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Horst Spielmann - One of the best experts on this subject based on the ideXlab platform.
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the epiderm Test Protocol for the upcoming ecvam validation study on in vitro skin irritation Tests an assessment of the performance of the optimised Test
Atla-alternatives To Laboratory Animals, 2005Co-Authors: Helena Kandarova, Ingrid Gerner, M Liebsch, E Genschow, Dieter Traue, E Schmidt, Horst SpielmannAbstract:: During the past decade, several validation studies have been conducted on in vitro methods for discriminating between skin irritating and non-irritating chemicals. The reconstructed human skin models, EpiDerm and EPISKIN, provided the most promising results. Based on experience of the similar performance of the two skin models, it was suggested that a common Test Protocol and prediction model should be developed for the prediction of skin irritation potential with the two models. When the EPISKIN Protocol was applied with the EpiDerm model, an acceptable specificity (80%) was achieved, whereas the sensitivity (60%) was low. In 2003, the EPISKIN Protocol was further refined by extending the post-incubation period following exposure to Test chemicals. This extension and additional technical improvements to the EpiDerm Protocol were evaluated with 19 chemicals from the prevalidation study. With the new Test design, high sensitivity (80%) and specificity (78%) were obtained. The statistical probability for correct classifications was high, so the Test was considered to be ready for formal validation. However, since Test optimisation had been conducted with the same Test chemicals as were used in the ECVAM prevalidation study, it was decided that the optimisation of the Protocol had to be verified with a new set of chemicals. Thus, in the current study, 26 additional chemicals (10 rabbit irritants and 16 non-irritants), which had previously been selected and Tested by LOREAL with EPISKIN, were evaluated in three independent experiments with EpiDerm. With this unbalanced Testing set, a specificity of 94%, and a sensitivity of 60% were obtained, while the positive and negative predictivity and accuracy remained almost unchanged (around 80%) in comparison to the in vivo rabbit data. Overall, 45 chemicals (20 irritants and 25 non-irritants) were Tested according to the final Protocol. The resulting high positive (82%) and negative predictive values (79%) confirmed the reliability (accuracy of 80%) of the improved Test Protocol of the EpiDerm model.
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optimisation of the epiderm Test Protocol for the upcoming ecvam validation study on in vitro skin irritation Tests
ALTEX-Alternatives to Animal Experimentation, 2004Co-Authors: Helena Kandarova, Ingrid Gerner, M Liebsch, E Genschow, Dieter Traue, B Slawik, Horst SpielmannAbstract:: An ECVAM-funded prevalidation study (PV) was conducted during 1999 and 2000 to identify in vitro Tests capable of reliably distinguishing between skin irritants (I) and non-irritants (NI) according to European Union risk phrases ("R38" or no classification). The Tests evaluated were EpiDerm, EPISKIN, PREDISKIN, the non-perfused pig ear method, and the mouse skin integrity function Test (SIFT). Whereas reproducibility of the two human skin model Tests and SIFT was acceptable, none of the methods was deemed ready to enter a formal validation study due to their low predictivity. The ECVAM Skin Irritation Task Force therefore suggested improvements of Protocols and prediction models for these Tests. Furthermore, it was agreed that experience gained with the two human-skin models be shared, and a common Protocol should be developed for EpiDerm and EPISKIN (Zuang et al., 2002). When we applied an improved EPISKIN Protocol (Portes et al., 2002) to the EpiDerm model, an acceptable specificity (80%) was achieved, whereas the sensitivity (60%) was far too low. In 2003, the EPISKIN Protocol was further refined by extension of the post-incubation period following chemical exposure. In the current study, we evaluated this EPISKIN refinement by applying it to EpiDerm. In addition, we developed technical improvements for the application of the Test chemicals and rinsing procedure, which reduced the variability of results and increased the percentage of correct predictions. A set of twenty non-coded reference substances from the ECVAM prevalidation study phase III (Fentem et al., 2001) was Tested with the final Protocol in three independent runs. Both high sensitivity (80%) and high specificity (78%) were achieved, and the statistical probability of correct classifications was high, so that the Test is now regarded ready for formal validation.
