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International audience; The presence of nematodes was investigated in 84 small mammals belonging to 10 species living in arid wildhabitats from Central Tunisia. Hosts were infected with a total of 7 species of nematodes. The dominant parasite species wasGongylonema neoplasticum, which was found in the stomach of 7 host species with prevalences varying from 15.4% inGerbillus campestris to 50% in Meriones shawi. Several nematodes, such as Syphacia obvelata, Acanthocheilonema viteae,Trichuris gerbilli, and G. neoplasticum, are potential zoonotic parasites. These latter species were collected from M. shawi,Meriones libycus, Mus musculus, Mus spretus, Rattus rattus, G. campestris, Psammomys obesus, and Ctenodactylus goundi,raising concern that these rodents and their associated rodent-borne helminths could be of potential concern for public healthin this region.

Changes in the planktonic cyanobacteria structure, composition and diversity were followed over three consecutive years (2005–2006–2007) in the Gulf of Gabes (Eastern Mediterranean Sea, Tunisia). Cyanobacteria abundances, biomasses and cell lengths were measured together with selected environmental variables (pH, salinity, temperature and nutrients). The space and time variations of the cyanobacteria in relation to the environmental factors showed a close relationship between these plankton communities and the hydrographic structure of the water column. Cyanobacteria developed over semi-mixed conditions (May–June 2006) and during the thermal stratification (July 2005). The cyanobacterial abundance and biomass was evident between 20 and 35 m in inshore stations and between 20 and 25 m in deeper stations during the semi-mixing conditions and stratification. This thermocline level coincided with the euphotic layer (21.85 ± 3.76 m) allowing access of light radiation. The cyanobacteria bloom occurred during May–June 2006 when the N/P ratio (2-fixing) cyanobacteria such as Anabaena sp., Chroococcus sp., Trichodesmium erythraeum, Spirulina sp. and Spirulina subsalsa and non-diazotrophic cyanobacteria such as Pseudoanabaena sp. and Microcystis display a great flexibility in the N sources which allow formation of blooms.

International audience; The present study analyses the spatio-temporal variability of the macrozoobenthos from the intertidal zone of the Kneiss Islands (Gulf of Gabès, Tunisia). Samples were collected once from 34 stations, while seasonal variations were studied by sampling four times at 12 stations over the period 2013-2014. A total of 159 macrobenthos taxa associated with intertidal Zostera noltei beds are identified from the 34 stations, with a taxonomic dominance of crustaceans (32%), molluscs (29%) and annelids (27%). Abundance varies from 9244 to 36,844 ind・m−2 with a mean value of 14,346 ind・m−2. Analysis of the trophic structure shows that the majority of stations are strongly represented by carnivores (41%), followed by the non-selective deposit feeders (16%). Cluster analysis and multidimensional scaling allow identification of three main benthic assemblages based on species abundance, corresponding to different sediment types and organic matter contents. The seasonal variability in abundance, diversity and community structure is mainly due to spring and summer recruitment. The biotic indices (i.e. AMBI, BO2A and BENTIX) show that the intertidal area of Kneiss Islands exhibits a good ecological status.

International audience; The Gulf of Gabès in southern Tunisia shows the highest tidal ranges of the Mediterranean Sea. During spring tides, the very large intertidal sand and mudflat zone is exploited for clam harvesting, mainly targeted on the species Ruditapes spp. mainly Ruditapes decussatus by Linnaeus in 1758. To assess the short-term impact of clam harvesting on the intertidal macrobenthos of the Kneiss Islands mudflats, a control-impact study was set up in September and December 2013 using a BACI (Before-After-Control-Impact) design, with a control station and eight stations fished for clams. Significant decreases in total macrofauna, benthic polychaetes (mainly Nephtyidae, Eunicidae, Spionidae, Maldanidae, Sabellidae and Cirratulidae) and R. decussatus were observed from before to after the harvesting initiated. In the future, it would be very important to control this human activity, due to its negative impact on the surrounding macrofauna, which represent essential prey for fishes and birds living in this protected area.

The Kneiss islands, located in the Gulf of Gabès (Southeastern Tunisia), represent a site of international interest in terms of their ornithological diversity (Important Bird Area, SPAMI and Ramsar Site) and are heavily exploited for clams and fish resources. In an effort to assess the ecological status of the intertidal ecosystem, and to facilitate management and conservation of the resources, an ecological survey of the macrobenthic component was carried out from January to March 2012. This study involved identifying the benthic fauna and assessing the spatial distribution on the southern unperturbed Zostera noltei mudflats by human activities. A total of 102 macrobenthos taxa is identified at 19 stations with a predominance of crustaceans (37%), polychaetes (27%) and molluscs (23%). The AMBI index shows that the area has a good ecological status. Cluster Analysis and Multidimensional scaling identify three benthic assemblages on the basis of their faunal similarity in relation to sediment types and organic matter contents., RésDistribution spatiale et abondance de la macrofaune intertidale des îles Kneiss (Golfe de Gabès, Tunisie). La distribution spatiale et l'abondance des communautés macrobenthiques des îles Kneiss (Golfe de Gabès, Tunisie) ont été étudiées. Par leur diversité ornithologique, les îles Kneiss présentent un intérêt international (Site Ramsar, ZICO, ASPIM), mais l'activité de collecte de la palourde (Ruditapes decussatus) et la pêche intensive au chalut benthique ont conduit à la surexploitation des ressources. Pour évaluer l'état écologique de cet écosystème et faciliter la gestion et la conservation des ressources, une étude écologique de la composante benthique a été réalisée. La macrofaune benthique des vasières des îles Kneiss a été étudiée de janvier à mars 2012 dans une zone d'herbier de Zostera noltei peu perturbée par des activités humaines. Un total de 102 taxa de macrobenthos a été identifié dans 19 stations, avec une dominance de crustacés Amphipodes (37%), des Annélides Polychètes (27%) et des Mollusques (23%). L'indice biotique AMBI a montré que la région est en bon état écologique. Trois assemblages benthiques ont été identifiés par la classification ascendante hiérarchique et le positionnement multidimensionnel sur la base de leur spécificité faunistique, le type de sédiments et les contenus en matière organique.

