Defining Benchmark Status: An Application using Euro-Area Bonds

The introduction of the euro on 1 January 1999 created the conditions for an integrated government bond market in the euro area. Using a unique data set from the electronic trading platform Euro-MTS, we consider what is the benchmark' in this market. We develop and apply two definitions of benchmark status that differ from the conventional view that the benchmark is the security with lowest yield at a given maturity. Using Granger-causality and cointegration methods, we find a complex pattern of benchmark status in euro-area government bonds.

Evaluation of supply control options for beef

End of project reportThe incomes of Irish cattle farmers benefited greatly from the reform of the CAP for beef and cereals in 1992 and more recently under Agenda 2000. In both of these reforms the institutional support prices were reduced and direct payments (DPs) were used to compensate farmers for the price reduction

Emergent gauge dynamics of highly frustrated magnets

Condensed matter exhibits a wide variety of exotic emergent phenomena such as the fractional quantum Hall effect and the low temperature cooperative behavior of highly frustrated magnets. I consider the classical Hamiltonian dynamics of spins of the latter phenomena using a method introduced by Dirac in the 1950s by assuming they are constrained to their lowest energy configurations as a simplifying measure. Focusing on the kagome antiferromagnet as an example, I find it is a gauge system with topological dynamics and non-locally connected edge states for certain open boundary conditions similar to doubled Chern-Simons electrodynamics expected of a $Z_2$ spin liquid. These dynamics are also similar to electrons in the fractional quantum Hall effect. The classical theory presented here is a first step towards a controlled semi-classical description of the spin liquid phases of many pyrochlore and kagome antiferromagnets and towards a description of the low energy classical dynamics of the corresponding unconstrained Heisenberg models.Comment: Updated with some appendices moved to the main body of the paper and some additional improvements. 21 pages, 5 figure

On the Yang-Mills two-loop effective action with wordline methods

We derive the two-loop effective action for covariantly constant field strength of pure Yang-Mills theory in the presence of an infrared scale. The computation is done in the framework of the worldline formalism, based on a generalization procedure of constructing multiloop effective actions in terms of the bosonic worldline path integral. The two-loop beta-function is correctly reproduced. This is the first derivation in the worldline formulation, and serves as a nontrivial check on the consistency of the multiloop generalization procedure in the worldline formalism.Comment: 8 pages, 4 figure

Inter-ELM evolution of the edge current density profile on the ASDEX upgrade tokamak

The sudden decrease of plasma stored energy and subsequent power deposition on the first wall of a tokamak due to edge localised modes (ELMs) is potentially detrimental to the success of a future fusion reactor. Understanding and control of ELMs is critical for the longevity of these devices and also to maximise their performance. The commonly accepted picture of ELMs posits a critical pressure gradient and current density in the plasma edge, above which coupled magnetohy drodynamic peeling-ballooning modes become unstable. Much analysis has been presented in recent years on the spatial and temporal evolution of the edge pressure gradient. However, the edge current density has typically been overlooked due to the difficulties in measuring this quantity. In this thesis, a novel method of current density recovery is presented, using the equilibrium solver CLISTE to reconstruct a high resolution equilibrium utilising both external magnetic and internal edge kinetic data measured on the ASDEX Upgrade tokamak. The evolution of the edge current density relative to an ELM crash is presented, showing that a resistive delay in the buildup of the current density is unlikely. An uncertainty analysis shows that the edge current density can be determined with an accuracy consistent with that of the kinetic data used. A comparison with neoclassical theory demonstrates excellent agreement be- tween the current density determined by CLISTE and the calculated profiles. Three ELM mitigation regimes are investigated: Type-II ELMs, ELMs sup- pressed by external magnetic perturbations, and Nitrogen seeded ELMs. In the first two cases, the current density is found to decrease as mitigation on- sets, indicating a more ballooning-like plasma behaviour. In the latter case, the flux surface averaged current density can decrease while the local current density increases, providing a mechanism to suppress both the peeling and ballooning modes

Fluctuations in Energy Intake and Fertility in Cattle.

