889 research outputs found

    The DICE calibration project: design, characterization, and first results

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    We describe the design, operation, and first results of a photometric calibration project, called DICE (Direct Illumination Calibration Experiment), aiming at achieving precise instrumental calibration of optical telescopes. The heart of DICE is an illumination device composed of 24 narrow-spectrum, high-intensity, light-emitting diodes (LED) chosen to cover the ultraviolet-to-near-infrared spectral range. It implements a point-like source placed at a finite distance from the telescope entrance pupil, yielding a flat field illumination that covers the entire field of view of the imager. The purpose of this system is to perform a lightweight routine monitoring of the imager passbands with a precision better than 5 per-mil on the relative passband normalisations and about 3{\AA} on the filter cutoff positions. The light source is calibrated on a spectrophotometric bench. As our fundamental metrology standard, we use a photodiode calibrated at NIST. The radiant intensity of each beam is mapped, and spectra are measured for each LED. All measurements are conducted at temperatures ranging from 0{\deg}C to 25{\deg}C in order to study the temperature dependence of the system. The photometric and spectroscopic measurements are combined into a model that predicts the spectral intensity of the source as a function of temperature. We find that the calibration beams are stable at the 10410^{-4} level -- after taking the slight temperature dependence of the LED emission properties into account. We show that the spectral intensity of the source can be characterised with a precision of 3{\AA} in wavelength. In flux, we reach an accuracy of about 0.2-0.5% depending on how we understand the off-diagonal terms of the error budget affecting the calibration of the NIST photodiode. With a routine 60-mn calibration program, the apparatus is able to constrain the passbands at the targeted precision levels.Comment: 25 pages, 27 figures, accepted for publication in A&

    Minimal residual disease after transplantation or lenalidomide-based consolidation in myeloma patients: a prospective analysis

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    We analyzed 50 patients who achieved at least a very good partial response in the RV-MM-EMN-441 study. Patients received consolidation with autologous stem-cell transplantation (ASCT) or cyclophosphamide-lenalidomide-dexamethasone (CRD), followed by Lenalidomide-based maintenance. We assessed minimal residual disease (MRD) by multi-parameter flow cytometry (MFC) and allelic-specific oligonucleotide real-time quantitative polymerase chain reaction (ASO-RQ-PCR) after consolidation, after 3 and 6 courses of maintenance, and thereafter every 6 months until progression. By MFC analysis, 19/50 patients achieved complete response (CR) after consolidation, and 7 additional patients during maintenance. A molecular marker was identified in 25/50 patients, 4/25 achieved molecular-CR after consolidation, and 3 additional patients during maintenance. A lower MRD value by MFC was found in ASCT patients compared with CRD patients (p = 0.0134). Tumor burden reduction was different in patients with high-risk vs standard-risk cytogenetics (3.4 vs 5.2, ln-MFC; 3 vs 6 ln-PCR, respectively) and in patients who relapsed vs those who did not (4 vs 5, ln-MFC; 4.4 vs 7.8 ln-PCR). MRD progression anticipated clinical relapse by a median of 9 months while biochemical relapse by a median of 4 months. MRD allows the identification of a low-risk group, independently of response, and a better characterization of the activity of treatments

    Biclustering models for two-mode ordinal data

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    The work in this paper introduces finite mixture models that can be used to simul- taneously cluster the rows and columns of two-mode ordinal categorical response data, such as those resulting from Likert scale responses. We use the popular proportional odds parameterisation and propose models which provide insights into major patterns in the data. Model-fitting is performed using the EM algorithm and a fuzzy allocation of rows and columns to corresponding clusters is obtained. The clustering ability of the models is evaluated in a simulation study and demonstrated using two real data sets

    Comparison of the influence of cyclosporine and tacrolimus on the pharmacokinetics of prednisolone in adult male kidney transplant recipients

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    Cyclosporine has been observed to precipitate cushingoid features in kidney transplant recipients already on prednisolone. Some pharmacokinetic studies have demonstrated increased prednisolone exposure in patients on cyclosporine therapy compared with azathioprine, whereas other studies have found no difference. The objective of this study was to determine whether cyclosporine impacts on prednisolone exposure as compared with tacrolimus

    Discovering Argumentative Patterns in Energy Polylogues: A Macroscope for Argument Mining

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    A macroscope is proposed and tested here for the discovery of the unique argumentative footprint that characterizes how a collective (e.g., group, online community) manages differences and pursues disagreement through argument in a polylogue. The macroscope addresses broader analytic problems posed by various conceptualizations of large-scale argument, such as fields, spheres, communities, and institutions. The design incorporates a two-tier methodology for detecting argument patterns of the arguments performed in arguing by an interactive collective that produces views, or topographies, of the ways that issues are generated in the making and defending of standpoints. The design premises for the macroscope build on insights about argument patterns from pragma-dialectical theory by incorporating research and theory on disagreement management and the Argumentum Model of Topics. The design reconceptualizes prototypical and stereotypical argument patterns for characterizing large-scale argumentation. A prototype of the macroscope is tested on data drawn from six threads about oil-drilling and fracking from the subreddit Changemyview. The implementation suggests the efficacy of the macroscope’s design and potential for identifying what communities make controversial and how the disagreement space in a polylogue is managed through stereotypical argument patterns in terms of claims/premises, inferential relations, and presentational devices

