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International audience; Several phytoseiid species are excellent biological control agents for suppressing mite pest populations in many crops and preventing yield losses. This paper aims to improve the knowledge of Phytoseiidae diversity in citrus orchards and argan forest in central western Morocco. The surveys were conducted between April and October during three successive years (2017–2019), in nine conventional citrus orchards covering an area of more than 3,000 hectares and on uncultivated plants in argan forest at an altitude ranging from 150 to 700 meters. Twenty-nine species belonging to 15 genera were found, seven of them being new for the Moroccan fauna: Amblyseius largoensis, A. swirskii, Amblyseiella setosa, Euseius batus, E. dossei, Paragigagnathus molestus, and Cydnoseius negevi. Species of nine genera were found on citrus leaves: Neoseiulus, Amblyseius, Amblyseiella, Transeius, Phytoseiulus, Euseius, Phytoseius, Typhlodromus, and Paraseiulus. Stah AlMadina (24.8%), Ouled Abdellah (15.9%), Nour (14.3%) domains contained a high number (more than 60.2%) of individuals in the collected samples. Malva parviflora, Convolvulus althaeoides, Solanum nigrum, Bryonia dioica, Withania somnifera would be interesting companion plants to be associated in the inter-rows in citrus orchards in this region to ensure sustainability, because they host high densities and diversities of Phytoseiidae. A key of females of all recorded Moroccan species until now is provided.

International audience

The work presented in this thesis is part of a broader issue of Adaptive Learning System (ALS). He is particularly interested in Dynamic Adaptive Hypermedia Systems (DAHS). The main purpose is to examine the advantage of the fine-grained approach to adapt the course in these systems. In fact, it deals with automatic generation of courses tailored to a particular student, based on a set of educational resources and according to their needs, preferences and prerequisites. Learning resources called learning objects are currently indexed using metadata standards and educational standards as SCORM and LOM. These learning objects are assembled and associated to form individual training with a hypermedia presentation. We propose a new approach for the learning object granularity based on size, content and the media used. This approach provides a breakdown of content in fragments, which may be in different forms such as Introduction, definition, example, comment, etc. Each of these fragments is represented by multimedia bricks like text, image, video, sound, etc. All these elements are used to improve adaptability, in content, presentation and navigation in a hypermedia learning environment. In summary, based on a set of basic and granular resources, their semantic descriptions and the learner profile, the system expected to be able to generate adequate courses (courses, exercises, etc.) with a Web browsing interface. In this sense we have established the first brick of DAHS, which we call Adaptive Learning System for the"C" Programming Language (ALS-CPL). This particular system aims first to implement our research in programming learning environments as part of a broader project entitled Adaptive Learning System for Programming Languages (ALS-PL). It also aims to apply particularly the granular content approach for adaptability.; Le travail que nous présentons dans cette thèse s'intègre dans une problématique générale des Environnements Informatiques pour l'Apprentissage Humain (EIAH). Il s'intéresse plus particulièrement aux Systèmes Hypermédias Adaptatifs Dynamiques (SHAD). Le but principal est d'examiner l'intérêt de la granularité fine pour l'adaptation des parcours dans ces systèmes. Il s'agit, en fait, de la génération automatique de cours adaptés à un apprenant particulier, à partir d'un ensemble de ressources pédagogiques et en fonction de ses besoins, ses préférences et ses pré-requis. Les ressources pédagogiques appelés actuellement objets pédagogiques sont indexés en utilisant des normes et des standards de métadonnées éducatifs comme LOM et SCORM. Ces objets pédagogiques, qui constituent le contenu à apprendre, sont assemblés à partir de grains pédagogiques puis associées pour constituer des parcours individuels de formation avec une présentation de type hypermédia. Nous proposons dans le cadre de ce travail, une nouvelle approche de la granularité des ressources pédagogiques basée sur la taille, le contenu et le type de média utilisé. Cette modélisation granulaire propose une décomposition du contenu en fragments ou grains pédagogiques de type introduction, définition, exemple, remarque, etc. Chacun de ces fragments est représenté par des briques multimédia de type : texte, image, son, vidéo, etc. Tous ces éléments servent à améliorer l'adaptabilité, à la fois du contenu, de sa présentation et de la navigation dans un environnement d'apprentissage hypermédia. En résumé, à partir d'un ensemble de ressources élémentaires et granulaires, de leurs descriptions sémantiques et du profil de l'apprenant, le système attendu doit être capable de générer des ressources adaptées (cours, exercices, etc.) avec une interface de navigation sur le Web. Dans ce sens nous avons mis en place les premières briques de réalisation d'un SHAD, que nous avons baptisé Adaptive Learning System for the "C" Programming Language (ALS-CPL). Ce système spécifique vise tout d'abord à mettre en application nos recherches sur les environnements d'apprentissage de programmation, dans le cadre d'un large projet intitulé Adaptive Learning System for Programming Languages (ALS-PL). Il a également pour but particulier de mettre en pratique l'approche granulaire des contenus pour l'adaptabilité.