International audience; Pseudorhabdosynochus regius n. sp. is described from the gills of the mottled grouper Mycteroperca rubra caught off Senegal, Tunisia and Libya (type-locality: off Dakar, Senegal). The species is distinguished from its congeners by the structure of its sclerotised vagina (length 26–35 μm), which exhibits a trumpet in continuity with the primary canal, a straight primary canal, and primary and secondary chambers included in a common sclerotised mass along the primary canal. The species is also characterised by small squamodiscs (length 20–40 μm) with 10–11 rows of rodlets. Its closest relatives (based on the structure of the sclerotised vagina) are species mostly found in the Mediterranean Sea and parasites on species of Mycteroperca. A second species of Pseudorhabdosynochus Yamaguti, 1958 is reported from the same host and localities but not described. A list of diplectanids from groupers in the Mediterranean Sea is provided. We point out that a recent article was not compliant with the new Article 8.5.3 of the International Code of Zoological Nomenclature; for this reason, three species, P. nhatrangensis Dang, Bristow, Schander & Berland, 2013, P. vietnamensis Dang et al., 2013 and P. brunei Dang et al., 2013, are invalid.; Pseudorhabdosynochus regius n. sp. est décrit des branchies du mérou royal Mycteroperca rubra pêché au Sénégal, en Tunisie et en Libye (localité-type: au large de Dakar, Sénégal). L’espèce se distingue de ses congénères par la structure de son vagin sclérifié (longueur 26-35 μm), qui présente une trompette en continuité avec le canal primaire, un canal primaire droit, et des chambres primaire et secondaire incluses dans une masse sclérifiée commune le long du canal primaire. L’espèce est également caractérisée par de petits squamodisques (longueur 20-40 μm) avec 10-11 rangées de bâtonnets. Ses plus proches parents (sur la base de la structure du vagin sclérifié) sont pour la plupart des espèces trouvées dans la mer Méditerranée et parasites sur des espèces de Mycteroperca. Une seconde espèce de Pseudorhabdosynochus Yamaguti, 1958 est signalée dans le même hôte et même localités mais non décrite. Une liste des Diplectanidae de mérous en mer Méditerranée est fournie. Nous signalons qu’un article récent n’était pas conforme avec le nouvel article 8.5.3 du Code International de Nomenclature Zoologique; pour cette raison, trois espèces, P. nhatrangensis Dang, Bristow, Schander & Berland, 2013, P. vietnamensis Dang et al., 2013 et P. brunei Dang et al., 2013 ne sont pas valides.

The spatial and temporal distribution, abundance and assemblage structure of polychaete communities in the Kneiss Islands (central Mediterranean Sea) was studied at 42 stations selected among seagrass Zostera (Zosterella) noltei Hornemann meadows and unvegetated habitats sampled from April 2014 to January 2015. The Kneiss Islands represent a site of international interest in terms of their ornithological diversity (Important Bird Area, Ramsar Site and SPAMI). A total of 18,026 individuals and 92 species of polychaetes belonging to 25 families were identified. Analysis of the trophic structure reveals that the majority of stations are strongly dominated by deposit feeders (51.2%), followed by carnivores (34.8%) and suspension feeders (14%). Polychaete diversity and abundance were higher on the vegetated stations. Four polychaete assemblages are identified using MDS analysis. The distribution of polychaete assemblages are influenced by edaphic factors, particularly sediment structure and organic matter content. Seasonal variations of the polychaete community patterns at 20 stations show a maximum abundance and diversity during spring and summer and a minimum during winter. Seasonal fluctuations follow the seasonal variations of the environmental factors such as temperature and salinity, and correspond also to the lifestyle of the dominant species.

International audience; A thiophene bearing a cyclopropyl ketone group at C2 was successfully employed in palladium-catalysed direct arylation. The reaction proceeds regioselectively at C5 without decomposition of the cyclopropyl ketone substituent. These couplings were performed employing as little as 0.5 mol% of ligand-free Pd(OAc)2 catalyst with electron-deficient aryl bromides. A wide variety of functional groups on the aryl bromide such as nitrile, nitro, acetyl, formyl, benzoyl, ester, trifluoromethyl, fluoro or methoxy was tolerated. © 2013 Elsevier Science. All rights reserved.

International audience; In this work we propose an approximate numerical method for pricing of options for the constant elasticity of variance (CEV) diffusion model. We prove firstly the existence and uniqueness of the solution in weighted Sobolev space, and then we propose the finite element method and finite difference method to solve the considered problem. Therefore, we compare the obtained results by the two approaches, with those given by the Monte Carlo method in Broadie-Kaya [6], using two simulation techniques : the exact method and the Euler discretization. A comparative numerical study is done using some values of the coefficient of elasticity

This paper describes the realization and characterization of $${\text{La}}_{0.8}{\text{Pb}}_{0.1}{\text{Ca}}_{0.1}{\text{Fe}}_{1-x}{\text{Co}}_{x}{\text{O}}_{3}$$ gas-based sensors. $${\text{La}}_{0.8}{\text{Pb}}_{0.1}{\text{Ca}}_{0.1}{\text{Fe}}_{1-x}{\text{Co}}_{x}{\text{O}}_{3}$$ $$(0.00\le x\le 0.20)$$ thin films are prepared using the drop-coating method over a $${\text{Si}}/{\text{SiO}}_{2}$$ substrate with inter-digitated $${\text{Pt}}$$ -electrodes. The sensors, thus, produced exhibit a good sensitivity to ozone at low concentration. The substitution of iron atoms by cobalt ones increases the sensor responses “S,” from 1.716 for $$x = 0.00$$ to 6.584 to $$x = 0.20$$ for an ozone concentration equal to $$400\,{\text{ppb}}$$ . In addition, the substitution of iron by cobalt induces a decrease in the sensor-operating temperature from $$270\,^\circ{\text{C}}$$ for the parent compound $$(x = 0.00)$$ to $$170\,^\circ{\text{C}}$$ for $$x = 0.20$$ .

