19 research outputs found
Plasma creatinine in dogs: intra- and inter-laboratory variation in 10 European veterinary laboratories
<p>Abstract</p> <p>Background</p> <p>There is substantial variation in reported reference intervals for canine plasma creatinine among veterinary laboratories, thereby influencing the clinical assessment of analytical results. The aims of the study was to determine the inter- and intra-laboratory variation in plasma creatinine among 10 veterinary laboratories, and to compare results from each laboratory with the upper limit of its reference interval.</p> <p>Methods</p> <p>Samples were collected from 10 healthy dogs, 10 dogs with expected intermediate plasma creatinine concentrations, and 10 dogs with azotemia. Overlap was observed for the first two groups. The 30 samples were divided into 3 batches and shipped in random order by postal delivery for plasma creatinine determination. Statistical testing was performed in accordance with ISO standard methodology.</p> <p>Results</p> <p>Inter- and intra-laboratory variation was clinically acceptable as plasma creatinine values for most samples were usually of the same magnitude. A few extreme outliers caused three laboratories to fail statistical testing for consistency. Laboratory sample means above or below the overall sample mean, did not unequivocally reflect high or low reference intervals in that laboratory.</p> <p>Conclusions</p> <p>In spite of close analytical results, further standardization among laboratories is warranted. The discrepant reference intervals seem to largely reflect different populations used in establishing the reference intervals, rather than analytical variation due to different laboratory methods.</p
Multi-Sine EIS for Early Detection of PEMFC Failure Modes
Electrochemical impedance spectroscopy (EIS) is a powerful technique that can be used to detect small changes in electrochemical systems and subsequently identify the source of the change. While promising, analysis is often non-intuitive and time-consuming, where collection times of a single EIS spectrum can reach several minutes. To circumvent the long collection times associated with traditional EIS measurements, a multi-sine EIS technique was proposed in which the simultaneous application of many frequencies can reduce the acquisition time to less than a minute. This shortened acquisition time opens the possibility to use multi-sine EIS as a real-time diagnostic tool for monitoring the state-of-health of commercial fuel cell systems. In this work, a single-cell proton exchange membrane fuel cell (PEMFC) was characterised using multi-sine EIS, by establishing steady-state impedance response under baseline conditions before systematically changing operating conditions and monitoring the dynamic changes of the impedance response. Our initial results demonstrate that full multi-sine EIS spectra, encompassing a frequency range from 50 kHz to 0.5 Hz, can be collected and analysed using simple equivalent circuit models in 50 s. It is shown that this timeframe is sufficiently short to capture the dynamic response of the fuel cell in response to changing operating conditions, thereby validating the use of multi-sine EIS as a diagnostic technique for in-situ monitoring and fault detection during fuel cell operation.publishedVersio
Confirmatory Factor Analysis of Warr, Cook, and Wall's (1979) Job Satisfaction Scale
Warr, Cook, and Wall's Job Satisfaction Scale (JSS) is a widely used measure of job satisfaction in industrial/organisational (I/O) psychology research and practice. However, the factor structure has not been adequately explored, with two-factor and three-factor solutions previously proposed. This study tested the factor structure of the JSS using robust analysis methods on data gathered from a convenience sample of 381 (females=264, males=116) Australian employees. Confirmatory factor analyses supported a hierarchical three-factor model of job satisfaction in terms of model adequacy coefficients; however, the three factors were highly correlated, thereby rendering a multifactorial approach to the JSS untenable. The results support the continued use of an overall score of job satisfaction when using this measure in I/O psychology research and practice. Further testing of the structure is recommended within a range of employment sectors, as the assumed multifactorial structure of the JSS common in the literature was not supported by the current study
Decarbonisation of transport: options and challenges
