Microscale patchiness of virioplankton

The microscale spatial distributions of viruses were investigated in three contrasting environments including oligotrophic open ocean, eutrophic coastal and estuarine habitats. The abundances of two discrete populations of both viruses and heterotrophic bacteria were measured at spatial resolutions of between 1 and 5 cm using purpose-designed microscale sampling equipment and flow cytometric sample analysis. Within open water samples, virus distributions were characterized by non-normal distributions and by 'hotspots' in abundance where concentrations varied by up to 17-fold. In contrast to patterns generally observed at larger spatiotemporal scales, there was no correlation between bacterial and viral abundance or correspondence between bacteria and virus hotspots within these samples. Consequently, strong hotspots and gradients in the virus:bacteria ratio (VBR) were also apparent within samples. Within vertical profiles taken from above the sediment-water interface within a temperate mangrove estuary, distributions of planktonic viruses were characterized by gradients in abundance, with highest concentrations observed within the 1-2 cm immediately above the sediment surface, and virus distributions were correlated to bacterial abundance (P<0.01). The patterns observed in these contrasting habitats indicate that microscale patchiness of virus abundance may be a common feature of the marine environment. This form of heterogeneity may have important implications for virus-host dynamics and subsequently influence microbial trophodynamics and nutrient cycling in the ocean

Research networks: enhancing change in Australian primary health care

As primary health care disciplines evolve and strengthen both in Australia and internationally, primary care practitioners need to develop their research capacity at all levels. This paper discusses the changing face of primary health care and the emergence of primary care research networks as agents for research skills capacity building. Much can be learnt from international experiences, such as those in the United Kingdom, in terms of network models and approaches that have demonstrated successful outcomes including increased grant applications, research higher degree completions and publications. However, these outcomes are at least partly dependent on different contexts of health care services, and higher levels of funding. Enhancing change in Australian primary care research must take into account the Australian context, available resources, and be prepared to innovate in response to widely varying local and regional needs. The paper will discuss options and challenges for future directions in Australian research networks

Geostatistical characterisation of centimetre-scale spatial structure of in vivo fluorescence

Oldenort/Luhe, German