For a natural exponential family (NEF), one can associate in a natural way two standard families of conjugate priors, one on the natural parameter and the other on the mean parameter. These families of conjugate priors have been used to establish some remarkable properties and characterization results of the quadratic NEF's. In the present paper, we show that for a NEF, we can associate a class of NEF's, and for each one of these NEF's, we define a family of conjugate priors on the natural parameter and a family of conjugate priors on the mean parameter which are different of the standard ones. These families are then used to extend to the Letac-Mora class of real cubic natural exponential families the properties and characterization results related to the Bayesian theory established for the quadratic natural exponential families.

Les documents électroniques (rapports, notes, articles...) évoluent et présentent des contenus de plus en plus riches et complexes. Ainsi, ils font l'objet de changements rapides a priori imprédictibles. Se pose alors le problème de détection de ces changements. En effet, il faut détecter les changements induits par les évolutions, en comparant les anciennes et les nouvelles versions des documents et en évaluant la similarité entre ces versions. Le besoin de pouvoir versionner et analyser ces documents augmente constamment, il convient donc de disposer des outils adéquats. Les entrepôts de documents présentent une solution d'intégration et d'historisation de ces documents. L'adjonction de l'aspect temporel dans ces entrepôts vise à proposer des solutions pour le versionnement des documents. L'objectif de cet article est de présenter et d'analyser l'état de l'art des travaux de recherche menés dans les entrepôts de documents XML. En particulier, il présente l'intégration de la notion du temps dans ce type d'entrepôts.

International audience; A Data Warehouse (DW) stores data coming from heterogeneous data sources at decisional ends. To query the stored data, there are specific operators, called OLAP operators which facilitate the analysis and the visualization of data. However, these operators, as they are defined in classic DW context, do not allow querying a MultiVersion Data Warehouse (MVDW) which takes account of the evolutions which can affect the members of dimension and/or the DW schema components. In order to appropriately analyze multiversion data, an extension to the traditional OLAP operator is required. In this paper, we propose a MVDW query language called MVOLAP. To this end, we extend the classic OLAP operators to adapt them to the MVDW context.

International audience; En Tunisie, le logement social a toujours été avancé comme une préoccupation majeure des différentes politiques d’habitat adoptées depuis l’indépendance. Les responsables développent souvent un discours sur la réussite du modèle tunisien en matière d’habitat social. Cependant, l’examen de l’évolution de ces politiques et des programmes réalisés fait apparaître les limites et les insuffisances du secteur logement social sous le monopole de l’Etat.Après un effort de construction durant les premières années succédant l’indépendance, on a assisté à une tendance inéluctable de désengagement de l’État de la production du logement social. En effet, les politiques d’habitat qui se sont succédé ont été en grande partie orientées vers la satisfaction des besoins des classes moyennes en négligeant la demande des couches les plus vulnérables. Le problème du logement social est identifié comme celui d’un désajustement entre l’offre et la demande.A travers une rétrospective critique des politiques d’habitat et une restitution détaillée de leurs évolutions, cette contribution tente d’appréhender les limites des programmes publics de logement social tout en cherchant à identifier les logiques gestionnaires dominantes auxquelles ces politiques renvoient ainsi que leurs conséquences socio spatiales.

International audience; This paper describes our efforts to extend the PARSEME framework to Modern Standard Arabic. The applicability of the PARSEME guidelines was tested by measuring the inter-annotator agreement in the early annotation stage. A subset of 1,062 sentences from the Prague Arabic Dependency Treebank PADT was selected and annotated by two Arabic native speakers independently. Following their annotations, a new Arabic corpus with over 1,250 annotated VMWEs has been built. This corpus already exceeds the smallest corpora of the PARSEME suite, and enables first observations. We discuss our annotation guideline schema that shows full MWE annotation is realizable in Arabic where we get good inter-annotator agreement.

We prove the following: Let G and $$G'$$ G ′ be two graphs on the same set V of v vertices, and let k be an integer, $$4\le k\le v-4$$ 4 ≤ k ≤ v - 4 . If for all k-element subsets K of V, the induced subgraphs $$G_{\restriction K}$$ G ↾ K and $$G'_{\restriction K}$$ G ↾ K ′ have the same numbers of 3-homogeneous subsets, the same numbers of $$P_4$$ P 4 ’s, and the same numbers of claws or co-claws, then $$G'$$ G ′ is equal to G or to the complement $$\overline{G}$$ G ¯ of G. We give also a similar result whenever the same numbers are modulo a prime.

Let G=(V,E) be a graph. The complement of G is the graph G¯:=(V,[V]2 \ E) where [V]2 is the set of pairs {x,y} of distinct elements of V. If K is a subset of V, the restriction of G to K is the graph G↾K:=(K,[K]2∩E). We prove that if G=(V,E) is a graph and k is an integer, 2 ≤ k ≤ v−2, then there is a k -element subset K of V such that e(G¯↾K)≠e(G↾K), moreover the condition k ≤ v−2 is optimal. We also study the case e(G¯↾K) ≢ e(G↾K)(mod p) where p is a prime number. Following a question from M.Pouzet, we show this: Let G=(V,E) be a graph with v vertices. If e(G) ≠ e(G¯) (resp. e(G)=e(G¯)) then there is an increasing family (Hn)2≤n≤v (resp. (Hn)2≤n≤v−2) of n -element subsets Hn of V such that e(G↾Hn)≠ e(G¯↾Hn) for all n. Similarly if e(G) ≢ e(G¯) (mod p) where p is a prime number, p>v−2, then there is an increasing family (Hn)2≤n≤v of n -element subsets Hn of V such that e(G↾Hn) ≢ e(G¯↾Hn)(mod p) for all integer n∈{2,3,…,v}.

