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The concentrations of major, trace (TE), and rare earth (REE) elements and their seasonal and spatial distribution were studied on the fine fraction (&lt, 63 &micro, m) of the sediments of the Lom&eacute, lagoons (West Lake, East Lake, and Lake B&egrave, ). The sediments were collected on a total of nine sampling sites (three per Lake) during two campaigns (dry season and rainy season). The quality of the sediments was assessed on the basis of the enrichment factor (EF) and the labile or non-residual fraction (NRF) in relation to the values recommended for the quality of the sediments (Sediment Quality Guidelines, SQG). The distribution of rare earth elements shows enrichments in light rare earths superior to those of heavy rare earth elements during any season. Positive Ce anomalies are less noticeable and less variable between seasons than Eu anomalies. La/Yb ratios are positively correlated with the percentage of Al and Fe oxides and with the percentage of fine fractions. The main bearing phases of rare earth elements are, therefore, Al and Fe oxides and the finest fractions of the sediments. The concentrations of trace elements vary little, according to the seasons, but show strong variations from one element to another. The degrees of enrichment obtained are moderate for Bi, Cr, Ga, Mo, Pb, Sn, and Zn (1.5 &lt, EF &lt, 5) to significant for As, Cd, and Sb (5 &lt, 20) for all sites of Lake B&egrave, For the sites of West Lake, the degrees of enrichment obtained are moderate for As, Cd, Cu, Mo, and Pb (1.5 &lt, 5) to a significance for As, Bi, Cd, Pb, Sb, Sn, and Zn (5 &lt, 20). Only the East Lake sites show high degrees of enrichment for elements such as Sb and Sn (20 &lt, 40). Trace elements (TE) such as As, Cd, Cu, and Ni have total concentrations within the range of variation of the SQG concentrations (particularly Probable Effect Level (PEL) and Effect Range Median (ERM)), whereas Cr, Pb, and Zn total concentrations are higher. The ranking of priority sites with respect to the sediment contamination is determined according to ERM and PEL quotients in relation to the probability of toxicity for benthic organisms. For almost all the sites, the priority is lowest to medium-low with regard to As, Cd, and Cu and medium-high (Cr and Ni) to highest (Pb and Zn), particularly for the East and West Lakes. Moreover, the NRF can represent significant percentages of the total TE concentrations: 5% to 15% for As, Bi, Ni, V, Mo, and Sc, 15% to 25% for Co, Cu, and Sr, 25% to 40% for Pb and Zn and, lastly, 47% to 55% for Cd.

The increase in the use of Self-consolidating concrete (SCC) raises the problem of their environmental impact, justifying the recent interest in the development of SCC with low binder content (eco-SCC). On the other hand, in most of concrete applications, the casting of SCC is conducted by pumping process due to its numerous advantages, including the ease to transport the material into the casting zones that are barely accessible. The pumpability of SCC depends on the ability of the material to form lubrication layer (LL) as well as its properties. Despite the numerous advances in this domain, predict the pumpability of concrete remains a real challenge. In fact, this requires besides the rheology of the concrete, a good control of the rheological properties and the thickness of LL this concrete could form. However, it is very difficult to identify the LL material during the pumping process. Moreover, the mechanisms of its formation still are less well understood. This limit the determination of LL characteristics and their variations.This project aims firstly to develop an effective approach to proportion SCC with normal and low binder content. Secondly, the study aims to develop an approach to determine the rheological properties of LL. Finally, the project deal with the study of the potential mechanisms involved in the formation of the LL and determine the main parameters controlling these mechanisms. In this project, SCC is considered as a diphasic suspension of coarser particles (> 1.25 mm) in a fluid matrix of fine mortar (< 1.25 mm). A new approach based on the coupled effect of the characteristics of both suspending (fine mortar) and suspended (coarse aggregate) phases was proposed to proportion SCC. Furthermore, new methodology was established to evaluate the rheological properties of the LL, simulated as a diphasic suspension of fine sand (< 1.25 mm) and cement paste. The results showed the significant effect of the volumetric content and packing density of fine sand, as well as cement paste rheology on the visco-elastoplastic characteristics of the lubrication layer. The main mechanisms of LL formation, namely dynamic segregation and Reynolds dilatancy were investigated through a new segregation index and a new established test of Reynolds dilatancy. Other phenomena such as blocking that can occur during the pumping process and influence the formation of LL are evaluated through new proposed test.The proposed optimization approach allows to determine the required characteristics of granular skeleton and fine mortar mixture to obtain SCC with the desired flowability and mechanical performances. The adopted diphasic approach of SCC mixture allowed a better comprehension of the mechanisms of LL formation. The results showed low dynamic segregation of eco-SCC compared to normal SCC. On the other hand, the normal and eco-SCC exhibited comparable Reynolds dilatancy of around 1 % of the initial volume of the mixture. The relative packing density of coarse aggregate was found to govern the mechanism of LL formation. In order to facilitate the selection of the optimal mixture of aggregate for better pumpability, attempt was made to determine the morphological characteristics of aggregate that control their packing density. Then empirical models were established to predict all the phenomena involved in LL formation based on morphological aggregate morphological characteristics and fine mortar mixture properties. Based on the results of this project, different normal and eco-SCC mixtures were recommended regarding their flow performances., L’utilisation croissante des bétons autoplaçants (BAP) a soulevé la question de leur impact environnemental en raison de leurs volumes de liant élevés, justifiant l’intérêt récent pour le développement des BAP à faibles teneurs en matériaux cimentaires (BAP-éco). En outre, dans la plupart des applications, la mise en place des BAP se fait par la technique de pompage grâce à ses nombreux avantages notamment la facilité d’acheminer le matériau jusqu’à des zones de mise en place difficiles d’accès. La pompabilité du béton dépend de la capacité de ce matériau à former une couche limite (CL) et des propriétés de celle-ci. Malgré les récentes avancées enregistrées dans ce domaine, prédire la pompabilité du béton reste un défi important. En effet, en plus des propriétés rhéologiques du béton, une bonne connaissance de la rhéologie et de l’épaisseur de CL qu’il peut former est nécessaire. Cependant, l’identification du matériau de cette couche lors du pompage est très difficile. En plus, les mécanismes de sa formation sont moins connus. Ce qui limite les connaissances actuelles sur l’évaluation de ses caractéristiques et leurs variations.Ce projet de thèse vise d’abord à développer une approche pratique pour la formulation des BAP à teneur en liant faible et normale. Ensuite, l’étude vise à proposer une approche pour évaluer les propriétés rhéologiques de CL. Enfin, il sera question d’étudier les mécanismes potentiels intervenant dans la formation de LL et mettre en évidence les principaux paramètres qui les gouvernent. Dans cette étude, le BAP est considéré comme un mélange diphasique constitué de gros granulats (> 1,25 mm) et d’une matrice fluide, de mortier fin (< 1,25 mm). Ainsi, une approche d’optimisation de BAP basée sur les caractéristiques de ces deux phases a été proposée. En outre, une méthodologie établie a permis d’évaluer les propriétés rhéologiques de CL qui a été simulée comme une suspension des particules fines de sable (< 1,25 mm) et de la pâte de ciment. Les résultats ont montré l’effet significatif des particules fines de sable ainsi que la rhéologie de la pâte de ciment sur les propriétés visco-élastoplastiques de CL. Les principaux mécanismes de la formation de CL qui sont la ségrégation dynamique et la dilatance de Reynolds ont été investiguées respectivement à travers un nouvel indice de ségrégation et un nouvel essai de dilatance. D’autres phénomènes comme le blocage pouvant apparaître lors du pompage de BAP et influencer la formation de CL ont été également évalués.L’approche d’optimisation proposée permet de déterminer les propriétés du mélange granulaire et du mortier fin nécessaires pour l’obtention d’un BAP de performances d’ouvrabilité et mécaniques visées. L’approche diphasique du BAP a permis une meilleure compréhension des mécanismes de formation de CL à travers l’influence des caractéristiques des deux phases du mélange de BAP. Les résultats ont montré une plus faible ségrégation dynamique des BAP-éco par rapport aux BAP conventionnels. Par ailleurs, Les deux types de BAP développent une dilatance de Reynolds comparable de l’ordre de 1% du volume initial lors de leur cisaillement. Le degré d’empilement initial du squelette granulaire s’est révélé comme paramètre dominant les mécanismes de formation de CL. Ce paramètre dépend directement des caractéristiques morphologiques des granulats. Afin de faciliter le choix du mélange granulaire optimal pour une meilleur pompabilité du BAP, une nouvelle méthode est mise en place pour déterminer les principales caractéristiques morphologiques des granulats qui gouvernent leurs compacités. Par la suite, des modèles de prédiction de l’ensemble des mécanismes de formation de CL en fonction des caractéristiques morphologiques des granulats et les propriétés du mortier fin ont été proposés. A partir des résultats issus de cette étude, différents mélanges de BAP conventionnel et BAP-éco ont été recommandés selon leur performances d’écoulement.

The objective of this study was the evaluation of the health risks of the pesticides use and their bioaccumulation by the vegetables grown in Lome gardens. Pesticide residues levels were assessed in vegetable samples collected in Lome areas by Gaz chromatography - mass spectrometry or liquid chromatography - mass spectrometry in order to know their concentrations. Data obtained were used for estimating the potential health risks associated with the exposures to these pesticides.The results showed that all of the samples contain pesticide residues with high levels of Dithiocarbamates (7.79 ppm) in carrots, Chlorpyriphos ethyl (0.445 ppm) in spinach, cucumbers (0.239 ppm), peppers (0.032 ppm), and turnips. Levels above the maximum residue limits (MRLs) of chlorothalonil, and carbendazime were found in peppers, prothioconazole and pendimethalin in turnips, cypermethrin in pepper (0.254 ppm) and in eggplant (0.037 ppm). The pepper has concentrated 5 residues, leek and turnip 4 residues each other, African eggplant 3, lettuce 2 residues and spinach 2 residues. The health risks indices show that the detected pesticides could not be considered as a serious public health problem in the studied conditions, but there is the need to increase their monitoring to reduce their misuse on the vegetables. Keywords : Pesticides residues, vegetables, consumers, health risks indices, Lome-togo.

International audience; A self-control method of vibrations is presented in this paper. This method combines the passive damping capabilities afforded by viscoelastic materials with the active control properties associated with piezoelectric materials. Active control is introduced, using the piezoelectric properties, in order to improve the reduction in vibration amplitudes that can be obtained by viscoelastic passive damping alone. To this end, a filter has been mounted between the sensors and actuators. The resulting nonlinear problem is discretized using the recently developed solid–shell finite element SHB20E, due to the advantages it offers in terms of accuracy and efficiency, as compared to standard finite elements with the same geometry and kinematics. In order to solve the discretized problem, a resolution method using DIAMANT approach is developed. A set of selective and representative numerical tests are performed on multilayer plates to demonstrate the interest of the proposed damping model.