The work presented in this thesis is part of a broader issue of Adaptive Learning System (ALS). He is particularly interested in Dynamic Adaptive Hypermedia Systems (DAHS). The main purpose is to examine the advantage of the fine-grained approach to adapt the course in these systems. In fact, it deals with automatic generation of courses tailored to a particular student, based on a set of educational resources and according to their needs, preferences and prerequisites. Learning resources called learning objects are currently indexed using metadata standards and educational standards as SCORM and LOM. These learning objects are assembled and associated to form individual training with a hypermedia presentation. We propose a new approach for the learning object granularity based on size, content and the media used. This approach provides a breakdown of content in fragments, which may be in different forms such as Introduction, definition, example, comment, etc. Each of these fragments is represented by multimedia bricks like text, image, video, sound, etc. All these elements are used to improve adaptability, in content, presentation and navigation in a hypermedia learning environment. In summary, based on a set of basic and granular resources, their semantic descriptions and the learner profile, the system expected to be able to generate adequate courses (courses, exercises, etc.) with a Web browsing interface. In this sense we have established the first brick of DAHS, which we call Adaptive Learning System for the"C" Programming Language (ALS-CPL). This particular system aims first to implement our research in programming learning environments as part of a broader project entitled Adaptive Learning System for Programming Languages (ALS-PL). It also aims to apply particularly the granular content approach for adaptability., Le travail que nous présentons dans cette thèse s'intègre dans une problématique générale des Environnements Informatiques pour l'Apprentissage Humain (EIAH). Il s'intéresse plus particulièrement aux Systèmes Hypermédias Adaptatifs Dynamiques (SHAD). Le but principal est d'examiner l'intérêt de la granularité fine pour l'adaptation des parcours dans ces systèmes. Il s'agit, en fait, de la génération automatique de cours adaptés à un apprenant particulier, à partir d'un ensemble de ressources pédagogiques et en fonction de ses besoins, ses préférences et ses pré-requis. Les ressources pédagogiques appelés actuellement objets pédagogiques sont indexés en utilisant des normes et des standards de métadonnées éducatifs comme LOM et SCORM. Ces objets pédagogiques, qui constituent le contenu à apprendre, sont assemblés à partir de grains pédagogiques puis associées pour constituer des parcours individuels de formation avec une présentation de type hypermédia. Nous proposons dans le cadre de ce travail, une nouvelle approche de la granularité des ressources pédagogiques basée sur la taille, le contenu et le type de média utilisé. Cette modélisation granulaire propose une décomposition du contenu en fragments ou grains pédagogiques de type introduction, définition, exemple, remarque, etc. Chacun de ces fragments est représenté par des briques multimédia de type : texte, image, son, vidéo, etc. Tous ces éléments servent à améliorer l'adaptabilité, à la fois du contenu, de sa présentation et de la navigation dans un environnement d'apprentissage hypermédia. En résumé, à partir d'un ensemble de ressources élémentaires et granulaires, de leurs descriptions sémantiques et du profil de l'apprenant, le système attendu doit être capable de générer des ressources adaptées (cours, exercices, etc.) avec une interface de navigation sur le Web. Dans ce sens nous avons mis en place les premières briques de réalisation d'un SHAD, que nous avons baptisé Adaptive Learning System for the "C" Programming Language (ALS-CPL). Ce système spécifique vise tout d'abord à mettre en application nos recherches sur les environnements d'apprentissage de programmation, dans le cadre d'un large projet intitulé Adaptive Learning System for Programming Languages (ALS-PL). Il a également pour but particulier de mettre en pratique l'approche granulaire des contenus pour l'adaptabilité.

International audience

International audience

International audience; In the recent years, exceptional fossil sites have revealed astonishing details on the anatomy, lifestyles and behaviour of Cambrian animals but surprisingly, very little is known about one of their most vital features, reproduction. We describe here in situ eggs (clusters of 3 to 30 oocytes) in the tube-dwelling priapulid worm Paraselkirkia sinica from the Cambrian Stage 3 Xiaoshiba Lagerstätte (ca. 514 Ma, South China). These oocytes were accommodated within paired tubular ovaries located in the posterior half of the primary body cavity as in modern meiobenthic priapulid worms, thus indicating that the general organization of female tubular gonads in priapulid worms has remained virtually unchanged for half a billion years. Our findings provide for the first time, key information on the reproductive organs and strategies of early ecdysozoans, a huge animal clade that dominated Cambrian marine ecosystems and accounts for a large part of today's biodiversity (e.g. arthropods). Moreover, we also emphasize the critical role of ecology on the reproductive strategies and lifestyles of both modern and Cambrian worms.

For the purpose of achieving sustainable development in the context of a changing climate, the development and implementation of tripartite cooperation tools, into a transatlantic cooperation framework, is the crux of a project to bring about a transdisciplinary platform focused on research, technology, and innovation in drylands. It finds its roots in the Agadir Declaration of May 2016. The objective of the platform is to set up a 'hub or rear base' at the University of Ibn Zohr in Agadir to develop transdisciplinary research and training mechanisms on climate change and its impacts on the functioning of ecosystems and their goods and ser-vices in arid and semiarid regions. Currently, the main challenge to achieve sus-tainable development resides in ensuring that decision-making processes are supported by science. How to translate scientific knowledge on complex long-term issues at the national, cross-regional, and transatlantic scale into better informed public policy remains an open question for multi-sectoral partnerships. The main thread underlying this chapter relates to the establishment of interface models between science and policy: what challenges will the Agadir Platform assume to bridge various forms of interdisciplinary science and policy expertise to inform decision- makers on long-term wicked problems related to drylands socio-ecological systems ?