This article proposes a crisp-based approach for representing and reasoning about concepts evolving in time and of their properties in terms of qualitative relations (e.g., “before”) in addition to quantitative ones, time intervals and points. It is not only suitable to handle precise time intervals and points, but also imprecise ones. It extends the 4D-fluents approach with crisp components to represent handed data. It also extends the Allen's interval algebra. This extension allows reasoning about imprecise time intervals. Compared to related work, it is based on crisp set theory. These relations preserve many properties of the original algebra. Their definitions are adapted to allow relating a time interval and a time point, and two time points. All relations can be used for temporal reasoning by means of transitivity tables. Finally, it proposes a crisp ontology that based on the extended Allen's algebra instantiates the 4D-fluents-based representation.

International audience; In this paper, we propose an ontology-based approach for representing and reasoning about certain and uncertain temporal data. Ithandles temporal data in terms of quantitative time intervals and points and the qualitative relations between them (e.g., “before”). Itincludes three parts.(1)We extend the 4D-fluents approach with certain ontological components to represent the handled temporaldata in OWL 2.(2)We extend the Allen’s interval algebra to reason about certain and uncertain time intervals. We adapt theserelations to allow relating a time interval and a time point, and two time points. All relations can be used for temporal reasoning bymeans of transitivity tables.(3)The extended Allen’s algebra instantiates the 4D-fluents-based representation. Inferences are basedon SWRL rules. Based on this ontology, a prototype is implemented and integrated into an ontology-based memory prosthesis forAlzheimer’s patients to handle certain and uncertain temporal data inputs.

A techno-economic analysis of production of bio-oil from catalytic pyrolysis of olive mill wastewater sludge has been performed with two different cooling schemes. The two configurations differ in the manner how the bio-oil vapors are quenched. In scheme-1, a vapor compression refrigeration machine is utilized for condensation of bio-oil vapors while in scheme-2, the vapor compression refrigeration machine is replaced by absorption refrigeration machine. The two schemes are modelled in Aspen Plus which provides mass and energy balances. For techno-economic analysis, Aspen process economic analyzer is employed. The model is first validated against experimental data from lab scale and then upscaled to an industrial scale of 100 tonnes/day wet biomass (93 tonnes/day dry biomass). Results show that the model with absorption refrigeration machine (scheme-2) has a slightly better process efficiency and a lower MFSP compared to the model with compression refrigeration machine (scheme-1). Total anticipated capital investment expenses for scheme-1 and scheme-2, comprising plant fixed capital investment (FCI), start-up, working capital, and interest, are expected to be €22.1 M and €17.5 M, respectively. The equipment costs are based on first quarter of 2021 and the economic life of the project is 20 years. Monte Carlo sensitivity analyses showed that the bio-oil MFSP is most vulnerable to discounted cash flow, income tax and bio-oil yield. The production cost of bio-oil varies between €2.16/GGE and €6.19/GGE for scheme-1 and €1.78/GGE and €5.01/GGE for scheme-2 when cost parameters are varied within an industrially relevant range. The findings support the viability of producing bio-oil by catalytic fast pyrolysis on a commercial scale.

Edited by Jaroslaw Watrobski, Wojciech Salabun, Carlos Toro, Cecilia Zanni-Merk, Robert J. Howlett, Lakhmi C. Jain; International audience; Nowadays, special attention is directed to trust issues in the Decentralized Online Social Network (DOSN). In a distributed system for social networking, interactions and collaborations can be unreliable because some users resort to malicious behaviors in order to increase their trust values in the network to be chosen later by others, and launch trust-related attacks. In this unreliable situation, users will not be able to estimate the trustworthiness of the received social services’ list of recommendations. Hence, a trust management model becomes a necessity in order to overcome its trust-related attacks and to recommend trustworthy social services. In this respect, we propose a new trust management model that helps prevent trust-related attacks in order to ensure a reliable environment. Towards this end, our suggested model implements a new technology, called blockchain. Based on the studied trust-related attacks, we intend to add logical security to blockchain since this technology takes into account only the physical security. Evaluation values show the effectiveness of our model.

Data curation deals with managing the data by applying different tasks such as extraction, enrichment, cleaning to fit the purpose of use. Indeed, nowadays, there is an increasing need to implement such tasks in the big data era to maintain data management. Big data is involved in decision processes to perform analysis, visualization, prediction, etc. Thus, there is a dependency between the generated outcomes and the input data of such a process. Therefore, decision process features (e.g., decision context, user constraints, and requirements) need to be taken into account during the data management process, including the data curation phase. Although the proposed curation approaches in the literature are diverse, most of them are static and do not consider the decision process features. Moreover, most of the proposals are dedicated to curating a specific data source format (e.g., structured/unstructured data source). To overcome these limitations, we propose a new approach ACUSEC (Adaptive CUration SErvice Composition) that ensures adaptive curation services composition by considering different features: the source type, the user constraints and preferences, and the decision context. To do so, we rely on AI and machine learning mechanisms such as reinforcement learning. Following the approach's definition, we conducted experiments that show encouraging results in overall execution time and adaptation to the above features.

The computer science community is paying more and more attention to data due to its crucial role in performing analysis and prediction. Researchers have proposed many data containers such as files, databases, data warehouses, cloud systems, and recently data lakes in the last decade. The latter enables holding data in its native format, making it suitable for performing massive data prediction, particularly for real-time application development. Although data lake is well adopted in the computer science industry, its acceptance by the research community is still in its infancy stage. This paper sheds light on existing works for performing analysis and predictions on data placed in data lakes. Our study reveals the necessary data management steps, which need to be followed in a decision process, and the requirements to be respected, namely curation, quality evaluation, privacy-preservation, and prediction. This study aims to categorize and analyze proposals related to each step mentioned above.

International audience; In this paper, we propose an approach to handling uncertain time intervals and related qualitative relations, based on possibility theory. Four contributions are included in this approach. (1) Representing uncertain time intervals and related qualitative relations by extending the 4D-fluents approach with new ontological components. (2) Reasoning about uncertain time intervals by extending the Allen’s interval algebra. The resulting interval relations preserve the good properties of the original algebra. (3) Proposing an OWL 2 possibilistic temporal ontology based on 4D-fluents approach extension and Allen’s interval algebra extension. The proposed qualitative temporal relations are inferred via a set of SWRL rules. We validate our work by implementing a prototype based on this ontology. (4) Applying our work to PersonLink ontology and comparing the obtained results with our previous works.

