“Waiting for Godot”- Restructuring on Small Family Farms

This paper examines the extent to which favourable off-farm labour market conditions coupled with growth in land values have contributed to the observed resilience of small scale family farms. We use data from Northern Ireland and employ farm household optimisation models to analyse household decision making processes that contribute to the observed inertia in farm structure. The analysis indicates that farm household behaviour is influenced not just by current farm income, but also expected capital asset returns. Increased wealth, associated with continuing land ownership, gives rise to the proposition that the link between off-farm incomes, increased land values and remaining in farming may be associated with farmers pursuing wealth maximizing objectives, whilst still maintaining a rural way of life. Alongside increased wealth through land ownership the farm household model quantifies the importance of off-farm income removing the pressure from farming income to fund all family consumption needs. This enables households to sustain low-income farming activities in order to pursue other objectives such as wealth management (including tax efficient transfer of wealth) and lifestyle. Consequently, the results indicate that the survival of small-scale family farms may be much less sensitive to agricultural support policies than has been commonly suggested. In an extension that explores the effects of the recent economic turbulence due to the ‘credit crunch’ we find that the households remain resilient even when subjected to a protracted period of reduced off-farm employment.Farm households, resilience, wealth accumulation, off-farm income, Consumer/Household Economics, Productivity Analysis, C61, Q12,

Spherical Formulation for Diagramatic Evaluations on a Manifold with Boundary

The mathematical formalism necessary for the diagramatic evaluation of quantum corrections to a conformally invariant field theory for a self-interacting scalar field on a curved manifold with boundary is considered. The evaluation of quantum corrections to the effective action past one-loop necessitates diagramatic techniques. Diagramatic evaluations and higher loop-order renormalisation can be best accomplished on a Riemannian manifold of constant curvature accommodating a boundary of constant extrinsic curvature. In such a context the stated evaluations can be accomplished through a consistent interpretation of the Feynman rules within the spherical formulation of the theory for which the method of images allows. To this effect, the mathematical consequences of such an interpretation are analyzed and the spherical formulation of the Feynman rules on the bounded manifold is, as a result, developed.Comment: 12 pages, references added. To appear in Classical and Quantum Gravit

The relation between magnetic and material arms in models for spiral galaxies

Context. Observations of polarized radio emission show that large-scale (regular) magnetic fields in spiral galaxies are not axisymmetric, but generally stronger in interarm regions. In some nearby galaxies such as NGC 6946 they are organized in narrow magnetic arms situated between the material spiral arms. Aims. The phenomenon of magnetic arms and their relation to the optical spiral arms (the material arms) call for an explanation in the framework of galactic dynamo theory. Several possibilities have been suggested but are not completely satisfactory; here we attempt a consistent investigation. Methods. We use a 2D mean-field dynamo model in the no-z approximation and add injections of small-scale magnetic field, taken to result from supernova explosions, to represent the effects of dynamo action on smaller scales. This injection of small scale field is situated along the spiral arms, where star-formation mostly occurs. Results. A straightforward explanation of magnetic arms as a result of modulation of the dynamo mechanism by material arms struggles to produce pronounced magnetic arms, at least with realistic parameters, without introducing new effects such as a time lag between Coriolis force and {\alpha}-effect. In contrast, by taking into account explicitly the small-scale magnetic field that is injected into the arms by the action of the star forming regions that are concentrated there, we can obtain dynamo models with magnetic structures of various forms that can be compared with magnetic arms. (abbrev). Conclusions. We conclude that magnetic arms can be considered as coherent magnetic structures generated by large-scale dynamo action, and associated with spatially modulated small-scale magnetic fluctuations, caused by enhanced star formation rates within the material arms.Comment: 13 pages, 8 figures, accepted for publication to A&

Preliminary design of a Primary Loop Pump Assembly (PLPA), using electromagnetic pumps

A preliminary design study of flight-type dc conduction-permanent magnetic, ac helical induction, and ac linear induction pumps for circulating 883 K (1130 F) NaK at 9.1 kg/sec (20 lb/sec) is described. Various electromagnetic pump geometrics are evaluated against hydraulic performance, and the effects of multiple windings and numbers of pumps per assembly on overall reliability were determined. The methods used in the electrical-hydraulic, stress, and thermal analysis are discussed, and the high temperature electrical materials selected for the application are listed