International audience; In this paper, a simple home-made Forcespinning system was designed and successfully applied for the production of different metal oxide ultrafine tubes such as SnOx and ZnO. The morphology, purity, crystallinity and porosity of the forcespun samples were investigated by SEM, XRD, and EDS, TGA, and BET analysis. The samples were deposited unto a microsensing platform and their gas-sensing properties against different hazardous vapors such as ethanol, acetone and benzene were studied through preliminary tests at different detection temperatures. The results revealed different sensing behaviors of the prepared sensors towards the different vapors. Interestingly, the gas sensor based on SnO x exhibited a higher and faster sensor response towards ethanol at 180°C as operating temperature. On the other hand, ZnO presented a higher response to acetone at 250°C. The ability of the prepared sensors to discriminate between the different vapors was explored.

International audience; abstract simple

The Imiter inlier (eastern part of the Moroccan Anti-Atlas) is located on the northwestern border of the West African Craton (WAC) and exhibits a range of Pan-African granitoids. Three massifs that crosscut the Imiter Saghro Group were targeted in this work: the Igoudrane granodiorite, Bou Teglimt granodiorite and Bou Fliou granite. We present here additional geochemical analyses (major and trace elements) and Sm-Nd isotopic data, which define two distinct groups: (i) the Igoudrane massif (677 Ma) and (ii) the Bou Teglimt granodiorite (576 Ma) and the Bou Fliou granite (550 Ma). Geochemical data confirm the calc-alkaline signature of the studied granitoids. Both groups of granitoids are slightly peraluminous and show strong negative anomalies in Nb, Ta and Ti in multi-element plots normalized to the primitive mantle. The granitoids have low 143 Nd/ 144 Nd initial ratios (0.5116–0.5117), with T DM model ages ranging from 1.73 to 1.52Ga. The eNd (t) values are negative, decreasing from the Igoudrane samples (−1.1 to −3.1) to the Bou Teglimt granodiorite (−3.0 to −3.3) and Bou Fliou (−4.2 to −4.8). All these data suggest a mixed magmatic origin involving a juvenile mantle source and an old, at least Paleoproterozoic crust. Given Mesoproterozoic rocks are lacking or very scarce in the Anti-Atlas, these results confirm the existence of an old cratonic basement beneath the eastern Anti-Atlas, and therefore suggest that the northern border of the West African Craton must be placed further to the north, as suggested by previous work in this region.

International audience; The Taghdout Group is a passive margin sequence deposited during rifting and break-up of the northern margin of the West African craton (WAC), culminating with the creation of an oceanic basin between the northern edge of the WAC and an unknown terrane. However, the age of this passive margin has been poorly constrained. It was previously thought to be c. 800–1000 Ma on the basis of age of the contact metamorphosed host rocks of the associated mafic dykes (Rb/Sr, 789 ± 10 Ma). However, with the U-Pb dating of numerous dyke swarms in the Anti-Atlas Inliers, at c. 870, 1416-1380, 1650, 1750, and 2040 Ma, it was suggested by Youbi et al. (2013) that the Taghdout Group could be Mesoproterozoic in age, with a preference for an age of 1750 Ma. In order to test this idea, a mafic sill within the Taghdout Group has been dated by the ID-TIMS U-Pb method on baddeleyite, yielding an approximate age of c. 1710 Ma. This preliminary age confirms that the Taghdout Group is much older than previously thought. Further geochronology work is required to determine whether this c. 1710 Ma age represents a new intraplate event in the WAC or whether more concordant data could yield an age closer to the known WAC LIP event of c. 1750 Ma. With this result we propose a new lithostratigraphic framework for the Proterorozoic in the Anti-Atlas.

This study presents new U–Pb zircon ages for three granitoid bodies in the Imiter inlier at the eastern part of the Moroccan Anti-Atlas chain, which is located in the northwestern edge of the West African Craton (WAC). Analyzes of zircon grains yield the following ages: 538 ± 6 and 575 ± 10 Ma for the Igoudrane massif , 567 ± 6 Ma for the nearby Bou Teglimt granodiorite , and 582 ± 6 Ma for the Bou Fliou granite . These new data reveal that the Igoudrane massif is younger than previously thought (677 Ma), and that all the granitoids in the Imiter area are Ediacaran in age and are related to the Ouarzazate Group. Sm-Nd isotopic data yield negative eNd(t) values (−4.5 to −0.2) and T DM model ages of 1.04–1.82 Ga. These data indicate the presence of an inherited Paleoproterozoic to Archaean component in some zircon grains and show that generation of the parent magmas involved a Neoproterozoic juvenile contribution and recycling of an older crustal component. These new data allow reinterpreting the geochemical and isotopic data of the granitoids, and revisiting the structural significance to the Igoudrane massif, which was assumed until now to be coeval with the major Pan-African event of the Central Anti-Atlas. They also bring significant constraints to discuss the context and age of deposition of the Saghro Group, which is still a matter of debate. All these data provide evidence of an emplacement of the Imiter granitoids in a subduction complex, which affected all of the Anti-Atlas chain during the Late Proterozoic time.