International audience; We provide constructive versions of Hilbert's syzygy theorem for Z and Z/nZ following Schreyer's method. Moreover, we extend these results to arbitrary coherent strict Bézout rings with a divisibility test for the case of finitely generated modules whose module of leading terms is finitely generated.

This work presents the characterisation and comparison of daytime and nighttime mountain breezes observed at three sites through the analysis of tower data. The sites are located: (i) in the foothills of the Guadarrama Mountains in Spain, (ii) on a plateau adjacent to the Pyrenees in France, and (iii) in the Salt Lake Valley (SLV) in the southwest of the United States. The thermally-driven winds are detected through a systematic algorithm which considers both synoptic and local meteorological conditions. The characteristics of the mountain breezes depend on the scale of the breeze at each site. Nighttime events are associated with stronger wind speeds at the two sites located farther away from the mountains due to larger-scale phenomena (valley winds and mountain-plain winds). The arrival of both nighttime and daytime flows to the sites are observed approximately when the buoyancy heat flux changes sign, being a few hours delayed at the sites farther from the mountains. In addition, the impacts of these breezes on CO2 mixing ratios are analysed. The characteristic increase of CO2 mixing ratio observed during the evening transition takes place approximately when the nocturnal breeze arrives at the site. Nonetheless, both processes are not always simultaneous, indicating that CO2 advection is not the main mechanism controlling the drastic CO2 increase. An analogous result is obtained for the CO2 decrease at the morning transition. However, we have found that the CO2 mixing ratio is sensitive to wind direction (horizontal advection) in highly heterogeneous areas like the SLV, where CO2 emissions from the nearby city centre play an important role. Finally, a clear relationship is found between the CO2 mixing ratio and near-surface turbulence at night. Maximum CO2 mixing ratios are found for specific turbulence thresholds, which depend on the height of the CO2 sensor. Conditions associated with both stronger and weaker turbulence levels lead to reduced CO2 mixing ratios at the local measurement height due to excessive and ineffective mixing, respectively.

International audience; Blockchain technology enables several untrustworthy parties to execute inter-organizational business processes in a tamper-proof manner. Existing approaches are based on smart contract code generation. Although the smart contract immutability guarantees that the process model is followed by each participant, any change in the process model makes the existing process instance smart contract not compliant with the process model and therefore, the deployment of a new smart contract becomes a requirement. In this paper, we propose CoBuP, a decentralized Collaborative Business Process execution architecture using blockchain. To address the inflexibility issue, this paper presents an interpreter of BPMN process models, supporting the instantiating, execution, monitoring of process instances. For this reason, one generic smart contract is deployed once, which helps generate a process instance, create BPMN elements by invoking the process instance predefined functions, and dynamically update the adaptation of a process at run time. For validation purposes, two use cases have permitted to carry out different experiments that demonstrate the technical feasibility of our approach. The obtained results of the experimental evaluation shows that our approach cost is similar or lower than that of the existing approaches.

International audience; The insurance industry is heavily dependent on several processes executed among multiple entities, such as insurer, insured, and third-party services. The increasingly competitive environment is pushing insurance companies to use advanced technologies to address multiple challenges, namely lack of trust, lack of transparency, and economic instability. To this end, blockchain is used as an emerging technology that enables transparent and secure data storage and transmission. In this paper, we propose CioSy, a collaborative blockchain-based insurance system for monitoring and processing the insurance transactions. To the best of our knowledge, the existing approaches do not consider collaborative insurance to achieve an automated, transparent, and tamper-proof solution. CioSy aims at automating the insurance policy processing, claim handling, and payment using smart contracts. For validation purposes, an experimental prototype is developed on Ethereum blockchain. Our experimental results show that the proposed approach is both feasible and economical in terms of time and cost.

Wildfire prediction from Earth Observation (EO) data has gained much attention in the past years, through the development of connected sensors and weather satellites. Nowadays, it is possible to extract knowledge from collected EO data and to learn from this knowledge without human intervention to trigger wildfire alerts. However, exploiting knowledge extracted from multiple EO data sources at run-time and predicting wildfire raise multiple challenges. One major challenge is to provide dynamic construction of service composition plans, according to the data obtained from sensors. In this paper, we present a knowledge-driven Machine Learning approach that relies on historical data related to wildfire observations to guide the collection of EO data and to automatically and dynamically compose services for triggering wildfire alerts.

Temporal data given by Alzheimer's patients are mostly uncertain. Many approaches have been proposed to handle certain temporal data and lack uncertain ones. This paper proposes an approach to represent and reason about quantitative time intervals and points and qualitative relations between them. It is suitable to handle certain and uncertain temporal data. It includes three parts. (1) The authors extend the 4D-fluents approach with certain components to represent certain and uncertain temporal data. (2) They extend the Allen's interval algebra to reason about certain and uncertain time intervals. They adapt these relations to relate a time interval and a time point, and two time points. All relations can be used for temporal reasoning by means of transitivity tables. (3) They propose a certain ontology based on the extensions. A prototype is implemented and integrated into an ontology-based memory prosthesis for Alzheimer's patients to handle uncertain data inputs. The evaluation proves the usefulness of the approach as all the inferences are well established and the precision results are promising.

International audience; The rapid development of blockchain technology has influenced several fields, including financial, healthcare, and supply chain systems. Recently, this technology has also been applied in education thanks to its unique features, including decentralization, trustworthiness, and security. Despite the bright side of blockchain, several concerns continue to undermine its adoption in education, such as legal, immutability, and scalability issues. Thus, a comprehensive survey about blockchain adoption in education deems necessary. This paper is a systematic literature review of blockchain applications in the education field. To do so, and after retrieving scientific publications on the topic, we classify the outcomes according to several categories. In this paper, we focus on two major themes: educational applications and benefits of blockchain integration. We combine the themes, then express and analyze the results as bubble charts. We analyze the proposed solutions in terms of the blockchain-based applications that have been developed for educational purposes and the benefits that the blockchain technology could bring to the education field. Finally, we describe some research gaps that need to be addressed and educational areas that could be explored for future research of blockchain adoption in education.

