689 research outputs found
Electro-chemical machining
This report introduces the reader to the process and to the
requirements which must be considered for its installation on the shop
floor. Although only electro-chemical shaping is dealt with, many of
the parameters investigated are fundamental to other configurations.
The machining characteristics of several high strength alloys and die
steels have been investigated; also of aluminium and mild steel.
Electrolyte heating effects and the physical attributes of the machined
surface have been considered. Electrode and workpiece shapes have been
simulated for static field examinations and these followed by investigations
under dynamic machining conditions
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Exploring practical approaches to maximising data quality in electronic healthcare records in the primary care setting and associated benefits
Exploiting the information contained within electronic healthcare records (EHR) data will be key to addressing major challenges to public health both nationally and globally, ultimately offering a means of maximising efficiency and equality in care. There are, however, significant challenges in using EHRs effectively and particularly in ensuring the quality of data recorded. Incorrect or missing data could render records as useless or indeed misleading such that conclusions drawn from the data could have a negative impact. Amongst other difficulties, recording data can be time consuming to the extent of conflicting with the GP’s primary focus of patient consultation in an already time-constrained environment. Understanding the requirements of and the demands upon GPs must be central to addressing the issue of data quality (DQ) within EHRs.
As part of on-going work into DQ at the Clinical Practice Research Datalink (CPRD) and in collaboration with the University of Sussex (UoS), a workshop session was held at the SAPC (Society for Academic Primary Care) conference in 2014 with the aim of exploring issues of DQ in primary care EHRs from the perspective of different users of GP data and with particular focus on how and why data is recorded in the first instance. The intended outcome was a furthered understanding of both the challenges and the direct benefits to GPs of ensuring high quality data with a view to establishing a workable approach to recording data and maximising benefits to all users of EHRs
Do investors value payout increases? Evidence from the Canadian income trust sector
Investor response to changes in income trust payouts is measured using the implied cost of capital. As trust units are purchased primarily for the income stream, valuation using discounted cash flow models is appropriate and adverse responses to associated transaction costs are considered unlikely. The data reveal that investors in this sector do not reward the organization for payout growth explicitly; rather financing cost is reduced relative to the trust’s ability to fund an increase, similar to risk premiums in fixed income markets
Integration interrupted: value loss from SIFT taxation
An after-tax value loss ratio compares newly defined SIFT’s to income trusts affected by the taxation change announced on October 31, 2006. The legislation produces after-tax loss of roughly 8% based on 2010 tax rates, approaching 15% for those in higher brackets. Tax integration is incomplete, providing 5% of the loss, but the legislation penalizes the payout of capital gains and return of capital, hampering efforts to determine a clientele result in the sector. Reduction in pre-tax cash flows and additional after-tax loss in valuation, made conversion and privatization of trusts the only viable alternatives when the tax became effective
Quality of recording of diabetes in the UK: how does the GP’s method of coding clinical data affect incidence estimates? Cross-sectional study using the CPRD database
Objective: To assess the effect of coding quality on estimates of the incidence of diabetes in the UK between 1995 and 2014.
Design: A cross-sectional analysis examining diabetes coding from 1995 to 2014 and how the choice of codes (diagnosis codes vs codes which suggest diagnosis) and quality of coding affect estimated incidence.
Setting: Routine primary care data from 684 practices contributing to the UK Clinical Practice Research Datalink (data contributed from Vision (INPS) practices).
Main outcome measure: Incidence rates of diabetes and how they are affected by (1) GP coding and (2) excluding ‘poor’ quality practices with at least 10% incident patients inaccurately coded between 2004 and 2014.
