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International audience; Calcium phosphate cements (CPC) have been widely investigated as bone substitutes, owing to their attractive features in terms of physicochemical and biocompatibility properties. However, the clinical applicability of this group of biomaterials is still critically limited by its poor strength and rheological properties in terms of injectability and cohesion. The present work aims to develop novel composite cement based on calcium phosphate cement (CPC) and bioactive glass (BG), associated with sodium alginate hydrogel (Alg). The composition, microstructure, setting, rheological, and mechanical properties of this composite cement were further investigated. Evaluation of setting properties showed that BG participates crucially in the setting reaction as a calcium and phosphate provider and serves as a setting accelerator. Thus, the setting time appears lower in these cements than in the reference CPC cement: it decreases from 75 to 42 min as the BG content increases from 10 to 25 wt% and is delayed from 42 to 73 min while the Alg amount augmented from 1 to 5 wt%. The rheological evaluation revealed that injectability was slightly improved with increasing BG content compared to the injectability of CPC, reaching a value close to 100% when combined with Alg hydrogel. The anti-washout property appeared to be weak for the CPC with or without BG, which are disintegrated in solution. The cohesiveness was significantly improved by introducing Alg hydrogel; furthermore, the addition of 5 wt% of alginate hydrogel induced an increase in the compressive strength about twice (7.2 MPa) higher than that of the reference CPC (4.0 MPa). According to the above findings, the addition of BG acts as a setting accelerator leading to a fast apatite formation, while the introduction of Alg hydrogel as a rheological promoting agent improves the injectability and cohesion. The combination of BG and Alg as additives increased the compressive strength compared to the reference cement.

The use of digital technologies and big data in the humanities and social sciences provided many opportunities for cultural heritage management and research, enabling data sharing and interdisciplinary collaborations. These developments increased the need for standardized data formats. General and domain-specific standards for describing and classifying cultural data, based on linked data principles, are developed to support increasingly numerous digital collections. However, the existing standards do not fully address the particular challenges concerning the standardized descriptions of images. Here we focus on ancient coins, an official image-bearing medium. We present current approaches to coin iconography, including the application of statistical measures to infer patterns in the use of images for communication. We discuss the importance of consistent, standardized data for quantitative research, and propose a generalized approach, focused on basic concepts and limiting the level of detail for the sake of simplicity, interoperability, and compatibility with statistical methods, as a necessary first step towards creating reliable iconographic standards. 1 Introduction 2 Coin images in the context of the digital revolution in numismatics 3 Measuring information in coin designs: the potentials and concerns of data standardization 4 The level of detail and statistical measures: the implications of coding decisions 5 Conclusion

Artificial language games give researchers the opportunity to investigate the emergence and evolution of semantic structure, i.e. the organisation of meaning spaces into discrete categories. A possible issue with this approach is that categories mightcarry over from participants’ native languages, a potential bias that has mostly been ignored. In a referential communication game, we compare colour terms from three different languages to those of an artificial language. We assess the similarity of the semantic structures and test the influence of the semantic structure on artificial language communication by comparing to a separate online naming task providing us with the native language semantic structure. Our results show that native and artificial language structures overlap at least moderately. Furthermore, communicative behaviour and performance were influenced by the shared semantic structure, but only for English-speaking pairs. These results imply a cognitive link between participants’ semantic structures and artificial language structure formation. Introduction Artificial language games, semantic structure, and possible biases Colour terms and categorical facilitation Method - The Color Game -- Participants -- Materials -- Procedure - Online survey -- Participants -- Materials -- Procedure - Predictions Results - Predictions 1 - Predictions 2.1 - Predictions 2.2 - Predictions 2.3 - Predictions 4 Discussion Conclusion

International audience; Phosphorene, a new two-dimensional material, was investigated theoretically as a promising photocatalyst material. The structural and electronic properties of phosphorene were studied using hybrid functional based HSE approximation. The effect of the adsorbed molecules on the phosphorene surface was studied for various chemical elements, such as water molecule (H2O), hydronium ion (H3O+), hydrogen atom and ion (H/H+), hydroxide molecule (OH), and hydroxide ion (OH−). The potential application of phosphorene as a photocatalyst in vacuum was proved under different pH values. A pH of 8 was found to be the suitable value for clean phosphorene in which the flat band position was corrected for the oxidizing and reducing potentials of phosphorene, but the presence of OH− ions in a basic solution damaged the surface structure and limited the use of phosphorene in photocatalysis caused by the high content (0.25 ML and 0.5 ML) of the adsorbed OH− on the phosphorene surface. The obtained results matched the required parameters of a photocatalyst for water splitting using clean phosphorene surface in neutral solution (pH = 7).

International audience; This study aimed to produce activated biochars (BCs) from Moroccan algae residue (AG) and olive pomace (OP) using mechanochemical activation with NaOH and ball milling (BM) for treating artificial textile wastewater containing methylene blue (MeB). The produced OP-activated BC by BM showed the highest absolute value of zeta-potential (-59.7 mV) and high removal efficiency of MeB compared to other activated BCs. The nonlinear pseudo-first-order kinetic model was the most suitable model to describe the kinetics of adsorption of MeB onto biochars produced from AG and the NaOH-activated BC from OP, whereas the nonlinear pseudo-second-order kinetic model suits the OP raw biochar and BM-activated BC. The nonlinear Langmuir isotherm model was the most suitable model for describing MeB adsorption onto BCs, compared to the nonlinear Freundlich isotherm model. The maximum adsorption capacities of AG-activated BCs with NaOH and BM were 13.1 and 9.1 mg/g, respectively, while those of OP-activated BCs were 2.6 and 31.8 mg/g, respectively. The thermodynamic study indicates the spontaneous and endothermic nature of the adsorption process of most activated BCs. In addition, Delta S degrees values indicate the increase of randomness at the solid-liquid interface during MeB sorption onto BC.

