No abstract

An entomological radar was used to observe insect flight activity at a coastal locality in north-western Tasmania during the spring of 1973. Insects were regularly observed to take off at dusk, and local movements from nearby islands were detected on several occasions. Large-scale southward movements of insects across Bass Strait were also observed and were found to be associated with the warm anticyclonic airflows which occur ahead of a cold front. Light-trap catches indicated that the insects were noctuid moths, with Persectania ewingii (Westw.), Heliothis punctiger

The distribution of shore crabs, Carcinus maenas (L.), within the intertidal and shallow subtidal zones of a rocky shore in the Menai Strait, North Wales, was recorded regularly by diving throughout the tidal cycle. Samples were also obtained by searching the shore during low tide and by collecting crabs in baited pots. It was found that the smaller individuals (<35 mm carapace width) in the population tend to remain within the intertidal throughout the tidal cycle whilst others, mainly the red-coloured adults, appear to remain permanently below low-water mark. The remainder of the population, predominantly green males larger than 35 mm carapace width, migrate upshore with the flood tide and downshore again with the ebb. The behaviour of C. maenas on the shore appears to be affected, at least in part, by a tidally rhythmic pattern of responsiveness to directional light which is seen in freshly collected crabs in the laboratory.

Shore crabs Carcinus rnaenas collected in winter normally exhibit circadan but not circatidal rhythmicity. When introduced into 20 % seawater (7 ppt), a circatidal rhythmic activity pattern is induced phased to the time of introduction. There is no apparent change in the phase of the extant circadian rhythm which, after treatment, acts to modulate the expression of the circatidal rhythm, the peaks of which are greatest during 'expected' night. These findings suggest that there are separate mechanisms for the control of circadian and circatidal rhythmicity in C. rnaenas. They permit a new appraisal of a key question in rhythm biology as to whether circatidal and circadian rhythmicity can be considered as expressions of the same physioloqcal mechanism.

Recent innovations in drug therapies have made it highly desirable to obtain sensitive biomarkers of disease progression that can be used to quantify the performance of candidate disease modifying drugs. In order to measure potential image-based biomarkers of disease progression in an experimental model of rheumatoid arthritis (RA), we present two different methods to automatically quantify changes in a bone in in-vivo serial magnetic resonance (MR) images from the model. Both methods are based on rigid and nonrigid image registration to perform the analysis. The first method uses segmentation propagation to delineate a bone from the serial MR images giving a global measure of temporal changes in bone volume. The second method uses rigid body registration to determine intensity change within a bone, and then maps these into a reference coordinate system using nonrigid registration. This gives a local measure of temporal changes in bone lesion volume. We detected significant temporal changes in local bone lesion volume in five out of eight identified candidate bone lesion regions, and significant difference in local bone lesion volume between male and female subjects in three out of eight candidate bone lesion regions. But the global bone volume was found to be fluctuating over time. Finally, we compare our findings with histology of the subjects and the manual segmentation of bone lesions.