Climate change has become the scourge environmental concern and mobilizes more theinternational community. The outcome of this mobilization remains probably the implementation ofinternational climate change regime for which the Climate Convention and the Kyoto Protocol are the legalbases. This system is innovative in that it sets quantified emission reduction commitments for greenhouse gasemissions (GHG) for polluters States, but also in that it establishes mechanisms known as of “flexibility”whose implementation is accompanied by a control based on a Committee known as of “compliance”. Butdespite all this normative production, it is regrettable that today the international climate regime is a realfailure. Indeed, if the mobilization of states is no doubt, however, the same states that have voluntarily agreedto engage deliberately refuse to honour their commitments for essentially political, economic and strategicreasons. This work therefore aims to shed light on the causes of this failure by developing a mixed record ofthe first Kyoto commitment ended period in 2012, and offers prospects for a legal regime of the post-Kyotoclimate and efficient, able to be up to the challenges., Le changement climatique est devenu aujourd’hui le fléau environnemental qui préoccupe etmobilise le plus la communauté internationale. L’aboutissement de cette mobilisation générale reste sansdoute la mise en place du régime international de lutte contre le changement climatique dont la Conventioncadredes Nations Unies sur le changement climatique et le Protocole de Kyoto constituent les basesjuridiques. Ce régime innove en ce qu’il fixe des engagements quantifiés de réduction des émissions de gaz àeffet de serre pour les États pollueurs, mais aussi en ce qu’il instaure des mécanismes dits de « flexibilité »dont la mise en oeuvre est assortie d’un contrôle original basé sur un Comité dit de « l’observance ». Mais, endépit de toute cette production normative, il est regrettable de constater aujourd’hui que le régimeinternational du climat est un véritable échec. En effet, si la mobilisation des États ne fait aucun doute, enrevanche, les mêmes États qui ont volontairement accepté de s’engager refusent délibérément d’honorer leursengagements pour des raisons essentiellement politiques, économiques et stratégiques. Ce travail ambitionnedonc de lever le voile sur les causes de cet échec en dressant un bilan mitigé de la première périoded’engagement de Kyoto qui a pris fin en 2012, et propose des perspectives pour un régime juridique duclimat post-Kyoto efficient et efficace, en mesure d’être à la hauteur des enjeux.

Colloque avec actes et comité de lecture. Internationale.; International audience; Exigences pour le respect de l'environnement encouragent à réduire l'impact de l'activité humaine sur la nature. Génie civil répond à ces exigences par le développement de matériaux de construction écologiques. Cet article traite de la transformation de l'argile matières premières qui permettent le traitement de matériaux de construction respectueux de l'environnement: en plus de leur biodégradabilité, les alvéoles ont tiré matériaux argileux permettent des économies d'énergie en chauffage de la maison grâce à leurs propriétés d'isolation thermique. Mais leur fabrication est un procédé de forte consommation d'énergie, en particulier pendant le compactage, le séchage et la cuisson qui contribuent à l'émission de gaz de serre. Le but de cet article est d'étudier la rhéologie des pâtes d'argile afin de développer des procédés de fabrication à faible consommation d'énergie. A cet effet, les approches théoriques et expérimentaux ont été réalisés sur six variétés d'argile. Dans l'approche théorique, un élément fini (FE) modèle de simulation a été développé pour presser un matériau non rigide prédire les déformations et les contraintes se produisant dans la structure de l'argile. Des expériences ont ensuite été effectuées pour valider la modélisation par éléments finis. Dans cette approche expérimentale, les pâtes d'argile ont été transformées avec une teneur en eau en respectant les limites d'Atterberg qui déterminent la plasticité de l'argile. Le compactage des échantillons a été réalisée sous chargements variables afin de déterminer la faible charge appropriée de la consommation d'énergie. La présente étude est réalisée dans le cadre d'un projet de recherche coopérative, y compris les laboratoires suivants: Institut de Recherche sur le Transport, l'Energie et la Société IRTES-M3M Belfort / France (TCHOMBI et al, 2012, [2], civil et génie des matériaux Département-Ecole Royale Militaire de Bruxelles / Belgique, Centre de la Construction et du Logement-Unité de Recherche sur les Matériaux et les Agroressources , le CCA-URMA-Togo.

Efficiency of organic photovoltaic cells based on organic electron donor/organic electron acceptor junctions can be strongly improved when the transparent conductive Anode is coated with a Buffer Layer (ABL). Here, the effects of a metal (gold) or oxide (molybdenum oxide) ABL are reported, as a function of the Highest Occupied Molecular Orbital (HOMO) of different electron donors. The results indicate that a good matching between the work function of the anode and the highest occupied molecular orbital of the donor material is the major factor limiting the hole transfer efficiency. Indeed, gold is efficient as ABL only when the HOMO of the organic donor is close to its work function Phi(Au). Therefore we show that the MoO(3) oxide has a wider field of application as ABL than gold. (C) 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

International audience; The life-time of multi-layer organic solar cells based on the couple donor acceptor copper phthalocyanine/fullerene is studied as a function of the nature of the exciton blocking layer (EBL). It is shown that organic EBL are more efficient than are the inorganic In2S3 EBLs. Moreover among the organic EBL, Alq3 is the most efficient EBL protecting layer. An organic solar cell's lifetime depends on oxygen- and water-contamination of the organic materials. The solar cell's degradation may correspond to bulk or interface phenomena. Using equivalent electrical schemes of solar cell diodes, we show that the structure degradation is mainly related to bulk modification. It is proposed that oxygen- and water-diffusion into the C60 induce a large increase in its resistivity and, therefore an increase in the series resistance, which decreases the solar cell efficiency. In the case of In2S3 EBLs, the degradation law predicts that with time two different phenomena will be present. The classical oxygen- and water-diffusion into the organic material, during the first hour of air exposure, leads to a modification in the In2S3 EBL/organic interface properties.

International audience; The effects of logging residue management practices on export and dynamics of nutrients were studied in a plantation of Pinus radiata D. Don growing on an infertile soil, in a humid, temperate area of NW Spain. The export of nutrients due to the removal of wood and logging residues during thinning and clear-cutting was evaluated by estimation of nutrient stores in the above-ground biomass and in the soil. Nutrient dynamics in decomposing slash needles and twigs were monitored over one year in a thinned stand and in an adjacent clear-cut area. Comparison of nutrient release in decaying residues with the nutrient store in tree biomass as well as inputs via litterfall and atmosphere allowed discussion of possible implications for sustainable sylviculture in these plantations. Nutrient release from decomposing material increased following clear-cutting and to an even greater extent, after mechanical incorporation of logging residues to the mineral soil, which substantially increased the short-term flush of some nutrients.; Effets des pratiques forestières sur la nutrition d'un peuplement de Pinus radiata : exportation des éléments minéraux et dynamique des résidus en décomposition. Les effets de l'utilisation des résidus d'exploitations forestières sur l'exportation et la dynamique des éléments minéraux ont été étudiés dans une plantation de Pinus radiata D. Don située sur une station non fertile et dans une région humide et tempérée du Nord-Ouest de l'Espagne. Le flux d'éléments minéraux dû à l'exportation du bois et des résidus de l'exploitation forestière à la suite d'une éclaircie et d'une coupe rase a été évalué à partir de l'estimation des réserves d'éléments minéraux dans la biomasse aérienne forestière et dans le sol. La dynamique des éléments minéraux provenant des résidus en décomposition d'aiguilles et de brindilles a été suivi pendant un an dans une parcelle éclaircie et aussi dans une zone de déboisement adjacente. La comparaison de la libération d'éléments minéraux en décomposition avec la réserve d'éléments minéraux dans la biomasse des arbres, de même que les apports par les pluviolessivats et les pluies incidentes nous ont permis de discuter des implications possibles pour assurer la pérennité de la production forestière. La libération des éléments minéraux à partir de matières en décomposition augmente après le défrichement total, et ceci tout particulièrement après l'incorporation mécanique des résidus d'exploitations forestières au sol minéral, laquelle augmente de façon appréciable la libération d'éléments minéraux.

International audience; This editorial summarizes the contributions presented during the Estate Quantistica 2018 and published in a special issue of Universe (...).

Artemether (ATM) cardiotoxicity, its short half-life and low oral bioavailability are the major limiting factors for its use to treat malaria. The purposes of this work were to study free-ATM and ATM-loaded poly-ε-caprolactone nanocapules (ATM-NC) cardiotoxicity and oral efficacy on Plasmodium berghei-infected mice. ATM-NC was obtained by interfacial polymer deposition and ATM was associated with polymeric NC oily core. For cardiotoxicity evaluation, male black C57BL6 uninfected or P. berghei-infected mice received, by oral route twice daily/4 days, vehicle (sorbitol/carboxymethylcellulose), blank-NC, free-ATM or ATM-NC at doses 40, 80 or 120 mg kg−1. Electrocardiogram (ECG) lead II signal was obtained before and after treatment. For ATM efficacy evaluation, female P. berghei-infected mice were treated the same way. ATM-NC improved antimalarial in vivo efficacy and reduced mice mortality. Free-ATM induced significantly QT and QTc intervals prolongation. ATM-NC (120 mg kg−1) given to uninfected mice reduced QT and QTc intervals prolongation 34 and 30%, respectively, compared with free-ATM. ATM-NC given to infected mice also reduced QT and QTc intervals prolongation, 28 and 27%, respectively. For the first time, the study showed a nanocarrier reducing cardiotoxicity of ATM given by oral route and it was more effective against P. berghei than free-ATM as monotherapy.

In press, accepted manuscript; International audience; The southern portion of the Gavião Paleoplate is composed by Archean orthogneisses, Archean-Paleoproterozoic metavolcano-sedimentary rocks and Siderian-Rhyacian-Orosirian granitoids. Petrographic, geochemical, U-Pb (Laser Ablation, ICPMS) and Sm-Nd data are presented for five Paleoproterozoic granitoids that were recently mapped: Jussiape II, Lagoa das Almas, Humaitá, Belo Campo and Broco granitoids. These granitoids present U-Pb zircon (LA-ICPMS) ages of 2,052 ± 43, 2,114 ± 24, 2,140 ± 9, 2,049 ± 23 and 2,038 ± 8 Ma, respectively. In addition to these granitoids, another twenty-five ones were identified and studied by several authors, resulting in a total of twenty-nine plutons. Despite the previous petrography, geochemistry and geochronology studies that have been performed, no model had been proposed to explain the tectonic setting of this extensive granitogenesis. Integration Integration of the new data and the literature has been done and corresponds to the second part of the article. Based on U-Pb dating and geochemical data, Siderian-Rhyacian-Orosirian granitoids of the southern Gavião Paleoplate were classified into five groups, or five suites: 1 (2,324 ± 6 to 2,091±6.6 Ma), 2a (2,054 -6/+8 to 2,041±23 Ma), 2b (2,066±37 to 2,019±32 Ma), 2c (2,058 ±8 to 1,852±50 Ma) and 2d (2,049±12 to 1,929±16 Ma). The granitoids of Group 1 present heterogeneous deformation, while the granitoids of groups 2a to 2d are generally not deformed. Usually the rocks are potassic, but sodic granitic rocks can be found in samples of groups 1, 2c and 2d. Several chemical classification parameters are presented and discussed herein, but it is noteworthy that the granitoids of Group 1 are mainly classified as calcic to calc-alkalic, while the rocks of the second group are mostly classified as alkalic ones. In the remaining groups, the samples vary between calc-alkalic and alkali-calcic. The εNd values range between 4.0 and -15.4 and suggest an important and varied share of the continental crust in the formation of these rocks. The Humaitá granitoid probably presents the lowest contribution from the continental crust in its genesis. The rocks from Group 1 were generated as the product of an active continental margin arc situated eastwards from the southern portion of the Gavião Paleoplate. The spatial distribution between the granitoids of groups 1 and 2a suggests westwards subduction and led to a cordilleran model for the Western Bahia Magmatic Arc. Continental collision between the Gavião and Jequié paleoplates occurred around 2.09 Ga and was followed by the setting of late-collision granitoids of groups 2a to 2d. The comparison between the tectonic model presented in this study and other existing models that explain the Siderian-Rhyacian-Orosirian granitogenesis of the Mineiro Belt and Mantiqueira Complex suggests a continuation of the Western Bahia Magmatic Arc and of the collisional orogen that followed, towards the south. The Western Bahia Magmatic Arc emplacement occurred before the Paleoproterozoic granitogenesis of the Serrinha (Bahia-Brazil) and Congo (Africa) paleoplates.

