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An experimental study of the eta' -> pi(0)pi(0)eta -> 6 gamma decay has been conducted with the best up-to-date statistical accuracy, by measuring. 0 mesons produced in the gamma p -> eta'p reaction with the A2 tagged-photon facility at the Mainz Microtron, MAMI. The results obtained for the standard parametrization of the eta' -> pi(0)pi(0)eta matrix element are consistent with the most recent results for eta' -> pi pi eta decays, but have smaller uncertainties. The available statistics and experimental resolution allowed, for the first time, an observation of a structure below the pi(+)pi(-) thorn p-mass threshold, the magnitude and sign of which, checked within the framework of the nonrelativistic effective-field theory, demonstrated good agreement with the cusp that was predicted based on the pi pi scattering length combination, a(0)-a(2), extracted from K -> 3 pi decays.

The Dalitz decay π0 → e+e−γ has been measured in the γp → π0p reaction with the A2 tagged-photon\ud facility at the Mainz Microtron, MAMI. The value obtained for the slope parameter of the π0 electromagnetic\ud transition form factor, aπ = 0.030 ± 0.010tot, is in agreement with existing measurements of this decay and with\ud recent theoretical calculations. The uncertainty obtained in the value of aπ is lower than in previous results based\ud on the π0 → e+e−γ decay.

Existing scenarios of biodiversity and ecosystem services (BES) have important limitations and gaps that constrain their usefulness for the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES). Specifically, they fail to incorporate policy objectives related to nature conservation and social-ecological feedbacks, they do not address the linkages between biodiversity and ecosystem services, and they are typically relevant at only a particular spatial scale. In addition, nature and its benefits are treated as the consequence of human decisions, but are not at the centre of the analysis. To address these issues, the IPBES Scenarios and Models Expert Group initiated the development of a set of Multiscale Scenarios for Nature Futures based on positive visions for human relationships with nature.The first step of this process was a visioning workshop with stakeholders and experts on 4-8 September 2017 in Auckland, New Zealand. A total of 73 participants from inter-governmental organisations, national government organisations, non-governmental organisations, academia and the private sector, from 31 countries, and with a range of sectoral expertise on biodiversity topics, from urban development to agriculture to fisheries, worked together in a visioning exercise. This report documents the results from this visioning workshop to inform further stakeholder consultation and the development of the associated multiscale scenarios by modelers and experts. This creative visioning exercise was carried out in four steps based on a suite of participatory methods that were used to develop visions of alternative futures. First the participants identified important themes to develop the visions. Next, thematic groups identified the main trends for BES in each theme and a set of “Seeds” of emerging initiatives leading to positive futures for our relationship with nature. Implications of what would happen across a range of sectors were identified for each seed. Then a pathway analysis of how the current regime in each theme may be transformed into the future desirable regime was carriedout. Narratives were then built for the visions emerging from each group. Finally, commonalities of visions across the groups were identified, and the regional relevance of each vision for different parts of the world was assessed.

The reactions γp → ηp and γp → η0\ud p are measured from their thresholds up to the center-of-mass\ud energy W ¼ 1.96 GeV with the tagged-photon facilities at the Mainz Microtron, MAMI. Differential cross\ud sections are obtained with unprecedented statistical accuracy, providing fine energy binning and full\ud production-angle coverage. A strong cusp is observed in the total cross section for η photoproduction at the\ud energies in the vicinity of the η0 threshold, W ¼ 1896 MeV (Eγ ¼ 1447 MeV). Within the framework of a\ud revised ηMAID isobar model, the cusp, in connection with a steep rise of the η0 total cross section from its\ud threshold, can only be explained by a strong coupling of the poorly known Nð1895Þ1=2− state to both ηp\ud and η0\ud p. Including the new high-accuracy results in the ηMAID fit to available η and η0 photoproduction\ud data allows the determination of the Nð1895Þ1=2− properties.

A system for real time navigation of a nonholonomic car-like robot in a dynamic environment consists of two layers is described: a Sugeno-type fuzzy motion planner; and a modified proportional navigation based fuzzy controller. The system philosophy is inspired by human routing when moving between obstacles based on visual information including right and left views to identify the next step to the goal. A Sugeno-type fuzzy motion planner of four inputs one output is introduced to give a clear direction to the robot controller. The second stage is a modified proportional navigation based fuzzy controller based on the proportional navigation guidance law and able to optimize the robot's behavior in real time, i.e. to avoid stationary and moving obstacles in its local environment obeying kinematics constraints. The system has an intelligent combination of two behaviors to cope with obstacle avoidance as well as approaching a target using a proportional navigation path. The system was simulated and tested on different environments with various obstacle distributions. The simulation reveals that the system gives good results for various simple environments.

Without abstract.