The aim of this paper is to investigate the impact of pretreating macroalgal residue (MAR) from agar-agar extraction and its co-digestion with sewage sludge on methane production and the agronomic quality of the digestates produced. First, different pretreatments were assessed on BMP tests. Among milling technologies used, knife milling with a 4 mm-screen improved methane production by 25%. The MAR was then knife milled before alkaline, acid and thermal pretreatment. KOH pretreatment (5% TS basis, 25 °C for 2 days) led to the highest methane improvement. It was applied to semi-continuous anaerobic digestion and methane production achieved 237 Nml/gVS which was 20% higher than the control (198 Nml/gVS). In comparison to MAR mono-digestion, co-digestion with thickened activated sludge produced less methane (184 Nml/gVS) but reduced H2S emission by 91%. None of the digestates was toxic for the germination or growth of wheat and tomato plants. Particularly, co-digestion had the highest impact on tomato plant dry weight (+94% compared to soil alone) mainly due to the phosphorous brought by sludge. However, the impact of alkaline pretreatment on plant growth was not significant.

Nanocrystalline titania was synthesized by a simple, innovative and eco-friendly gelation method by using biopolymers (polysaccharides). The effect of the gelling agent, such as carboxymethylcellulose (CMC) or alginate (Alg), and the drying routes (conventional drying at room temperature, or freeze-drying) on the properties and photocatalytic performances of nanostructured TiO 2 was examined. The crystallographic structures, and textural and morphological characteristics were investigated by thermogravimetric analysis (TGA), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy with energy dispersive spectrometry (ESEM-FEG-EDS), transmission electron microscopy (TEM), UV-vis diffuse reflectance spectroscopy (DRS) and N 2 adsorption/desorption isotherms. The as-synthesized samples were fully crystallized and appeared to be highly phase-pure anatase or mixed titania polymorphs, and have a quasi-spherical shape with a particle size ranging from 10.34 to 18.07 nm. Phase-pure anatase was obtained by using alginate as the gelling agent, whereas CMC's gelation promotes mixed structures. The presence of rutile phase results in a lower bandgap value of 3.04 eV corresponding to 408 nm. Thus, the material absorption wavelength shifts slightly from the UV (190-380 nm) to visible region (380-750 nm). The drying process also affects TiO 2 properties. The lyophilization route improves the oxide's specific surface area, and also its photocatalytic properties verified during Orange G dye photodegradation study.

International audience; Ba0.85Ca0.15Zr0.10Ti0.90O3 (BCZT) relaxor ferroelectric ceramics exhibit enhanced energy storage and electrocaloric performances due to their excellent dielectric and ferroelectric properties. In this study, the temperature-dependence of the structural and dielectric properties, as well as the field and temperature-dependence of the energy storage and the electrocaloric properties in BCZT ceramics elaborated at low-temperature hydrothermal processing are investigated. X-ray diffraction and Raman spectroscopy results confirmed the ferroelectric–paraelectric phase transition in the BCZT ceramic. At room temperature and 1 kHz, the dielectric constant and dielectric loss reached 5000 and 0.029, respectively. The BCZT ceramic showed a large recovered energy density (Wrec) of 414.1 mJ cm−3 at 380 K, with an energy efficiency of 78.6%, and high thermal-stability of Wrec of 3.9% in the temperature range of 340–400 K. The electrocaloric effect in BCZT was explored via an indirect approach following the Maxwell relation at 60 kV cm−1. The significant electrocaloric temperature change of 1.479 K at 367 K, a broad temperature span of 87 K, an enhanced refrigerant capacity of 140.33 J kg−1, and a high coefficient of performance of 6.12 obtained at 60 kV cm−1 make BCZT ceramics potentially useful coolant materials in the development of future eco-friendly solid-state refrigeration technology.

International audience; The analysis of the mechanical characteristics and dynamic behavior of fiberglass composite material structure used for perforation tests based on experimental results will be presented. This work is focused on perforation tests carried out at two ranges of temperatures (21 and 60 °C) and high strain rates. By using the specially designed thermal chamber to heat specimens before impact. Based on this experimental series, the ballistic properties of the material impacted by a conical nose shape projectile is studied. The complete energy balance is also reported and the absorbed energy by the composite sheet has been obtained by measuring initial and residual projectile velocities. A wide range of impact velocities from 40 to 123 m/s has been covered during the tests. The projectile has a diameter of 12 mm and the plate has 4 mm thickness. The main objective of this work is to study the behavior of the composite material specimens during the impact. To study the temperature effects, two different temperatures were used material, at room temperature and 60 °C. The time needed to heat the specimen and to stabilize its temperature is 15 min.

The main objective of this work was to study the possibility of using polysaccharides and lignin as a coating material for water-soluble triple superphosphate (TSP) granular fertilizers. In this study, composites based on three polysaccharides (sodium alginate (alginic acid sodium salt): AL, kappa-carrageenan: CR and carboxymethyl cellulose sodium salt: CM) and lignin (LG) were prepared. The lignin used was extracted from olive pomace (OP) biomass using the alkali method. The morphological, mechanical, and surface properties as well as the thermal behavior of the coatings were characterized and compared. Their morphology and thickness revealed by scanning electron microscopy (SEM) showed good adhesion between the fertilizer and coating materials. The results showed that the lignin-carrageenan formulation (LGCR) exhibited the highest water absorbency and elastic modulus. Release tests showed the effect of the TSP/biopolymer mass ratio and that the slowest P release was obtained with the LGCR@TSP formulation composite within 3 day. In addition, 59.5% and 72.5% of P was released after 3 days with the TSP/biopolymer mass ratios of 5/1 and 15/1, respectively, compared to 100% P release with the uncoated TSP.