    The Butterfly Fauna Of The Italian Maritime Alps:Results Of The «Edit» Project

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    Bonelli, Simona, Barbero, Francesca, Casacci, Luca Pietro, Cerrato, Cristiana, Balletto, Emilio (2015): The butterfly fauna of the Italian Maritime Alps: results of the EDIT project. Zoosystema 37 (1): 139-167, DOI: 10.5252/z2015n1a6, URL: http://dx.doi.org/10.5252/z2015n1a

    Modelling vehicles acceleration during overtaking manoeuvres

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    [EN] Abstract: Overtaking manoeuvre is a key issue for two-lane rural roads. These roads should provide sufficient overtaking sight distance (OSD) at certain locations to allow faster vehicles to pass slower ones. However, overtaking requires occupying the opposing lane, which represents a serious safety concern. Severity of overtaking related crashes is very high, compared with other manoeuvres. The development of advanced driver assistance systems (ADAS) for overtaking is being a complex task. Only few systems have been developed, but are not still in use. This research incorporated accurate data of real manoeuvres to improve the knowledge of the phenomenon. The trajectory of the overtaking vehicles on the left lane was observed. An instrumented vehicle measured the overtaking time and distance, the abreast position, and the initial and final speed of 180 drivers that passed it during a field experiment. Six different kinematic models (such as uniform acceleration or linear variation of acceleration) were calibrated. Generally, drivers started to accelerate before changing to the opposing lane. These models may be applied to ADAS, to estimate OSD and to improve microsimulation models.Part of this research was included in the project 'Desarrollo de modelos de distancias de visibilidad de adelantamiento', with reference code TRA2010-21736 and subsidised by the Spanish Ministery of Economy and Competitivity. The authors also thank Prof Dr Sayed, from University of British Columbia, for his valuable review.Llorca Garcia, C.; Moreno, AT.; García García, A. (2016). Modelling vehicles acceleration during overtaking manoeuvres. IET Intelligent Transport Systems. 10(3):206-215. https://doi.org/10.1049/iet-its.2015.0035S206215103Gray, R., & Regan, D. M. (2005). Perceptual Processes Used by Drivers During Overtaking in a Driving Simulator. Human Factors: The Journal of the Human Factors and Ergonomics Society, 47(2), 394-417. doi:10.1518/0018720054679443Basilio, N., Morice, A. H. P., Marti, G., & Montagne, G. (2015). High- and Low-Order Overtaking-Ability Affordances. Human Factors: The Journal of the Human Factors and Ergonomics Society, 57(5), 879-894. doi:10.1177/0018720815583581Morice, A. H. P., Diaz, G. J., Fajen, B. R., Basilio, N., & Montagne, G. (2015). An Affordance-Based Approach to Visually Guided Overtaking. Ecological Psychology, 27(1), 1-25. doi:10.1080/10407413.2015.991641Farah, H., Bekhor, S., & Polus, A. (2009). Risk evaluation by modeling of passing behavior on two-lane rural highways. Accident Analysis & Prevention, 41(4), 887-894. doi:10.1016/j.aap.2009.05.006Hassan, Y., Easa, S. M., & El Halim, A. O. A. (1996). Passing sight distance on two-lane highways: Review and revision. Transportation Research Part A: Policy and Practice, 30(6), 453-467. doi:10.1016/0965-8564(95)00032-1Wang, Y., & Cartmell, M. P. (1998). New Model for Passing Sight Distance on Two-Lane Highways. Journal of Transportation Engineering, 124(6), 536-545. doi:10.1061/(asce)0733-947x(1998)124:6(536)Sparks, G. A., Neudorf, R. D., Robinson, J. B. L., & Good, D. (1993). Effect of Vehicle Length on Passing Operations. Journal of Transportation Engineering, 119(2), 272-283. doi:10.1061/(asce)0733-947x(1993)119:2(272)Hanley, P. F., & Forkenbrock, D. J. (2005). Safety of passing longer combination vehicles on two-lane highways. Transportation Research Part A: Policy and Practice, 39(1), 1-15. doi:10.1016/j.tra.2004.09.001Khoury, J. E., & Hobeika, A. G. (2012). Integrated Stochastic Approach for Risk and Service Estimation: Passing Sight Distance Application. Journal of Transportation Engineering, 138(5), 571-579. doi:10.1061/(asce)te.1943-5436.0000366Jenkins, J. M., & Rilett, L. R. (2004). Application of Distributed Traffic Simulation for Passing Behavior Study. Transportation Research Record: Journal of the Transportation Research Board, 1899(1), 11-18. doi:10.3141/1899-02Rakha, H., Ahn, K., & Trani, A. (2004). Development of VT-Micro model for estimating hot stabilized light duty vehicle and truck emissions. Transportation Research Part D: Transport and Environment, 9(1), 49-74. doi:10.1016/s1361-9209(03)00054-3Polus, A., Livneh, M., & Frischer, B. (2000). Evaluation of the Passing Process on Two-Lane Rural Highways. Transportation Research Record: Journal of the Transportation Research Board, 1701(1), 53-60. doi:10.3141/1701-07Harwood, D. W., Gilmore, D. K., & Richard, K. R. (2010). Criteria for Passing Sight Distance for Roadway Design and Marking. Transportation Research Record: Journal of the Transportation Research Board, 2195(1), 36-46. doi:10.3141/2195-05Hegeman, G., Tapani, A., & Hoogendoorn, S. (2009). Overtaking assistant assessment using traffic simulation. Transportation Research Part C: Emerging Technologies, 17(6), 617-630. doi:10.1016/j.trc.2009.04.010Milanés, V., Llorca, D. F., Villagrá, J., Pérez, J., Fernández, C., Parra, I., … Sotelo, M. A. (2012). Intelligent automatic overtaking system using vision for vehicle detection. Expert Systems with Applications, 39(3), 3362-3373. doi:10.1016/j.eswa.2011.09.024Isermann, R., Mannale, R., & Schmitt, K. (2012). Collision-avoidance systems PRORETA: Situation analysis and intervention control. Control Engineering Practice, 20(11), 1236-1246. doi:10.1016/j.conengprac.2012.06.003Petrov, P., & Nashashibi, F. (2014). Modeling and Nonlinear Adaptive Control for Autonomous Vehicle Overtaking. IEEE Transactions on Intelligent Transportation Systems, 15(4), 1643-1656. doi:10.1109/tits.2014.2303995Llorca, C., & García, A. (2011). Evaluation of Passing Process on Two-Lane Rural Highways in Spain with New Methodology Based on Video Data. Transportation Research Record: Journal of the Transportation Research Board, 2262(1), 42-51. doi:10.3141/2262-05Llorca, C., Moreno, A. T., García, A., & Pérez-Zuriaga, A. M. (2013). Daytime and Nighttime Passing Maneuvers on a Two-Lane Rural Road in Spain. Transportation Research Record: Journal of the Transportation Research Board, 2358(1), 3-11. doi:10.3141/2358-01Llorca, C., Moreno, A. T., Pérez-Zuriaga, A. M., & García, A. (2013). Influence of age, gender and delay on overtaking dynamics. IET Intelligent Transport Systems, 7(2), 174-181. doi:10.1049/iet-its.2012.0147Khoury, J. E., & Hobeika, A. (2007). Incorporating Uncertainty into the Estimation of the Passing Sight Distance Requirements. Computer-Aided Civil and Infrastructure Engineering, 22(5), 347-357. doi:10.1111/j.1467-8667.2007.00491.xRakha, H., Snare, M., & Dion, F. (2004). Vehicle Dynamics Model for Estimating Maximum Light-Duty Vehicle Acceleration Levels. Transportation Research Record: Journal of the Transportation Research Board, 1883(1), 40-49. doi:10.3141/1883-05Fitzpatrick, K., Chrysler, S. T., & Brewer, M. (2012). Deceleration Lengths for Exit Terminals. Journal of Transportation Engineering, 138(6), 768-775. doi:10.1061/(asce)te.1943-5436.000038