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optimisation of the epiderm Test Protocol for the upcoming ecvam validation study on in vitro skin irritation Tests
ALTEX-Alternatives to Animal Experimentation, 2004Co-Authors: Helena Kandarova, Ingrid Gerner, M Liebsch, E Genschow, Dieter Traue, B Slawik, Horst SpielmannAbstract:An ECVAM-funded prevalidation study (PV) was conducted during 1999 and 2000 to identify in vitro Tests capable of reliably distinguishing between skin irritants (I) and non-irritants (NI) according to European Union risk phrases ("R38" or no classification). The Tests evaluated were EpiDerm, EPISKIN, PREDISKIN, the non-perfused pig ear method, and the mouse skin integrity function Test (SIFT). Whereas reproducibility of the two human skin model Tests and SIFT was acceptable, none of the methods was deemed ready to enter a formal validation study due to their low predictivity. The ECVAM Skin Irritation Task Force therefore suggested improvements of Protocols and prediction models for these Tests. Furthermore, it was agreed that experience gained with the two human-skin models be shared, and a common Protocol should be developed for EpiDerm and EPISKIN (Zuang et al., 2002). When we applied an improved EPISKIN Protocol (Portes et al., 2002) to the EpiDerm model, an acceptable specificity (80%) was achieved, whereas the sensitivity (60%) was far too low. In 2003, the EPISKIN Protocol was further refined by extension of the post-incubation period following chemical exposure. In the current study, we evaluated this EPISKIN refinement by applying it to EpiDerm. In addition, we developed technical improvements for the application of the Test chemicals and rinsing procedure, which reduced the variability of results and increased the percentage of correct predictions. A set of twenty non-coded reference substances from the ECVAM prevalidation study phase III (Fentem et al., 2001) was Tested with the final Protocol in three independent runs. Both high sensitivity (80%) and high specificity (78%) were achieved, and the statistical probability of correct classifications was high, so that the Test is now regarded ready for formal validation.
Zissis Samaras - One of the best experts on this subject based on the ideXlab platform.
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fuel consumption and co2 emissions of passenger cars over the new worldwide harmonized Test Protocol
Applied Energy, 2016Co-Authors: Dimitris Tsokolis, Stefanos Tsiakmakis, Athanasios Dimaratos, Panayiotis Pistikopoulos, Biagio Ciuffo, Georgios Fontaras, Zissis SamarasAbstract:In 2014 the United Nations Economic Commission for Europe (UNECE) adopted the global technical regulation No. 15 concerning the Worldwide harmonized Light duty Test Procedure (WLTP). Having significantly contributed to its development, the European Commission is now aiming at introducing the new Test procedure in the European type-approval legislation for light duty vehicles in order to replace the New European Driving Cycle (NEDC) as the certification Test.
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fuel consumption and co2 emissions of passenger cars over the new worldwide harmonized Test Protocol
Applied Energy, 2016Co-Authors: Dimitris Tsokolis, Stefanos Tsiakmakis, Athanasios Dimaratos, Panayiotis Pistikopoulos, Biagio Ciuffo, Georgios Fontaras, Zissis SamarasAbstract:Abstract In 2014 the United Nations Economic Commission for Europe (UNECE) adopted the global technical regulation No. 15 concerning the Worldwide harmonized Light duty Test Procedure (WLTP). Having significantly contributed to its development, the European Commission is now aiming at introducing the new Test procedure in the European type-approval legislation for light duty vehicles in order to replace the New European Driving Cycle (NEDC) as the certification Test. The current paper aims to assess the effect of WLTP introduction on the reported CO 2 emissions from passenger cars presently measured under the New European Driving Cycle and the corresponding Test Protocol. The most important differences between the two Testing procedures, apart from the kinematic characteristics of the respective driving cycles, is the determination of the vehicle inertia and driving resistance, the gear shifting sequence, the soak and Test temperature and the post-Test charge balance correction applied to WLTP. In order to quantify and analyze the effect of these differences in the end value of CO 2 emissions, WLTP and NEDC CO 2 emission measurements were performed on 20 vehicles, covering almost the whole European market. WLTP CO 2 values range from 125.5 to 217.9 g/km, NEDC values range from 105.4 to 213.2 g/km and the ΔCO 2 between WLTP and NEDC ranges from 4.7 to 29.2 g/km for the given vehicle sample. The average cold start effect over WLTP was found 6.1 g/km, while for NEDC it was found 12.3 g/km. For a small gasoline and a medium sized diesel passenger car, the different inertia mass and driving resistance is responsible 63% and 81% of the observed ΔCO 2 between these two driving cycles respectively, whereas the other parameters (driving profile, gear shifting, Test temperature) account for the remaining 37% and 19%.
