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International audience; Autism is one of the most common developmental disorders in the world. It is defined by inadequate interaction and com- munication. This disorder induces an altered perception. We started from the sources of stress and discomfort in order to create a comforting atmosphere that allows the autistic child to progress in his care center. We so followed a multidisciplinary approach between teams of architects, engineers and child psychiatrists. Our methodology was based on the latest technologies in cognitive science in the capture of the emotional state correlated with the behavioral model, called sensory profile. We aim to propose an architectural space adequate to the sensitive particularities of autistic children in order to guarantee their well-being and comfort.

International audience; Among the UAVs, quadrotors are now the most popular and studied drones. These drones are called upon to perform various tasks, particularly the transport of increasingly heavy instruments or parcels, while keeping a structure as light as possible. The arms will inevitably deform under these loads, altering the flying machine's dynamic behavior. Precise drone flight control systems require rigorous dynamic modeling, taking into account the effect of deformation. In this study, we propose and evaluate an original design of a flexible quadcopter that will optimize its maneuverability and controllability in tight and complex spaces, even when carrying relatively heavy loads. The principle is based on the Lagrange method. The introduction of deformation is done through additional degrees of freedom. The effects of elastic deformation, rigid body motion, and coupling between them are all included in the final model. Based on the dynamic model built, we propose a new non-linear controller, which takes into account the arms deformation. The proposed controller adapts well to disturbances due to the effect of deformation, improving the trajectory tracking capability of the system. We will demonstrate the exponential stability of a compensated tracking error.

International audience; This study assessed the potential use of a mixture of lime and water hyacinth ash (WHA) as binders in fabrication of cylindrical compressed earth blocks (CEBs) with good acoustic absorption properties for building and construction. Different concentrations of the binders and compaction pressures were employed so as to vary the acoustical properties of the fabricated blocks. The geometric and transport parameters of their porous microstructure were recovered through probing using acoustic waves. A low-frequency acoustic wave guide was built for this purpose. It was found out that the transmission coefficient decreased with the compaction pressure, and with addition of lime, while WHA increased the transmission coefficient. The non-acoustical parameters recovered using the equivalent fluid model (JCAL) showed that the variation of the geometry of the microstructure of the blocks is what influences the acoustic transmission coefficient. Thus, the properties of the CEBs can be steered using binder concentration and compaction pressure in a controlled manner.

International audience; Our study is an attempt to contextualize a formerreality, which has been forgotten, that of the Jewish quarter of the Medina of Tunis, and houses of wealthy citizens who were there. Going beyond a simple restoring of a "zeitgeist", we questioned the ambiantal potential of the place, as well as the "inhabitants sensitivities" (Morel-Brochet, 2012, p. 86), through three successive periods : 1. eighteenth and nineteenth centuries, 2. French Protectorate, 3. from independence until our days. In order to achieve this, we will have recourse to autobiographical stories of Tunisian-Jewish authors, direct observations supported by interviews with some current residents.

International audience; Our study is an attempt to contextualize a formerreality, which has been forgotten, that of the Jewish quarter of the Medina of Tunis, and houses of wealthy citizens who were there. Going beyond a simple restoring of a "zeitgeist", we questioned the ambiantal potential of the place, as well as the "inhabitants sensitivities" (Morel-Brochet, 2012, p. 86), through three successive periods : 1. eighteenth and nineteenth centuries, 2. French Protectorate, 3. from independence until our days. In order to achieve this, we will have recourse to autobiographical stories of Tunisian-Jewish authors, direct observations supported by interviews with some current residents.

Part of topic : Ambiantal experiences and experiments; International audience; The research presents the results of an exploratory study on the user’s experience in an open plan office in Tunisia. Ambiantal approach was adopted as a method of studying this standard environment work. With palliative actions, users of open plan office try to have a suitable environment.

Part of topic : Ambiantal experiences and experiments; International audience; Autistic children and presbycusis elderly are examples of ‘specific’ space users which altered perception of sonic ambiances in particular affects their relationship to the urban and architectural space. Our research is on crossroads of several disciplines. It focuses on analysis of stress levels for those particular populations in some daily situations in urban and architectural spaces, using Electro-Dermal Activity (EDA) tracking that evaluates the arousal via skin conductance measurements. The understanding of discrete situations of anxiety should be useful to find a balance between standard and quality in space design, taking sonic ambiances into account.

