47 resultados para MARC records
em CentAUR: Central Archive University of Reading - UK
Resumo:
Temporal and spatial patterns of soil water content affect many soil processes including evaporation, infiltration, ground water recharge, erosion and vegetation distribution. This paper describes the analysis of a soil moisture dataset comprising a combination of continuous time series of measurements at a few depths and locations, and occasional roving measurements at a large number of depths and locations. The objectives of the paper are: (i) to develop a technique for combining continuous measurements of soil water contents at a limited number of depths within a soil profile with occasional measurements at a large number of depths, to enable accurate estimation of the soil moisture vertical pattern and the integrated profile water content; and (ii) to estimate time series of soil moisture content at locations where there are just occasional soil water measurements available and some continuous records from nearby locations. The vertical interpolation technique presented here can strongly reduce errors in the estimation of profile soil water and its changes with time. On the other hand, the temporal interpolation technique is tested for different sampling strategies in space and time, and the errors generated in each case are compared.
Resumo:
Accurate estimation of the soil water balance (SWB) is important for a number of applications (e.g. environmental, meteorological, agronomical and hydrological). The objective of this study was to develop and test techniques for the estimation of soil water fluxes and SWB components (particularly infiltration, evaporation and drainage below the root zone) from soil water records. The work presented here is based on profile soil moisture data measured using dielectric methods, at 30-min resolution, at an experimental site with different vegetation covers (barley, sunflower and bare soil). Estimates of infiltration were derived by assuming that observed gains in the soil profile water content during rainfall were due to infiltration. Inaccuracies related to diurnal fluctuations present in the dielectric-based soil water records are resolved by filtering the data with adequate threshold values. Inconsistencies caused by the redistribution of water after rain events were corrected by allowing for a redistribution period before computing water gains. Estimates of evaporation and drainage were derived from water losses above and below the deepest zero flux plane (ZFP), respectively. The evaporation estimates for the sunflower field were compared to evaporation data obtained with an eddy covariance (EC) system located elsewhere in the field. The EC estimate of total evaporation for the growing season was about 25% larger than that derived from the soil water records. This was consistent with differences in crop growth (based on direct measurements of biomass, and field mapping of vegetation using laser altimetry) between the EC footprint and the area of the field used for soil moisture monitoring. Copyright (c) 2007 John Wiley & Sons, Ltd.
Resumo:
In this article I provide a critical account of the 'placing' of England's M1 motor-way. I start by critiquing Marc Auge's anthropological writings on 'non-places' which have provided a common point of reference for academics discussing spaces of travel, consumption and exchange in the contemporary world. I argue that Auge's ethnology of supermodernity results in a rather partial account of these sites, that he overstates the novelty of contemporary experiences of these spaces, and that he fails to acknowledge the heterogeneity and materiality of the social networks bound up with the production of non-places/places. I suggest that, rather than focusing on the presences and absences associated with the polarities of place and non-place, academics should examine the multiple, partial, dynamic and relational 'placings' which arise through the diverse performances and movements associated with travel, consumption and exchange. I then trace the topologies of England's M1 motorway, examining some of the different ways in which the motorway has been assembled, performed and placed over the past 45 years.
Resumo:
Introduction A high saturated fatty acid intake is a well recognized risk factor for coronary heart disease development. More recently a high intake of n-6 polyunsaturated fatty acids (PUFA) in combination with a low intake of the long chain n-3 PUFA, eicosapentaenoic acid and docosahexaenoic acid has also been implicated as an important risk factor. Aim To compare total dietary fat and fatty acid intake measured by chemical analysis of duplicate diets with nutritional database analysis of estimated dietary records, collected over the same 3-day study period. Methods Total fat was analysed using soxhlet extraction and subsequently the individual fatty acid content of the diet was determined by gas chromatography. Estimated dietary records were analysed using a nutrient database which was supplemented with a selection of dishes commonly consumed by study participants. Results Bland & Altman statistical analysis demonstrated a lack of agreement between the two dietary assessment techniques for determining dietary fat and fatty acid intake. Conclusion The lack of agreement observed between dietary evaluation techniques may be attributed to inadequacies in either or both assessment techniques. This study highlights the difficulties that may be encountered when attempting to accurately evaluate dietary fat intake among the population.