Results: Incidence rates and accuracy of coding varied widely between practices and the trends differed according to selected category of code. If diagnosis codes were used, the incidence of type 2 increased sharply until 2004 (when the UK Quality Outcomes Framework was introduced), and then flattened off, until 2009, after which they decreased. If non-diagnosis codes were included, the numbers continued to increase until 2012. Although coding quality improved over time, 15% of the 666 practices that contributed data between 2004 and 2014 were labelled ‘poor’ quality. When these practices were dropped from the analyses, the downward trend in the incidence of type 2 after 2009 became less marked and incidence rates were higher.
Conclusions: In contrast to some previous reports, diabetes incidence (based on diagnostic codes) appears not to have increased since 2004 in the UK. Choice of codes can make a significant difference to incidence estimates, as can quality of recording. Codes and data quality should be checked when assessing incidence rates using GP data
Evaluating Floor Losses in the Context of QUB Measurements of a Passivhaus Dwelling
Measuring the performance of building fabric is increasingly important as stakeholders wish to compare as-built performance with design expectations. When measuring whole house performance (Heat Transfer Coefficient) heat losses through the floor in slab-on-ground type constructions are intractable and introduce uncertainty into measurements. As such efforts are often made to isolate them from measurements. The QUB method is a practical method of measuring whole house building performance. Previous work has shown floor losses can successfully be isolated from measurement through use of heat flux measurements and additional calculation steps. To further test this isolation procedure, three QUB tests were performed on a slab-on-ground Passivhaus dwelling. Whilst the whole house performance measurements agree with the design performance (all results within 11% of the design) the floor losses measured appear unrealistically high. The conditions of the tests, conducted in late summer and in a highly insulated property, are likely causing the heat flux measurements to capture heat being stored in the floor construction rather than heat being lost from the property. Follow up measurements in more preferable conditions are planned which will assist in determining the cause of these observations
Evolución de los ácidos grasos en el mesocarpo del níspero (Mespilus germanica. L.) a diferentes estados de maduración
The fatty acid composition of medlar (Mespilus germanica L.) varied significantly among the ripening stages sampled at 157, 172 and 187 DAFs (days after full bloom). Twenty-one different fatty acids were detected in preclimacteric fruit and 17 when the climacteric began. Principal fatty acids, determined in medlar fruit harvested from October (157 and 172 DAFs) to November (187 DAF) were mainly palmitic acid (16:0), linoleic acid (18:2n-6), and a-linolenic acid (18:3n-3). While the content of saturated fatty acids [palmitic acid (16:0) and stearic acid (18:0)] increased, the content of the essential polyunsaturated fatty acids [linoleic acid (18:2n-6) and linolenic acid (18:3n-3)] decreased through ripening, in parallel with pulp darkening. The percentage of linoleic acid and a-linolenic acid in ripe, hard fruits was 60.0 and 13.5 % of dry wt at 157 DAF which decreased throughout ripening, remaining at 28.7 and 5.6 % of dry wt, respectively, in the fully softened and darkened pulp. A marked decreases in the double bond index, percentage of unsaturation and the ratio of unsaturation/saturation were also seen throughout the medlar ripening. The contribution of unsaturated fatty acid to the total fatty acid content decreased markedly as the medlar fruit became progressively softer and darkened.La composición en ácidos grasos del níspero (Mespilus germanica L.) varió significativamente entre los estados de maduración muestreados a los 157, 172 y 187 DAFs (días después de la floración). Veinte y un ácidos grasos diferentes fueron detectados en el fruto preclimatérico y 17 cuando comenzó el climaterio. Los ácidos grasos principales encontrados en nísperos, recolectados desde Octubre (157 y 172 DAFs) hasta Noviembre (187 DAF), fueron principalmente ácido palmítico (16:0), ácido linoléico (18:2n-6), y ácido a-linolénico (18:3n-3). En tanto que el contenido en ácidos grasos saturados (ácido palmítico (16:0) y ácido esteárico (18:0)) aumentó, el contenido en ácidos grasos esenciales (ácido linoleico (18:2n-6) y ácido linolénico (18:3n-6)) disminuyó durante la maduración, en paralelo con el oscurecimiento de la pulpa. El porcentaje de ácido linoleico y de ácido a-linolénico en frutos maduros sin reblandecer fue de 60.0 y 13.5 % del peso seco a 157 DAF, disminuyendo durante la maduración, y permaneciendo a 28.7 y 56 % del peso seco, respectivamente, en la pulpa completamente blanda y oscura. También se observó durante la maduración del níspero una marcada disminución en el número de dobles enlaces, en el tanto por ciento de instauración y en la relación instauración / saturación. La contribución de los ácidos grasos insaturados al contenido de ácidos grasos totales disminuyó marcadamente cuando el níspero comenzó progresivamente a reblandecerse y oscurecerse
