Real and Virtual Nucleon Compton Scattering in the Perturbative Limit

We present the results of calculations analyzing nucleon Compton scattering to lowest order using perturbative QCD (pQCD) methods. Two scenarios are considered: (1) the incoming photon is real; and (2) the incoming photon is virtual. The case of a real photon has been previously analyzed at least 5 times using pQCD, but no two results are in agreement. Here it is shown that our result agrees with that of Brooks and Dixon published in 2000. The case of a virtual photon has been previously analyzed only once using pQCD. However, doubt has been cast on the validity of that result. The results presented here for virtual photon are believed to be more reliable. Some consideration is given of how to compare these results with experiment. Following the lead of Brooks and Dixon, for the proton, this involves normalizing the cross section using the Dirac proton form factor, which we also calculate. Finally, there is a comparison of our results with recent experiments.Comment: 36 pages, 11 figure

Temperature-dependent errors in nuclear lattice simulations

We study the temperature dependence of discretization errors in nuclear lattice simulations. We find that for systems with strong attractive interactions the predominant error arises from the breaking of Galilean invariance. We propose a local "well-tempered" lattice action which eliminates much of this error. The well-tempered action can be readily implemented in lattice simulations for nuclear systems as well as cold atomic Fermi systems.Comment: 33 pages, 17 figure

The value and meaning of significance in the planning system for the protection of historic parks and gardens in England

In England, parks and gardens are an acknowledged part of the historic environment, for which the principal protection mechanism is the planning system. Since 2010, that protection has relied primarily on the application of a policy predicated on the identification and conservation of a historic asset’s ‘significance’, or special interest. This research evaluates the concept of significance as a basis for protecting historic parks and gardens in England, and assesses the effectiveness of the planning system in sustaining that significance. It adopts a case study approach to investigate the handling of a planning application for a development proposal in each of three registered parks and gardens, involving site assessments, documentary review, and semi-structured interviews. This is supplemented by a nationwide questionnaire survey of local planning authorities, interviews with high-level stakeholders, and analysis of relevant policy and legislation. The research finds that significance-based policy is not well understood, and that its potential is unfulfilled in practice. Parks and gardens themselves are found to be relatively neglected as heritage assets in both conservation and research. The research concludes that the planning system could be effective in sustaining the significance of historic parks and gardens, but currently is not. The contributions to knowledge made by the research include the review of planning practice in respect of parks and gardens (the first since 1992), the development of a typology of interests to inform the definition of significance, and a model to guide the process of definition. A further contribution – with the potential for wider application – is a theoretical model of the influences on the construction of significance in the decision-making process on planning applications. Recommendations arising from the research include a call for improved use of existing protection mechanisms, and for the production of guidance for practitioners to support this

Reducing Harvesting Costs Using Windrow Grazing

Dr. Robert Taylor, of Colorado State University, at the 1995 NCA meeting stated, …after the current cycle 30% of today’s beef producers will not be in business. A colleague, Paul Gehno, now with the King Ranch in Florida, once stated, the industry that emerges from this down phase will be leaner, smaller and more competitive. Another quote, of which I am afraid I do not have the author states, in times of change, learners inherit the earth while the learned find themselves beautifully equipped to work in a world that no longer exists. We live in a world of change to which the livestock industry is certainly not immune. The next few years will be critical as far as determining those of us that will remain in the beef business for the future. As stated in the last quote, if we are not willing to learn, to change, or to adapt, we will be left behind while the rest of the beef industry moves forward. There are presently a number of areas that are critical to the survival of the beef industry, let alone our own survival. They are food safety, health & nutrition, palatability, consistency, value or cost, and convenience. All of these determine the demand for beef and we, as producers, have a major influence on all but convenience. Through our selection of breeding animals and management practices we affect the first five factors while the latter factor, convenience, is somewhat out of our hands. Of these, the most significant, and the area which we can have the most influence on, is the cost of producing a pound of beef

Questions of quality in repositories of open educational resources: a literature review