International audience; Belonging to the huge Ouarzazate volcanic Group that covered the whole Anti-Atlas during the late Ediacaran (580-545 Ma), the Tifnoute valley volcanic formations are mainly pyroclastic and show a large composition, from trachybasalt to rhyolite and are crosscut by dolerite dykes. The Tifnoute valley volcanic rocks are located within a rigid salient of the Anti-Atlas that gives them special extreme characteristics. Due to the heavy greenschist alteration that affects this volcanic group, we focused the more immobile elements, but as REE can also be affected, we used the composition of unaltered clinopyroxene crystals to determine the nature of these volcanic rocks. The clinopyroxene is an augite diopside in the basalt, an augite in the andesite and an augite-salite in the dolerite. Petrography of the Tifnoute mafic volcanic rocks and clinopyroxene compositions indicate the presence of two magmatic series: (i) older high-K calc-alkaline (alkali-calcic) andesite and basalt characterized by the early crystallization of Fe-Ti oxides and of the late fractionation of plagioclase, the modal proportion of the latter increasing from the basalt to the andesite and (ii) younger alkalic dolerite dykes. With clinopyroxene trace element compositions obtained using laser ablation ICP-MS, we calculated the composition of the melts in equilibrium with the pyroxenes.The volcanic rocks of the Tifnoute Valley have positive εNd570 (+1.7 to +5.0), low Sri (

International audience; We welcome the comment by Michard et al. (2013) as it gives us the opportunity to better discuss the Jurassic–Cretaceous magmatism of the High Atlas (Morocco). In their comment, Michard et al. (2013) focus on three main points which are: (i) the age of the basalts from Naour, (ii) the structural history of the Central High Atlas and (iii) the geodynamic significance of the related Jurassic–Cretaceous magmatism. We will address these questions in the following sections.

The aim of this paper is to predict in details the distributed nocturnal climate inside a one hectare Moroccan canary type tomato-greenhouse equipped with continuous roof and sidewalls ventilation openings with fine insect screens, by means of 3D CFD (Computational Fluid Dynamics) simulations by using a commercial Software package CFD2000 based on the finite volumes method to solve the mass, momentum and energy conservation equations. The turbulent transfers were described by a k-e model. Likewise, the dynamic influences of insect screens and tomato crop on airflow movement were modeled by means of the concept of porous medium with the Boussinesq assumption. Atmospheric radiations contribution was included in the model by customising the plastic roof cover temperature deducted from its energy balance. Also, the CFD code was customized in order to simulate in each element of the crop cover the sensible and latent heat exchanges between the greenhouse air and tomato crop. Simulations were carried out with a wind prevailing direction perpendicular to the roof openings (west-east direction). Simulations were later validated with respect to temperature and specific humidity field measurements inside the experimental greenhouse. Also, the model was verified respect to global sensible and latent heat transfers. Results show that, generally, greenhouse nocturnal climate distribution is homogeneous along the studies greenhouse area. The insect proof significantly reduced inside airflow wind speed. But there is no significant effect on the inside air temperature and specific humidity respect to outside.

Summary Two coastal sites were investigated in an arid region of southwest Morocco to determine the amount of dew, fog and rain that could be collected from rooftops for household use. Systematic measurements were performed in Mirleft (43 m asl, 200 m from the coast) for 1 year (May 1, 2007 to April 30, 2008) and in Id Ouasskssou (240 m asl, 8 km from the coast) for three summer months (July 1, 2007 to September 30, 2007). Dew water was collected using standard passive dew condensers and fog water by utilizing planar fog collectors. The wind flow was simulated on the rooftop to establish the location of the fog collector. At both sites, dew yields and, to a lesser extent, fog water yields, were found to be significant in comparison to rain events. Mirleft had 178 dew events (48.6% of the year, 18 ± 2 L m −2 cumulated amount) and 20 fog episodes (5.5% of the year, 1.4 L m −2 with uncertainty −0.2/+0.4 L m −2 cumulated amount), corresponding to almost 40% of the yearly rain contribution (31 rain events, 8.5% of the year, 49 ± 7 mm cumulated amount). At Id Ouasskssou there were 50 dew events (7.1 ± 0.3 L m −2 , 54.3% frequency), 16 fog events (6.5 L m −2 with uncertainty −0.1/+1.8 L m −2 , 17.4% frequency) and six rain events (16 ± 2 mm, 6.5% frequency). Meteorological data (air and dew point temperature and/or relative humidity, wind speed and wind direction, cloud cover) were recorded continuously at Mirleft to assess the influence of local meteorological conditions on dew and fog formation. Using the set of collected data, a new model for dew yield prediction based on artificial neural networks was developed and tested for the Mirleft site. This model was then extrapolated to 15 major cities in Morocco to assess their potential for dew water collection. It was found that the location of the cities with respect to the Atlas mountain chain, which controls the circulation of the humid marine air, is the main factor that influences dew production.