International audience; Tetracycline (TC) is one of the antibiotics that is found in wastewaters. TC is toxic, carcinogenic, and teratogenic. In this study, the tetracycline was removed from water by adsorption using dioxide silicon nanoparticles (SiO2 NPs) biosynthesized from the extract of Nerium oleander leaves. These nanoparticles were characterized using SEM-EDX, BET-BJH, FTIR-ATR, TEM, and XRD. The influences of various factors such as pH solution, SiO2 NPs dose, adsorption process time, initial TC concentration, and ionic strength on adsorption behaviour of TC onto SiO2 NPs were investigated. TC adsorption on SiO2 NPs could be well described in the pseudo-second-order kinetic model and followed the Langmuir isotherm model with a maximum adsorption capacity was 552.48 mg/g. At optimal conditions, the experimental adsorption results indicated that the SiO2 NPs adsorbed 98.62% of TC. The removal of TC using SiO2 NPs was 99.56% at conditions (SiO2 NPs dose = 0.25 g/L, C0 = 25 mg/L, and t = 40 min) based on Box-Behnken design (BBD) combined with response surface methodology (RSM) modelling. Electrostatic interaction governs the adsorption mechanism is attributed. The reusability of SiO2 NPs was tested, and the performance adsorption was 85.36% after the five cycles. The synthesized SiO2 NPs as promising adsorbent has a potential application for antibiotics removal from wastewaters.

In this paper, two different approaches for tumor growth modeling are presented and implemented. In the first part of the paper, a macroscopic approach using a PDE model, where the tumor is viewed as a cell mass, is implemented using the level-set method to track the tumor moving boundary in one hand by using Darcy’s law to compute the normal velocity of the free boundary and on the other hand using the shape optimization to draw the normal velocity. In the second part of the paper, a microscopic approach, which focuses on the cellular scale, is presented. A hybrid model using agent-based modeling for the cell behavior and a PDE for the description of the tumor environment is presented. A sensitivity analysis is performed on the hybrid model for a better understanding of its impact on the tumor growth. Numerical experiments are provided for the proposed approaches.

In this paper, we investigate how Leadership Style, Organizational Design, and HRM practices influence Knowledge Hiding. Organizational Justice and Competitive Work Environment are additionally considered as mediating variables of these impacts. 224 professionals completed an extensive survey with questions corresponding to the hypothesized effects. Based on partial least squares regression to test these hypotheses, this study shows that Leadership Style and Organizational Design mitigate Knowledge Hiding only when Organizational Justice is developed. While HRM practices can also decrease the intention of employees to hide knowledge in cases with high levels of justice, they may induce such behavior in a highly competitive work environment. Hence, this research contributes to knowledge management literature by examining the joint influence on knowledge hiding of organizational factors that genuinely describe an organization’s structure and climate. From a practical standpoint, we recommend that managers establish the right balance between justice and competition to reduce knowledge hiding.

International audience; Coastal wetlands are highly sensitive to changes occurring at the coastline. It is critically important to determine region-specific projections for these areas due to their specificities and vulnerabilities to climate change. This work aimed to value the impacts of recent climate changes at West Africa Sahara coastland, southern Morocco, at Khnifiss Lagoon. We have applied a combined approach using remote sensing techniques and environmental reconstructions based on high-resolution analysis of sediment cores, covering the current warm period. Remote sensing highlighted changes to the lagoon inlet, accompanied by a greater meandering character of the tidal channels. As a response, the sediment cores have recorded a predominant vegetation substitution due to changes in the tidal limit, and an increase in organic carbon accumulation was observed. For the current climatology, during positive phases of the North Atlantic Oscillation, winds reaching the coast strengthen in an east-to-west direction. In the Khnifiss Lagoon, whose inlet is dominated by the ebb tide, the intensity and direction of the winds on the coast at surface level modifies its connection to the ocean by increasing sediment transport toward the interior of the lagoon. Locally biological responses to wind intensification, and possibly sea-level rise, exemplify the lagoon sensitivity to large-scale processes. Coastal vegetated wetlands are considered to be highly dynamic environments. However, we expect a loss of the upper tidal vegetation due to boundary conditions limiting the accommodation space in this arid environment in a possible future scenario of continuously inland tidal line displacement.

International audience; Accompagner à distance des étudiants lors de stages virtuels basés sur la vidéo 360° L'objet de la présente communication est de décrire l'usage d'un dispositif de vidéoformation en ligne dans le cadre de la formation préprofessionnelle des enseignants en France. L'étude a été menée auprès d'étudiants inscrits en 2 e année universitaire se destinant à devenir enseignant d'éducation physique. Cette étude a été menée dans le cadre du programme de recherche du cours d'action (Theureau, 2010) selon deux postulats : celui de l'expérience vécue des usagers et celui de l'énaction. Par son interaction avec l'environnement, l'individu fait advenir sa réalité, des phénomènes signifiants pour lui (Varela, 2017) que le chercheur s'attache à décrire grâce à des entretiens d'autoconfrontation (Theureau, 2010). Les résultats de l'étude rendent compte de l'activité conjointe du formateur et de l'étudiante participante et de la dynamique de coconstruction des connaissances au cours du processus d'enseignementapprentissage. Lors du TD en ligne, le formateur a organisé son activité dans l'objectif de développer chez les étudiants des compétences d'observation et d'analyse des conduites motrices des élèves visualisés dans la vidéo 360°. Ainsi, il s'est attaché à transformer, grâce aux possibilités technologiques offertes par la vidéo 360°, les focalisations attentionnelles de l'étudiante vers des phénomènes perceptifs pertinents pour comprendre et analyser l'activité motrice des élèves.

International audience; Multi-function radars require efficient resource management strategies to fulfill their missions. In particular, task scheduling is crucial to mitigate difficult situations such as when all tasks cannot be accomplished. However, current approaches may prove insufficient in the face of emerging threats. In this article, we present a new formulation for the scheduling problem. Our model allows building schedules in a flexible way, which facilitates the discovery of high-value solutions using heuristics or tree search. We show that our algorithms provide noticeable performance improvement over similar methods proposed previously.