Resumo:
Identifying a periodic time-series model from environmental records, without imposing the positivity of the growth rate, does not necessarily respect the time order of the data observations. Consequently, subsequent observations, sampled in the environmental archive, can be inversed on the time axis, resulting in a non-physical signal model. In this paper an optimization technique with linear constraints on the signal model parameters is proposed that prevents time inversions. The activation conditions for this constrained optimization are based upon the physical constraint of the growth rate, namely, that it cannot take values smaller than zero. The actual constraints are defined for polynomials and first-order splines as basis functions for the nonlinear contribution in the distance-time relationship. The method is compared with an existing method that eliminates the time inversions, and its noise sensitivity is tested by means of Monte Carlo simulations. Finally, the usefulness of the method is demonstrated on the measurements of the vessel density, in a mangrove tree, Rhizophora mucronata, and the measurement of Mg/Ca ratios, in a bivalve, Mytilus trossulus.
Resumo:
Background: Currently, all pharmacists and technicians registered with the Royal Pharmaceutical Society of Great Britain must complete a minimum of nine Continuing Professional Development (CPD) record (entries) each year. From September 2010 a new regulatory body, the General Pharmaceutical Council, will oversee the regulation (including revalidation) of all pharmacy registrants in Great Britain. CPD may provide part of the supporting evidence that a practitioner submits to the regulator as part of the revalidation process. Gaps in knowledge necessitated further research to examine the usefulness of CPD in a pharmacy revalidation Project aims: The overall aims of this project were to summarise pharmacy professionals’ past involvement in CPD, examine the usability of current CPD entries for the purpose of revalidation, and to examine the impact of ‘revalidation standards’ and a bespoke Outcomes Framework on the conduct and construction of CPD entries for future revalidation of pharmacy professionals. We completed a comprehensive review of the literature, devised, validated and tested the impact of a new CPD Outcomes Framework and related training material in an empirical investigation involving volunteer pharmacy professionals and also spoke with our participants to bring meaning and understanding to the process of CPD conduct and recording and to gain feedback on the study itself. Key findings: The comprehensive literature review identified perceived barriers to CPD and resulted in recommendations that could potentially rectify pharmacy professionals’ perceptions and facilitate participation in CPD. The CPD Outcomes Framework can be used to score CPD entries Compared to a control (CPD and ‘revalidation standards’ only), we found that training participants to apply the CPD Outcomes Framework resulted in entries that scored significantly higher in the context of a quantitative method of CPD assessment. Feedback from participants who had received the CPD Outcomes Framework was positive and a number of useful suggestions were made about improvements to the Framework and related training. Entries scored higher because participants had consciously applied concepts linked to the CPD Outcomes Framework whereas entries scored low where participants had been unable to apply the concepts of the Framework for a variety of reasons including limitations posed by the ‘Plan & Record’ template. Feedback about the nature of the ‘revalidation standards’ and their application to CPD was not positive and participants had not in the main sought to apply the standards to their CPD entries – but those in the intervention group were more likely to have referred to the revalidation standards for their CPD. As assessors, we too found the process of selecting and assigning ‘revalidation standards’ to individual CPD entries burdensome and somewhat unspecific. We believe that addressing the perceived barriers and drawing on the facilitators will help deal with the apparent lack of engagement with the revalidation standards and have been able to make a set of relevant recommendations. We devised a model to explain and tell the story of CPD behaviour. Based on the concepts of purpose, action and results, the model centres on explaining two types of CPD behaviour, one following the traditional CE pathway and the other a more genuine CPD pathway. Entries which scored higher when we applied the CPD Outcomes Framework were more likely to follow the CPD pathway in the model above. Significant to our finding is that while participants following both models of practice took part in this study, the CPD Outcomes Framework was able to change people’s CPD behaviour to make it more inline with the CPD pathway. The CPD Outcomes Framework in defining the CPD criteria, the training pack in teaching the basis and use of the Framework and the process of assessment in using the CPD Outcomes Framework, would have interacted to improve participants’ CPD through a collective process. Participants were keen to receive a curriculum against which certainly CE-type activities could be conducted and another important observation relates to whether CE has any role to play in pharmacy professionals’ revalidation. We would recommend that the CPD Outcomes Framework is used in the revalidation of pharmacy professionals in the future provided the requirement to submit 9 CPD entries per annum is re-examined and expressed more clearly in relation to what specifically participants are being asked to submit – i.e. the ratio of CE to CPD entries. We can foresee a benefit in setting more regular intervals which would act as deadlines for CPD submission in the future. On the whole, there is value in using CPD for the purpose of pharmacy professionals’ revalidation in the future.