International audience; By extrapolation of the extensive use of cyclodextrin (CD)-modified materials in chromatography techniques, we study CD-containing membranes as contactors having facilitated transport properties in liquid/liquid extraction. Our main interest lies in the understanding and modelling of the mass transport mechanism for the development of pertraction applications using these membranes. The sorption and diffusion processes of xylenes as model molecules were studied through sorption experiments in membranes containing alpha-CD. The presence of highly pronounced induction times on sorption curves makes it impossible to use standard models, like the solution-diffusion one, to describe the experimental data. A generalized dual mode model has therefore been developed to account for three distinct regimes of strong facilitated transport membranes: (i) one controlled by diffusion within a membrane, (ii) one controlled by a kinetic retardation of solute entry into and out of a membrane, and (iii) one controlled by the kinetics of complexation formation. The permeant species are divided into two populations: one diffusing in the membrane and one forming immobile inclusion complexes with fixed CD sites. The model fits, which agree well with the experimental data using a limited number of adjustable parameters, indicate that the kinetics of interfacial transfer depends on the CD content.

The interactions between a greenhouse banana crop and the surrounding environment were investigated within a large-scale type of greenhouse. This investigation took place through a whole development cycle of a mature banana crop in the region of Rabat, Morocco. Two measurement series are presented: the first from 4 to 9 March 1998 is representative of the Spring and Autumn conditions; the second which extends from 6 to 26 July 1999 is representative of the Summer period. Space- and time-dependent air evolution (the evolution of air temperature in time (time course) and space (vertically at trees levels in the greenhouse)) leaf temperature and air humidity were analysed, and evidence was provided for the significant oasis effect generated by the crop in the greenhouse. In addition, leaf area and stomatal resistance measurements are analysed and discussed. With regard to the function of microclimate-dependent parameters, a model of leaf stomatal resistance was additionally defined and developed. The transpiration model of the banana crop under cover was validated with respect to the estimated rates of heat and mass transfer implied from indoor and outdoor climatic measurements.

Natural ventilation performance is one of the key climate control parameters for Canary type greenhouses, which are rapidly expanding along the Atlantic coast in Morocco. The use of insect screens significantly reduces airflow and increases thermal gradients inside the greenhouse. The aim of this study was to analyze the natural ventilation performances in real cultural conditions of a large-scale Canary type tomato greenhouse (1.1 ha) equipped with insect screens on the vent openings. A global energy balance of the greenhouse was used, allowing for the determination of air exchange rates. The greenhouse ventilation performance was compared with those of other greenhouses types and discussed with respect to the improvement of greenhouse vent design, insect screen types, and ridge and crop row orientation. The results confirm the strong dependence of greenhouse ventilation rate on wind speed and ventilation opening location. In addition, results show a significant reduction of the ventilation rate compared with other greenhouse types: the insect screen reduced the greenhouse ventilation rate by 46%, and the tomato rows that were oriented perpendicular to the prevailing air movement through the greenhouse reduced the ventilation rate by 50%. From this analysis, practical improvements are proposed and discussed in the context of protected crop production in the coastal area of Morocco.

[60]Fullerene, entrapped in a thin polymer film synthesized by oxidative electropolymerization on a layer of an amphiphilic pyrrole derivative mixed with the fullerene and coated onto an electron-conducting substrate, was shown to play the role of a modified photoelectrode. The photocurrents obtained upon irradiation with visible light in the presence of a water soluble electron donor were shown to be very sensitive to the presence of oxygen in the vicinity of the modified electrode, especially at low oxygen concentrations. This behaviour is explained by the competition between the deactivation of the photoexcited states of [60]fullerene by electron transfer from the donor and by energy transfer to molecular oxygen. This basic principle for the design of a new oxygen sensor is discussed.

International audience; Basaltic lava flows, dykes and sills, interbedded within red clastic continental sedimentary sequences (the so called "Couches Rouges") are widespread in the Oued El-Abid syncline. They represent the best candidates to study the Jurassic-Cretaceous magmatism in the Moroccan High Atlas. The volcanic successions were formed during two pulses of volcanic activity, represented by the Middle to Upper Jurassic basaltic sequence B1 (1-4 eruptions) and the Lower Cretaceous basaltic sequence B2 (three eruptions). Whether belonging to the B1 or B2, the lava flows present morphology and internal structures typical of inflated pahoehoe. Our geochemical data show that, at least for Jurassic magmatism, the dykes, and sills cannot be considered as strictly representing the feeders of the sampled lava flows. The Middle to Upper Jurassic pulse is moderately alkaline in character, while the Lower Cretaceous one is transitional. Crustal contamination plays a minor role in the petrogenesis of these magmas, which were generated by variable partial melting degrees of a garnet-bearing mantle source. Magmatism location was controlled by pre-existing Hercynian fault systems reactivated during a Middle to Upper Jurassic-Cretaceous rifting event. The associated lithospheric stretching induced melting, by adiabatic decompression, of enriched low-solidus infra-lithospheric domains.