    Euclid preparation. III. Galaxy cluster detection in the wide photometric survey, performance and algorithm selection

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    Galaxy cluster counts in bins of mass and redshift have been shown to be a competitive probe to test cosmological models. This method requires an efficient blind detection of clusters from surveys with a well-known selection function and robust mass estimates, which is particularly challenging at high redshift. The Euclid wide survey will cover 15 000 deg2 of the sky, avoiding contamination by light from our Galaxy and our solar system in the optical and near-infrared bands, down to magnitude 24 in the H-band. The resulting data will make it possible to detect a large number of galaxy clusters spanning a wide-range of masses up to redshift ∼2 and possibly higher. This paper presents the final results of the Euclid Cluster Finder Challenge (CFC), fourth in a series of similar challenges. The objective of these challenges was to select the cluster detection algorithms that best meet the requirements of the Euclid mission. The final CFC included six independent detection algorithms, based on different techniques, such as photometric redshift tomography, optimal filtering, hierarchical approach, wavelet and friend-of-friends algorithms. These algorithms were blindly applied to a mock galaxy catalog with representative Euclid-like properties. The relative performance of the algorithms was assessed by matching the resulting detections to known clusters in the simulations down to masses of M₂₀₀ ∼ 10^(13.25) M⊙. Several matching procedures were tested, thus making it possible to estimate the associated systematic effects on completeness to 80% completeness for a mean purity of 80% down to masses of 10¹⁴ M⊙ and up to redshift z = 2. Based on these results, two algorithms were selected to be implemented in the Euclid pipeline, the Adaptive Matched Identifier of Clustered Objects (AMICO) code, based on matched filtering, and the PZWav code, based on an adaptive wavelet approach
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