Assessing Creepy Crawlies Arthropods are the most diverse group of terrestrial animal species, yet estimates of the total number of arthropod species have varied widely, especially for tropical forests. Basset et al. (p. 1481 , see the cover) now provide more reliable estimates of total arthropod species richness in a tropical rainforest in Panama. Intensive sampling of a half hectare of forest yielded just over 6000 arthropod species. Scaling up this result to the whole forest suggests that the total species diversity lies between 17,000 and 40,000 species.

International audience

International audience; Iron bulk self-diffusion coefficients were measured in Fe2O3 single crystals using an original methodology based on the utilization of 57Fe stable isotope as iron tracer, and depth profiling by secondary ion mass spectrometry (SIMS). The iron self-diffusion coefficients were measured along and perpendicular to c-axis direction, between 900 and 1100o C, in oxygen atmosphere. Along c-axis they can be described by D//c (cm2/s)= 5.2x106 exp [-510 (kJ/mol)/RT], and are close to reliable data available in the literature, obtained by means of radioactive techniques. Perpendicular to c-axis, Dπc (cm2/s)= 83 exp [-430 (kJ/mol)/RT], and the coefficients are smaller than coefficients along c-axis. The results are compared with previously obtained results of cation bulk self-diffusion in Cr2O3 and in Al2O3 single crystals.

International audience; Neoproterozoic granitoid suites in southeastern Brazil are closely related to the different tectonic events. Petrography, geochemistry and structural features allow to separate these rocks into pre-, syn-, late and post-tectonic granitoids. The whole emplacement process lasted less than 100 Ma: from 595 Ma for the pre-tectonic granitoids, to 500 Ma for the post-tectonic ones. During this interval a 45 Ma magmatic quiet period (from 582 to 537 Ma) can also be characterized. Detailed field observations and mapping, coupled with petrological and geochemical observations, indicate an important role of the Archaean and Paleoproterozoic crust in the genesis of these granitoids, showing even evidences of some mantle interactions.

International audience; Two pegmatite groups are represented in southeastern Brazil. The first group, resulting from fractional crystallization, is linked to syn-tectonic granites (580 Ma - deformation event D ) and the second one is associated with another partial melting event of the crust which simultaneously produced porphyritic leucogranites [(520-500 Ma)- later deformation event D2] and pegmatites themselves. The Fe/Mn ratios of tourmalines, micas and columbite-tantalites decrease continuously from simple pegmatites to gem quality elbaite-rich ones. The Fe/Mn ratio has been used as a qualitative fractionation index which seems to reflect the regional zoning of the first pegmatites group around a hidden granite body. The Fe/Mn ratio values correlate negatively with Na and Li contents in tourmalines and mica. The REE, Nb, Co and Zn contents in tourmalines, micas, and columbite-tantalites are controlled by their mineral assemblages.

International audience; The Urucum Suite granitoids (Rio Doce region southeastern Brazil) contains four main facies: megafeldspar granites, deformed medium-to-coarse-grained granites, tourmaline, and pegmatitic facies. they intrude both the staurolite-garnet-muscovite-biotite schist of the Sao Tome formation (Rio Doce Group) and the Galileia metaluminous suite (596±4 Ma). Detailed structural studies suggest that the Urucum Suite emplaced during an important dextral strike-slip movement (D1 phase) of the Brasiliano orogeny (650-450 Ma). Modal and chemical mineralogical variations suggest an evolution from the megafeldspar facies to the pegmatitic facies. Whole-rock geochemistry indicates the peraluminous character of the Urucum suite granitoids, the evolution from the megafeldspar facies granites to pegmatite facies granites to pegmatitic facies granites and suggests the syn-collisional character of this suite. U-Pb zircon (582± 2 Ma) and monazite (576-573 ±4 Ma) data indicate that the Urucum Suite emplaced during the Brasiliano orogeny. The peraluminous nature of the Suite and isotopic rich character in the Rb-Sr (87 Sr/86 Sr = 0.7114 to 0.7165) and Sm Nd (eNd(T) = -7.4 and -8.2) systems indicate that it formed by partial melting of older intermediate to felsic crustal sources. Based on early Proterozoic model-ages (2.3 to 1.8 Ga) and on 2.0 ga U-Pb inherited signature, granitoids of the Suite are probably derived from a rocks with a long crustal residence (Transamazonian basement), without extensive mantle contribution

International audience; Kesnact S Tb geocinonology and St-Nd isotopes of Ganicia and Grachnn Ncoproterozoic granitoids suites in south-eastern Brazil. U-Pb zircon and monazite dating and whole-rock Sr-Nd isotopes have been applied on Neoproterozoic granitoids from the Atlantic shear belt, south-eastern Brazil. U-Pb zircon results on the Galiléia metaluminous and Urucum peraluminous suites indicate crystallisation ages of 594 ± 6 Ma and 582 ± 2 Ma respectively. Whole-rock Rb-Sr and Sm-Nd analyses on representative samples from both suites demonstrate that they mainly derive from melting of older crustal rocks. The occurrence of an old isotopic memory in the zircons from the Urucum granitoids around 2.2 Ga, in agreement with Nd model ages, suggests a Palaeoproterozoic age for the crustal protolith of these two suites, probably associated with the Transamazônico event. Owing to these new dating results and previous regional geochronological data, it can lie proposed that the metaluminous magmatism ended around 590 Ma and that the collisional peraluminous magmatism associated with the Brasiliano progeny occurred between 584 and 570 Ma.

International audience; Ants are a major ecological group in tropical rainforests. Few studies in the Neotropics have documented the distribution of ants from the ground to the canopy, and none have included the understorey. A previous analysis of an intensive arthropod study in Panama, involving 11 sampling methods, showed that the factors influencing ant β diversity (i.e., changes in assemblage composition) were, in decreasing order of importance, the vertical (height), temporal (season), and horizontal (geographic distance) dimensions. In the present study, we went one step further and aimed (1) to identify the best sampling methods to study the entire ant assemblage across the three strata, (2) to test if all strata show a similar horizontal β diversity and (3) to analyze the functional structure of the entire ant assemblage. We identified 405 ant species from 11 subfamilies and 68 genera. Slightly more species were sampled in the canopy than on the ground; they belonged to distinct sub-assemblages. The understorey fauna was mainly a mixture of species found in the other two strata. The horizontal β diversity between sites was similar for the three strata. About half of the ant species foraged in two (29%) or three (25%) strata. A single method, aerial flight interception traps placed alongside tree trunks, acting as arboreal pitfall traps, collected half of the species and reflected the vertical stratification. Using the functional traits approach, we observed that generalist species with mid-sized colonies were by far the most numerous (31%), followed by ground- or litter-dwelling species, either specialists (20%), or generalists (16%), and arboreal species, either generalists (19%) or territorially dominant (8%), and finally army ants (5%). Our results reinforce the idea that a proper understanding of the functioning of ant assemblages requires the inclusion of arboreal ants in survey programs.

Lyso-7 is a novel synthetic thiazolidinedione, which is a receptor (pan) agonist of PPAR α,β/δ,γ with anti-inflammatory activity. We investigated the cardiotoxicity of free Lyso-7 in vitro (4.5–450 nM), and Lyso-7 loaded in polylactic acid nanocapsules (NC) in vivo (Lyso-7-NC, 1.6 mg/kg). In previous work, we characterized Lyso-7-NC. We administered intravenously Lyso-7, Lyso-7-NC, control, and blank-NC once a day for seven days in mice. We assessed cell contraction and intracellular Ca2+ transients on single mice cardiomyocytes enzymatically isolated. Lyso-7 reduced cell contraction and accelerated relaxation while lowering diastolic Ca2+ and reducing Ca2+ transient amplitude. Lyso-7 also promoted abnormal ectopic diastolic Ca2+ events, which isoproterenol dramatically enhanced. Incorporation of Lyso-7 in NC attenuated drug effects on cell contraction and prevented its impact on relaxation, diastolic Ca2+, Ca2+ transient amplitude, Ca2+ transient decay kinetics, and promotion of diastolic Ca2+ events. Acute effects of Lyso-7 on cardiomyocytes in vitro at high concentrations (450 nM) were globally similar to those observed after repeated administration in vivo. In conclusion, we show evidence for off-target effects of Lyso-7, seen during acute exposure of cardiomyocytes to high concentrations and after repeated treatment in mice. Nano-encapsulation of Lyso-7 in polymeric NC attenuated the unwanted effects, particularly ectopic Ca2+ events known to support life-threatening arrhythmias favored by stress or exercise.

International audience; The paleogeography of the Meso-Neoproterozoic Rodinia supercontinent remains debated partly because many stable cratons still lack reliable paleomagnetic data for this period. A new geochronological and paleomagnetic study was conducted on the NNW-trending Manso dyke swarm of southern West Africa (Ghana) to clarify the position of this unconstrained continent in Rodinia. Two Usingle bondPb apatite ages of 857.2 ± 8.5 Ma and 855 ± 16 Ma agree with one previous baddeleyite age, indicating a ~ 860 Ma emplacement age for the Manso dykes. A characteristic remanent magnetization (ChRM) was isolated in stable single to pseudo-single domain (SD-PSD) magnetite. Well constrained site mean directions obtained for 13 dykes lead to a mean direction for the Manso dyke swarm of Dm = 181.9°, Im = −77.2° (N = 13, α95 = 7.6°, k = 30.6), yielding a paleomagnetic pole at 177.6°E, 28.3°S, (A95 = 12.7 °K = 11.6). Two directional clusters of opposite inclination pass a reversal test (C-class) and the primary origin is supported by a positive baked contact test, satisfying all the seven R-criteria to provide the first West African Tonian key paleomagnetic pole. This key pole indicates a high latitude for the West Africa Craton during the emplacement of the ~860 Manso dykes. A compilation of reliable paleomagnetic poles for West Africa, Baltica, Amazonia and Congo-São Francisco cratons suggests that these cratons were together between ~1200 and 800 Ma in a long-lived WABAMGO configuration. We suggest that the collision of this block with Laurentia along the Grenvillian-Sunsás orogens closed the external Nuna Ocean and formed Rodinia by extroversion.