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The azobenzene 1-arylazo-2-naphthol has been synthesized and characterized by elemental analysis, 1H NMR, IR and UV–Vis spectroscopies using both experimental and theoretical methods. The MEP, NPA and FMOs have also been performed at the DFT/B3LYP-D3 level with different solvents in order to investigate the solvent's effect. The energetic behavior of the compound has been examined in the gas phase and in solvent media using the integral equation formalism polarizable continuum model (IEF-PCM). Solvents had sligth significant effect on NPA values whereas both molecules hardness and stability decrease along with increasing of the solvent's polarity. Vibrational and absorption analysis showed no significant azo±hydrazone tautomerism. Theorically, the title molecule calculated in Acetonitrile solvent is the most reactive. The observed red shifts are explained by the large extension of the π conjugated system and the blue shifts confirm the appearance of several tautomeric forms of the studied azo-benzene which lead to a marked improvement in photochemical stability. The cation binding properties of azo benzene as absorption sensor for Cu2+, Mg2+, Ni2+ and Zn2+ cations were reported. The highest adsorption energy in both gas and liquid phase corresponds to the complexes Azoic/Ni2+ then in Azoic/Cu2+ and somewhat in Azoic/Zn2+complex. The lowest adsorption energy is given to Azoic/Mg2+ complex. After cations chemisorption on azoic molecule a bathochromic shift is observed in the optical spectra, particularly for Azoic/Ni2+ complex, which is the proof of interaction between azoic compound and mentioned cations. The electronic proprieties and the vibrational spectra can therefore be used to detect the presence of different cations and the azobenzene shows appropriate properties to constitute good cations (Ni2+ and Cu2+) sensors.

The mechanical behavior at contact points in high-voltage electrical cable conductors is simulated to find where damage may occur. The presented approach is based on a numerical model that is referred to as the wire model. The critical zones are detected by simulating the mechanical behavior of a cable conductor section with a large number of contacts. For the wire model, a relevant regularized contact law that improves convergence of the contact algorithm compared to the standard contact law is implemented. This model is validated by making comparisons with experimental results available in the literature for various conductors. However, this approach employs a costly finite element method. In order to reduce the evaluation cost and allow sensitivity analysis of the input parameters, a surrogate model is proposed to replace the initial wire model. The surrogate model approximates the input–output relationship of the costly wire model. The choice of the sampling method that allows selection of the best fitting surrogate model for this application is discussed, but comparisons show little influence on the obtained scores. The robustness of the obtained result depends mostly on the chosen surrogate model, where the scores obtained with random forest and neural network are better than the scores obtained with linear and polynomial regression. The application is the French high-voltage network, but the work is relevant for any other network.

Today's large-scale algorithms have become immensely influential, as they recommend and moderate the content that billions of humans are exposed to on a daily basis. They are the de-facto regulators of our societies' information diet, from shaping opinions on public health to organizing groups for social movements. This creates serious concerns, but also great opportunities to promote quality information. Addressing the concerns and seizing the opportunities is a challenging, enormous and fabulous endeavor, as intuitively appealing ideas often come with unwanted {\it side effects}, and as it requires us to think about what we deeply prefer. Understanding how today's large-scale algorithms are built is critical to determine what interventions will be most effective. Given that these algorithms rely heavily on {\it machine learning}, we make the following key observation: \emph{any algorithm trained on uncontrolled data must not be trusted}. Indeed, a malicious entity could take control over the data, poison it with dangerously manipulative fabricated inputs, and thereby make the trained algorithm extremely unsafe. We thus argue that the first step towards safe and ethical large-scale algorithms must be the collection of a large, secure and trustworthy dataset of reliable human judgments. To achieve this, we introduce \emph{Tournesol}, an open source platform available at \url{https://tournesol.app}. Tournesol aims to collect a large database of human judgments on what algorithms ought to widely recommend (and what they ought to stop widely recommending). We outline the structure of the Tournesol database, the key features of the Tournesol platform and the main hurdles that must be overcome to make it a successful project. Most importantly, we argue that, if successful, Tournesol may then serve as the essential foundation for any safe and ethical large-scale algorithm., 27 pages, 13 figures

International audience; A composite based on hydroxyapatite (HA) and chitosan (CS) combined with ciprofloxacin (CIP) was formulated by the solid-liquid mixing method. The optimization of the solid to the liquid ratio and the use of chitosan in a small amount (

International audience; The solid waste of olive oil extraction processes (olive pomace (OP)) was converted into activated carbon (AC) through merely treating it with NaOH and then encapsulating it within sodium alginate (SA) in beads by crosslinking (SA-AC beads). The prepared SA-AC beads were utilized as an adsorbent for the elimination and recovery of phenolic compounds (PCs) from olive mill wastewater (OMWW) following a zero liquid and waste discharge approach to implement and promote the circular economy concept. The novel AC and SA-AC beads were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR) and Brunauer, Emmett and Teller (BET) analysis. The adsorption performance of these beads was evaluated in batch and fixedbed reactors operated in a concurrent flow system. The results revealed that an adsorption capacity of 68 mg g-1 was attained for 4,000 mg L-1 phenolic compounds. The kinetics of the adsorption process of the PCs fit a pseudo second-order model, and the most likely mechanism took place in two stages. The adsorption isotherm conformed to the Langmuir model, representing the monolayer adsorption of the phenolic compounds. The dynamic models were used, and they accurately represented the breakthrough curves. Considering PC recovery and process reusability, a regeneration experiment of SA-AC beads was carried out in fixed-bed reactors. SA-AC beads showed a high percentage desorption > 40% using ethanol and were efficient after several cycles of OMWW treatment and phenol recovery.

International audience; 360° video offers a valuable tool for bridging coursework and fieldwork during pre-service teacher internships. The purpose of this study was to explore the usefulness of 360° video integration into the scaffolding of pre-service teacher education. Quantitative feedback from 82 student teachers during a teacher education course showed a general preference for 360° video based on improving an increased noticing of teaching and students’ classroom activity. A qualitative analysis of one teachers’ learning experiences using 360° video (based on reflections gathered from a self-confrontation interview) showed an increased perceptual immersion, enhanced attentional capacity, and teaching situation discovery (i.e., better classroom observing). Based on the results, we find 360° video has stronger immersive qualities compared to 2D video and augmented experience, providing a different way to learn teaching skills through reflection on one’s own or another’s teaching practice. Due to its affordability and usability, 360° video can be seen to enrich internships and allow for "virtual internship" experiences to prepare for real classroom situations.

