Data Compression Approach for Long-Term Monitoring of Pavement Structures

Pavement structures are designed to withstand continuous damage during their design life. Damage starts as soon as the pavement is open to traffic and increases with time. If maintenance activities are not considered in the initial design or considered but not applied during the service life, damage will grow to a point where rehabilitation may be the only and most expensive option left. In order to monitor the evolution of damage and its severity in pavement structures, a novel data compression approach based on cumulative measurements from a piezoelectric sensor is presented in this paper. Specifically, the piezoelectric sensor uses a thin film of polyvinylidene fluoride to sense the energy produced by the micro deformation generated due to the application of traffic loads. Epoxy solution has been used to encapsulate the membrane providing hardness and flexibility to withstand the high-loads and the high-temperatures during construction of the asphalt layer. The piezoelectric sensors have been exposed to three months of loading (approximately 1.0 million loads of 65 kN) at the French Institute of Science and Technology for Transport, Development and Networks (IFSTTAR) fatigue carrousel. Notably, the sensors survived the construction and testing. Reference measurements were made with a commercial conventional strain gauge specifically designed for measurements in hot mix asphalt layers. Results from the carrousel successfully demonstrate that the novel approach can be considered as a good indicator of damage progression, thus alleviating the need to measure strains in pavement for the purpose of damage tracking

Assessment of cracks detection in pavement by a distributed fiber optic sensing technology

International audienceThis paper presents the feasibility of damage detection in asphalt pavements by embedded fiber optics as a new non-destructive inspection technique. The distributed fiber optic sensing technology based on the Rayleigh scattering was used in this study. The main advantage of this technique is that it allows to measure strains over a long length of fiber optic with a high spatial resolution, less than 1 cm. By comparing strain profiles measured at different times, an attempt was made to link strain changes with the appearance of damage (cracking) in the pavement. This non-destructive method was evaluated on accelerated pavement testing facility, in a bituminous pavement. In our experimentation, the optical fibers were placed near the bottom of the asphalt layer. The application of 728 000 heavy vehicle loads (65 kN dual wheel loads) was simulated in the experiment. Optical fiber measurements were made at regular intervals and surface cracking of the pavement was surveyed. After some traffic, a significant increase of strains was detected by the optical fibers at different points in the pavement structure, before any damage was visible. Later, cracking developed in the zones where the strain profiles were modified, X. Chapeleau et al. thus indicating a clear relationship between the increased strains and crack initiation. These first tests demonstrate that distributed fiber optic sensors based on Rayleigh scattering can be used to detect crack initiation and propagation in pavements, by monitoring strain profiles in the bituminous layers

BioRePavation - Innovation In Bio-Recycling

The main scientific and technical objectives of the BioRePavation project have been to prove that alternative binders can be used to recycle asphaltic pavement with the same level of performance as conventional solutions with petroleum bitumen. To do so, the consortium proposed to build a demonstration where three innovative pavement solutions using bio-materials were tested using an accelerated pavement testing facility (IFSTTAR fatigue carousel): - A bio-based additive from pine chemistry designed to Increase RA content to 70%, even 100% in theory - A Bio-based additive designed to increase compatibility between fresh bitumen and RA: Epoxidized Methyl Soyate - A Biobitumen designed for full replacement of fresh bitumen The survey of performance was performed by both measuring the traffic level needed for the pavement solution to reach a distress mechanism and investigating the binder physicochemical evolution using an innovative non-destructive method. BioRePavation also assessed the environmental impacts of the combined use of bio-binders and high-content of RA in asphalt mixes. Special attention was given to airborne emissions that were directly measured in the laboratory. Obtained data were used to perform a risk assessment, as well as a Life Cycle Assessment (LCA) for the aforementioned BioRePavation technologies. Finally, the proof of concept was demonstrated: the innovative pavement mixes assessed in the BioRePavation international project behave better than a conventional reference mix. They now provide durable solutions, assessed by a full scale accelerated test and an environmental analysis, to build roads using high rate recycling and involving biomaterials as additive or alternative to bitumen.This proceeding is published as Pouget, S.; Chailleux, E.; Porot, L.; Williams, R.C.; Planche, J.P.; Lo Presti, D.; Blanc, J.; Hornych, P.; Del Barco Carrion, A.J.; and Gaudefroy, V. “BioRePavation - Innovation In Bio-Recycling”, 7th Eurasphalt & Eurobitume Congress- Asphalt 4.0 for future mobility, Madrid, Spain (Virtual), June 2021. Copyright 2021, European Asphalt Pavement Association and the European Bitumen Association. Posted with permission

From Laboratory Mixes to Full Scale Test: Rutting Evaluation of Bio-recycled Asphalt Mixes

The present paper describes the rutting behavior of innovative mixes in-corporating 50% of Reclaimed Asphalt (RA) with bio-materials. They were assessed in the laboratory and in a full-scale accelerated experiment. The innovative mixes studied here contain bio-materials especially designed to help recycling by re-activating the aged binder in RA. Four mixes were evaluated: three of them are manufactured with bio-materials, (two bio-rejuvenators and one bio-binder) and one is a control mix, which is a high modulus asphalt mix (EME2). In this study, the rutting resistance of the four mixes was first evaluated in the laboratory with both European and US methods. The full-scale test was then performed in order to evaluate the rutting resistance of the bio-recycled asphalt mixes under heavy traffic (200 000 load cycles loaded at 65 kN) and compare it with the control. A simplified analysis leads to the conclusion that, with the Nantes climate, a daily traffic of 150 heavy vehicles per day applied for 20 years corresponds to approximately 200 000 heavy vehicle loads applied when the surface temperature exceeds 30°C. Therefore, it can be considered that the rutting evaluation made on the carrousel represents almost 20 years of traffic during hot periods. The results obtained on the test track are consistent with the laboratory rutting tests showing good performance of all the mixes. The materials presenting the best performance on the test track also presented the best performance in the laboratory.This is a manuscript of a proceeding published as Juliette Blanc, Emmanuel Chailleux, Pierre Hornych, Chris Williams, Zahra Sotoodeh-Nia, et al. (2022). From laboratory mixes to full scale test: rutting evaluation of bio-recycled asphalt mixes. RILEM International Symposium on Bituminous Materials. ISBM 2020, Dec 2020, Lyon, France. pp.951-957, 10.1007/978-3-030-46455-4_121. hal-04376794. Manuscript is distributed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License. © The Author(s), under exclusive license to Springer Nature Switzerland AG 202