The photoelectrochemical properties of C 60 entrapped in thin, functionalized polypyrrole films coated on indium-tin oxide (ITO) electrodes have been examined. A stable photocurrent is observed in the presence of an irreversible electron donor (ascorbic acid) in solution. Results suggest the coexistence of monomers and aggregates of C 60 in the polymeric matrix.

International audience; In the Tifnoute Valley, three plutonic units have been defined: the Askaoun intrusion, the Imourkhssen intrusion and the Ougougane group of small intrusions. They are made of quartz diorite, granodiorite and granite and all contain abundant mafic microgranular enclaves (MME). The Askaoun granodiorite and the Imourkhssen granite have been dated by LA-ICP-MS on zircon at 558 ± 2 Ma and 561 ± 3 Ma, respectively. These granitic intrusions are subcontemporaneous to the widespread volcanic and volcano-detrital rocks from the Ouarzazate Group (580-545 Ma), marking the post-collisional transtensional period in the Anti-Atlas and which evolved towards alkaline and tholeiitic lavas in minor volume at the beginning of the Cambrian anorogenic intraplate extensional period. Geochemically, the Tifnoute Valley granitoids belong to an alkali-calcic series (high-K calc-alkaline) with typical Nb-Ta negative anomalies and no alkaline affinities. Granitoids and enclaves display positive εNd-560Ma (+0.8 to +3.5) with young Nd-TDM between 800 and 1200 Ma and relatively low 87Sr/86Sr initial ratios (Sri: 0.7034 and 0.7065). These values indicate a mainly juvenile source corresponding to a Pan-African metasomatized lithospheric mantle partly mixed with an old crustal component from the underlying West African Craton (WAC). Preservation in the Anti-Atlas of pre-Pan-African lithologies (c. 2.03 Ga basement, c. 800 Ma passive margin greenschist-facies sediments, allochthonous 750-700 Ma ophiolitic sequences) indicates that the Anti-Atlas lithosphere has not been thickened and was never an active margin during the Neoproterozoic. After a transpressive period, the late Ediacaran period (580-545 Ma) is marked by movement on near vertical transtensional faults, synchronous with the emplacement of the huge Ouarzazate Group and the Tifnoute Valley granitoids. We propose here a geodynamical model where the Tifnoute Valley granitoids as well as the Ouarzazate Group were generated during the post-collisional metacratonic evolution of the northern boundary of the West African craton. The convergence with the peri-Gondwanan active margin produced brittle fracturing of the cratonic boundary without thickening, allowing rising of magmas. The Tifnoute Valley granitoids display a metasomatized lithospheric mantle source mixed with a minor ancient (2 Ga) continental crust component from the underlying WAC.

International audience; In this article the results of measurement in near-field concerning a 16-bit microcontroller from Freescale are reported, with and without a film of ferromagnetic material (Permalloy) plated against the surface of its package. This material improves near-field electromagnetic compatibility performances by reducing, in good proportion, the parasitic emission.

Polymer membranes containing α-cyclodextrin (α-CD) were prepared by the casting method using cross-linking reaction with hexamethylenediisocyanate. The film synthesis conducted with and without dibutyltin dilaurate as catalyst, resulted in two series of materials in which α-CD host entities were chemically linked to polyvinyl alcohol and physically entrapped, respectively. The obtained membranes were successfully applied to the separation of o -/ p - and o -/ m -xylene isomer mixtures by pertraction from water. p - and m -xylenes were found to be the faster permeants compared to the o -isomer. The separation factor of p -xylene over o -xylene varied from 7.75 to 0.35 depending on the membrane α-CD content and the feed concentration ratio. Permeation rate and separation selectivity data were discussed in terms of molecular recognition by α-CD and of coupling transport effect. Both kinds of materials showed similar behaviour in their permeation performances indicating that inclusion interaction was not changed by the chemical grafting on PVA chains.