Open educational resources (OER) are teaching and learning materials which are freely available and openly licensed. Repositories of OER (ROER) are platforms that host and facilitate access to these resources. ROER should not just be designed to store this content – in keeping with the aims of the OER movement, they should support educators in embracing open educational practices (OEP) such as searching for and retrieving content that they will reuse, adapt or modify as needed, without economic barriers or copyright restrictions. This paper reviews key literature on OER and ROER, in order to understand the roles ROER are said or supposed to fulfil in relation to furthering the aims of the OER movement. Four themes which should shape repository design are identified, and the following 10 quality indicators (QI) for ROER effectiveness are discussed: featured resources; user evaluation tools; peer review; authorship of the resources; keywords of the resources; use of standardised metadata; multilingualism of the repositories; inclusion of social media tools; specification of the creative commons license; availability of the source code or original files. These QI form the basis of a method for the evaluation of ROER initiatives which, in concert with considerations of achievability and long-term sustainability, should assist in enhancement and development. Keywords: open educational resources; open access; open educational practice; repositories; quality assuranc

On the Rate-dependent Plasticity Modelling of Unidirectional Fibre-reinforced Polymeric Matrix Composites

Three different approaches to plasticity are investigated to model the experimentally-observed non-linear behaviour of unidirectional fibre-reinforced polymeric matrix materials. The first and simplest approach consists on assuming independent one-dimensional rate-dependent plasticity on in-plane (12) and through-thickness longitudinal (13) shear components of the Cauchy stress tensor. The second, employs a 3D extension of the plane stress Hill'48 anisotropic plastic surface. The third and the last is formulated as a quadratic yield function inspired by Puck's fracture initiation criterion. It searches for a plastic localisation plane in which a certain combination of normal and shear stresses is maximum. Numerical simulations are conducted to analyse the off-axis compression behaviour of carbon fibre reinforced epoxy composite under varying loading rates. The afore-mentioned three different approaches are explored with an aim to predict the experimentally-observed non-linear response of such composites. The model parameters are determined using a deterministic inverse modelling strategy employing an iterative domain reduction optimisation technique. As far as the experiments are concerned, the quasi-static and medium rate tests were carried out in universal testing machines, while the experiments at high rate were conducted in a Split Hopkinson Pressure Bar system. The effectiveness in terms of accuracy and robustness of the three approaches are discussed

Monitoring and controlling bank risk: does risky debt serve any purpose?

To examine whether mandating banks to issue subordinated debt would enhance market monitoring and control risk-taking, the authors extract the credit-spread curve for each banking firm in their sample. After controlling for changes in market and liquidity variables, they find that changes in credit spreads do not reflect changes in bank risk variables. The result is robust to firm type, examination rating, size, leverage, and profitability, as well as to different model specifications. They also find that issuing subordinated debt does not alter banks' risk-taking behavior. They conclude that a mandatory subordinated debt requirement for banks is unlikely to provide the intended benefits of enhancing risk-monitoring or controlling risk-taking.Bank capital ; Risk

On credit spread slopes and predicting bank risk

The authors examine whether credit-spread curves, engendered by a mandatory subordinated-debt requirement for banks, would help predict bank risk. They extract the credit-spread curves each quarter for each bank in our sample, and analyze the information content of credit-spread slopes. They find that credit-spread slopes are significant predictors of future credit spreads. However, credit-spread slopes do not provide significant additional information on future bank-risk variables, over and above other bank-specific and market-wide information.Bank capital ; Risk

Electroweak Symmetry Breaking From Monopole Condensation

We examine models where massless chiral fermions with both "electric" and "magnetic" hypercharges could form condensates. When some of the fermions are also electroweak doublets such condensates can break the electroweak gauge symmetry down to electromagnetism in the correct way. Since ordinary hypercharge is weakly coupled at the TeV scale, magnetic hypercharge is strongly coupled and can potentially drive the condensation. Such models are similar to technicolor, but with hypercharge playing the role of the technicolor gauge group, so the standard model gauge group breaks itself. A heavy top mass can be generated via the Rubakov-Callan effect and could thus decouple the scale of flavor physics from the electroweak scale.Comment: Absence of pseudo-Goldstone bosons explain, discussion of the role of flavor physics clarified, other minor changes. References adde