J Clin Invest

Arterial cardiovascular events are the leading cause of death in patients with JAK2V617F myeloproliferative neoplasms (MPN). However, their mechanisms are poorly understood. The high prevalence of myocardial infarction without significant coronary stenosis or atherosclerosis in patients with MPN suggests that vascular function is altered. Consequences of JAK2V617F mutation on vascular reactivity are unknown. We observe here increased responses to vasoconstrictors in arteries from Jak2V617F mice, resulting from disturbed endothelial nitric oxide pathway and increased endothelial oxidative stress. This response was reproduced in wild-type mice by circulating microvesicles isolated from patients carrying JAK2V617F and by erythrocyte-derived microvesicles from transgenic mice. Microvesicles of other cellular origins had no effect. This effect was observed ex vivo on isolated aortas, but also in vivo on femoral arteries. Proteomic analysis of microvesicles derived from JAK2V617F erythrocytes identified increased expression of myeloperoxidase as the likely mechanism accounting for microvesicles effect. Myeloperoxidase inhibition in microvesicles derived from JAK2V617F erythrocytes supressed their effect on oxidative stress. Antioxidants, such as simvastatin and N-acetyl-cysteine, improved arterial dysfunction in Jak2V617F mice. In conclusion, JAK2V617F MPN are characterized by exacerbated vasoconstrictor responses resulting from increased endothelial oxidative stress caused by circulating erythrocyte-derived microvesicles. Simvastatin appears as promising therapeutic strategy in this setting

La sculpture romaine en Occident

Cet ouvrage réunit les résultats de deux manifestations complémentaires  : d’une part, la table ronde intitulée «  Rendre à César  », organisée le mercredi 20 juin 2012, à Paris, au Musée du Louvre et, d’autre part, les «  Rencontres autour de la sculpture romaine conservée en France  » qui ont eu lieu du 18 au 20 octobre 2012 au Musée départemental Arles antique. La richesse des interventions lors de ces deux manifestations permet de restituer un ouvrage composé de trente-huit articles, répartis en trois parties et une conclusion. La première partie, en écho et en développement de la table ronde du Louvre, porte sur le portrait du «  César du Rhône  », aussi bien que sur «  Le portrait romain en Gaule  ». La deuxième partie publie cinq études autour des «  nouvelles techniques d’investigations scientifiques  » et présente l’analyse des matériaux des sculptures en pierre et en bronze, découvertes dans le Rhône à Arles, ainsi qu’une étude ethnoarchéologique sur les techniques de production du portrait. Enfin une troisième partie présente les «  découvertes récentes et les nouvelles recherches  », déclinées en seize études qui sont consacrées à des études de cas (Autun, Vaison-la-Romaine, Nîmes, Metz-Divodurum, Apt), ainsi qu’à des relectures novatrices de sculptures méconnues (Plouarzel, Langres, Avignonet-Lauragais, Vernègues, vallée de l’Ubaye, Besançon, Lyon). Robert Turcan signe la conclusion. Ainsi, «  La sculpture romaine en Occident. Nouveaux regards   » reflète la variété et l’intérêt des questionnements actuels dans ce domaine

Extracorporeal Membrane Oxygenation for Severe Acute Respiratory Distress Syndrome associated with COVID-19: An Emulated Target Trial Analysis.

RATIONALE: Whether COVID patients may benefit from extracorporeal membrane oxygenation (ECMO) compared with conventional invasive mechanical ventilation (IMV) remains unknown. OBJECTIVES: To estimate the effect of ECMO on 90-Day mortality vs IMV only Methods: Among 4,244 critically ill adult patients with COVID-19 included in a multicenter cohort study, we emulated a target trial comparing the treatment strategies of initiating ECMO vs. no ECMO within 7 days of IMV in patients with severe acute respiratory distress syndrome (PaO2/FiO2 <80 or PaCO2 ≥60 mmHg). We controlled for confounding using a multivariable Cox model based on predefined variables. MAIN RESULTS: 1,235 patients met the full eligibility criteria for the emulated trial, among whom 164 patients initiated ECMO. The ECMO strategy had a higher survival probability at Day-7 from the onset of eligibility criteria (87% vs 83%, risk difference: 4%, 95% CI 0;9%) which decreased during follow-up (survival at Day-90: 63% vs 65%, risk difference: -2%, 95% CI -10;5%). However, ECMO was associated with higher survival when performed in high-volume ECMO centers or in regions where a specific ECMO network organization was set up to handle high demand, and when initiated within the first 4 days of MV and in profoundly hypoxemic patients. CONCLUSIONS: In an emulated trial based on a nationwide COVID-19 cohort, we found differential survival over time of an ECMO compared with a no-ECMO strategy. However, ECMO was consistently associated with better outcomes when performed in high-volume centers and in regions with ECMO capacities specifically organized to handle high demand. This article is open access and distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives License 4.0 (http://creativecommons.org/licenses/by-nc-nd/4.0/)