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Abstract: A semi-automated system has been designed and installed for the routine production of highly concentrated solutions of rhenium-188 perrhenate in saline which incorporates extensive radiation protection for the laboratory staff. This new system represents a simple, rapid, and effective computer controlled method using inexpensive disposable components. The flipper-valve settings and the radioactivity measured by use of collimated gamma dose rate probes are continuously monitored. If necessary, 2–3 tungsten-188/rhenium-188 generators can be eluted in a tandem arrangement. Eluate volumes (1.3–2ml) of maximum specific radioactivity of 25GBq/ml were routinely prepared. [Copyright &y& Elsevier]

Despite their crucial biological relevance, the neural structures differentially activated by the detection of optic flow towards the observer remain to be elucidated. Here, we deploy functional magnetic resonance imaging with normal volunteers to locate the areas differentially activated when motion towards the observer is detected. Motion towards the observer, compared with motion away, showed significant activations (P<0.05, corrected for multiple comparisons), as assessed using statistical parametric mapping, in the lateral inferior occipital cortex bilaterally and in right lateral superior occipital cortex. The areas implicated do not extend into area V5 or subdivisions thereof.Our data suggest that the representations of motion towards the observer implicate perceptual and attentional mechanisms acting at early stages of visual processing in extrastriate cortex. From the standpoint of efficient biological engineering, it makes sense that such crucially important functions as object motion towards the observer would be computed in early visual processing areas. Further studies will be required to determine the extent to which the effects we observed in lateral occipital cortex reflect differential attention to different types of motion, as contrasted with the derivation of explicit representations of motion towards the observer. [Copyright &y& Elsevier]