Investigations on the Analysis and Design of Aperiodic Frequency Selective Surfaces for Space Applications

An investigation on the design of aperiodic FSS is presented. First, an accurate yet efficient method which allows the analysis of finite sized aperiodic FSS has been developed. Subsequently, an optimisation method is implemented which optimises all the FSS elements to obtain an FSS design with an aperiodic element layout. Preliminary designs of aperiodic FSS are presented and the numerical results are discussed.

True navigation in migrating gulls requires intact olfactory nerves

During migratory journeys, birds may become displaced from their normal migratory route. Experimental evidence has shown that adult birds can correct for such displacements and return to their goal. However, the nature of the cues used by migratory birds to perform long distance navigation is still debated. In this experiment we subjected adult lesser black-backed gulls migrating from their Finnish/Russian breeding grounds (from >60°N) to Africa (to < 5°N) to sensory manipulation, to determine the sensory systems required for navigation. We translocated birds westward (1080 km) or eastward (885 km) to simulate natural navigational challenges. When translocated westwards and outside their migratory corridor birds with olfactory nerve section kept a clear directional preference (southerly) but were unable to compensate for the displacement, while intact birds and gulls with the ophthalmic branch of the trigeminal nerve sectioned oriented towards their population-specific migratory corridor. Thus, air-borne olfactory information seems to be important for migrating gulls to navigate successfully in some circumstances.

Exploring communication between social workers, children and young people

A key issue for the social work profession concerns the nature, quality and content of communicative encounters with children and families. This article introduces some findings from a project funded by the Economic and Social Research Council (ESRC) that took place across the United Kingdom between 2013 and 2015, which explored how social workers communicate with children in their everyday practice. The Talking and Listening to Children (TLC) project had three phases: the first was ethnographic, involving observations of social workers in their workplace and during visits; the second used video-stimulated recall with a small number of children and their social workers; and the third developed online materials to support social workers. This paper discusses findings from the first phase. It highlights a diverse picture regarding the context and content of communicative processes; it is argued that attention to contextual issues is as important as focusing on individual practitioners’ behaviours and outlines a model for so doing.