Tobacco smoke is recognized as an addiction that is comparable to all other addictions : alcohol, opioide and psychoactive drugs addictions. The mechanisms responsible for the initiation and maintain of addictions are also implicated in other forms of human behavior deviations, like feeding deviations, compulsion .... Nicotine from tobacco leaf is very toxic, once absorbed, it reaches the brain and anywhere in the body, activates its receptors and produce toxic effects and homeostatic adaptations. The importance of its effects will depend on dose, mode of administration, chronicity, the effect being considered, the genome considered and its interactions with its main derivative, cotinine. Cotinine results from the addition of an oxygen atom to the α position of the pyrrolidine ring. The consequences of this conversion has been evaluated, in the present study, starting from the chemical structure of these alkaloids to the isolation of biochemical, neurochemical, molecular and behavioral mechanisms of their actions. These distinct mechanisms were validated through an integrative study, pointing on possible contribution of nitric oxide as a modulator of tobacco smoke dependence, in agreement with results of the literature study implying this neuromediator in all forms of dependence. The mechanism sustaining predisposition, the initiation and the reasons for the evolution toward dependence and relapses are currently investigated. The works in these fields suggest that modifications of certain proteins propagate long term signals and that reactive oxygen and nitrogen species are behind the mechanisms of long term potentiation and depression. Our work shows that cotinine is not toxic [422,423], is a pure psychoactive drug [414], with a novel non nicotinic pharmacological profile [416,417,419,422,423], is transported into brain [415], and its transport in regulated through peripheral nicotinic acetylcholine receptors [412,421], shows the endogenous and exogenous forms of cotinine [424], the cotinine receptor mediation of anti stress activity [420] and its homology to human proteins implicated in inflammatory reactions [36,161], paracrine stimulation of cell growth [55], dopamine release and the production of lipid peroxydation by cotinine administration [418], reinforcement in flexible approaches, the participation of emotional states and anxiety to anxiolytic response of the administration and anxiogenic response of withdrawal. They permit to propose that nicotine acts directly and indirectly through its conversion to cotinine. The later acts principally through its receptors, in brain through p40, to modulate dopamine release with consequence on learning, reward, oxidative stress, anxiety and long term potentiation and depression responses. As a conclusion, our work has permitted to propose novel pharmacological targets, methods and concepts in attempt to unify biochemical, neurochemical, molecular and behavioral mechanisms of addiction, hoping that these knowledge will be used to understand differences in susceptibility and to develop novel approaches for prevention and treatment., Le tabagisme est reconnu comme une dépendance comparable aux autres dépendances : alcool, opiacées et autres psycho-stimulants. Les mécanismes responsables de l'initiation et du maintien de l'addiction sont également impliqués dans les déviations comportementales en général, comme les déviations nutritionnelles, les compulsions.... La nicotine de la feuille de tabac est très toxique, dès son absorption, elle atteint le cerveau et tout l'organisme, active ses récepteurs et produit des effets toxiques et des adaptations homéostatiques. L'importance de ses effets va dépendre de la dose, du mode d'administration, de la chronicité, de l'effet considéré, du génome considéré et des interactions avec son principal dérivé, la cotinine. La cotinine résulte de l'addition d'un atome d'oxygène en position α du noyau pyrrolidine. Les conséquences de cette métabolisation ont été évaluées, dans l'étude présente, en partant des structures chimiques de ces deux alcaloïdes jusqu'à l'isolement des mécanismes biochimiques, neurochimiques, moléculaires et comportementaux de leurs actions. Ces différents mécanismes ont été validés par une étude intégrative en pointant le monoxyde d'azote NO comme un médiateur de la dépendance tabagique, en accord avec les données de l'étude bibliographique qui impliquent ce même médiateur dans toutes les dépendances. Les mécanismes à la base des prédispositions, le début et les raisons de l'évolution vers un état dépendant et les raisons des rechutes font l'objet d'intenses investigations. Les travaux dans ce domaine suggèrent que certaines modifications des protéines transmettent un signal de longue durée et que les espèces réactives de l'oxygène et du nitrogène sont à la base des mécanismes de potentialisation et de dépression à long terme. Notre travail montre une absence de toxicité pour la cotinine [422,423], une activité psychostimulante pure [414], une pharmacologie nouvelle non nicotinique [416,417,419,422,423], un passage actif [415] dans le cerveau régulé par le système nicotinique périphérique [412,421], la forme endogène et exogène de la cotinine [424], la médiation d'activité anti stress du récepteur p40 de la cotinine [420] et son homologie avec les protéines humaines impliquées dans les réactions inflammatoires [36,161], stimulatrice paracrine de la croissance cellulaire [55], un rôle dans la libération de dopamine, la production d'un stress oxydant par l'administration de la cotinine [418], un renforcement dans le contexte des approches flexibles, la participation forte des états émotionnels et d'anxiété à l'action anxiolytique de l'administration et anxiogène du retrait de la cotinine. Ils permettent de proposer que la nicotine agit directement et indirectement par sa conversion en cotinine. Cette dernière agit par ses récepteurs, au niveau central par la p40, pour moduler les taux de dopamine avec des conséquences sur l'apprentissage, la récompense, le stress oxydatif, l'anxiété et les réponses potentialisées et déprimées à long terme. Comme conclusion, nos travaux permettent de proposer de nouvelles cibles pharmacologiques, méthodes et concepts permettant de comprendre à l'échelle biochimique, neurochimique, moléculaire et comportemental l'addiction tabagique. L'espoir est d'utiliser ces connaissances pour différencier les susceptibilités et développer de nouvelles approches préventives et thérapeutiques.