International audience; 3-Mercaptopropionic acid (MPA)-capped Mn-doped ZnSe/ZnS and CdTe/CdS core/shell quantum dots (QDs) were prepared via a mild aqueous phase process. The synthesis conditions were adjusted to yield QDs with roughly similar nanocrystal average diameter and light emission wavelengths. X-ray powder diffraction, transmission electron microscopy and spectrofluorometry have been used to characterize the crystal structure and optical properties of the as-prepared QDs. Growth inhibition tests using E. coli bacterial cells were also carried out to assess the cytotoxicity of the dots and showed that core/shell ZnSe:Mn/ZnS@MPA QDs do not exhibit any cytotoxicity against E. coli cells up to a concentration of 14 μM while at this concentration CdTe/CdS@MPA core/shell QDs exert a severely more pronounced cytotoxicity. These results indicate that the cytotoxicity is likely associated to the presence of Cd in the chemical composition of CdTe/CdS@MPA QDs and that ZnSe:Mn/ZnS@MPA nanocrystals are safer and could be used as biological probes for cells and tissues imaging.

International audience; Microalgae are considered potential candidates in biorefinery processes, and due to their biochemical properties, they can be used in the production of biofuels such as biogas, as well as for bioremediation of liquid effluents. The objective of this review is to study the current status of microalgae anaerobic digestion and agricultural uses (as bio-stimulants and biofertilizers), starting from microalgae cultivation. Indeed, the efficiency of these processes necessarily depends on the evaluation of different biotic and abiotic factors that affect the growth of microalgae. However, the adaptation and the optimization of process parameters on a large scale is also limited by energy and economic constraints. Moreover, the integration of biogas production processes with microalgae cultivation allows a nutrients and CO 2 virtuous loop, thus promoting the sustainability of the process. Finally, this paper provides a general overview of biogas and biofertilizers production combination, as well as the related challenges and recommended future research perspectives to complement the gap in the literature.

International audience; Accurate seasonal forecasting of cereal yields is an important decision support tool for countries, such as Morocco, that are not self-sufficient in order to predict, as early as possible, importation needs. This study aims to develop an early forecasting model of cereal yields (soft wheat, barley and durum wheat) at the scale of the agricultural province considering the 15 most productive over 2000–2017 (i.e., 15 × 18 = 270 yields values). To this objective, we built on previous works that showed a tight linkage between cereal yields and various datasets including weather data (rainfall and air temperature), regional climate indices (North Atlantic Oscillation in particular), and drought indices derived from satellite observations in different wavelengths. The combination of the latter three data sets is assessed to predict cereal yields using linear (Multiple Linear Regression, MLR) and non-linear (Support Vector Machine, SVM; Random Forest, RF, and eXtreme Gradient Boost, XGBoost) machine learning algorithms. The calibration of the algorithmic parameters of the different approaches are carried out using a 5-fold cross validation technique and a leave-one-out method is implemented for model validation. The statistical metrics of the models are first analyzed as a function of the input datasets that are used, and as a function of the lead times, from 4 months to 2 months before harvest. The results show that combining data from multiple sources outperformed models based on one dataset only. In addition, the satellite drought indices are a major source of information for cereal prediction when the forecasting is carried out close to harvest (2 months before), while weather data and, to a lesser extent, climate indices, are key variables for earlier predictions. The best models can accurately predict yield in January (4 months before harvest) with an R2 = 0.88 and RMSE around 0.22 t. ha−1. The XGBoost method exhibited the best metrics. Finally, training a specific model separately for each group of provinces, instead of one global model, improved the prediction performance by reducing the RMSE by 10% to 35% depending on the provinces. In conclusion, the results of this study pointed out that combining remote sensing drought indices with climate and weather variables using a machine learning technique is a promising approach for cereal yield forecasting.

Mine tailings exposed to water and oxygen generate acid mine drainage (AMD) when the neutralizing minerals are insufficient to buffer the acid produced by sulfide oxidation. Mineral reactivity, such as sulfide oxidation and carbonate dissolution, leads to several changes within mine tailings in terms of their physical, mineralogical, and geochemical properties, which may lead to the release of metal(oid)s (e.g., As, Cu, Zn, Fe, S) into the environment. Fresh and oxidized tailings were sampled at two vertical profiles in a tailings storage facility (TSF). The TSF contains tailings from gold ore processing at a mine that has been closed for more than 25 years. Oxidized tailings have formed by in-situ oxidation of fresh tailings over more than 20 years. The collected samples were analyzed for: i) chemical composition by inductively coupled plasma atomic emission spectroscopy (ICP-AES), X-ray fluorescence (XRF), and total S/C; and ii) mineralogical composition by X-ray diffraction (XRD), Mineral Liberation Analyzer (MLA), Mossbauer spectroscopy, and Fe L-edge X-ray absorption near-edge spectroscopy (XANES). Mineralogically, the fresh tailings included more than 22 wt% carbonates and more than 10 wt% sulfides. In contrast, the oxidized tailings were composed mainly of secondary minerals such as iron oxy-hydroxides and gypsum. Geochemically, the fresh tailings exhibited a circumneutral behavior during weathering cell experiments and contaminants such as As were negligibly released (

International audience

International audience; Pharmaceutical products have become a necessary part of life. Several studies have demonstrated that indirect exposure of humans to pharmaceuticals through the water could cause negative effects. Raw sewage and wastewater effluents are the major sources of pharmaceuticals found in surface waters and drinking water. Therefore, it is important to consider and characterize the efficiency of pharmaceutical removal during wastewater and drinking-water treatment processes. Various treatment options have been investigated for the removal/reduction of drugs (e.g., antibiotics, NSAIDs, analgesics) using conventional or biological treatments, such as activated sludge processes or bio-filtration, respectively. The efficiency of these processes ranges from 20-90%. Comparatively, advanced wastewater treatment processes, such as reverse osmosis, ozonation and advanced oxidation technologies, can achieve higher removal rates for drugs. Pharmaceuticals and their metabolites undergo natural attenuation by adsorption and solar oxidation. Therefore, pharmaceuticals in water sources even at trace concentrations would have undergone removal through biological processes and, if applicable, combined adsorption and photocatalytic degradation wastewater treatment processes. This review provides an overview of the conventional and advanced technologies for the removal of pharmaceutical compounds from water sources. It also sheds light on the key points behind adsorption and photocatalysis.