This article presents an experience of a participative approach preliminary to the implementation of NR-36, which regulates work in meat and meat products companies. Although the norms provide for worker participation in the processes of implementing job rotation, they do not explain how to do it. The study was developed in the beef slaughtering sector using two complementary methods: observation of the work in loco, in order to select the jobs that are primarily eligible for the rotation, and a survey of the workers' perception of the level of acceptance of the rotation in the selected jobs. At first, 72% of the workers did not accept the rotation. After inclusion and participation in the implementation process, 86% of the workers in the dirty area and 64% in the clean area agreed to the rotation. As evidence of the advantages of the rotation, the variability in the work (30%), learning and gain of experience (40%), changes in movements (35%), and physical rest (32%) stand out. As disadvantages, the fear of accidents (30%) and the fear of change and of the unknown (25%) stand out. We conclude that the participatory approach preliminary to the changes in organizational design contributes to the understanding and perception of workers about the advantages and disadvantages of the rotation, indicating improvement of processes in compliance with legal requirements.; Esteartigo apresentaexperiência de abordagem participativa preliminar à implantação da NR-36, que regula o trabalho em empresas produtoras de carne e derivados. Apesar de a normativa prevera participação do trabalhador nos processos de implantação de rodízio de postos, não esclarececomo fazê-lo. O estudo foi desenvolvido no setor de abatede bovinos utilizando dois métodos complementaresentre si: observações do trabalho in loco, para seleção dos postos prioritariamente elegíveis ao rodízio, elevantamento da percepção argumentada dos trabalhadores sobre o nível de aceitaçãode realização do rodízio nos postos selecionados. A princípio, 72% dos trabalhadores não aceitavam realizar o rodízio. Após inclusão e participação no processo de implantação, 86% dos trabalhadores da área suja e 64% da área limpa concordaram em realizar. Como evidências das vantagensem realizar rodízio, avariabilidade no trabalho (30%), aprendizado e ganho de experiência (40%), mudanças de movimentos (35%) e descanso físico (32%) se destacam. Como desvantagens, sobressaem o medo de acidentes (30%) e o medo da mudança e do desconhecido (25%). Concluímosque a abordagem participativa preliminar às mudanças de desenhos organizacionais contribui na compreensão e percepção dos trabalhadores sobre as vantagens e desvantagens do rodízio, indicando melhoria dos processos no cumprimento das exigências legais.

International audience; Carbon isotope compositions of both sedimentary carbonate and organic matter can be used as key proxies of the global carbon cycle and of its evolution through time, as long as they are acquired from waters where the dissolved inorganic carbon (DIC) is in isotope equilibrium with the atmospheric CO2. However, in shallow water platforms and epeiric settings, the influence of local to regional parameters on carbon cycling may lead to DIC isotope variations unrelated to the global carbon cycle. This may be especially true for the terminal Neoproterozoic, when Gondwana assembly isolated waters masses from the global ocean, and extreme positive and negative carbon isotope excursions are recorded, potentially decoupled from global signals. To improve our understanding on the type of information recorded by these excursions, we investigate the paired δ13Ccarb and δ13Corg evolution for an increasingly restricted late Ediacaran-Cambrian foreland system in the West Gondwana interior: the basal Bambuí Group. This succession represents a 1st-order sedimentary sequence and records two major δ13Ccarb excursions in its two lowermost lower-rank sequences. The basal cap carbonate interval at the base of the first sequence, deposited when the basin was connected to the ocean, hosts antithetical negative and positive excursions for δ13Ccarb and δ13Corg, respectively, resulting in Δ13C values lower than 25‰. From the top of the basal sequence upwards, an extremely positive δ13Ccarb excursion is coupled to δ13Corg, reaching values of +14‰ and −14‰, respectively. This positive excursion represents a remarkable basin-wide carbon isotope feature of the Bambuí Group that occurs with only minor changes in Δ13C values, suggesting change in the DIC isotope composition. We argue that this regional isotopic excursion is related to a disconnection between the intrabasinal and the global carbon cycles. This extreme carbon isotope excursion may have been a product of a disequilibria between the basin DIC and atmospheric CO2 induced by an active methanogenesis, favored by the basin restriction. The drawdown of sulfate reservoir by microbial sulfate reduction in a poorly ventilated and dominantly anoxic basin would have triggered methanogenesis and ultimately methane escape to the atmosphere, resulting in a13C-enriched DIC influenced by methanogenic CO2. Isolated basins in the interior of the Gondwana supercontinent may have represented a significant source of methane inputs to the atmosphere, potentially affecting both the global carbon cycle and the climate.

International audience; The bioadsorbent C1, which is a chitosan derivative prepared in a one-step synthesis, was successfully used to adsorb Cr(VI) and Cu(II) simultaneously. Here, for the first time the simultaneous adsorption of a cation and an anion was modeled using the Corsel model for kinetics and the Real Adsorbed Solution Theory model for equilibrium data. Batch studies of the adsorption of Cu(II) and Cr(VI) in single and binary aqueous solutions were performed as a function of initial solute concentration, contact time, and solution pH. The maximum adsorption capacities of C1 in single and binary aqueous solutions were 1.84 and 1.13 mmol g−1 for Cu(II) and 3.86 and 0.98 mmol g−1 for Cr(VI), respectively. The reuse of C1 was investigated, with Cu(II) ions being almost completely desorbed and fully re-adsorbed. For Cr(VI), the desorption was incomplete resulting in a lower re-adsorption. Energy-dispersive X-ray spectroscopy was used for mapping the distributions of Cr(VI) and Cu(II) adsorbed on the C1 surface in single and binary adsorption systems. Isothermal titration calorimetry experiments were performed for Cr(VI) and Cu(II) adsorption in single solutions. The thermodynamic parameters of adsorption showed that the adsorption of both metal ions was enthalpically driven, but entropically unfavorable.

The Carajas Basin, Amazonian Craton, hosts extensive Neoarchean to Paleoproterozoic sedimentary archives, which are still poorly constrained regarding their depositional settings, ages, and type of basin in which they have been deposited. In this study, we performed detailed sedimentological investigations and U-Pb dating of detrital zircon in four drill cores intercepting the recently defined Serra Sul Formation. Our data show that this formation corresponds to various shallow to deep subaqueous environments. Shallow water environments are characterized by local occurrences of microbially-mediated structures, while deep water environments are characterized by polymictic conglomerates resulting from the mixing of materials of different origins during downslope debris flow. Both sedimentary facies and common occurrence of syn-sedimentary deformations attest for recurrent slope instabilities. Geochronological investigations allow to define a maximum depositional age of 2684 ± 10 Ma, that is several tens million years younger than other Neoarchean sedimentary units of the Carajas Basin. Major peaks in age distribution indicate that the Serra Sul Formation derives from local sources that constitute the basement of the Carajas Basin. The infilling of the Carajas Basin by local sources, together with sedimentary facies and depositional environments attesting for slope instabilities, suggest that the Serra Sul Formation was deposited during an active extensional tectonic phase. Such Neoarchean to early Paleoproterozoic tectonic setting compares with those documented in many other cratons worldwide and suggests that it could correspond to the break-up of one of the first documented supercontinent.

The project Math & The City is a cooperation project on outdoor mathematics (math trails) and ethnomodelling between the University of Oslo and the Federal Unversity of Ouro Preto.

International audience; This study investigates historical fire regimes and arboreal cover variability in the Brazilian Cerrados, a large Neotropical savanna ecosystem, during the Pleistocene-Holocene transition and early Holocene, and then tests whether the observed variation is linked to South American Summer Monsoon (SASM) variability. We present high-resolution pollen, XRF and charcoal records from lake Lagoa Feia, located in central Cerrados, and assess how they compare with other pollen records from the surrounding region to investigate regional trends of vegetation and fire regime variability. Our results show that the Pleistocene-Holocene transition was marked by a wet episode, which included moist forest expansion and rising lake levels, that correlates well with increased monsoon activity in a large area of central South America during the same period. This wet episode chronologically coincides with the Younger Dryas cold episode in the northern hemisphere. Our data revealed moisture declines in central Cerrados after 11.2 kyr BP, along with centennial-scale fluctuations from dry to wet conditions throughout the early Holocene period until around 6 kyr BP. These dry/wet oscillations are associated with weakened SASM activity and repeated shifts of its belt position during this time range. Fire activity increased in central Cerrados just after the onset of drier conditions during the early Holocene, and likely contributed to decreased arboreal cover at that time. A trend of increasing moisture in the region was observed after 6 kyr BP. Our study reveals how centennial and millennial-scale changes in monsoon activity influenced arboreal cover, diversity and fire regimes in the central Cerrados.