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fuel consumption and co2 emissions of passenger cars over the new worldwide harmonized Test Protocol
Applied Energy, 2016Co-Authors: Dimitris Tsokolis, Stefanos Tsiakmakis, Athanasios Dimaratos, Panayiotis Pistikopoulos, Biagio Ciuffo, Georgios Fontaras, Zissis SamarasAbstract:In 2014 the United Nations Economic Commission for Europe (UNECE) adopted the global technical regulation No. 15 concerning the Worldwide harmonized Light duty Test Procedure (WLTP). Having significantly contributed to its development, the European Commission is now aiming at introducing the new Test procedure in the European type-approval legislation for light duty vehicles in order to replace the New European Driving Cycle (NEDC) as the certification Test.
Biagio Ciuffo - One of the best experts on this subject based on the ideXlab platform.
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the development and validation of a vehicle simulator for the introduction of worldwide harmonized Test Protocol in the european light duty vehicle co2 certification process
Applied Energy, 2018Co-Authors: Georgios Fontaras, Stefanos Tsiakmakis, Victor Valverde, Vincenzo Arcidiacono, Konstantinos Anagnostopoulos, Dimitrios Komnos, Jelica Pavlovic, Biagio CiuffoAbstract:Abstract As of July 2017, the emissions type-approval of light-duty vehicles in Europe is based on the Worldwide Harmonized Light-duty vehicles Test Procedure (WLTP), introduced to replace the old and outdated New European Driving Cycle (NEDC) Test procedure. Since some elements of the European Legislation are still based on the NEDC (2020 CO2 emission targets, vehicle labelling, national vehicle taxation policies, etc.) in order to allow sufficient lead time to vehicle manufacturers and national authorities to adapt to the new procedure, a simulation-based approach was chosen to calculate CO2 emissions and fuel consumption according to the NEDC regime in the period 2017–2020. To achieve this objective without significantly increasing the cost and duration of the certification procedure, existing regulation foresees that vehicles are Tested over the WLTP for CO2 emissions, the Test results are used as input in a simulation model that then calculates the corresponding CO2 according to the NEDC Test Protocol. A dedicated vehicle simulation model (CO2MPAS) was developed for the purpose and is currently used for the type-approval of new vehicles in Europe. The development specifications of CO2MPAS were challenging, as it had to be highly accurate, exhibit fast operation, and function with a limited number of input data. This paper presents the development principles and process followed, details of the physical models employed in CO2MPAS, and provides information regarding its accuracy, validity and in use operation. CO2MPAS achieves low errors in the prediction of the NEDC cycle that in the controlled sample used for its development are of the order of 1% with a standard deviation of 3%, while the respective in-use numbers are of the order of 1.5% and 5%. In parallel, random sampling and Testing of a 10% of the type-approved vehicles also occurs in order to guarantee the quality of the CO2MPAS results and the validity of the process. It is concluded that CO2MPAS can be used to accurately estimate emissions of conventional vehicles within a ±4% accuracy range, even when limited input data are available. In addition, the in-use data analyzed suggest that the use of the tool enables the certification of about 2/3 of the new vehicle models without the need of additional experimental Tests. This is an important achievement as it reduces the costs and time necessary to certify light-duty vehicle CO2 emissions during the transitional period. Finally, it can be concluded that the use of CO2MPAS does not affect the declared CO2 emissions of vehicles over NEDC conditions.