Background Increasing crop production to feed a growing population has driven the use of mineral fertilizers to ensure nutrients availability and fertility of agricultural soils. After nitrogen, phosphorus (P) is the second most important nutrient for plant growth and productivity. However, P availability in most agricultural soils is often limited because P strongly binds to soil particles and divalent cations forming insoluble P-complexes. Therefore, there is a constant need to sustainably improve soil P availability. This may include, among other strategies, the application of microbial resources specialized in P cycling, such as phosphate solubilizing bacteria (PSB). This P-mediating bacterial component can improve soil biological fertility and crop production, and should be integrated in well-established formulations to enhance availability and efficiency in use of P. This is of importance to P fertilization, including both organic and mineral P such as rock phosphate (RP) aiming to improve its agronomic efficiency within an integrated crop nutrition system where agronomic profitability of P and PSB can synergistically occur. Aim of Review The purpose of this review is to discuss critically the important contribution of PSB to crop P nutrition in concert with P fertilizers, with a specific focus on RP. We also highlight the need for PSB bioformulations being a sustainable approach to enhance P fertilizer use efficiency and crop production. Key Scientific Concepts of Review We first recognize the important contribution of PSB to sustain crop production, which requires a rational approach for both screening and evaluation of PSB enabling an accurate assessment of the bacterial effects both alone and in intertwined interaction with plant roots. Furthermore, we propose new research ideas about the development of microbial bioformulations based on PSB with a particular focus on strains exhibiting synergetic effects with RP.

Communication du 28 juin 2021; International audience

International audience

International audience; The genus Vigna (Fabaceae) is an agriculturally important taxon, which includes several crop species such as cowpea (Vigna unguiculata L), mung bean (Vigna radiata) and azuki bean (Vigna angularis). Most studies have focused on cowpea (Vigna unguiculata (L.) as a drought‐resistant crop, although insights on the mechanisms that confer this species the ability to grow in dry environment are still not fully resolved. The diversity of this rich genus has been overlooked in many physiological studies. This study explores the physiological mechanisms of response to soil drying (N2 fixation, transpiration rate and changes in C and N allocation) across three species of the Vigna genus: Vigna radiata, Vigna unguiculata, Vigna vexillata (tuber cowpea). A significant variability among the studied Vigna accessions was found for the threshold in decline of N2 fixation with soil drying. Less variability was observed in the transpiration threshold. Through the analysis of leaf traits variation under well‐watered and water‐deficit conditions, we were able to relate the variability in N2 fixation and transpiration response to C/N metabolism modifications resulting in different allocation of carbon and nitrogen to leaves under water deficit.

International audience; Mining produces significant amounts of solid mineral waste. Mine waste storage facilities are often challenging to manage and may cause environmental problems. Mining waste is often linked to contaminated mine drainage, including acidic waters with more or less elevated concentrations of trace metals such as lead. This work presents a study on the mobilization of lead from waste from two typical mining sites: Zeida and Mibladen, two now-closed former Pb–Zn mines in the Moulouya region of Morocco. Our research investigates the mobilization potential of Pb from the waste of these mines. The study involved acid–base neutralization capacity tests (ANC–BNC) combined with geochemical modeling. Experimental data allowed for the quantification of the buffering capacity of the samples and the mobilization rates of lead as a function of pH. The geochemical model was fitted to experimental results with thermodynamic considerations. The geochemical model allowed for the identification of the mineral phases involved in providing the buffering capacity of carbonated mining waste (Mibladen) and the meager buffering capacity of the silicate mining waste (Zeida). These cases are representative of contaminated neutral drainage (CND) and acid mine drainage (AMD), respectively. The results highlight the consistency between the ANC–BNC experimental data and the associated modeling in terms of geochemical behavior, validating the approach and identifying the main mechanisms involved. The modeling approach identifies the dissolution of the main solid phases, which impact the pH and the speciation of lead as a function of the pH. This innovative approach, combining ANC–BNC experiments and geochemical modeling, allowed for the accurate identification of mineral phases and surface complexation phenomena, which control the release of lead and its speciation in drainage solutions, as well as within solid phases, as a function of pH.

International audience; Anaerobic digestion (AD) is a waste treatment technology based on organic matter degradation by microorganisms in the absence of oxygen. This process generates two valuables products, biogas and digestate. While biogas is recognized and exploited for its energy potential, digestate could be an interesting fertilizer thanks to its rich-nutrient composition. However, implementation of AD still raises concerns about energy transportation, consequences of digestate spreading and poor conversion to carbon during digestion. To overcome the issues linked to AD, to integrate anaerobic digestion with the pyrolysis of digestate is an innovate path. This study aims to analyze sustainability of a multifunctional process coupling anaerobic digestion and pyrolysis. The process is applied to the treatment of sewage sludge and quinoa residue in co-digestion. To evaluate environmental impacts, life cycle assessment (LCA) is realized from a cradle-to-gate perspective, using SimaPro software (V8.5.2) and Environmental Footprint EF 3.0 method. Results underline that the main contributor to environmental impacts is the treatment of bio-oil, a pyrolysis product, while other impacts could be counterbalance thanks to energy production

