25,947 research outputs found
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Joined-up food policy? The trials of governance, public policy and the food system
To address the policy malfunctions of the recent past and present, UK food policy needs to link policy areas that in the past have been dealt with in a disparate manner, and to draw on a new ecological public health approach. This will need a shift within the dominant trade liberalizationânational economic competitiveness paradigm that currently informs UK food policy, and the international levels of the EU and the WTO trade rules, and grants the large corporate players in the food system a favoured place at the policyâmaking tables. The contradictions of the food system have wrought crises that have engendered widespread institutional change at all levels of governance. Recent institutional reforms to UK food policy, such as the FSA and DEFRA, reflect a bounded approach to policy integration. Initiatives seeking a more integrated approach to food policy problems, such as the Social Exclusion Unitâs access to shops report, and the Policy Commission on the Future of Food and Farming, can end up confined to a particular policy sector framed by particular interestsâa process of âpolicy confinementâ. However, the UK can learn from the experience of Norway and Finland who have found their own routes to a more joinedâup approach to public health and a sustainable food supply by, for example, introducing a national food policy council to provide integrated policy advice. Also, at the local and community levels in the UK, policy alternatives are being advanced in an ad hoc fashion by local food initiatives. More structuralâlevel interventions at the regional and local governance levels are also needed to address the social dimensions of a sustainable food suppl
Quantum critical behaviour of the plateau-insulator transition in the quantum Hall regime
High-field magnetotransport experiments provide an excellent tool to
investigate the plateau-insulator phase transition in the integral quantum Hall
effect. Here we review recent low-temperature high-field magnetotransport
studies carried out on several InGaAs/InP heterostructures and an InGaAs/GaAs
quantum well. We find that the longitudinal resistivity near the
critical filling factor ~ 0.5 follows the universal scaling law
, where . The critical exponent equals ,
which indicates that the plateau-insulator transition falls in a non-Fermi
liquid universality class.Comment: 8 pages, accepted for publication in Proceedings of the Yamada
Conference LX on Research in High Magnetic Fields (August 16-19, 2006,
Sendai
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Role of government policy in nutrition-barriers to and opportunities for healthier eating
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Food security and food sustainability: reformulating the debate
The notion of food security has an important history as a key concept for 20th-century policymakers. Two overarching perspectives on food security are identified. One centred on raising production as the core answer to under-consumption and hunger. The other is an emerging perspective, more social and ecological, accepting the need to address a complex array of problems, not just production. The first is primarily agricultural-focused; the latter a food systems approach. From its inception in post-World War 2 international reconstruction, the UN and governments have given tackling hunger a high profile, via a changing package of policy measures. Within a few decades, the production-oriented approach or paradigm was being questioned by the emerging paradigm with its more complex, multi-focused notion of the challenges ahead. When oil and agricultural commodity prices spiked in 2007â8, the complex agenda was marginalised by a renewed international focus on primary production and the needs of low-income countries. Against this background, the paper explores the diversity of perspectives on what is meant by food security, concluding that the core 21st-century task is to create a sustainable food system. This requires a more coherent policy framework than currently exists, a goal thwarted by competing solutions vying for policy attention and policy failure thus far to integrate the complex range of evidence from social as well as environmental and economic sources into an integrated policy response
Cleaning the USNO-B Catalog through automatic detection of optical artifacts
The USNO-B Catalog contains spurious entries that are caused by diffraction
spikes and circular reflection halos around bright stars in the original
imaging data. These spurious entries appear in the Catalog as if they were real
stars; they are confusing for some scientific tasks. The spurious entries can
be identified by simple computer vision techniques because they produce
repeatable patterns on the sky. Some techniques employed here are variants of
the Hough transform, one of which is sensitive to (two-dimensional)
overdensities of faint stars in thin right-angle cross patterns centered on
bright (<13 \mag) stars, and one of which is sensitive to thin annular
overdensities centered on very bright (<7 \mag) stars. After enforcing
conservative statistical requirements on spurious-entry identifications, we
find that of the 1,042,618,261 entries in the USNO-B Catalog, 24,148,382 of
them (2.3 \percent) are identified as spurious by diffraction-spike criteria
and 196,133 (0.02 \percent) are identified as spurious by reflection-halo
criteria. The spurious entries are often detected in more than 2 bands and are
not overwhelmingly outliers in any photometric properties; they therefore
cannot be rejected easily on other grounds, i.e., without the use of computer
vision techniques. We demonstrate our method, and return to the community in
electronic form a table of spurious entries in the Catalog.Comment: published in A
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Avoiding Future Famines: Strengthening the Ecological Foundation of Food Security through Sustainable Food Systems. A UNEP Synthesis Report
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