The EU water framework directive twenty years on: Introducing the special issue

Twenty years ago, the European Union launched one of its flagship environmental regulations, the Water Framework Directive (WFD). Since its inception in 2000, the WFD has been a guiding light for water professionals within and beyond the EU; it has pioneered ecological standards for water quality, cycles of river basin management planning, participatory forms of water governance, novel economic instruments, and a recurrent assessment regime. At the same time, the WFD has-by virtue of the far-reaching nature of its interventions-aroused political resistance and encountered bureaucratic lethargy; together with many other factors, these have significantly limited its positive impact on the aquatic environment. This Special Issue looks back over the past 20 years to assess what the WFD has achieved, where it has fallen short of expectations, and why. In this introductory piece, the guest editors set the scene and summarise the key findings of the 12 subsequent papers in terms of 6 processes that are characteristic of the WFD''s trajectory: implementation, indication, incrementation, inspiration, imitation and insubordination

The EU water framework directive twenty years on: Introducing the special issue

Twenty years ago, the European Union launched one of its flagship environmental regulations, the Water Framework Directive (WFD). Since its inception in 2000, the WFD has been a guiding light for water professionals within and beyond the EU; it has pioneered ecological standards for water quality, cycles of river basin management planning, participatory forms of water governance, novel economic instruments, and a recurrent assessment regime. At the same time, the WFD has-by virtue of the far-reaching nature of its interventions-aroused political resistance and encountered bureaucratic lethargy; together with many other factors, these have significantly limited its positive impact on the aquatic environment. This Special Issue looks back over the past 20 years to assess what the WFD has achieved, where it has fallen short of expectations, and why. In this introductory piece, the guest editors set the scene and summarise the key findings of the 12 subsequent papers in terms of 6 processes that are characteristic of the WFD''s trajectory: implementation, indication, incrementation, inspiration, imitation and insubordination

Improved TPB-coated Light Guides for Liquid Argon TPC Light Detection Systems

Scintillation light produced in liquid argon (LAr) must be shifted from 128 nm to visible wavelengths in light detection systems used for liquid argon time-projection chambers (LArTPCs). To date, LArTPC light collection systems have employed tetraphenyl butadiene (TPB) coatings on photomultiplier tubes (PMTs) or plates placed in front of the PMTs. Recently, a new approach using TPB-coated light guides was proposed. In this paper, we report on light guides with improved attenuation lengths above 100 cm when measured in air. This is an important step in the development of meter-scale light guides for future LArTPCs. Improvements come from using a new acrylic-based coating, diamond-polished cast UV transmitting acrylic bars, and a hand-dipping technique to coat the bars. We discuss a model for connecting bar response in air to response in liquid argon and compare this to data taken in liquid argon. The good agreement between the prediction of the model and the measured response in liquid argon demonstrates that characterization in air is sufficient for quality control of bar production. This model can be used in simulations of light guides for future experiments.Comment: 25 pages, 20 figure

Gauge symmetry breaking on orbifolds

We discuss a new method for gauge symmetry breaking in theories with one extra dimension compactified on the orbifold S^1/Z_2. If we assume that fields and their derivatives can jump at the orbifold fixed points, we can implement a generalized Scherk-Schwarz mechanism that breaks the gauge symmetry. We show that our model with discontinuous fields is equivalent to another with continuous but non periodic fields; in our scheme localized lagrangian terms for bulk fields appear.Comment: 6 pages, 2 figures. Talk given at the XXXVIIth Rencontres de Moriond, "Electroweak interactions and unified theories", Les Arcs, France, 9-16 Mar 2002. Minor changes, one reference adde

Gravitational quasinormal modes for Anti-de Sitter black holes

Quasinormal mode spectra for gravitational perturbations of black holes in four dimensional de Sitter and anti-de Sitter space are investigated. The anti-de Sitter case is relevant to the ADS-CFT correspondence in superstring theory. The ADS-CFT correspondence suggests a prefered set of boundary conditions.Comment: 12 pages, 6 figures in ReVTe