Comparison of linear optics quantum-computation control-sign gates with ancilla inefficiency and an improvement to functionality under these conditions

We compare three proposals for nondeterministic control-sign gates implemented using linear optics and conditional measurements with nonideal ancilla mode production and detection. The simplified Knill-Laflamme-Milburn gate [Ralph , Phys. Rev. A 65, 012314 (2001)] appears to be the most resilient under these conditions. We also find that the operation of this gate can be improved by adjusting the beam splitter ratios to compensate to some extent for the effects of the imperfect ancilla.

Effects of harvesting callianassid (ghost) shrimps on subtropical benthic communities

The effects of harvesting of callianassid shrimp (Trypaea australiensis) on the abundance and composition of macrobenthic assemblages in unvegetated sediments of a subtropical coastal embayment in Queensland, Australia were examined using a combination of sampling and manipulative experiments. First, the abundance and composition of the benthic infauna in an area regularly used for the collection of shrimp for bait by recreational anglers was compared with multiple reference areas. Second, a BACI design, with multiple reference areas, was used to examine the short-term effects of harvesting on the benthic assemblages from an intensive commercialised fishing competition. Third, a large-scale, controlled manipulative experiment, where shrimp were harvested from 10,000 m(2) plots at intensities commensurate with those from recreational and commercial operators, was done to determine the impacts on different components of the infaunal assemblage. Only a few benthic taxa showed significant declines in abundance in response to the removal of ghost shrimp from the unvegetated sediments. There was evidence, however, of more subtle effects with changes in the degree of spatial variation (patchiness) of several taxa as a result of harvesting.. Groups such as capitellid polychaetes, gammarid amphipods and some bivalves were significantly more patchy in their distribution in areas subjected to harvesting than reference areas, at a scale of tens of metres. This scale corresponds to the patterns of movement and activity of recreational harvesters working in these areas. In contrast, patchiness in the abundance of ghost shrimp decreased significantly under harvesting at scales of hundreds of metres, in response to harvesters focussing their efforts on areas with greater numbers of burrow entrances, leading to a more even distribution of the animals. Controlled experimental harvesting caused declines in the abundance of soldier crabs (Mictyris longicarpus), polychaetes and amphipods and an increase in the spatial patchiness of polychaetes. Populations of ghost shrimp were, however, resilient to harvesting over extended periods of time. In conclusion, harvesting of ghost shrimp for bait by recreational and commercial fishers causes significant but localised impacts on a limited range of benthic fauna in unvegetated sediments, including changes in the degree of spatial patchiness in their distribution. (c) 2005 Elsevier B.V. All rights reserved.

Social capital society and peace: Reflections on conflict transformation in the Philippines

Civil society is recognised as comprising complex and multifaceted entities, resilient to and yet responsive to both the state apparatus and global market processes. Civil society in the Philippines, long regarded as one of the most vibrant, diverse and innovative in Asia, has emerged as a significant actor in the field of conflict resolution and peace-building. In thinking about the work of peace, this paper engages with the effectiveness of civil society in mobilising societal awareness for a ‘just and lasting peace’ in the southern Philippines. Shaped by development paradigms that privilege concepts such as social capital, the paper aims to interrogate how such concepts situated within the development–security nexus proposed by the Philippine government and funding agencies have influenced conflict-transformation initiatives in Mindanao, Philippines.