End of Project ReportsReproductive failure in dairy cows results in fewer calves born, lower milk sales, slower genetic progress and consequently, significant financial loss to the industry. Dairy cattle breed improvement programmes have, at least until very recently, focused primarily on increasing the yields of milk or milk solids. The resulting genetic improvement has led to significant increases in milk yield per cow but this increase is now associated with a significant decline in cow reproductive wastage. An important part of the Teagasc research programme in this area is to determine the time at which embryo loss occurs and also to determine whether the extent of the embryo loss is affected by the energy nutrition of the cow and to devise strategies to reduce its extent. This project has focused on the relationship between changes in dietary energy intake near the time of insemination and the extent and pattern of embryo survival. The main results are summarised in this report and detailed results of the several experiments involved have been published in the papers listed at the end of this report. • • 4 The objectives of this project were to determine the effect of changes in energy intake near the time of insemination on embryo loss rate, on the timing of embryo loss and on the possible biological mechanisms involved. Cross bred heifers were provided with either high or low energy intakes that were based on pasture allowances calculated to provide either 0.8 or 2.0 times their maintenance requirements. These energy intakes were allocated for two weeks before and about five weeks after insemination. The effect of the changes in energy intake on embryo loss and on the time at which embryo loss occurred, relative to the time of insemination, was established. Possible associations between embryo loss and blood concentrations of progesterone, NEFAs, insulin and glucose were examined. A sudden reduction from a high to a low energy intake imposed for two weeks from the day of insemination reduced the subsequent embryo survival rate by 30 percentage points to a survival rate of 38%. When energy intake over this same period was either maintained or increased, embryo survival rate remained high (overall mean, 69%), within a range of 65-71%. The time at which embryo loss occurred was established. Embryo survival or pregnancy rates measured on days 14 and 30 after insemination and at full term were 68%, 76% and 72%, respectively. These results provide new information indicating that most embryo loss, at least in heifers, had occurred on or before day 14 after insemination. There was no evidence of any association between the shortterm changes in energy intake either before or after AI and blood progesterone concentration. Neither was there any evidence that the detrimental effect of the sudden reduction in energy intake on embryo survival was mediated through changes in the systemic concentrations of non-esterified fatty acids (NEFAs) or insulin. There was a suggestion, however, that the detrimental effect of the reduced energy intake may operate through a reduction in systemic glucose concentrations.Dairy Levy Farmer Fun

Inter-Country Cost Comparisons in Beef.

End of Project ReportThe purpose of this study was to: • establish the competitiveness of the Irish beef production systems post the 1992 CAP reform • quantify how Irish beef production costs, and cost components, compare with those for the other EU countries • determine the strengths and weaknesses of the Irish production systems

Tree Canopy Change in Coastal Los Angeles, 2009 - 2014

Los Angeles, California is prone to extreme climate events—e.g. drought, wildfires, and floods—that are only expected to increase with climate change. The establishment of green infrastructure, including a stable urban forest, is a strategy to improve resilience not only to these events, but also to contribute to other environmental, social, and economic goals. To this end, cities throughout Los Angeles County have tree planting programs and policies aimed to grow and maintain their urban forests. Despite the policy objectives and management goals of such programs, we know surprisingly little about the spatial distribution of the existing urban forest, how and where the canopy has changed over time, or the composition of the population living in places of canopy change. To examine these questions, we conducted an analysis of the Los Angeles Coast based on land cover data derived from high-resolution aerial imagery and LiDAR. In addition to characterizing the overall percentages of existing and possible tree canopy in 2014, we also characterized the change in tree canopy from 2009 to 2014 with five measures of tree canopy and change: total canopy, persistence, loss, gain, and net change. We used market segmentation data to analyze the relationship between tree canopy and the composition of communities. Results indicated that tree canopy covered about 15% of coastal Los Angeles, but this cover was unevenly distributed throughout the study area. The parcel-level analysis of change indicated that while the canopy did not change much from 2009-2014, the changes that did occur were localized and would have been missed at a coarser scale of analysis. Using geodemographic segments, we found that higher-income lifestyle groups tended to have more tree canopy and less loss over time. Change within land uses was consistent with overall change. These high-resolution, high-accuracy data and analyses can support valuable tools to guide decision-making about urban forests, especially as it relates to social equity