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fuel consumption and co2 emissions of passenger cars over the new worldwide harmonized Test Protocol
Applied Energy, 2016Co-Authors: Dimitris Tsokolis, Stefanos Tsiakmakis, Athanasios Dimaratos, Panayiotis Pistikopoulos, Biagio Ciuffo, Georgios Fontaras, Zissis SamarasAbstract:In 2014 the United Nations Economic Commission for Europe (UNECE) adopted the global technical regulation No. 15 concerning the Worldwide harmonized Light duty Test Procedure (WLTP). Having significantly contributed to its development, the European Commission is now aiming at introducing the new Test procedure in the European type-approval legislation for light duty vehicles in order to replace the New European Driving Cycle (NEDC) as the certification Test.
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fuel consumption and co2 emissions of passenger cars over the new worldwide harmonized Test Protocol
Applied Energy, 2016Co-Authors: Dimitris Tsokolis, Stefanos Tsiakmakis, Athanasios Dimaratos, Panayiotis Pistikopoulos, Biagio Ciuffo, Georgios Fontaras, Zissis SamarasAbstract:Abstract In 2014 the United Nations Economic Commission for Europe (UNECE) adopted the global technical regulation No. 15 concerning the Worldwide harmonized Light duty Test Procedure (WLTP). Having significantly contributed to its development, the European Commission is now aiming at introducing the new Test procedure in the European type-approval legislation for light duty vehicles in order to replace the New European Driving Cycle (NEDC) as the certification Test. The current paper aims to assess the effect of WLTP introduction on the reported CO 2 emissions from passenger cars presently measured under the New European Driving Cycle and the corresponding Test Protocol. The most important differences between the two Testing procedures, apart from the kinematic characteristics of the respective driving cycles, is the determination of the vehicle inertia and driving resistance, the gear shifting sequence, the soak and Test temperature and the post-Test charge balance correction applied to WLTP. In order to quantify and analyze the effect of these differences in the end value of CO 2 emissions, WLTP and NEDC CO 2 emission measurements were performed on 20 vehicles, covering almost the whole European market. WLTP CO 2 values range from 125.5 to 217.9 g/km, NEDC values range from 105.4 to 213.2 g/km and the ΔCO 2 between WLTP and NEDC ranges from 4.7 to 29.2 g/km for the given vehicle sample. The average cold start effect over WLTP was found 6.1 g/km, while for NEDC it was found 12.3 g/km. For a small gasoline and a medium sized diesel passenger car, the different inertia mass and driving resistance is responsible 63% and 81% of the observed ΔCO 2 between these two driving cycles respectively, whereas the other parameters (driving profile, gear shifting, Test temperature) account for the remaining 37% and 19%.
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fuel consumption and co2 emissions of passenger cars over the new worldwide harmonized Test Protocol
Applied Energy, 2016Co-Authors: Dimitris Tsokolis, Stefanos Tsiakmakis, Athanasios Dimaratos, Panayiotis Pistikopoulos, Biagio Ciuffo, Georgios Fontaras, Zissis SamarasAbstract:In 2014 the United Nations Economic Commission for Europe (UNECE) adopted the global technical regulation No. 15 concerning the Worldwide harmonized Light duty Test Procedure (WLTP). Having significantly contributed to its development, the European Commission is now aiming at introducing the new Test procedure in the European type-approval legislation for light duty vehicles in order to replace the New European Driving Cycle (NEDC) as the certification Test.
Stephan Gielen - One of the best experts on this subject based on the ideXlab platform.