Data analytics based on the produced data from the Internet of Things (IoT) devices is expected to improve the individuals’ quality of life. However, ensuring security and privacy in the IoT data aggregation process is a non-trivial task. Generally, the IoT data aggregation process is based on centralized servers. Yet, in the case of distributed approaches, it is difficult to coordinate several untrustworthy parties. Fortunately, the blockchain may provide decentralization while overcoming the trust problem. Consequently, blockchain-based IoT data aggregation may become a reasonable choice for the design of a privacy-preserving system. To this end, we propose PrivDA, a Privacy-preserving IoT Data Aggregation scheme based on the blockchain and homomorphic encryption technologies. In the proposed system, each data consumer can create a smart contract and publish both terms of service and requested IoT data. Thus, the smart contract puts together into one group potential data producers that can answer the consumer’s request and chooses one aggregator, the role of which is to compute the group requested result using homomorphic computations. Therefore, group-level aggregation obfuscates IoT data, which complicates sensitive information inference from a single IoT device. Finally, we deploy the proposal on a private Ethereum blockchain and give the performance evaluation.

International audience; We consider in this paper a perturbation of the standard semilinear heat equation by a term involving the space derivative and a non-local term. We prove the existence of a blow-up solution, and give its blow-up profile. Our method relies on the two-step method: we first linearize the equation (in similarity variables) around the expected profile, then we use a topological argument to controle the positive directions of the spectrum.

International audience; In recent years, mass retailing has undergone an important and rapid evolution, despite a generally unstable political and economic framework. We were witnessing an evolution and remodeling of the large retailers. In fact, large-scale retailers continue to win new shares in the retail market. In addition, it knows the introduction of new forms (Hard discount) and targeted new locations (local trade). This new strategy is adopted by "Aziza", a new hard-discount local food retailer, which appeared in 2014. It belongs to the Slama group active in the agri-food sector via GIAS brands (Goldina, Nejma), Ice Cream (Nassim), Hightech (MB). The strategy of the new chain is to locate near the most populated areas including the popular neighborhoods. This brand now has more than 170 stores spread mainly in large and medium-sized cities.

Recently, special attention has been given to the study of dynamical systems defined on one-dimensional spaces, for example arcs, circles, graphs, dendrites and local dendrites. The interest of studying the dynamics of functions defined on these spaces is due: Firstly, dendrites are examples of Julia sets in complex dynamics. Second, (local) dendrites are continuous Peanians (connected, locally connected compact space) in continuum theory. The objectif of this thesis is to find a characterization of dynamical equicontinuous systems defined on a compact metric space. As an application of this result we have proved necessary and sufficient conditions on equicontinuity for a dynamic system defined on a particular local dendrite and therefore it is a generalization of the theorem 2.8., Récemment, une attention particulière a été accordée à l’étude des systèmes dynamiques défini sur des espaces unidimensionnels, par exemple les arcs, les cercles, les graphes, les dendrites et les dendrites locales. L’intérêt d’étudier la dynamique des fonctions définies sur ces espaces est dû à: Premièrement, les dendrites sont des exemples de l’ensemble de Julia dans la dynamique complexe. Deuxièmement, les dendrites (locales) sont des Péaniens continus (espace compact, connexe, localement connexe) dans la théorie du continus. L’objectif de cette thèse est de trouver une caractérisation du système dynamique équicontinu défini sur un espace métrique compact. Comme application de ce résultat, on a démontré des conditions nécessaires et suffisantes à l’équicontinuité pour un système dynamique défini sur une dendrite locale particulière et donc c’est une généralisation du théorème 2.8.

The increasing use of 3D models in many areas lead us to think about the impact of the different distortions that can affect the 3D object during the rendering process. These deformations are usually evaluated using geometric metrics, which have not a good correlation with human judgment, while the visual perceptual quality of 3D models is necessary. In this context, a new full-reference metric denoted LWRMS is defined in this work. It can predict the distortion score between the original object and its damaged version without taking into account the constraint of connectivity. The proposed metric is defined in order to get a good correlation with the human visual perception coming from a subjective measurement. The numerical experiments are carried out on a known database LIRIS/EPFL General-Purpose database. The quantitative results show a good performance of the proposed metric in comparison with methods from the literature.

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International audience; We continue the investigation, started in [J. Stat. Phys. 166, 926-1015 (2017)], of a network of harmonic oscillators driven out of thermal equilibrium by heat reservoirs. We study the statistics of the fluctuations of the heat fluxes flowing between the network and the reservoirs in the nonequilibrium steady state and in the large time limit. We prove a large deviation principle for these fluctuations and derive the fluctuation relation satisfied by the associated rate function.

International audience; Forcings and mechanisms underlying Holocene climate variability still remain poorly. This work review already published paleoclimatic time series and proposes an alternative way to compare them using spectral analysis. Such an approach may emphasize joint features between different signals and lead us closer to the causes of climate changes.Ten paleoclimatic proxy records from 5 sequences from the Gulf of Lions and surrounding areas were compiled. These paleoclimate time-series were supplemented with proxies of the North Atlantic Oscillations (NAO), El Niño–Southern Oscillations (ENSO) and the Intertropical Convergence Zone (ITCZ) variability. A comparison of their frequency content is proposed using wavelet analysis for unevenly sampled time series. A new algorithm is used in order to propagate the age model errors within wavelet power spectra.Three main groups of shared features specific to the Mid- and Late Holocene (after 7000 yrs cal BP) can be defined on the basis of the results of these analyses, an Atlantic cyclic period, solar cyclic periods and tropical cyclic periods. The Atlantic cyclic period is probably related to fluctuations of the Atlantic thermohaline circulation which would induce changes in the storm track extension and position thereby impacting upon precipitation and storminess over a millennial scale. The centennial scale solar variability might induce a NAO-like variability of the atmospheric circulation thereby influencing storminess in Western Europe and Mediterranean. Finally, tropical cyclic periods are possibly registered in of the Gulf of Lions and Atlantic climate proxies, potentially highlighting the influence of ENSO variability over the western Mediterranean.