This study aimed to characterize the alteration features comprising the genesis and formation of soils on pyroclasts of Trindade Island (TI), South Atlantic, Brazil. Collections of samples were made at the Holocene Paredão volcano (Profile P1) and the Late Quartenary Morro Vermelho Formation (profiles P2, P3 and P4). The pyroclasts of P1 and P2 are volcanic breccia deposit, whereas of P3 is a lapilli deposit. P4 presents fragments of rocks with mineralogical composition different from other profiles suggesting another event of deposition of pyroclastic bombs. The eruptions associated can be regarded as strombolians. Optical microscope supported by X-ray diffraction analysis revealed a mixture of biotite, goethite, ilmenite, anatase, magnetite, hematite, pyroxene, zeolites, and olivine as their main mineral components. Petrologic analysis shows sideromelane that changes to palagonite, indicating a phreatomagmatic eruption. Infrared analyses in the palagonitized regions revealed the presence of halloysite, suggesting alteration of sideromelane to tubular clay minerals. Amygdales and microfractures are partially or totally filled with zeolites, which are formed by the percolation of water that reacts with the palagonite and precipitation of chemical elements of hydrothermal fluid. Iddingsite and Ti-magnetites occur in the fractures and edges of the olivine. The advance of the alteration towards the soil profile, leaving only relicts of olivine or reaching their total transformation in the upper horizons, shows that weathering is the main process of iddingsite formation. Some Ti-magnetites are zoned with Cr-rich core and Cr-poor edge, suggesting a mantelic origin. The augite and diopside explain the high trace elements contents. Geochemical data show that the pyroclasts are plotting in the ultrabasic and foidites. The soils of P1 and P2 show, respectively, A, Bi, C and decapitated A, C horizons; and P3 and P4 show A and C horizons. The soil profiles show a reddish and brownish clayey matrix and are friable with a plastic consistency. Their microstructures are granular, simple grain and intergrain microaggregate and, the aggregates show undifferentiated b-fabric. The mineralogical constituents of the bulk fraction are biotite, hematite, magnetite, ilmenite, pyroxene, olivine, halloysite, goethite, anatase and rutile. The clay fraction is marked by presence of halloysite, ferrihydrite and little amounts of allophane. All soils can to be classified as non-allophanic Andosols. The predominance of halloysite formed by alteration of sideromelane, suggests that allophane would be an intermediate phase of this rapid transformation favored by climate conditions of the TI. Total geochemistry showed that in all profiles Al, Fe and Ti accumulate due to their low mobility and Ca, Na, K and Mg are the most intensely leached. The profiles located at the lower quotas have higher K and Mg values in A horizon due to the influence of salt sprays and the deposition of chemical elements from the higher regions. Ti, Mn, Fe, Co, Cr, Ni, V, Zr, S were enriched in soil profiles P1 and P3 due to loss of mobile elements during the soil formation process. Zn and Cu concentrate on A horizon of profiles P3 and P4 with higher concentration of organic matter and fragments of unaltered pyroclasts. Leaching of the rare earth elements from higher to the lower slope led to the enrichment of these elements, especially the light rare earth elements, in the low-lying soil. The high-altitude profile showed Ce positive anomaly due to longer exposure to weathering.; Cette étude visait à déterminer les caractéristiques d'altération comprenant la genèse et la formation de sols sur les pyroclastes de l'Île de Trindade (IT), Atlantique Sud, Brésil. Les échantillons ont été prélevés au Vulcão do Paredão de l'Holocène (profil P1) et dans la Formation Morro Vermelho du Quaternaire ancien (profils P2, P3 et P4). Les pyroclastes de P1 et P2 sont dépôts de brèches volcaniques, tandis que P3 est un dépôt de lapilli. P4 présente des fragments de roches avec une composition minéralogique différente des autres profils suggérant un autre événement de dépôt de bombes pyroclastiques. Les éruptions associées peuvent être considérées comme stromboliennes. Analyse au microscope optique soutenue par la diffraction des rayons X indiquent un mélange de biotite, de goethite, d'ilménite, d'anatase, de magnétite, d'hématite, de pyroxènes, de zéolites et d'olivine comme minéraux principaux. La microscopie optique montre un sidéromélane qui se transforme en palagonite, indiquant une éruption phréato-magmatique. La microscopie infrarouge dans les zones palagonitisées a identifié l’halloysite, probablement issue de l'altération du sideromélane. Les amygdales et les microfractures sont partiellement ou totalement remplies de zéolites, formées par la percolation de l'eau qui réagit avec la palagonite et la précipitation des éléments chimiques du fluide hydrothermal. Les magnétites-Ti et l’iddingsite sont observées dans les fractures et en bordure des olivines. La progression de l'altération dans le profil du sol, se manifeste par la présence de reliques d'olivine ou sa transformation totale dans les horizons supérieurs, et montre que l'altération est le processus principal de formation des iddingsites. Certaines magnétites-Ti sont zonées avec un enrichissement en Cr au centre, suggérant une origine mantellique. L'augite et le diopside expliquent les teneurs élevées en éléments traces. Les données géochimiques montrent que les pyroclastes sont ultrabasique et föiditique. Les sols de P1 et P2 comportent, respectivement, les horizons A, Bi, C et un A érodé, C, tandis que P3 et P4 sont constitués des horizons A et C. Les sols montrent une matrice argileuse rougeâtre et brunâtre et sont friables avec une consistance plastique. Leurs microstructures sont granulaires, simples microaggrégats de grains et d'intergrains et, les aggrégats sont indifférenciés. Les constituants minéralogiques de la roche sont la biotite, l'hématite, la magnétite, l'ilménite, les pyroxènes, l'olivine, l'halloysite, la goethite, l'anatase et le rutile. La fraction argileuse est marquée par la présence d'halloysite, de ferrihydrite et de petites quantités d'allophane. Tous les sols peuvent être classés comme Andosols non-allophaniques. La prédominance de l'halloysite suggère que l'allophane serait une phase intermédiaire issue de l’altération rapide du sidéromélane favorisée par les conditions climatiques de l’IT. La géochimie totale montre que dans tous les profils Al, Fe et Ti s'accumulent en raison de leur faible mobilité et que Ca, Na, K et Mg sont les plus intensément lixiviés. Les profils des altitudes inférieures présentent des valeurs en K et Mg plus élevées dans l'horizon A en raison de l'influence des projections salines et de dépôt d'éléments chimiques des niveaux supérieurs. Pour P1 et P3, les éléments Ti, Mn, Fe, Co, Cr, Ni, V, Zr, S ont été enrichis dans les sols et leurs concentrations relatives sont liées à perte d'éléments mobiles pendant le processus de formation du sol. Zn et Cu se concentrent sur un horizon A de profils P3 et P4 avec une concentration plus élevée de matière organique et des fragments de pyroclastes inaltérés. Le lixiviation des terres rares de haut vers la pente inférieure a conduit à l'enrichissement de ces éléments, en particulier des terres rares légers, dans un sol à basse altitude. Le profil de haute altitude a montré une anomalie positive en Ce due à une exposition plus longue aux intempéries.

This study aimed to characterize the alteration features comprising the genesis and formation of soils on pyroclasts of Trindade Island (TI), South Atlantic, Brazil. Collections of samples were made at the Holocene Paredão volcano (Profile P1) and the Late Quartenary Morro Vermelho Formation (profiles P2, P3 and P4). The pyroclasts of P1 and P2 are volcanic breccia deposit, whereas of P3 is a lapilli deposit. P4 presents fragments of rocks with mineralogical composition different from other profiles suggesting another event of deposition of pyroclastic bombs. The eruptions associated can be regarded as strombolians. Optical microscope supported by X-ray diffraction analysis revealed a mixture of biotite, goethite, ilmenite, anatase, magnetite, hematite, pyroxene, zeolites, and olivine as their main mineral components. Petrologic analysis shows sideromelane that changes to palagonite, indicating a phreatomagmatic eruption. Infrared analyses in the palagonitized regions revealed the presence of halloysite, suggesting alteration of sideromelane to tubular clay minerals. Amygdales and microfractures are partially or totally filled with zeolites, which are formed by the percolation of water that reacts with the palagonite and precipitation of chemical elements of hydrothermal fluid. Iddingsite and Ti-magnetites occur in the fractures and edges of the olivine. The advance of the alteration towards the soil profile, leaving only relicts of olivine or reaching their total transformation in the upper horizons, shows that weathering is the main process of iddingsite formation. Some Ti-magnetites are zoned with Cr-rich core and Cr-poor edge, suggesting a mantelic origin. The augite and diopside explain the high trace elements contents. Geochemical data show that the pyroclasts are plotting in the ultrabasic and foidites. The soils of P1 and P2 show, respectively, A, Bi, C and decapitated A, C horizons; and P3 and P4 show A and C horizons. The soil profiles show a reddish and brownish clayey matrix and are friable with a plastic consistency. Their microstructures are granular, simple grain and intergrain microaggregate and, the aggregates show undifferentiated b-fabric. The mineralogical constituents of the bulk fraction are biotite, hematite, magnetite, ilmenite, pyroxene, olivine, halloysite, goethite, anatase and rutile. The clay fraction is marked by presence of halloysite, ferrihydrite and little amounts of allophane. All soils can to be classified as non-allophanic Andosols. The predominance of halloysite formed by alteration of sideromelane, suggests that allophane would be an intermediate phase of this rapid transformation favored by climate conditions of the TI. Total geochemistry showed that in all profiles Al, Fe and Ti accumulate due to their low mobility and Ca, Na, K and Mg are the most intensely leached. The profiles located at the lower quotas have higher K and Mg values in A horizon due to the influence of salt sprays and the deposition of chemical elements from the higher regions. Ti, Mn, Fe, Co, Cr, Ni, V, Zr, S were enriched in soil profiles P1 and P3 due to loss of mobile elements during the soil formation process. Zn and Cu concentrate on A horizon of profiles P3 and P4 with higher concentration of organic matter and fragments of unaltered pyroclasts. Leaching of the rare earth elements from higher to the lower slope led to the enrichment of these elements, especially the light rare earth elements, in the low-lying soil. The high-altitude profile showed Ce positive anomaly due to longer exposure to weathering.; Cette étude visait à déterminer les caractéristiques d'altération comprenant la genèse et la formation de sols sur les pyroclastes de l'Île de Trindade (IT), Atlantique Sud, Brésil. Les échantillons ont été prélevés au Vulcão do Paredão de l'Holocène (profil P1) et dans la Formation Morro Vermelho du Quaternaire ancien (profils P2, P3 et P4). Les pyroclastes de P1 et P2 sont dépôts de brèches volcaniques, tandis que P3 est un dépôt de lapilli. P4 présente des fragments de roches avec une composition minéralogique différente des autres profils suggérant un autre événement de dépôt de bombes pyroclastiques. Les éruptions associées peuvent être considérées comme stromboliennes. Analyse au microscope optique soutenue par la diffraction des rayons X indiquent un mélange de biotite, de goethite, d'ilménite, d'anatase, de magnétite, d'hématite, de pyroxènes, de zéolites et d'olivine comme minéraux principaux. La microscopie optique montre un sidéromélane qui se transforme en palagonite, indiquant une éruption phréato-magmatique. La microscopie infrarouge dans les zones palagonitisées a identifié l’halloysite, probablement issue de l'altération du sideromélane. Les amygdales et les microfractures sont partiellement ou totalement remplies de zéolites, formées par la percolation de l'eau qui réagit avec la palagonite et la précipitation des éléments chimiques du fluide hydrothermal. Les magnétites-Ti et l’iddingsite sont observées dans les fractures et en bordure des olivines. La progression de l'altération dans le profil du sol, se manifeste par la présence de reliques d'olivine ou sa transformation totale dans les horizons supérieurs, et montre que l'altération est le processus principal de formation des iddingsites. Certaines magnétites-Ti sont zonées avec un enrichissement en Cr au centre, suggérant une origine mantellique. L'augite et le diopside expliquent les teneurs élevées en éléments traces. Les données géochimiques montrent que les pyroclastes sont ultrabasique et föiditique. Les sols de P1 et P2 comportent, respectivement, les horizons A, Bi, C et un A érodé, C, tandis que P3 et P4 sont constitués des horizons A et C. Les sols montrent une matrice argileuse rougeâtre et brunâtre et sont friables avec une consistance plastique. Leurs microstructures sont granulaires, simples microaggrégats de grains et d'intergrains et, les aggrégats sont indifférenciés. Les constituants minéralogiques de la roche sont la biotite, l'hématite, la magnétite, l'ilménite, les pyroxènes, l'olivine, l'halloysite, la goethite, l'anatase et le rutile. La fraction argileuse est marquée par la présence d'halloysite, de ferrihydrite et de petites quantités d'allophane. Tous les sols peuvent être classés comme Andosols non-allophaniques. La prédominance de l'halloysite suggère que l'allophane serait une phase intermédiaire issue de l’altération rapide du sidéromélane favorisée par les conditions climatiques de l’IT. La géochimie totale montre que dans tous les profils Al, Fe et Ti s'accumulent en raison de leur faible mobilité et que Ca, Na, K et Mg sont les plus intensément lixiviés. Les profils des altitudes inférieures présentent des valeurs en K et Mg plus élevées dans l'horizon A en raison de l'influence des projections salines et de dépôt d'éléments chimiques des niveaux supérieurs. Pour P1 et P3, les éléments Ti, Mn, Fe, Co, Cr, Ni, V, Zr, S ont été enrichis dans les sols et leurs concentrations relatives sont liées à perte d'éléments mobiles pendant le processus de formation du sol. Zn et Cu se concentrent sur un horizon A de profils P3 et P4 avec une concentration plus élevée de matière organique et des fragments de pyroclastes inaltérés. Le lixiviation des terres rares de haut vers la pente inférieure a conduit à l'enrichissement de ces éléments, en particulier des terres rares légers, dans un sol à basse altitude. Le profil de haute altitude a montré une anomalie positive en Ce due à une exposition plus longue aux intempéries.