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validation of a brief step Test Protocol for estimation of peak oxygen uptake
European Journal of Preventive Cardiology, 2015Co-Authors: Frank Beutner, Romy Ubrich, Silke Zachariae, Christoph Engel, Marcus Sandri, Andrej Teren, Stephan GielenAbstract:BackgroundPhysical exercise capacity has been shown to predict cardiovascular disease incidence and is increasingly measured in epidemiological studies. However, direct measurement of peak oxygen uptake is too time consuming in large-scale studies. We therefore investigated whether a brief 3-minute step-Test Protocol can be used to estimate peak oxygen uptake in these settings.Design and methodsA group of 97 subjects performed the YMCA step Test and a maximal treadmill Test with continuous measurement of oxygen uptake. Correlation and linear regression analyses were used to identify VO2peak predictors obtained from the step Test and to develop models for VO2peak estimation.ResultsThe YMCA model, including the 1-minute heart beat count, predicted VO2peak with R = 0.83. A novel simplified model based on the heart rate at 45 s of recovery performed comparable (R = 0.83). However, models based on heart rate measures were only valid in subjects who completed the Test according to Protocol, but not in subjects ...
Frances Wallach - One of the best experts on this subject based on the ideXlab platform.
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toward a Test Protocol for surface decontamination using a mobile whole room uvgi device
Photochemistry and Photobiology, 2021Co-Authors: Richard L Vincent, Stephen N Rudnick, James J Mcdevitt, Frances WallachAbstract:Mobile whole-room UVGI devices are used in healthcare settings to control surface-borne pathogens. Unfortunately, no standard method comparing the efficacy of these devices is available. We accessed the effect of shadows on UVC-254 nm inactivation. The evaluation of a mobile whole-room UVGI device, used spores of B. atrophaeus as a surrogate for C. difficile and S. aureus as a surrogate for MSRA. Inactivation after 10 minutes of exposure varied significantly depending on whether the spores received direct UV exposure (4.3 log reduction), both direct and reflected UV exposure (3.0 to 4.0 log reduction) or reflected UV exposure alone (<1.0 log reduction). The susceptibility (z-value) for inactivation of B. atrophaeus spores on a glass surface was estimated to be 0.00312 m2 /J. S. aureus microbial log reductions were approximately 5.5 for direct UV exposure, 3.6 to 5.2 for both direct and reflected UV exposure, and approximately 2.75 for only reflected UV exposure. Our measurement of reflected dose ranged from 0.46% to 1.47%. Based our findings, B. atrophaeus spores should be considered as a model organism for Testing the impact of shadows on mobile whole-room UVGI device inactivation. Optimizing the reflected component of whole-room UVGI is important, especially for UVC resistant organisms.
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toward a Test Protocol for surface decontamination using a mobile whole room uvgi device
Photochemistry and Photobiology, 2021Co-Authors: Richard L Vincent, Stephen N Rudnick, James J Mcdevitt, Frances WallachAbstract:Mobile whole-room UVGI devices are used in healthcare settings to control surface-borne pathogens. Unfortunately, no standard method comparing the efficacy of these devices is available. We accessed the effect of shadows on UVC 254 nm inactivation. The evaluation of a mobile whole-room UVGI device used spores of Bacillus atrophaeus as a surrogate for Clostridium difficile and Staphylococcus aureus as a surrogate for MSRA. Inactivation after 10 min of exposure varied significantly depending on whether the spores received direct UV exposure (4.3 log reduction), both direct and reflected UV exposure (3.0-4.0 log reduction) or reflected UV exposure alone (<1.0 log reduction). The susceptibility (z-value) for inactivation of B. atrophaeus spores on a glass surface was estimated to be 0.00312 m2 J-1 . Staphylococcus aureus microbial log reductions were approximately 5.5 for direct UV exposure, 3.6-5.2 for both direct and reflected UV exposure and approximately 2.75 for only reflected UV exposure. Our measurement of reflected dose ranged from 0.46% to 1.47%. Based on our findings, B. atrophaeus spores should be considered as a model organism for Testing the impact of shadows on mobile whole-room UVGI device inactivation. Optimizing the reflected component of whole-room UVGI is important, especially for UVC-resistant organisms.
