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Terpenes, natural dyes and photochemistry: toward the synthesis of photoactive bio-based materials with biocide properties
No full textInternational audienceCombining bioresources and photo-induced polymerization is a promising way to design sustainable and high-performing antibacterial materials. In this study, we propose a green synthesis of bio-based materials with dual antibacterial properties by photopolymerization. Two new methacrylate-based hydroxyanthraquinones derived from purpurin and alizarin (P-3Ac and Al-2Ac) have been designed to promote the polymerization of bio-based vegetable oil and terpene blend mixtures under visible-light irradiation up to 470 nm. All the photochemical mechanisms involved in the photopolymerization processes have been described by steady state photolysis, electron spin resonance spin-trapping (ESR ST) and real-time Fourier transform infrared (RT-FTIR) spectroscopy. Interestingly, the photo-initiating properties of P-3Ac and Al-2Ac are greatly enhanced in comparison with the native unmodified purpurin and alizarin. Polymerization of soybean oil acrylate and linalool through a thiol–ene process has led to the formation of photoactive bio-based materials able to generate biocide reactive oxygen species (ROS) upon light exposure which can also be used as contact-killing materials for tremendous inhibition of bacterial growth. The respective effects of each biocide agent (ROS and linalool) were compared and combined, highlighting stunning inhibition properties of the materials (higher than 99.99%) against both E. coli (Gram negative) and S. aureus (Gram positive), even after a second antibacterial recycling test. Prior to photo-printing experiments, rheological studies have been performed to design greener 3D-photoinduced materials. According to the high bio-renewable carbon contents of the photosensitive P-3Ac-based formulation and its great processability, 3D objects have been designed using Digital Light Processing (DLP) technology upon 405 nm light emitting diode exposure
Multifractal analysis of wind turbine power and rainfall from an operational wind farm -Part 2: Joint analysis of available wind power and rain intensity
No full textInternational audienceIn the increasing global transition towards renewable and carbon-neutral energy, understanding the uncertainties associated with wind power production is extremely important. In addition to the widely acknowledged uncertainties from turbulence and wind intermittency, further complexity arises from the influence of rainfall, which only a limited number of studies have addressed so far. To understand this, multiple 3D sonic anemometers, mini meteorological stations, and optical disdrometers were employed on a meteorological mast on the Pays d'Othe wind farm (110 km south-east of Paris, France) in the framework of the Rainfall Wind Turbine or Turbulence (RW-Turb) project (https://hmco.enpc.fr/portfolio-archive/rw-turb/, last access: 26 November 2024). With these simultaneously measured data, wind power and its associated atmospheric fields were studied under various rainy conditions.Variations of the wind velocity, power available on the wind farm, power produced by wind turbines, and air density are examined here, under rainy and dry conditions, using the scale-invariant framework of universal multifractals (UM). Since rated power acts like an upper threshold in statistical analysis of turbine power (discussed in Part 1), theoretically available power was used as a proxy. From an event-based analysis, differences in UM parameters were observed between rainy and dry conditions for the fields. This is explored further using joint multifractal analysis, which revealed an increase in the correlation exponent between various fields with the rain rate. Here we also examine the possibility of variation in power production by rainy conditions (convective or stratiform) as well as by regimes of wind velocity. While examining time steps according to wind velocity, turbine power curves showed different regions of departure from the state curve according to the rain rate.</p
Improve the projection of East China summer precipitation with emergent constraints
No full textInternational audienceUnder global warming, summer precipitation over East China was projected to increase by current state-of-the-art climate models, but a large inter-model spread exists. Here we try to reduce the projection uncertainty by imposing constraints. Our procedure consists of first decomposing the projected future precipitation into inter-model principal components. The two leading modes (region-wide uniform monopole and north-south dipole, accounting for 55% of variability), by emergent constraints, are then linked to the simulation of historical precipitation in the northwest Pacific and the tropical Pacific (constraining areas). This allows us to reduce the uncertainties by 23% and obtain a smaller increase of projected precipitation in East China, relative to previous multi-model ensemble projections. Quasi-uniform increases, although weak, are obtained for the first mode, while the second mode shows a contrast pattern with a decrease in the south and an increase in the north, which both contribute to the spatial structure of constrainted projection. It is also shown that the emergent relations of both modes are physically consistent, with an enhancement of future zonal land-sea thermal contrast and a La Niña-like pattern, respectively. The use of emergent constraints inspires more confidence in the future regional precipitation projection and helps policymakers and stakeholders adjust their management policies
The effect of patients' socioeconomic status in rehabilitation centers on the efficiency and performance
