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1. Ecoacoustics is increasingly being used to monitor species populations and to estimate biodiversity in marine ecosystems, but the underwater soundscapes of freshwater environments remain largely unexplored in this respect. Few studies exist concerning the acoustic diversity of ponds, but because aquatic plants and many arthropods such as Coleoptera and Hemiptera are known to produce sound, there is potential to use ecoacoustic techniques to monitor changes in biodiversity and conservation value. This pilot study compares the underwater soundscapes of recently restoredopen-canopy ponds and unmanaged highly terrestrialized ponds situated in an arable agricultural landscape of North Norfolk, UK, in order to assess the benefits of farmland pond restoration.3. Daytime sound recordings were made for 10 min in each pond and analysed primarily for arthropod stridulations. In addition, six commonly used acoustic indices were calculated to assess the soundscape biodiversity between the unmanaged and the restored ponds. The stridulations of three diving beetle

Rat soleus muscles were partially denervated by removal of the L5 ventral ramus at either 4 - 6 days or 17 - 19 days. Local application of leupeptin, a potent inhibitor of the calcium activated neutral protease to these operated muscles, resulted in a significantly greater maximal tetanic tension and motor unit size, when compared to untreated partially denervated muscles. This was achieved in the 4 - 6 day operated animals by an increased number of terminals and in the 17 - 19 day old animals by increased number of axonal sprouts that maintain contact with muscle fibres. In both groups of operated animals in the leupeptin treated muscles large numbers of motor units were able to maintain or achieve an expanded territory, whilst the size of the largest motor unit did not appear to be increased. It is proposed that leupeptin exerts its effect by inhibiting the degradative action of the neuronal calcium activated neutral protease on the axonal cytoskeleton. Such inhibition may act to prevent or decrease the degradation of cytoskeletal structures in the nerve terminal, and so provide protection for weak terminals at a synapse and growth cones of sprouting axons following partial denervation.

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