International audience; Background and Purpose: The artemisinin derivative, artemether, has antimalarial activity with potential neurotoxic and cardiotoxic effects. Artemether in nanocapsules (NC‐ATM) is more efficient than free artemether for reducing parasitaemia and increasing survival of Plasmodium berghei‐infected mice. NCs also prevent prolongation of the QT interval of the ECG. Here, we assessed cellular cardiotoxicity of artemether and how this toxicity was prevented by nanoencapsulation.Experimental Approach: Mice were treated with NC‐ATM orally (120 mg·kg−1 twice daily) for 4 days. Other mice received free artemether, blank NCs, and vehicle for comparison. We measured single‐cell contraction, intracellular Ca2+ transient using fluorescent Indo‐1AM Ca2+ dye, and electrical activity using the patch‐clamp technique in freshly isolated left ventricular myocytes. The acute effect of free artemether was also tested on cardiomyocytes of untreated animals.Key Results:Artemether prolonged action potentials (AP) upon acute exposure (at 0.1, 1, and 10 μM) of cardiomyocytes from untreated mice or after in vivo treatment. This prolongation was unrelated to blockade of K+ currents, increased Ca2+ currents or promotion of a sustained Na+ current. AP lengthening was abolished by the NCX inhibitor SEA‐0400. Artemether promoted irregular Ca2+ transients during pacing and spontaneous Ca2+ events during resting periods. NC‐ATM prevented all effects. Blank NCs had no effects compared with vehicle.Conclusion and Implications: Artemether induced NCX‐dependent AP lengthening (explaining QTc prolongation) and disrupted Ca2+ handling, both effects increasing pro‐arrhythmogenic risks. NCs prevented these adverse effects, providing a safe alternative to the use of artemether alone, especially to treat malaria.

International audience; A bioadsorbent (CEDA) capable of adsorbing As(V) and Cu(II) simultaneously was prepared by tosylation of microcrystalline cellulose (MC) and nucleophilic substitution of the tosyl group by ethylenediamine. MC, tosyl cellulose, and CEDA were characterized by elemental C, H, N, and S analysis, infrared spectroscopy, and 13C solid-state nuclear magnetic resonance spectroscopy. The adsorption of As(V) and Cu(II) on CEDA was evaluated as a function of solution pH, contact time, and initial solute concentration. The maximum adsorption capacities of CEDA for As(V) and Cu(II) were 1.62 and 1.09 mmol g−1, respectively. The interactions of As(V) and Cu(II) with CEDA were elucidated using thermodynamic parameters, molecular quantum mechanics calculations, and experiments with ion exchange of Cd(II) by Cu(II), and As(V) by SO4 2−. Adsorption enthalpies were determined as a function of surface coverage of the CEDA, using isothermal titration calorimetry, with ΔadsH° values of −32.24 ± 0.07 and −93 ± 2 kJ mol−1 obtained for As(V) and Cu(II), respectively. The potential to reuse CEDA was evaluated and the interference of other ions in the adsorption of As(V) and Cu(II) was investigated. Multi-component experiments showed that Cd(II), Co(II), Ni(II), and Pb(II) did not interfere in the adsorption of Cu(II), while SO4 2− inhibited As(V) adsorption.

The project Math & The City is a cooperation project on outdoor mathematics (math trails) and ethnomodelling between the University of Oslo and the Federal Unversity of Ouro Preto.

The term natural menopause is defined as the permanent cessation of menstruation resulting from the loss of ovarian follicular activity. Estrogen deficiency following menopause can lead to potentially pathogenic consequences such as osteoporosis, female sexual dysfunction and cardiovascular disease (CAD) risk, directly affecting women quality of life. Phytoestrogens have been reported to reduce incidence risk of breast and prostate cancers, cardiovascular disease, osteoporosis, and also lower cholesterol. Ipriflavone (IP), a derivative of naturally occurring isoflavone, has been used in the prevention and treatment of osteoporosis but, although IP has great therapeutic potential, the oral bioavailability is low due to its high lipophilicity, which limits oral absorption. In this study, a self-nanoemulsifying drug delivery system (SNEDDS) was used to load IP and the in vitro effects on cell viability were evaluated. After dilution in water, simulated gastric fluid, simulated enteric fluid or PBS, blank SNEDDS generate nanoemulsion droplets with small mean diameter, 235, 279, 1024, 210 nm, respectively and low polydispersity (PdI) indexes in water. When loading 1000 µM IP, the emulsified preparation presented, in the same order, small mean diameter of 257, 104, 866, 144 nm, which may facilitate cell uptake and possibly IP oral absorption. Cytotoxic and inhibitory concentrations for 50% of normal and cancer cells, CC50 and IC50 respectively, were determined after 24 and 96 h of treatment with IP (0.35 - 1000 µM). Ovariectomy, induced menopausal rat model, increased blood pressure (BP) with strong effect on diastolic parameter. The vasorelaxant effects of acetylcholine and of NO-donor SNP on aorta were attenuated in Ovx, in line with a reduction of NO bioavailability. There was no significant effect on cardiac morphology and systolic function evaluated by echocardiography but an increase in the Isovolumic relaxation time (IVRT) reflecting impaired diastolic function associated to Ovx-induced hypertension. Ovariectomy increased contraction of cardiomyocytes and impaired Ca2+ cycling with promotion of pro-arrhythmogenic Ca2+ events. Ipriflavone had intrinsic effects on different parameters in Sham-IP and/or Ovx-IP rats. Despite a lack of effect on BP, IP thickened the aortic wall, altered vasorelaxant responses, decreased NO bioavailability, and increased ejection fraction and IVRT in the heart. Ipriflavone also impacted single cell contraction and Ca2+ handling. Ipriflavone did not reverse effects of Ovx on BP, aortic wall remodeling, vasorelaxant properties, cardiac IVRT, but attenuated Ovx effects on resting SL, cardiomyocyte contraction and proarythmogéniques Ca2+ events. In conclusion, ipriflavone had mixed cardiovascular effects after ovariectomy in rats, principally due to intrinsic actions., Le terme ménopause naturelle est défini comme l'arrêt définitif de la menstruation résultant de la perte d'activité folliculaire ovarienne. Une carence en œstrogène après la ménopause peut avoir des conséquences potentiellement pathogènes telles que l'ostéoporose, le dysfonctionnement sexuel féminin et le risque de maladie cardiovasculaire (CAD), affectant directement la qualité de vie des femmes. Il a été signalé que les phytoestrogènes réduisent le risque d'incidence des cancers du sein et de la prostate, des maladies cardiovasculaires, de l'ostéoporose et réduisent également le cholestérol. L'ipriflavone (IP), un dérivé d'isoflavone naturelle, a été utilisé dans la prévention et le traitement de l'ostéoporose mais, bien que la IP ait un potentiel thérapeutique élevé, la biodisponibilité orale est faible en raison de sa forte lipophilie qui limite l'absorption orale. Dans cette étude, un système d'administration de médicament auto-nanoémulsifiant (SNEDDS) a été utilisé pour charger la propriété intellectuelle et les effets in vitro sur la viabilité cellulaire ont été évalués. Après dilution dans l’eau, le fluide gastrique simulé, le fluide entérique simulé ou le PBS, les SNEDDS vierges génèrent des gouttelettes de nanoémulsion de petit diamètre moyen, respectivement 235, 279, 1024, 210 nm et un faible indice de polydispersité (PdI) dans l’eau. Lors du chargement de 1000 µM IP, la préparation émulsifiée a présenté, dans le même ordre, un petit diamètre moyen de 257, 104, 866, 144 nm, ce qui pourrait faciliter l’absorption cellulaire et éventuellement l’absorption orale IP. Les concentrations cytotoxiques et inhibitrices pour 50% des cellules normales et cancéreuses, CC50 et IC50, respectivement, ont été déterminées après 24 et 96 h de traitement par IP (0,35 - 1000 µM). Ovariectomie, modèle de rat ménopausé induit, augmentation de la pression artérielle avec un effet important sur le paramètre diastolique. Les effets vasorelaxants de l'acétylcholine et du SNP donneur de NO sur l'aorte ont été atténués chez Ovx, parallèlement à une réduction de la biodisponibilité du NO. Il n'y avait pas d'effet significatif sur la morphologie cardiaque et la fonction systolique évalués par échocardiographie, mais une augmentation du temps de relaxation isovolumique reflétant une altération de la fonction diastolique associée à une hypertension induite par Ovx. L'ovariectomie a entraîné une augmentation de la contraction des cardiomyocytes et une altération du cycle du Ca2 + avec la promotion d'événements Ca2 + pro-arythmogènes. L'ipriflavone a eu des effets intrinsèques sur différents paramètres chez les rats Sham-IP et/ou Ovx-IP. En dépit d'un manque d'effet sur la pression artérielle, la IP a épaissi la paroi aortique, les réponses vasorelaxantes altérées, la biodisponibilité diminuée, et l'augmentation de la fraction d'éjection et de la IVRT dans le cœur. L'ipriflavone a également eu un impact sur la contraction des cellules individuelles et la manipulation du Ca2 +. L’Ipriflavone n’a pas inversé les effets d’Ovx sur la TA, le remodelage de la paroi aortique, les propriétés vasorelaxantes, la IVRT cardiaque, mais a atténué les effets de l’Ovx sur la SL au repos, la contraction des cardiomyocytes et les événements Ca2 + proarythmogéniques. En conclusion, l'ipriflavone a eu des effets cardiovasculaires mixtes après une ovariectomie chez le rat, principalement en raison d'actions intrinsèques.