No full textInternational audienceBACKGROUND: Patients’ socioeconomic status on hospitals’ efficiency in controlling for clinical component characteristics may have a role that has few been studied in rehabilitation centers.DESIGN: Because of the national health insurance system, rehabilitation centers are free of charge. To answer whether a patient’s socioeconomic status (SES) is associated with efficiency and performance, we use a counterfactual analysis to get the patient’s SES effect “as if” the patient’s case was identical to whatever hospital. We restrained the data to patients from public acute care units where the decision on rehabilitation sector admission is based on availability, limiting bias by confounding factors. Besides, an analysis of six pathologies led to the same results.SETTING: An exhaustive, detailed administrative database on rehabilitation center stays in France. To define the patients’ socioeconomic status, we use two sources of data: the information collected at the time of the patient’s entry into rehabilitation care and the information collected during the patient’s stay in acute care. This double information avoids possible loss of socio-economic details between the two admissions.POPULATION: Patients recruited were exhaustively admitted over the year 2018 for stroke, chronic obstructive pulmonary disease, heart failure, or total hip replacement in France in the acute care unit and then in a rehab center. Mainly the elderly population. Information on patients’ demography, comorbidities, and SES are coded due to the reimbursement system. Different dimensions controlling for factors (hospital ownership, patient clinical characteristics, rehabilitation care specificities, medical staff detailed information, and patients’ socioeconomic status), were progressively added to control for any differences in baseline data between the two groups.METHODS: We assess rehabilitation centers’ efficiency by combining selected outcome quality indicators (Physical score improvement, Cognitive score improvement, Mortality, Return-to-home). The specific Providers’ Activity Index is used to get the performance index.CONCLUSIONS: The performance of healthcare institutions is correlated not only to the case mix of their patients but also to the socioeconomic status of the patients admitted. The performance needs to be seen in light of patients’ socioeconomic status
Voting Rights, Agenda Control and Information Aggregation
No full textInternational audienceThis paper examines the comparative properties of voting rules based on the richness of their ballot spaces, assuming a given distribution of voting rights. We focus on how well voting rules aggregate the information dispersed among voters. We consider how different voting rules affect both voters’ decisions at the voting stage and the incentives of the agenda-setter, who decides whether to put the proposal to a vote. Without agenda-setter, the voting efficiency of rules is higher when their ballot space is richer. Moreover, full-information efficiency requires full divisibility of the votes. In the presence of an agenda-setter, we uncover a novel trade-off: in some cases, rules with high voting efficiency provide worse incentives to the agenda-setter to select good proposals. This negative effect can be large enough to wash out the higher voting efficiency of even the most efficient rules
Définition des mots âgisme et adultisme dans le cadre de recherches sur la mobilité.
No full textLes recherches du Laboratoire Ville, Mobilité, Transport (LVMT) se situent à l’intersection de l’aménagement, l’urbanisme, la géographie, l’économie, la sociologie, l’anthropologie et les sciences de l’ingénieur. Les « Mots du LVMT » sont une démarche collective initiée en 2016 par Florent le Néchet. Elle réunit désormais une cinquantaine de membres (actuels ou anciens) du laboratoire (chercheurs, enseignants-chercheurs, doctorants, post-doctorants, ingénieurs de recherche, ingénieurs d’études et chercheurs associés) autour d’un défi commun : expliciter, seul ou à plusieurs, les termes mobilisés dans nos recherches, en les replaçant dans les grands débats académiques et sociétaux. C'est dans ce cadre que nous proposons une définition des mots âgisme et adultisme dans le champ de la mobilité des personnes
3D-HEVC Fast Partionining Algorithm Based on MD-CNN
No full textInternational audienceThe introduction of the 3D-HEVC encoding standard has revolutionized the field of 3D and multi-view video by effectively synthesizing 3D video with adequate depth effects using depth map sequences. However, achieving this involves computationally intensive operations, such as the quad-tree partitioning of Intra Coding Units (CUs). Researchers used multiple approaches including heuristic, machine learning and deep learning to address this complexity. We opted to train a Multi-Deep Convolutional Neural Network (MD-CNN) model specifically for depth maps and integrated it into the 3D-HEVC encoder. This modified encoder uses the independent views as a reference to encode the dependent depth map views. This strategy reduces the complexity of the 3D-HEVC video encoder by 70.12% while slightly reducing video compression efficiency by 0.02% and a small Peak signal-to-noise ratio (PSNR) penalty of -0.80 dB
Weak redistribution and certainty equivalent domination
No full textInternational audienceWe assess optimal deterministic nonlinear income taxation in a Mirrlees economy with a continuum of risk‐averse agents whose utilities are quasilinear in labor. A weak redistribution motive makes random taxes more likely socially dominated by the deterministic policy where after‐tax income lotteries are replaced with their certainty equivalents
The Tibetan Plateau darkening initiates positive feedback through the Arctic
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Coordinating monetary and fiscal policies in Britain during the French Wars (1793–1821)
No full textInternational audienceRelying on new quantitative and qualitative data, we analyze how the United Kingdom financed the French Wars (1793–1821). We show that policy makers adjusted monetary and fiscal policies in four regimes. 1) tax-smoothing; 2) suspending the gold standard, real bills, war taxation; 3) the Bank of England's price support of government securities; 4) return to the old order. Under the price support regime, the Bank of England maintained the market value of public short-term debt by purchasing large amounts of it. Our findings suggest that in this context fiscal news shocks rather than fluctuations in the money supply caused inflation