39 pages, 8 figures, 3 tables; In this work, we develop and study a discontinuous Galerkin (DG) method to approximate the solution of 1D nonlinear wave equations. We show that the numerical scheme is consistent, stable and convergent if a nonuniform time mesh is considered. We also investigate the blow-up phenomena and we prove that the numerical blow-up time converges toward the theoretical one. The validity of our results is confirmed throughout several numerical examples and benchmarks.

In this study, the authors present a new approach to segment and classify moving objects in video sequences by combining an unsupervised anomaly discovery framework called DeepSphere and generative adversarial networks. The proposed deep detector classifier employs and validates DeepSphere, which aims mainly to identify the anomalous cases in the spatial and temporal context in order to perform foreground objects segmentation. For post-processing, some morphological operations are considered to better segment and extract the desired objects. Finally, they take advantage of the power of generative models, which recognise the problem of semi-supervised learning as a specific missing data imputation task in order to classify the segmented objects. They evaluate the method with multiple datasets and the results confirm the effectiveness of the proposed approach, which achieves superior performance over the state-of-the-art methods having the capabilities of segmenting and classifying moving objects from videos surveillance.

International audience; Recommendation Systems have gained the intention of many researchers due to the growth of the business of personalizing, sorting and suggesting products to customers. Most of rating prediction in recommendation systems are based on customer preferences or on the historical behavior of similar customers. The similarity between customers is generally measured by the number of times customers liked or disliked the same item. Given the huge number and the variety of items, many customers cannot be considered as similar, as they did not evaluate the same items, even if they have similar tastes. This paper presents a new method of rating prediction in recommendation systems. The proposed method starts by identifying the taste directions or the interest centers based on the users' demographic information combined with their previous evaluations. Thus, it uses the Principal Component Analysis (PCA) to retrieve the major taste orientations. According to these orientations, user groups are created. Then, for each group, it generates a prediction model, that will be used to predict unknown rates of users within the corresponding group. In order to assess the accuracy of the proposed method, we compare its results with four baseline methods, namely: RegSVD, BiasedMF, SVD++ and MudRecS. Results prove that the proposed algorithm is more accurate than the base-line algorithms.

International audience; First description of NDM-1-positive Klebsiella pneumoniae in the Tunisian community Sir, Multidrug-resistant bacteria, especially carbapenemase-producing Enterobacteriaceae, are a major public health-threat worldwide. As part of a collaborative monitoring programme, our laboratory at the University of Bordeaux has received a collection of multidrug-resistant bacterial strains to further characterise their β-lactamase content. They were sent from private Tunisian diagnostic laboratories and were collected from community patients suffering from urinary tract infection. In this context, multidrug-resistant isolate 18TA was collected in January 2018 in Sfax region from the urine of a 45-year old female with no previous hospitalisation during the preceding month and no history of recent foreign travel. Strain 18TA had been initially classified as Enterobacter spp. by biochemical tests (API 10S gallery). Following matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF/MS) (Bruker Daltonics) and confirmation by PCR amplification and sequencing of 16S rDNA, strain 18TA was re-identified as Klebsiella pneumoniae. Multilocus sequence typing (MLST) (http:// bigsdb.pasteur.fr/klebsiella/klebsiella.html) indicated that strain 18TA belonged to Sequence Type (ST), ST147. Minimum inhibitory concentrations (MICs) of various anti-microbials were determined using a BD Phoenix TM 100 automated system (BD Diagnostic Systems, Le Pont-de-Claix, France) and the results were interpreted using BD EpiCenter TM software (BD Diagnostic Systems). The MICs for ciprofloxacin and colistin were also determined by the broth microdilution method according to European Committee on Antimicrobial Susceptibility Testing 2019 guidelines (https://www.sfm-microbiologie.org/2019/05/06/ casfm-eucast-2019-v2/). Strain 18TA was resistant to all tested β-lactams, including carbapenems (Table 1). The strain was also resistant to gentamicin, tobramycin, quinolones (nalidixic acid), fluoroquinolones (cipro-floxacin) and trimethoprim/sulfamethoxazole (SXT) and showed decreased susceptibility to tigecycline (MIC = 2 mg/mL). It remained susceptible to amikacin, fosfomycin and colistin (Table 1). The imipenem/ethylene diamine tetra-acetic acid (EDTA) combined disk diffusion test was positive since the inhibition zone increased by 7 mm with the imipenem/EDTA disk compared with the imipenem disk alone, suggesting the presence of a metallo-β-lactamase (MBL) [1]. In addition, the double-disk synergy test (between amoxicillin/clavulanic acid and broad-spectrum cepha-losporins) showed the presence of an extended-spectrum β-lactamase (ESBL)-producing phenotype (data not shown). The transferability of the β-lactam resistance determinant was assessed by conjugation assay using an azide-resistant (Az R) mutant of Escherichia coli C600 as the recipient strain. Selection was performed on Mueller-Hinton agar plates supplemented with sodium azide (300 mg/mL) and ertapenem (4 mg/mL). A transfer frequency of ca. 10-4 transconjugants per donor was observed. Comparison of MICs between the transconjugant (Tc-18TA) and its recipient strain (C600 Az R) showed increased resistance not only to the tested β-lactams but also to gentamicin, tobramycin and SXT (Table 1). Total genomic DNA of strain 18TA was screened using different multiplex PCR amplifications for various β-lactamase genes (bla TEM-like , bla SHV-like , bla OXA-1-like , bla CTX-M groups 1, 2, 9, 18 and 25, bla OXA-48-like , bla KPC and bla GES and the MBL genes bla VIM , bla IMP and bla NDM) as described previously [2]. Amplification results following agarose gel electrophoresis analysis showed the presence of group 1 bla CTX-M and bla NDM genes together with bla TEM-like , bla SHV-like and bla OXA-1-like genes. Except for the bla SHV gene that was found in strain 18TA but not in the transconjugant Tc-18TA and that was attributed to the chromosomally-encoded species-specific enzyme of K. pneumoniae, the four other β-lactamases were also found in transconjugant Tc-18TA (Table 1). Amplification of the entire bla genes was performed and subsequent sequencing ((Custom DNA sequencing; Eurofins Genomics GmbH, Ebersberg, Germany) showed the presence of the narrow-spectrum β-lactamase genes bla TEM-1B and bla OXA-1 associated with the bla CTX-M-15 ESBL gene and the bla NDM-1 MBL gene both in 18TA and Tc-18TA (Table 1). Furthermore, amplifications searching for aac(3)-IIa (gentamicin and tobramycin resistance) and sul1 and dfrA1 (sulfamethoxazole and trimetho-prim resistance, respectively) were positive both in 18TA and Tc-18TA. These genes were also present in Kp3771, a ST147 NDM-1-producing K. pneumoniae strain recently recovered from a patient hospitalised in an intensive care unit of University Hospital Tahar Sfar in Tunisia [3]. NDM-1-positive K. pneumoniae strains have been previously described in Tunisia, but only from hospitalised patients [1-5]. The current study reports the first description of K. pneumoniae carrying the carbapenemase NDM-1 in the Tunisian community http://dx.