The Kef Essennoun phosphorite deposit belonging to the Djebel Onk–Gafsa–Metlaoui Basin is the most important phosphorite deposit in Algeria. It occurs as a monocline layer with an average thickness of 35 m, dipping 10° to 15° southward and bounded to the west by the Ain Fouris shoal. The deposit displays two ore facies, the black and the brown ores, which are stacked obliquely and show internal layering with swaley cross-stratification and large-scale high-angle cross-bedding. To investigate the phosphorite depositional and hydrodynamic settings, grain size analysis and sequential Gaussian simulation of P2O5 contents from 29 drill holes were performed. Results of grain size analysis reveal that a marine flooding event associated with the Thanetian transgression involved the transport and reworking of phosphatic materials by paleocurrents in a medium-energy environment and their disposition as a shoreface deposit. The simulation indicates the disposition of the phosphorite formation in at least three superimposed bodies elongated N63°, parallel to the Ain Fouris shoal. These results are consistent with morphodynamic responses to sedimentological and oceanographic processes involving the interaction of paleocurrents with substrate morphology. The black ore facies has preserved features of the pristine phosphate indicating that the deposit was not significantly displaced away from the phosphogenesis zone. Reworked facies and sedimentary structure patterns associated with the shoreface environment allow us to interpret the Kef Essennoun phosphorites as tempestites concentrated from pristine phosphates through storm-wave winnowing.

This paper deals with the development of a thermodynamic-based model for the prediction of fouling phenomena in a wet phosphoric acid process. The developed model is based on mass and heat balances along with equations of Pitzer's thermodynamic model. It involves several unknown parameters that should be identified from experimental data. For this purpose, a database of experimental measurements carried out in this work, and other measurements from the literature are used. The comparison of the available measurements to the predictions generated using the values of the identified parameters shows the high performance of the developed model. Furthermore, the model is used to predict thermodynamic saturation indices of the main minerals that are likely to precipitate during the digestion process, and may cause fouling. A global sensitivity algorithm is finally used to determine the operating parameters that most influence the precipitation of these mineral phases. The results are very consistent with previous works and with the measurements carried out on industrial plants. Moreover, they explain many dysfunctions observed in phosphoric acid production facilities.

We present a systematic approach to construct complete equations of state (EOSs), or to ensure thermodynamic consistency of complete and incomplete forms of EOSs using a minimal and sufficient set of relations. We apply the proposed approach to some common classical equations of state for pure materials. In fact, classical equations of state come generally in an incomplete form that hides essencial properties necessary for thermodynamic consistency. If not aware of such constraints one may generalize the EOS, or fit its thermodynamic parameters from emprirical data in an inconsistent way.

International audience

This work reports on the preparation of oil-filled microcapsules for self-healing purposes. Biopolymeric microcapsules loaded with vegetable oils as green corrosion inhibitors were formulated using ethyl cellulose and phosphorylated ethyl cellulose as encapsulating materials. Chemical structure, thermal stability and surface morphology of microcapsules were characterized by Fourier transform infrared (FTIR) spectroscopy, thermal gravimetric analysis (TGA) and scanning electron microscopy (SEM). FTIR and TGA analysis confirmed the presence of oil core and polymer shell in the formulated microcapsules. The scanning electron microscopy was used to evaluate the shape and morphology of the prepared microcapsules. The obtained results revealed the spherical-like shape of the obtained capsules with diameters ranging from 10 up to 170 µm. Thus, the current study shows the potential application of phosphorylated ethyl cellulose for the development of new environmentally friendly microcontainers bearing corrosion inhibitors for end use in anti-corrosion self-healing coatings.

International audience

International audience; Crop diversity management in agriculture is a fundamental principle of agroecology and a powerful way to promote resilient and sustainable production systems. Pulses are especially relevant for diversification issues. Yet, the specific diversity of legumes is poorly represented in most cropping systems. We used the trait-based approach to quantify the functional diversity of 30 pulses varieties, belonging to 10 species, grown under common field conditions. Our aim was to test relationships between traits, yield, and supporting agroecosystem properties. Our experimental results highlighted trade-offs between agroecosystem properties supported by different combinations of traits. Also, results demonstrated the relevance of leaf nitrogen content (LNC), leaf area ratio (LAR), and reproductive phenology to predict most of the trade-offs observed between agroecosystem properties. A comparison with a previous analysis based on literature data collected in diverse agronomic situations suggested that some traits are more plastic than others and therefore contribute differently to frame legumes diversity depending on the conditions of observation. Present results suggested that the implementation of such trait-based approach would rapidly benefit the selection of species/varieties for specific targeted agroecosystem services provisioning under specific (environmental or management) conditions.

International audience; The 2030 Agenda for Sustainable Development aims to reach 17 Sustainable Development Goals (SDGs). The SDGs 6 deals with water security, which refers mainly to ensure availability and sustainable management of water. The present study aims to enhance reservoir performance under climate change to deal with water scarcity. For this purpose, we proposed a new methodology where precipitation and evaporation data provided through temporal downscaling are leveraged by a real-time management algorithm coupled with the Hydrologic Modeling System (HEC-HMS). The real-time dam management algorithm is based on water balance equation and rule curves. It provides information about (1) dam storage, (2) dam release, (3) dam evaporation, (4) dam diversion, (5) spilled water volume, (6) emergency spilled water volume, (7) dam inflow, (8) irrigation demand, (9) irrigation shortage, (10) dam siltation, (11) dam hydropower production , (12) hydropower energy income. The developed approach has been applied to the Hassan Addakhil multipurpose reservoir in Morocco. The result shows that the dam reliability and resilience have increased from 40% to 70% and from 16% to 66%, respectively, while the vulnerability remained constant. Additionally, this study has pointed out that the installation of a hydropower plant is an opportunity to produce clean electrical energy and generate an income enough to cover different costs related to dam management and maintenance. Therefore, the real-time management tool developed in the framework of this project can significantly enhance reservoir performance .