Party Wall Behaviour and Impact in QUB and Coheating Tests
In situ measurement can enable accurate evaluation of a building’s as-built performance. However, when measuring whole house performance, party walls introduce measurement uncertainty. Subsequently, it is common to “adjust” measurements to isolate heat transfer through party walls. This study explores the behaviour and impact of party walls in QUB and coheating measurements of a semi-detached house, presenting empirical evidence on the validity of these measurements where a party wall is present. Two different party wall heat transfer behaviours were observed through heat flux density measurements. Thermal charging is apparent in QUB tests and the initial stages of coheating. After 48 h of coheating, the party wall has become heat saturated and exhibits stable heat transfer. Consequently, using heat flux density measurements to isolate party wall heat transfer in QUB tests, where thermal saturation has not been achieved, can result in misleading inferences. The coheating and QUB measurements without party wall adjustment are in close agreement, irrespective of differing heating patterns in the neighbouring property. The generalisation of these findings is problematic since they describe the impact of the case study-specific built form and the test conditions. Future work to explore the impact of built form and test conditions is needed
A methodology for creating building energy model occupancy schedules using personal location metadata
Occupants affect energy consumption in buildings by contributing internal heat gains, increasing internal carbon dioxide levels and adapting their behaviour. Estimated occupancy schedules are used in building energy models for regulatory compliance purposes and when empirical data are not available. Metadata, such as personal location data, is now collected and visualised on a global scale and can be used to create more realistic occupancy schedules for non-domestic facilities, such as large retail outlets. This paper describes a protocol for extracting and using freely available metadata to create occupancy schedules that are used as inputs for dynamic simulation models. A sample set of twenty supermarket building models are used to demonstrate the impact metadata schedules have when compared with models using the estimated schedules from regulatory compliance. Metadata can be used to create bespoke occupancy profiles for specific buildings, groups of buildings and building archetypes. This method could also help reduce the gap between predicted and actual performance. In the example models, those using the regulatory compliance schedules underestimated heating demand by approximately 10% and overestimated cooling demand by over 50% when compared to models using the metadata schedules. Although this work focuses on UK facilities, this methodology has scope for global application
Lymph node homing cells biologically enriched for γδ T cells express multiple genes from the T19 repertoire
Sheep γδ T cells have been shown serologically to express T19, a membrane protein of 180-200 kDa which is a member of the scavenger receptor superfamily. Previous work from this laboratory resulted in the detection of a multigene family of T19-like genes in the sheep genome. In this study nucleotide sequences from several T19 genes were determined and are reported along with the corresponding segments of a number of expressed mRNA molecules. A segment of a single sheep T19-like gene was sequenced and these data, along with the corresponding sequences from cloned T19-like cDNA molecules from sheep and cow, were used to design an ollgonucleotide primer system suitable for amplification of corresponding segments of many T19 genes and their cDNAs. Between 30 and 40% of cloned T19 genes were amenable to amplification using the selected primers, and sequence analysis of cloned PCR products confirmed that different T19 genes encode unique amino acid sequences. The expression of multiple T19 genes was established using cDNA molecules obtained from a single sample of sheep lymphocyte mRNA. The possible role of the T19 family of genes is discusse
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