The term natural menopause is defined as the permanent cessation of menstruation resulting from the loss of ovarian follicular activity. Estrogen deficiency following menopause can lead to potentially pathogenic consequences such as osteoporosis, female sexual dysfunction and cardiovascular disease (CAD) risk, directly affecting women quality of life. Phytoestrogens have been reported to reduce incidence risk of breast and prostate cancers, cardiovascular disease, osteoporosis, and also lower cholesterol. Ipriflavone (IP), a derivative of naturally occurring isoflavone, has been used in the prevention and treatment of osteoporosis but, although IP has great therapeutic potential, the oral bioavailability is low due to its high lipophilicity, which limits oral absorption. In this study, a self-nanoemulsifying drug delivery system (SNEDDS) was used to load IP and the in vitro effects on cell viability were evaluated. After dilution in water, simulated gastric fluid, simulated enteric fluid or PBS, blank SNEDDS generate nanoemulsion droplets with small mean diameter, 235, 279, 1024, 210 nm, respectively and low polydispersity (PdI) indexes in water. When loading 1000 µM IP, the emulsified preparation presented, in the same order, small mean diameter of 257, 104, 866, 144 nm, which may facilitate cell uptake and possibly IP oral absorption. Cytotoxic and inhibitory concentrations for 50% of normal and cancer cells, CC50 and IC50 respectively, were determined after 24 and 96 h of treatment with IP (0.35 - 1000 µM). Ovariectomy, induced menopausal rat model, increased blood pressure (BP) with strong effect on diastolic parameter. The vasorelaxant effects of acetylcholine and of NO-donor SNP on aorta were attenuated in Ovx, in line with a reduction of NO bioavailability. There was no significant effect on cardiac morphology and systolic function evaluated by echocardiography but an increase in the Isovolumic relaxation time (IVRT) reflecting impaired diastolic function associated to Ovx-induced hypertension. Ovariectomy increased contraction of cardiomyocytes and impaired Ca2+ cycling with promotion of pro-arrhythmogenic Ca2+ events. Ipriflavone had intrinsic effects on different parameters in Sham-IP and/or Ovx-IP rats. Despite a lack of effect on BP, IP thickened the aortic wall, altered vasorelaxant responses, decreased NO bioavailability, and increased ejection fraction and IVRT in the heart. Ipriflavone also impacted single cell contraction and Ca2+ handling. Ipriflavone did not reverse effects of Ovx on BP, aortic wall remodeling, vasorelaxant properties, cardiac IVRT, but attenuated Ovx effects on resting SL, cardiomyocyte contraction and proarythmogéniques Ca2+ events. In conclusion, ipriflavone had mixed cardiovascular effects after ovariectomy in rats, principally due to intrinsic actions.; Le terme ménopause naturelle est défini comme l'arrêt définitif de la menstruation résultant de la perte d'activité folliculaire ovarienne. Une carence en œstrogène après la ménopause peut avoir des conséquences potentiellement pathogènes telles que l'ostéoporose, le dysfonctionnement sexuel féminin et le risque de maladie cardiovasculaire (CAD), affectant directement la qualité de vie des femmes. Il a été signalé que les phytoestrogènes réduisent le risque d'incidence des cancers du sein et de la prostate, des maladies cardiovasculaires, de l'ostéoporose et réduisent également le cholestérol. L'ipriflavone (IP), un dérivé d'isoflavone naturelle, a été utilisé dans la prévention et le traitement de l'ostéoporose mais, bien que la IP ait un potentiel thérapeutique élevé, la biodisponibilité orale est faible en raison de sa forte lipophilie qui limite l'absorption orale. Dans cette étude, un système d'administration de médicament auto-nanoémulsifiant (SNEDDS) a été utilisé pour charger la propriété intellectuelle et les effets in vitro sur la viabilité cellulaire ont été évalués. Après dilution dans l’eau, le fluide gastrique simulé, le fluide entérique simulé ou le PBS, les SNEDDS vierges génèrent des gouttelettes de nanoémulsion de petit diamètre moyen, respectivement 235, 279, 1024, 210 nm et un faible indice de polydispersité (PdI) dans l’eau. Lors du chargement de 1000 µM IP, la préparation émulsifiée a présenté, dans le même ordre, un petit diamètre moyen de 257, 104, 866, 144 nm, ce qui pourrait faciliter l’absorption cellulaire et éventuellement l’absorption orale IP. Les concentrations cytotoxiques et inhibitrices pour 50% des cellules normales et cancéreuses, CC50 et IC50, respectivement, ont été déterminées après 24 et 96 h de traitement par IP (0,35 - 1000 µM). Ovariectomie, modèle de rat ménopausé induit, augmentation de la pression artérielle avec un effet important sur le paramètre diastolique. Les effets vasorelaxants de l'acétylcholine et du SNP donneur de NO sur l'aorte ont été atténués chez Ovx, parallèlement à une réduction de la biodisponibilité du NO. Il n'y avait pas d'effet significatif sur la morphologie cardiaque et la fonction systolique évalués par échocardiographie, mais une augmentation du temps de relaxation isovolumique reflétant une altération de la fonction diastolique associée à une hypertension induite par Ovx. L'ovariectomie a entraîné une augmentation de la contraction des cardiomyocytes et une altération du cycle du Ca2 + avec la promotion d'événements Ca2 + pro-arythmogènes. L'ipriflavone a eu des effets intrinsèques sur différents paramètres chez les rats Sham-IP et/ou Ovx-IP. En dépit d'un manque d'effet sur la pression artérielle, la IP a épaissi la paroi aortique, les réponses vasorelaxantes altérées, la biodisponibilité diminuée, et l'augmentation de la fraction d'éjection et de la IVRT dans le cœur. L'ipriflavone a également eu un impact sur la contraction des cellules individuelles et la manipulation du Ca2 +. L’Ipriflavone n’a pas inversé les effets d’Ovx sur la TA, le remodelage de la paroi aortique, les propriétés vasorelaxantes, la IVRT cardiaque, mais a atténué les effets de l’Ovx sur la SL au repos, la contraction des cardiomyocytes et les événements Ca2 + proarythmogéniques. En conclusion, l'ipriflavone a eu des effets cardiovasculaires mixtes après une ovariectomie chez le rat, principalement en raison d'actions intrinsèques.

International audience; This article introduces a novel region detector based on hierarchies of partitions, so-called Hierarchy-Based Salient Regions (HBSR). This approach enables to combine the clues given by a high quality contour detector with a custom salient region detection procedure. The evaluation of the proposed method HBSR with a standard feature detection assessment framework shows that HBSR outperforms the state-of-the-art methods, in average. These promising results may lead to improvements in many computer vision tasks.

International audience; We consider a family of rich vehicle routing problems (RVRP) which have the particularity to combine a heterogeneous fleet with other attributes, such as backhauls, multiple depots, split deliveries, site dependency, open routes, duration limits, and time windows. To efficiently solve these problems, we propose a hybrid metaheuristic which combines an iterated local search with variable neighborhood descent, for solution improvement, and a set partitioning formulation, to exploit the memory of the past search. Moreover, we investigate a class of combined neighborhoods which jointly modify the sequences of visits and perform either heuristic or optimal reassignments of vehicles to routes. To the best of our knowledge, this is the first unified approach for a large class of heterogeneous fleet RVRPs, capable of solving more than 12 problem variants. The efficiency of the algorithm is evaluated on 643 well-known benchmark instances, and 71.70% of the best known solutions are either retrieved or improved. Moreover, the proposed metaheuristic, which can be considered as a matheuristic, produces high quality solutions with low standard deviation in comparison with previous methods. Finally, we observe that the use of combined neighborhoods does not lead to significant quality gains. Contrary to intuition, the computational effort seems better spent on more intensive route optimization rather than on more intelligent and frequent fleet re-assignments.

Targeted advertising is meant to improve the efficiency of matching advertisers to their customers. However, targeted advertising can also be abused by malicious advertisers to efficiently reach people susceptible to false stories, stoke grievances, and incite social conflict. Since targeted ads are not seen by non-targeted and non-vulnerable people, malicious ads are likely to go unreported and their effects undetected. This work examines a specific case of malicious advertising, exploring the extent to which political ads from the Russian Intelligence Research Agency (IRA) run prior to 2016 U.S. elections exploited Facebook's targeted advertising infrastructure to efficiently target ads on divisive or polarizing topics (e.g., immigration, race-based policing) at vulnerable sub-populations. In particular, we do the following: (a) We conduct U.S. census-representative surveys to characterize how users with different political ideologies report, approve, and perceive truth in the content of the IRA ads. Our surveys show that many ads are "divisive": they elicit very different reactions from people belonging to different socially salient groups. (b) We characterize how these divisive ads are targeted to sub-populations that feel particularly aggrieved by the status quo. Our findings support existing calls for greater transparency of content and targeting of political ads. (c) We particularly focus on how the Facebook ad API facilitates such targeting. We show how the enormous amount of personal data Facebook aggregates about users and makes available to advertisers enables such malicious targeting., This is a preprint of a full paper accepted at ACM FAT*'19 (ACM Conference on Fairness, Accountability, and Transparency). Please cite that version instead

International audience; no abstract

International audience; Heart failure with preserved ejection fraction (HFpEF) is a common clinical syndrome associated with high morbidity and mortality. Therapeutic options are limited due to a lack of knowledge of the pathology and its evolution. We investigated the cellular phenotype and Ca2+ handling in hearts recapitulating HFpEF criteria. HFpEF was induced in a portion of male Wistar rats four weeks after abdominal aortic banding. These animals had nearly normal ejection fraction and presented elevated blood pressure, lung congestion, concentric hypertrophy, increased LV mass, wall stiffness, impaired active relaxation and passive filling of the left ventricle, enlarged left atrium, and cardiomyocyte hypertrophy. Left ventricular cell contraction was stronger and the Ca2+ transient larger. Ca2+ cycling was modified with a RyR2 mediated Ca2+ leak from the sarcoplasmic reticulum and impaired Ca2+ extrusion through the Sodium/Calcium exchanger (NCX), which promoted an increase in diastolic Ca2+. The Sarcoplasmic/endoplasmic reticulum Ca2+ ATPase (SERCA2a) and NCX protein levels were unchanged. The phospholamban (PLN) to SERCA2a ratio was augmented in favor of an inhibitory effect on the SERCA2a activity. Conversely, PLN phosphorylation at the calmodulin-dependent kinase II (CaMKII)-specific site (PLN-Thr17), which promotes SERCA2A activity, was increased as well, suggesting an adaptive compensation of Ca2+ cycling. Altogether our findings show that cardiac remodeling in hearts with a HFpEF status differs from that known for heart failure with reduced ejection fraction. These data also underscore the interdependence between systolic and diastolic "adaptations" of Ca2+ cycling with complex compensative interactions between Ca2+ handling partner and regulatory proteins.

International audience; Hierarchical image segmentation provides a region-oriented scale-space, {\em i.e.}, a set of image segmentations at different detail levels in which the segmentations at finer levels are nested with respect to those at coarser levels. However, most image segmentation algorithms, among which a graph-based image segmentation method relying on a region merging criterion was proposed by Felzenszwalb-Huttenlocher in 2004, do not lead to a hierarchy. In order to cope with a demand for hierarchical segmentation, Guimar\~aes {\em et al.} proposed in 2012 a method for hierarchizing the popular Felzenszwalb-Huttenlocher method, without providing an algorithm to compute the proposed hierarchy. This article is devoted to provide a series of algorithms to compute the result of this hierarchical graph-based image segmentation method efficiently, based mainly on two ideas: optimal dissimilarity measuring and incremental update of the hierarchical structure. Experiments show that, for an image of size 321 $\times$ 481 pixels, the most efficient algorithm produces the result in half a second whereas the most naive one requires more than four hours.