This EASAC report reviews options for reducing greenhouse gas (GHG) emissions from European transport. It argues for stronger policies to bridge the gap between the GHG emission reductions that will be delivered by current policies and the levels needed to limit global warming to less than 2°C or even 1.5°C (Paris Agreement). The report focusses on road transport because, in the EU, this contributes 72% of transport GHG emissions. EASAC recommends a combination of transitional measures for the next 10-15 years and sustainable measures for the long term, based on a three level policy framework: avoid and contain demand for transport services; shift passengers and freight to transport modes with lower emissions (trains, buses and ships); and improve performance through vehicle design, more efficient powertrains and replacing fossil fuels with sustainable energy carriers including low-carbon electricity, hydrogen and synthetic fuels. Opportunities for the EU to strengthen its industrial competitiveness and create high quality jobs are also discussed
Decarbonisation of transport: options and challenges
This EASAC report reviews options for reducing greenhouse gas (GHG) emissions from European transport. It argues for stronger policies to bridge the gap between the GHG emission reductions that will be delivered by current policies and the levels needed to limit global warming to less than 2\xc2\xb0C or even 1.5\xc2\xb0C (Paris Agreement). The report focusses on road transport because, in the EU, this contributes 72% of transport GHG emissions. EASAC recommends a combination of transitional measures for the next 10-15 years and sustainable measures for the long term, based on a three level policy framework: avoid and contain demand for transport services; shift passengers and freight to transport modes with lower emissions (trains, buses and ships); and improve performance through vehicle design, more efficient powertrains and replacing fossil fuels with sustainable energy carriers including low-carbon electricity, hydrogen and synthetic fuels. Opportunities for the EU to strengthen its industrial competitiveness and create high quality jobs are also discussed
The harmonized INFOGEST in vitro digestion method: From knowledge to action
Within the active field of in vitro digestion in food research, the COST Action INFOGEST aimed to harmonize in vitro protocols simulating human digestion on the basis of physiologically inferred conditions. A harmonized static in vitro digestion (IVD) method was recently published as a primary output from this network. To validate this protocol, inter-laboratory trials were conducted within the INFOGEST network. A first study was performed using skim milk powder (SMP) as a model food and served to compare the different in-house digestion protocols used among the INFOGEST members. In a second inter-laboratory study applying the harmonized protocol, the degree of consistency in protein hydrolysis was investigated. Analysis of the hydrolyzed proteins, after the gastric and intestinal phases, showed that caseins were mainly hydrolyzed during the gastric phase, whereas β-lactoglobulin was, as previously shown, resistant to pepsin. Moreover, generation of free amino acids occurred mainly during the intestinal phase.The study also showed that a few critical steps were responsible for the remaining inter-laboratory variability. The largest deviations arose from the determination of pepsin activity. Therefore, this step was further clarified, harmonized, and implemented in a third inter-laboratory study.The present work gives an overview of all three inter-laboratory studies, showing that the IVD INFOGEST method has led to an increased consistency that enables a better comparability of in vitro digestion studies in the future
Real-Time Sensor Servoing using Line-of-Sight Path Generation and Tool Orientation Control
Multi-Sine EIS for Early Detection of PEMFC Failure Modes
Electrochemical impedance spectroscopy (EIS) is a powerful technique that can be used to detect small changes in electrochemical systems and subsequently identify the source of the change. While promising, analysis is often non-intuitive and time-consuming, where collection times of a single EIS spectrum can reach several minutes. To circumvent the long collection times associated with traditional EIS measurements, a multi-sine EIS technique was proposed in which the simultaneous application of many frequencies can reduce the acquisition time to less than a minute. This shortened acquisition time opens the possibility to use multi-sine EIS as a real-time diagnostic tool for monitoring the state-of-health of commercial fuel cell systems. In this work, a single-cell proton exchange membrane fuel cell (PEMFC) was characterised using multi-sine EIS, by establishing steady-state impedance response under baseline conditions before systematically changing operating conditions and monitoring the dynamic changes of the impedance response. Our initial results demonstrate that full multi-sine EIS spectra, encompassing a frequency range from 50 kHz to 0.5 Hz, can be collected and analysed using simple equivalent circuit models in 50 s. It is shown that this timeframe is sufficiently short to capture the dynamic response of the fuel cell in response to changing operating conditions, thereby validating the use of multi-sine EIS as a diagnostic technique for in-situ monitoring and fault detection during fuel cell operation