Aims: Prognosis of lung mathology severity after Covid-19 infection using chest X-ray time series Background: We have been inspired by methods analysing time series of images in remote sensing for change detection. During the current Covid-19 pandemic, our motivation is to provide an automatic tool to predict severity of lung pathologies due to Covid-19. This can be done by analysing images of the same patient acquired at different dates. Since no analytical model is available, and also no accurate quantification tools can be used due to many unknowns about the pathology, feature-free methods are good candidates to analyse such temporal images. Objective: This contribution helps improving performances of medical structures facing the Covid-19 pandemic. The first impact is medical and social since more lives could be saved with a 92% rate of good prognosis. In addition to that, patients in intensive care units (up to 15%) could a posteriori suffer from less sequels due to an early and accurate prognosis of their PP. Moreover, accurate prognosis can lead to a better planning of patient’s transfer between units and hospitals, which is linked to the second claimed economical impact. Indeed, prognosis is linked to lower treatment costs due to an optimized predictive protocol using ragiological prognosis. Methods: Using Convolutional Neural Networks (CNN) in combination with Recurrent Neural Networks (RNN). Spatial and temporal features are combines to analyse image time series. A prognosis score is delivered indicating the severity of the pathology. Learning is made on a publicly available database. Results: When applied to radiological time-series, promising results are obtained with an accuracy rates higher than 92%. Sensitivity and specificity rates are also very interesting. Conclusion: Our method is segmentation-free, which makes it competitive with respect to other assessment methods relying on time-consuming lung segmentation algorithms. When applied on radiographic data, the proposed ProgNet architecture showed promising results with good classification performances, especially for ambiguous cases. Specifically, the reported low false positive rates are interesting for an accurate and personalised care workflow.

BackgroundPublic health recommendations and governmental measures during the COVID-19 pandemic have enforced numerous restrictions on daily living including social distancing, isolation and home confinement. While these measures are imperative to abate the spreading of COVID-19, the impact of these restrictions on health behaviours and lifestyle at home is undefined. Therefore, an international online survey was launched in April 2020 in seven languages to elucidate the behavioral and lifestyle consequences of COVID-19 restrictions. This report presents the preliminary results from the first thousand responders on physical activity (PA) and nutrition behaviours.MethodsThirty-five research organisations from Europe, North-Africa, Western Asia and the Americas promoted the survey through their networks to the general society, in English, German, French, Arabic, Spanish, Portugese, and Slovenian languages. Questions were presented in a differential format with questions related to responses “before” and “during” confinement conditions.Results1047 replies (54% women) from Asia (36%), Africa (40%), Europe (21%) and other (3%) were included into a general analysis. The COVID-19 home confinement had a negative effect on all intensities of PA (vigorous, moderate, walking and overall). Conversely, daily sitting time increased from 5 to 8 hours per day. Additionally, food consumption and meal patterns (the type of food, eating out of control, snacks between meals, number of meals) were more unhealthy during confinement with only alcohol binge drink decreasing significantly.ConclusionWhile isolation is a necessary measure to protect public health, our results indicate that it alters physical activity and eating behaviours in a direction that would compromise health. A more detailed analysis of survey data will allow for a segregation of these responses in different age groups, countries and other subgroups which will help develop bespoke interventions to mitigate the negative lifestyle behaviors manifest during the COVID-19 confinement.

International audience; The Kontsevich formality can be viewed as a non-linear map ℱ from the L∞ algebra of poly-vector fields on ℝd to the space of poly-differential operators. The space of the half-homogenous poly-vector fields is a sub-L∞ algebra. We prove here that the restriction of ℱto this subspace is weakly analytic.

International audience; In response to the fresh water scarcity, Tunisia is utilizing more and more membrane desalination of unconventional resources, including brackish waters and seawater. The widespread reserves of groundwaters and their low salinity make this resource of special interest. Two predominant ionic compositions have been identified depending on their relative proportion of sulfate to chloride ions. The question arising for the decision-makers concerns the choice of membrane technology and, therefore, of membrane. Two nanofiltration (NF) membranes (NF270 and NF90) and a reverse osmosis (RO) one (BW30) were tested in a desalination study of synthetic feeds reproducing the ionic composition of three representative groundwaters. Sulfate/chloride ratio appears to be the key factor for the membrane choice to obtain good quality drinking water meeting the Tunisian standards. Moreover, validation of two prediction tools was investigated: ROSA, software provided by the membrane manufacturer and Nanoflux ® , software specifically designed for NF. The experimental NF results are well fitted by the Nanoflux ® simulations. We concluded that ROSA cannot generally provide good NF predictions because it does not take into account the electric interactions between membrane and feed.