International audience; Late Cenozoic deep-sea deposits of the Bengal – Nicobar Fan recorded the events of Himalayan accretion during the India – Asia collision. IODP Expedition 362 – The Sumatra Subduction Zone – recovered a sedimentary section at the Nicobar Fan that comprises Early Miocene to Holocene strata. This work aims to identified potential sources and the evolution of the fluvial system that fed into the Nicobar Fan during that interval. For this, we analyzed zircon U-Pb-Hf in seven samples from sandy and silty turbidite deposits of U1480 and U1481 Sites. U-Pb zircon ages range from 22 to 3358 Ma and εHf −33.7 to +15, originated from Central and Eastern Himalayan, Lhasa Block, peninsular India and Indo Burma Ranges, the Ganges – Brahmaputra rivers drained areas. Our data suggest a significant reorganization of source areas since the Late Miocene. Rapid uplift of the Himalayan syntaxis in the Late Miocene to Pleistocene exposed distinct source rocks, altering the provenance signature and enhancing sediment delivery towards the sink. This is evidenced by gradually switched in first cycle zircons in the Nicobar Fan from the Lhasa Block and Gangdese Batholith to the Bomi-Chayu and Lohit Batholiths. Sediment provenance shifted since the Pliocene, with an increase in Ganges-derived Archean peninsular India, Cambro-Ordovician granites and Greater Himalaya orthogneisses at the Nicobar Fan. We attribute this shift to the rise of the Shillong Plateau, which projected the Brahmaputra delta to the west towards the Ganges river. This rise of the Shillong Plateau and the sea level fall at the Plio-Pleistocene enabled the merge of the Brahmaputra and Ganges deltas for the first time. Our data suggest that the Nicobar Fan was majorly supplied by the Brahmaputra River during the Tortonian, with an only minor contribution from the Ganges river. Following that, an increase in sediment contribution from the Ganges River is observed.

International audience; The dicynodonts are an emblematic group of herbivorous therapsids, which have survived thePermian–Triassic (PT) crisis. Laotian dicynodonts from stratigraphically well-constrained beds, using U–Pbon zircon dating, bring new insights into terrestrial faunas of Southeast Asia during the Early Triassic. Theyhave already briefly been described but their phylogenetic relationships were never been investigated. Reexaminationof the Laotian dicynodonts, three well-preserved skulls, indicates that they belong to two newspecies. Our phylogenetic analysis within Dicynodontia indicates that 1) gen. et sp. nov. 1 is closely relatedto some ”Dicynodon ”- grade taxa; and 2) gen. et sp. nov. 2 is a stem taxon to Kannemeyeriiformes. Thephylogenetic affinities of these new Laotian dicynodonts allow to discuss about the recovery of theterrestrial tetrapods during the Early Triassic: the survival of a Permian lineage across the PT crisis and/or arapid recovery with a new occurrence in the Early Triassic. The Laotian dicynodonts also shed new light onthe debated paleogeographic issues concerning the evolution of Southeast Asia from the late Paleozoic tothe early Mesozoic, particularly on the timing of the collision between the Indochina, the South China andthe North China blocks. The Early Triassic age of the two new Laotian dicynodonts, their essentiallyterrestrial lifestyle, and the phylogenetic affinities between gen. et sp. nov. 2 and Early Triassic ChineseKannemeyeriiformes, suppose a land connection between the Indochina Block and other dicynodontbearing continents as early as the Early Triassic.

International audience; Hierarchical image segmentation provides a region-oriented scale-space, i.e., a set of image segmentations at different detail levels in which the segmentations at finer levels are nested with respect to those at coarser levels. Most image segmentation algorithms, such as region merging algorithms, rely on a criterion for merging that does not lead to a hierarchy. Guimarães et al. proposed in 2012 a hierarchical graph-based image segmentation method relying on a criterion popularized by Felzenszwalb and Huttenlocher in 2004, hence hierarchizing the popular Felzenszwalb-Huttenlocher method. However, Guimarães et al. did not provide an algorithm to compute the proposed hierarchy. We propose a series of algorithms to compute the result of this hierarchical graph-based image segmentation method. For an image of size 321 × 481 pixels, the most efficient algorithm produces the result in half a second whereas the most naive one requires more than four hours

International audience; Recently, online targeted advertising platforms like Facebook have been criticized for allowing advertisers to discriminate against users belonging to sensitive groups, i.e., to exclude users belonging to a certain race or gender from receiving their ads. Such criticisms have led, for instance, Facebook to disallow the use of attributes such as ethnic affinity from being used by advertisers when targeting ads related to housing or employment or financial services. In this paper, we show that such measures are far from sufficient and that the problem of discrimination in targeted advertising is much more pernicious. We argue that discrimination measures should be based on the targeted population and not on the attributes used for targeting. We systematically investigate the different targeting methods offered by Facebook for their ability to enable discriminatory advertising. We show that a malicious advertiser can create highly discriminatory ads without using sensitive attributes. Our findings call for exploring fundamentally new methods for mitigating discrimination in online targeted advertising.

International audience; In this study, an aggregated flow formulation and a column generation strategy are proposed for the Strong Network Orientation Problem (SNOP) that consists in setting an orientation for each edge in a given graph, such that the resulting digraph is strongly connected and the total travel distance between all pairs of vertices is minimized. SNOP is NP-hard and finds application in urban networks.

International audience; The post-orogenic Yzerfontein pluton, in the Saldania Belt of South Africa was constructed through numerous injections of shoshonitic magmas. Most magma compositions are adequately modelled as products of fractionation, but the monzogranites and syenogranites may have a separate origin. A separate high-Mg mafic series has a less radiogenic mantle source. Fine-grained magmatic enclaves in the intermediate shoshonitic rocks are autoliths. The pluton was emplaced between 533 ± 3 and 537 ± 3 Ma (LA-SF-ICP-MS U–Pb zircon), essentially synchronously with many granitic magmas of the Cape Granite Suite (CGS). Yzerfontein may represent a high-level expression of the mantle heat source that initiated partial melting of the local crust and produced the CGS granitic magmas, late in the Saldanian Orogeny. However, magma mixing is not evident at emplacement level and there are no magmatic kinships with the I-type granitic rocks of the CGS. The mantle wedge is inferred to have been enriched during subduction along the active continental margin. In the late- to post-orogenic phase, the enriched mantle partially melted to produce heterogeneous magma batches, exemplified by those that formed the Yzerfontein pluton, which was further hybridised through minor assimilation of crustal materials. Like Yzerfontein, the small volumes of mafic rocks associated with many batholiths, worldwide, are probably also low-volume, high-level expressions of crustal growth through the emplacement of major amounts of mafic magma into the deep crust.

Cross-selling campaigns seek to offer the right products to the set of customers with the goal of maximizing expected profit, while, at the same time, respecting the purchasing constraints set by investors. In this context, a bi-objective version of this NP-Hard problem is approached in this paper, aiming at maximizing both the promotion campaign total profit and the risk-adjusted return, which is estimated with the reward-to-variability ratio known as Sharpe ratio. Given the combinatorial nature of the problem and the large volume of data, heuristic methods are the most common used techniques. A Greedy Randomized Neighborhood Structure is also designed, including the characteristics of a neighborhood exploration strategy together with a Greedy Randomized Constructive technique, which is embedded in a multi-objective local search metaheuristic. The latter combines the power of neighborhood exploration by using a Pareto Local Search with Variable Neighborhood Search. Sets of non-dominated solutions obtained by the proposed method are described and analyzed for a number of problem instances. The authors would like to thank Brazilian agency CAPES, CNPq (grants 305506/2010-2, 552289/2011-6, 306694/2013-1 and 312276/2013-3), FAPEMIG (grants APQ-04611-10, PPM CEX497-13) and FP7 CORDIS, “New Horizons for Multi Criteria Decision Making”, for supporting the development of this work. Helena Ramalhinho was also partially supported by the Spanish Ministry of Economy and Competitiveness (TRA2013- 48180-C3-P, TRA2015-71883-REDT).

There is evidence that diets rich in salt or simple sugars as fructose are associated with abnormalities in blood pressure regulation. However, the mechanisms underlying pathogenesis of salt- and fructose-induced kidney damage and/or consequent hypertension yet remain largely unexplored. Here, we tested the role of oxidative state as an essential factor along with high salt and fructose treatment in causing hypertension. Fischer male rats were supplemented with a high-fructose diet (20% in water) for 20 weeks and maintained on high-salt diet (8%) associate in the last 10 weeks. Fructose-fed rats exhibited a salt-dependent hypertension accompanied by decrease in renal superoxide dismutase activity, which is the first footprint of antioxidant inactivation by reactive oxygen species (ROS). Metabolic changes and the hypertensive effect of the combined fructose-salt diet (20 weeks) were markedly reversed by a superoxide scavenger, Tempol (10 mg/kg, gavage); moreover, Tempol (50 mM) potentially reduced ROS production and abolished nuclear factor-kappa B (NF-κB) activation in human embryonic kidney HEK293 cells incubated with L-fructose (30 mM) and NaCl (500 mosmol/kg added). Taken together, our data suggested a possible role of oxygen radicals and ROS-induced activation of NF-κB in the fructose- and salt-induced hypertension associated with the progression of the renal disease.

International audience; Chagas disease is a neglected parasitic disease caused by the protozoan Trypanosoma cruzi. New antitrypanosomal options are desirable to prevent complications, including a high rate of cardiomyopathy. Recently, a natural substance, lychnopholide, has shown therapeutic potential, especially when encapsulated in biodegradable polymeric nanocapsules. However, little is known regarding possible adverse effects of lychnopholide. Here we show that repeated-dose intravenous administration of free lychnopholide (2.0 mg/kg/day) for 20 days caused cardiopathy and mortality in healthy C57BL/6 mice. Echocardiography revealed concentric left ventricular hypertrophy with preserved ejection fraction, diastolic dysfunction and chamber dilatation at end-stage. Single cardiomyocytes presented altered contractility and Ca2+ handling, with spontaneous Ca2+ waves in diastole. Acute in vitro lychnopholide application on cardiomyocytes from healthy mice also induced Ca2+ handling alterations with abnormal RyR2-mediated diastolic Ca2+ release. Strikingly, the encapsulation of lychnopholide prevented the cardiac alterations induced in vivo by the free form repeated doses. Nanocapsules alone had no adverse cardiac effects. Altogether, our data establish lychnopholide presented in nanocapsule form more firmly as a promising new drug candidate to cure Chagas disease with minimal cardiotoxicity. Our study also highlights the potential of nanotechnology not only to improve the efficacy of a drug but also to protect against its adverse effects.