Analysis of the 2007/8 Defra Farm Business Survey Energy Module

Key points This study has delivered an invaluable baseline estimate of energy use and greenhouse gas (GHG) emissions on commercial farms in England. Energy use and GHG emissions associated with particular commodities were quantified and results broadly agreed with those derived by Life Cycle Assessment, but with much scatter in the environmental performance of farms.Direct energy use on farms was generally less that indirect (embedded) energy use, except for horticulture, which is dominated by heating fuel use. In contrast, most GHG emissions are incurred on farms, rather than as embedded emissions.Scatter in both environmental and economic performance underlies the somewhat disappointing finding of no clear positive link between farm financial performance and energy use or GHG emissions. However, the mere existence of these ranges shows that there is scope for improvement in both financial and environmental performance and that there is no apparent barrier for both to be achievable in harmony. The recording of such farm-level energy data is essential for the future, as it should enable improvements to be made in efficiency of energy use. The improved UK agricultural GHG inventory will depend on high quality energy data on agricultural activities. This study will be invaluable in identifying the level of detail needed. Future data requirements include: contractor work rates and fuel use per unit area and per unit time, fertiliser and pesticide use by brand name, enhanced output data, especially animal live weights, and horticultural produce recorded by weight rather than by value

The Capability Approach for Medical Education

The capability approach, with its origins in economic and human development work, has a focus on the freedom of persons to make choices about how they wish to lead a valued life. There has been increasing recognition within general education that the capability approach offers a theoretical and practical framework to both implement and evaluate educational interventions that are designed to increase social justice, such as widening participation. There is great potential for the capability approach to also offer medical education a creative way for changing and evaluating curricula, with an emphasis on the teacher facilitating students to achieve their potential by recognising their aspirations and challenging the constraining factors to achieve their aspirations

Measurement of the electron's electric dipole moment using YbF molecules: methods and data analysis

We recently reported a new measurement of the electron's electric dipole moment using YbF molecules [Nature 473, 493 (2011)]. Here, we give a more detailed description of the methods used to make this measurement, along with a fuller analysis of the data. We show how our methods isolate the electric dipole moment from imperfections in the experiment that might mimic it. We describe the systematic errors that we discovered, and the small corrections that we made to account for these. By making a set of additional measurements with greatly exaggerated experimental imperfections, we find upper bounds on possible uncorrected systematic errors which we use to determine the systematic uncertainty in the measurement. We also calculate the size of some systematic effects that have been important in previous electric dipole moment measurements, such as the motional magnetic field effect and the geometric phase, and show them to be negligibly small in the present experiment. Our result is consistent with an electric dipole moment of zero, so we provide upper bounds to its size at various confidence levels. Finally, we review the prospects for future improvements in the precision of the experiment.Comment: 35 pages, 15 figure

How do farm models compare when estimating greenhouse gas emissions from dairy cattle production?

The European Union Effort Sharing Regulation (ESR) will require a 30% reduction in greenhouse gas (GHG) emissions by 2030 compared with 2005 from the sectors not included in the European Emissions Trading Scheme, including agriculture. This will require the estimation of current and future emissions from agriculture, including dairy cattle production systems. Using a farm-scale model as part of a Tier 3 method for farm to national scales provides a more holistic and informative approach than IPCC (2006) Tier 2 but requires independent quality control. Comparing the results of using models to simulate a range of scenarios that explore an appropriate range of biophysical and management situations can support this process by providing a framework for placing model results in context. To assess the variation between models and the process of understanding differences, estimates of GHG emissions from four farm-scale models (DairyWise, FarmAC, HolosNor and SFARMMOD) were calculated for eight dairy farming scenarios within a factorial design consisting of two climates (cool/dry and warm/wet)×two soil types (sandy and clayey)×two feeding systems (grass only and grass/maize). The milk yield per cow, follower:cow ratio, manure management system, nitrogen (N) fertilisation and land area were standardised for all scenarios in order to associate the differences in the results with the model structure and function. Potential yield and application of available N in fertiliser and manure were specified separately for grass and maize. Significant differences between models were found in GHG emissions at the farm-scale and for most contributory sources, although there was no difference in the ranking of source magnitudes. The farm-scale GHG emissions, averaged over the four models, was 10.6 t carbon dioxide equivalents (CO2e)/ha per year, with a range of 1.9 t CO2e/ha per year. Even though key production characteristics were specified in the scenarios, there were still significant differences between models in the annual milk production per ha and the amounts of N fertiliser and concentrate feed imported. This was because the models differed in their description of biophysical responses and feedback mechanisms, and in the extent to which management functions were internalised. We conclude that comparing the results of different farm-scale models when applied to a range of scenarios would build confidence in their use in achieving ESR targets, justifying further investment in the development of a wider range of scenarios and software tools