International audience; The sustainability of the anaerobic digestion industry is closely related to proper digestate disposal. In this study, an innovative cascading biorefinery concept coupling anaerobic digestion and subsequent pyrolysis of the digestate was investigated with the aim of enhancing the energy recovery and improving the fertilizers from organic wastes. Continuous anaerobic co-digestion of quinoa residues with wastewater sludge (45/55% VS) exhibited good stability and a methane production of 219 NL CH4/kg VS. Subsequent pyrolysis of the solid digestate was carried out (at 500 °C, 1 h, and 10 °C/min), resulting in a products distribution of 40 wt% biochar, 36 wt% bio-oil, and 24 wt% syngas. The organic phase (OP) of bio-oil and syngas exhibited higher and lower heating values of 34 MJ/kg and 11.8 MJ/Nm3, respectively. The potential synergy of coupling biochar with liquid digestate (LD) for agronomic purposes was investigated. Interestingly, coupling LD (at 170 kg N/ha) with biochar (at 25 tons/ha) improved the growth of tomato plants up to 25% compared to LD application alone. In parallel, co-application of biochar with LD significantly increased the ammonia volatilization (by 64%) compared to LD application alone, although their simultaneous use did not impact the C and N mineralization rates.

Structureless communications such as Device-to-Device (D2D) relaying are undeniably of paramount importance to improving the performance of today’s mobile networks. Such a communication paradigm requires a certain level of intelligence at the device level, thereby allowing it to interact with the environment and make proper decisions. However, decentralizing decision-making may induce paradoxical outcomes, resulting in a drop in performance, which sustains the design of self-organizing yet efficient systems. We propose that each device decides either to directly connect to the eNodeB or get access via another device through a D2D link. In the first part of this article, we describe a biform game framework to analyze the proposed self-organized system’s performance, under pure and mixed strategies. We use two reinforcement learning (RL) algorithms, enabling devices to self-organize and learn their pure/mixed equilibrium strategies in a fully distributed fashion. Decentralized RL algorithms are shown to play an important role in allowing devices to be self-organized and reach satisfactory performance with incomplete information or even under uncertainties. We point out through a simulation the importance of D2D relaying and assess how our learning schemes perform under slow/fast channel fading.

International audience; We study Density Functional Theory models for systems which are transitionally invariant in some directions, such as a homogeneous 2-d slab in the 3-d space. We show how the different terms of the energy are modified and we derive reduced equations in the remaining directions. In the Thomas-Fermi model, we prove that there is perfect screening, and provide precise decay estimates for the electronic density away from the slab. In Kohn-Sham models, we prove that the Pauli principle is replaced by a penalization term in the energy. In the reduced Hartree-Fock model in particular, we prove that the resulting model is well-posed, and provide some properties for the minimizer.

Scientific projects frequently involve measurements of thermophysical, thermochemical, and other related properties of chemical compounds and materials. These measured property data have significant potential value for the scientific community, but incomplete and inaccurate reporting often hampers their utilization. The present IUPAC Technical Report summarizes the needs of chemical engineers and researchers as consumers of these data and shows how publishing practices can improve information transfer. In the Report, general principles of Good Reporting Practice are developed together with examples illustrating typical cases of reporting issues. Adoption of these principles will improve the quality, reproducibility, and usefulness of experimental data, bring a better level of consistency to results, and increase the efficiency and impact of research. Closely related to Good Reporting Practice, basic elements of Good Research Practice are also introduced with a goal to reduce the number of ambiguities and unresolved problems within the thermophysical property data domain.

International audience; The development of phase change materials (PCM) for thermal energy storage is a promising technology. However, the liquid PCM leaks and low thermal conductivity limit the practical PCM applications. This article aims to solve these problems; it presents the preparation and thermal characterisation of PCM enhanced by carbon-based nanoparticles. The polyethene glycol 6000 (PEG 6000) is used as PCM and multi-walled carbon nanotubes (MWCNTs) as a shell matrix and thermal conductivity enhancer. The sample was prepared by the sonification method under vacuum conditions. Fourier transform infra-red spectroscopy (FT-IR) and thermo-gravimetric analysis (TGA) tested the chemical and thermal compatibility of the prepared samples. The storage performances are tested by modulated differential scanning calorimetry characterisation. The nano-enhanced-PCM (NPCM) with 1 wt% MWCNTs showed excellent shape stability without any liquid leakage when the temperature was about 110 °C for 30 minutes. Drying method has a significant effect on the thermal storage capacity of the NPCM. The melting, solidification points and the latent heats of the NPCM were measured as 61.75, 35.50 °C, and 174.24, 167.84 J g−1, respectively. Meanwhile, the specific heat is 2.63 J g−1°C−1 for the solid-state and 2.14 J g−1°C−1 for the liquid-state. The thermal conductivity of pristine PEG was improved by 49%.

The 2 Ga-old Ihouhaouene alkaline complex (Western Hoggar, Algeria) is among the oldest known carbonatite occurrences on Earth. The carbonatites are calciocarbonatites hosted by syenites, the predominant rock type in the complex. Both rock types are characterized by medium-grained to pegmatitic textures and contain clinopyroxene, apatite, and wollastonite, associated with K-feldspar in syenites and a groundmass of calcite in carbonatites. The rock suite shows a continuous range of compositions from 57–65 wt.% SiO2 and 0.1–0.4 wt.% CO2 in red syenites to 52–58 wt.% SiO2 and 0.1–6.5 wt.% CO2 in white syenites, 20–35 wt.% SiO2 and 11–24 wt.% CO2 in Si-rich carbonatites (>10% silicate minerals), and 2 and 24–36 wt.% CO2 in Si-poor carbonatites (50), whereas clinopyroxene was precipitated from silicate liquids characterized by lower LREE/HREE (Ce/Lu = 49–234) and variable Nb/Ta ratios (Nb/Ta = 2–30). The Si-poor carbonatites resemble the Si-rich carbonatites and the white syenites with elevated REE contents in apatite equilibrium melts compared to clinopyroxene. However, apatite equilibrium melt in Si-poor carbonatite shows a majority of subchondritic values (Nb/Ta