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An improved analytical framework and typology of fishers are provided to improve understanding of the diverse livelihood functions of inland fishing in development policy making. Inland fisheries make an important but often neglected contribution to rural livelihoods in developing countries. A holistic and widely applicable analysis of the possible livelihood functions of such fisheries is presented, focusing on fishing as one activity within diverse livelihoods. Four different livelihood strategies are identified, involving fishing as: (i) a primary livelihood of last resort, (ii) part of a diversified semi-subsistence livelihood, (iii) a specialist occupation and (iv) part of a diversified accumulation strategy. The policy implications of these strategies are found to be differentiated and poorly represented in practice by socio-economic analysis that either undfervalues fisheries or treats them solely as livelihoods of last resort and by traditional approaches to fisheries management centred on stock conservation. The need for a more diverse and flexible range of measures, tailored to local priorities and conditions and ensuring that poor people can access the benefits of inland fisheries whilst achieving conservation objectives, is identified.

SummaryPhagocytosis by cells of the innate immune system, such as macrophages, and the subsequent successful maturation of the phagosome, is key for the clearance of pathogens. The fungal pathogen Cryptococcus neoformans is known to overcome killing by host phagocytes and both replicate within these cells and also escape via a non-lytic process termed vomocytosis. Here we demonstrate that, during intracellular growth, cryptococci modify phagolysosome maturation. Live cryptococci, but not heat-killed pathogens or inert targets, induce the premature removal of the early phagosome markers Rab5 and Rab11. In addition, significant acidification of the phagosome, calcium flux and protease activity is hindered, thus rendering the phagosome permissive for cryptococcal proliferation. Interestingly, several attenuated cryptococcal mutants retain this ability to subvert phagosomal maturation, suggesting that hitherto unidentified pathogen mechanisms regulate this process.

Cryptococcus gattii is an emerging intracellular pathogen and the cause of the largest primary outbreak of a life-threatening fungal disease in a healthy population. Outbreak strains share a unique mitochondrial gene expression profile and an increased ability to tubularise their mitochondria within host macrophages. However, the underlying mechanism that causes this lineage of C. gattii to be virulent in immunocompetent individuals remains unexplained. Here we show that a subpopulation of intracellular C. gattii adopts a tubular mitochondrial morphology in response to host reactive oxygen species. These fungal cells then facilitate the rapid growth of neighbouring C. gattii cells with non-tubular mitochondria, allowing for effective establishment of the pathogen within a macrophage intracellular niche. Thus, host reactive oxygen species, an essential component of the innate immune response, act as major signalling molecules to trigger a “division of labour” in the intracellular fungal population, leading to increased pathogenesis within this outbreak lineage.

ABSTRACTGroup BStreptococcus(GBS) is a leading cause of neonatal meningitis and septicemia. The ability of this organism to survive inside phagocytic cells is poorly understood but thought to be an important step for the establishment of disease in the host. Here, we demonstrate that GBS shows prolonged survival within J774 macrophages and that the capacity to survive is not significantly changed across a diverse range of strains representing different serotypes, multilocus sequence types (MLST), and sites of clinical isolation. Using staining for the lysosome-associated membrane protein (LAMP) and by pharmacological inhibition of phagosome acidification, we demonstrate that streptococci reside in a phagosome and that acidification of the phagosome is required for GBS to survive intracellularly. Moreover, we show that the GBS two-component system CovS/CovR, which is the major acid response regulator in this organism, is required for survival inside the phagosome.

In this paper we examine sources of technical efficiency for rice farming in Bangladesh. The motivation for the analysis is the need to close the rice yield gap to enable food security. We employ the DEA double bootstrap of Simar and Wilson (2006) to estimate and explain technical efficiency. This technique overcomes severe limitations inherent in using the two-stage DEA approach commonly employed in the efficiency literature. From a policy perspective our results show that potential efficiency gains to reduce the yield gap are greater than previously found. Statistically positive influences on technical efficiency are education, extension and credit, with age being a negative influence.

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