The nuclear Schiff moment and time invariance violation in atoms

Parity and time invariance violating (P,T-odd) nuclear forces produce P,T-odd nuclear moments. In turn, these moments can induce electric dipole moments (EDMs) in atoms through the mixing of electron wavefunctions of opposite parity. The nuclear EDM is screened by atomic electrons. The EDM of an atom with closed electron subshells is induced by the nuclear Schiff moment. Previously the interaction with the Schiff moment has been defined for a point-like nucleus. No problems arise with the calculation of the electron matrix element of this interaction as long as the electrons are considered to be non-relativistic. However, a more realistic model obviously involves a nucleus of finite-size and relativistic electrons. In this work we have calculated the finite nuclear-size and relativistic corrections to the Schiff moment. The relativistic corrections originate from the electron wavefunctions and are incorporated into a ``nuclear'' moment, which we term the local dipole moment. For mercury these corrections amount to about 25%. We have found that the natural generalization of the electrostatic potential of the Schiff moment for a finite-size nucleus corresponds to an electric field distribution which, inside the nucleus, is well approximated as constant and directed along the nuclear spin, and outside the nucleus is zero. Also in this work the plutonium atomic EDM is estimated.Comment: 16 pages, 1 figure, minor misprints correcte

Clinical diagnostic decision-making in real life contexts: A trans-theoretical approach for teaching: AMEE Guide No. 95

Making an accurate clinical diagnosis is an essential skill for all medical students and doctors, with important implications for patient safety. Current approaches for teaching how to make a clinical diagnosis tend to lack the complexity that faces clinicians in real-life contexts. In this Guide, we propose a new trans-theoretical model for teaching how to make an appropriate clinical diagnosis that can be used by teachers as an additional technique to their current approach. This educational model integrates situativity theory, dual-information processing theory and socio-cognitive theory. Mapping and microanalysis help the teacher to identify the main processes involved in making an accurate clinical diagnosis, so that feedback can be provided that is focused on improving key aspects of the skill. An essential aspect of using the new educational model is the role of the experienced clinical teacher in making judgments about the appropriateness of the learner's attempts to make a clinical diagnosis

Restrictions impeding web-based courses: a survey of publishers' variation in authorising access to high quality on-line literature

BACKGROUND: Web-based delivery of educational programmes is becoming increasingly popular and is expected to expand, especially in medicine. The successful implementation of these programmes is reliant on their ability to provide access to web based materials, including high quality published work. Publishers' responses to requests to access health literature in the context of developing an electronic Master's degree course are described. METHODS: Two different permission requests were submitted to publishers. The first was to store an electronic version of a journal article, to which we subscribe, on a secure password protected server. The second was to reproduce extracts of published material on password protected web pages and CD Rom. RESULTS: Eight of 16 publishers were willing to grant permission to store electronic versions of articles without levying charges additional to the subscription. Twenty of 35 publishers gave permission to reproduce extracts of published work at no fee. Publishers' responses were highly variable to the requests for access to published material. This may be influenced by vague terminology within the 'fair dealing' provision in the copyright legislation, which seems to leave it open to individual interpretation. Considerable resource costs were incurred by the exercise. Time expended included those incurred by us: research to identify informed representatives within the publishing organisation, request 'chase-ups' and alternative examples being sought if publishers were uncooperative; and the publisher when dealing with numerous permission requests. Financial costs were also incurred by both parties through additional staffing and paperwork generated by the permission process, the latter including those purely borne by educators due to the necessary provision of photocopy 'course packs' when no suitably alternative material could be found if publishers were uncooperative. Finally we discuss the resultant bias in material towards readily available electronic resources as a result of publisher's uncooperative stance and encourage initiatives that aim to improve open electronic access. CONCLUSIONS: The permission request process has been expensive and has resulted in reduced access for students to the relevant literature. Variations in the responses from publishers suggest that for educational purposes common policies could be agreed and unnecessary restrictions removed in the future

“Making a difference” – Medical students’ opportunities for transformational change in health care and learning through quality improvement projects

Background Quality improvement is increasingly becoming an essential aspect of the medical curriculum, with the intention of improving the health care system to provide better health care. The aim of this study was to explore undergraduate medical students’ experiences of their involvement in quality improvement projects during a district health rotation. Methods Student group reports from rotations in learning centres of the University of Pretoria in Mpumalanga Province, South Africa were analysed for the period 2012 to 2015. Interviews were conducted with health care providers at four learning centres in 2013. Results Three main themes were identified: (1) ‘Situated learning’, describing students’ exposure to the discrepancies between ideal and reality in a real-life situation and how they learned to deal with complex situations, individually and as student group; (2) ‘Facing dilemmas’, describing how students were challenged about the non-ideal reality; (3) ‘Making a difference’, describing the impact of the students’ projects, with greater understanding of themselves and others through working in teams but also making a change in the health care system. Conclusion Quality improvement projects can provide an opportunity for both the transformation of health care and for transformative learning, with individual and ‘collective’ self-authorship