increased constipation at four weeks and at one year and improved emotional function at one year. PR25 urinary symptoms were significantly increased at four weeks and, despite some improvement, at one year; bowel symptoms were slightly increased. Both types of symptoms were most strongly related with pre-treatment symptom scores. Prostate-V150 was the only implant parameter significantly associated with both urinary and bowel symptoms at four weeks and one year. Conclusions Limiting the high-dose subvolume in the prostate may be beneficial to reduce urinary and bowel symptoms but the major determinant of symptoms after I-125 implant is the baseline symptom level.