5 research outputs found

    Thermal Evolution of the Proton Irradiated Structure in Tungsten–5 wt% Tantalum

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    We have monitored the thermal evolution of the proton irradiated structure of W–5 wt% Ta alloy by in-situ annealing in a transmission electron microscope at fusion reactor temperatures of 500–1300 °C. The interstitial-type a/2 dislocation loops emit self-interstitial atoms and glide to the free sample surface during the early stages of annealing. The resultant vacancy excess in the matrix originates vacancy-type a/2 dislocation loops that grow by loop and vacancy absorption in the temperature range of 600–900 °C. Voids form at 1000 °C, by either vacancy absorption or loop collapse, and grow progressively up to 1300 °C. Tantalum delays void formation by a vacancy-solute trapping mechanism

    Non-Human Predator Interactions with Wild Great Apes in Africa and the Use of Camera Traps to Study Their Dynamics

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    The slow life histories of great apes (hereafter ‘apes') combined with a growing inventory of predation incidents suggest that apes may be strongly affected by direct predation, as well as by predation risk. Predation risk may shape and increase behavioural flexibility by forcing individuals to adapt their behaviour to predator patterns. Forest leopards are an apex predator of primates in African rain forests and may represent a significant risk to ape populations. More field data are needed to further elucidate the behavioural modifications of apes in response to predation. We present research methods that combine the use of remote camera traps, capture-mark-recapture statistics and occupancy modelling to study predator-African ape relationships and potential antipredator behaviour through spatial variation in species co-occurrence patterns
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