Tobacco smoke is recognized as an addiction that is comparable to all other addictions : alcohol, opioide and psychoactive drugs addictions. The mechanisms responsible for the initiation and maintain of addictions are also implicated in other forms of human behavior deviations, like feeding deviations, compulsion .... Nicotine from tobacco leaf is very toxic, once absorbed, it reaches the brain and anywhere in the body, activates its receptors and produce toxic effects and homeostatic adaptations. The importance of its effects will depend on dose, mode of administration, chronicity, the effect being considered, the genome considered and its interactions with its main derivative, cotinine. Cotinine results from the addition of an oxygen atom to the α position of the pyrrolidine ring. The consequences of this conversion has been evaluated, in the present study, starting from the chemical structure of these alkaloids to the isolation of biochemical, neurochemical, molecular and behavioral mechanisms of their actions. These distinct mechanisms were validated through an integrative study, pointing on possible contribution of nitric oxide as a modulator of tobacco smoke dependence, in agreement with results of the literature study implying this neuromediator in all forms of dependence. The mechanism sustaining predisposition, the initiation and the reasons for the evolution toward dependence and relapses are currently investigated. The works in these fields suggest that modifications of certain proteins propagate long term signals and that reactive oxygen and nitrogen species are behind the mechanisms of long term potentiation and depression. Our work shows that cotinine is not toxic [422,423], is a pure psychoactive drug [414], with a novel non nicotinic pharmacological profile [416,417,419,422,423], is transported into brain [415], and its transport in regulated through peripheral nicotinic acetylcholine receptors [412,421], shows the endogenous and exogenous forms of cotinine [424], the cotinine receptor mediation of anti stress activity [420] and its homology to human proteins implicated in inflammatory reactions [36,161], paracrine stimulation of cell growth [55], dopamine release and the production of lipid peroxydation by cotinine administration [418], reinforcement in flexible approaches, the participation of emotional states and anxiety to anxiolytic response of the administration and anxiogenic response of withdrawal. They permit to propose that nicotine acts directly and indirectly through its conversion to cotinine. The later acts principally through its receptors, in brain through p40, to modulate dopamine release with consequence on learning, reward, oxidative stress, anxiety and long term potentiation and depression responses. As a conclusion, our work has permitted to propose novel pharmacological targets, methods and concepts in attempt to unify biochemical, neurochemical, molecular and behavioral mechanisms of addiction, hoping that these knowledge will be used to understand differences in susceptibility and to develop novel approaches for prevention and treatment., Le tabagisme est reconnu comme une dépendance comparable aux autres dépendances : alcool, opiacées et autres psycho-stimulants. Les mécanismes responsables de l'initiation et du maintien de l'addiction sont également impliqués dans les déviations comportementales en général, comme les déviations nutritionnelles, les compulsions.... La nicotine de la feuille de tabac est très toxique, dès son absorption, elle atteint le cerveau et tout l'organisme, active ses récepteurs et produit des effets toxiques et des adaptations homéostatiques. L'importance de ses effets va dépendre de la dose, du mode d'administration, de la chronicité, de l'effet considéré, du génome considéré et des interactions avec son principal dérivé, la cotinine. La cotinine résulte de l'addition d'un atome d'oxygène en position α du noyau pyrrolidine. Les conséquences de cette métabolisation ont été évaluées, dans l'étude présente, en partant des structures chimiques de ces deux alcaloïdes jusqu'à l'isolement des mécanismes biochimiques, neurochimiques, moléculaires et comportementaux de leurs actions. Ces différents mécanismes ont été validés par une étude intégrative en pointant le monoxyde d'azote NO comme un médiateur de la dépendance tabagique, en accord avec les données de l'étude bibliographique qui impliquent ce même médiateur dans toutes les dépendances. Les mécanismes à la base des prédispositions, le début et les raisons de l'évolution vers un état dépendant et les raisons des rechutes font l'objet d'intenses investigations. Les travaux dans ce domaine suggèrent que certaines modifications des protéines transmettent un signal de longue durée et que les espèces réactives de l'oxygène et du nitrogène sont à la base des mécanismes de potentialisation et de dépression à long terme. Notre travail montre une absence de toxicité pour la cotinine [422,423], une activité psychostimulante pure [414], une pharmacologie nouvelle non nicotinique [416,417,419,422,423], un passage actif [415] dans le cerveau régulé par le système nicotinique périphérique [412,421], la forme endogène et exogène de la cotinine [424], la médiation d'activité anti stress du récepteur p40 de la cotinine [420] et son homologie avec les protéines humaines impliquées dans les réactions inflammatoires [36,161], stimulatrice paracrine de la croissance cellulaire [55], un rôle dans la libération de dopamine, la production d'un stress oxydant par l'administration de la cotinine [418], un renforcement dans le contexte des approches flexibles, la participation forte des états émotionnels et d'anxiété à l'action anxiolytique de l'administration et anxiogène du retrait de la cotinine. Ils permettent de proposer que la nicotine agit directement et indirectement par sa conversion en cotinine. Cette dernière agit par ses récepteurs, au niveau central par la p40, pour moduler les taux de dopamine avec des conséquences sur l'apprentissage, la récompense, le stress oxydatif, l'anxiété et les réponses potentialisées et déprimées à long terme. Comme conclusion, nos travaux permettent de proposer de nouvelles cibles pharmacologiques, méthodes et concepts permettant de comprendre à l'échelle biochimique, neurochimique, moléculaire et comportemental l'addiction tabagique. L'espoir est d'utiliser ces connaissances pour différencier les susceptibilités et développer de nouvelles approches préventives et thérapeutiques.

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