Part of topic : Ambiance as heritage of the future; International audience; Our study is an attempt to contextualise a former reality, which has been forgotten, that of the Jewish quarter of the Medina of Tunis, and houses of wealthy citizens who were there. Going beyond a simple restoring of a ‘zeitgeist’, we questioned the ambiantal potential of the place, as well as the ‘inhabitants sensitivities’ (Morel-Brochet, 2012, p. 86), through three successive periods: 1. eighteenth and nineteenth centuries, 2. French Protectorate, 3. from independence until our days. In order to achieve this, we will have recourse to autobiographical stories of Tunisian-Jewish authors, direct observations supported by interviews with some current residents.

Part of topic : Ambiance as heritage of the future; International audience; The proposed research questions the sensory imaginary, especially sound, of travellers who visited the Souks of the Medina in the 19thcentury. The restitution of this ambiantal memory is used to participate in the reconsideration of the urban and architectural heritage of this highly historic space, the Souks, by sonic ambiances. Our ambiantal approach is based on quantitative and qualitative (notion of sound effect) content analysis of the 19thcentury texts.

Part of topic : Ambiantal experiences and experiments; International audience; We propose to verify if the development of mobile applications can help students in architecture in their design: if it allows them to take the specificities of ambiantal approach in their daily practice. We assume that the access to applications is a catalyst for designers, allowing them to focus on their conceptual approaches on the perception of users of the projected spaces. To test these hypotheses, we first took stock of mobile applications available. We subsequently conducted an experiment with a corpus of students to test mobile applications and ‘traditional’ tools to achieve the measurements and evaluations of light, heat, sound, humidity, ventilation and assessment of sensitive user’s experience.

Part of topic : Ambiance, atmosphere, climate: theory, politics and criticism; International audience; This text aims, through the study of the first chapter of Ecumes – Sphères III (Sloterdijk, 2005), to show links between atmosphere theory and islandmorphic and islandgenic view of world explicitness. We question this explicitness to know if it can take place in a kind of genetic epistemology of a living together and being human space and if it can let emerge a new comprehension of living and sharing spaces of tomorrow regarding to the anthropogenetic islands specificities. A special focus will concern the ‘chirotope’ – first dimension of anthropogenetic island – for its big importance for ‘island-arity’.

International audience; Le processus de conception architecturale semble être complexe et nécessiterait le recours à un grand nombre de matériaux. Saisir, retranscrire et créer les ambiances architecturales compterait parmi les phases importantes de ce processus et requerrait des situations de mobilité. L'objectif de cet article est de tenter d'identifier les différents modes de la mobilité utilisés au sein du processus de conception architecturale.

International audience; The proposed study concerns the local cultural history related to manufacturing, management and control of lighting situations in the big mansions of the medina of Tunis between 1704 and 1815. The methodology adopted will be based on what we might call an 'ethnoscenology of the sensitive' regarding the reconstruction of events and actions, especially the adaptive procedures deployed by the inhabitants, to dose, adjust and improve the brightness of internal spaces. Knowing that the usual hypotheses associated with these practices are difficult to verify today, we are going to use written records of that time.

The conducted research is an attempt to rebuild ambient lighting in the huge dwellings of the Bey ruling time's dignitaries, in the 18th and early 19th century (1704-1815), located in the medina of Tunis. The research aims at understanding the respective roles of the "architect" and the employees in this "highlighting" of traditional domestic space of Tunis. Two main points articulated our thinking: the first concerns the profile of the inhabitants and of the head of the guild of master masons, who is responsible for the work design and execution; the second point concerns the characterization of the dwelling's ambient lighting spaces. The approach method is interactional. It allows to combine the socio-historical part with the experimental one. This method applies to geometric modeling, numerical simulation as well as light measurements taking, performed in one of our corpus dwellings, namely dãr Ben Abdallah (Bãb el-Jazeera). The types of piercing and solar protection items that were added, as well as their orientation and location in the dwelling, were also analyzed. Moreover, using lighting SOLENE software (CERMA, UMR, CNRS 1563), we developed Light Maps to describe three life stages considered representative of family life of the time. These are: 1. A reproduction of the owner's relaxation moment: the Minister Slimãne Kéhia in his private observatory (kushk), 2. A meeting between his wife, Princess Aziza and her guests in the " T " shape Room of the guest house, 3. A working day, particularly a laborious one, experienced by young black servants on the occasion of the family's annual supplying with couscous. Each of these scenes took place at a particular time of the year and within a specific area of the house. The obtained results allowed us to understand the relationship existing between the users tastes and desires on the one hand, the architect's constructive practices, and know-how on the other, and the lighting quality of the inhabited spaces. So why not speak of a " culture of light " that emerges through people's actions and their way of managing, adjusting, and controlling lighting devices with respect to their mode of life, tastes and aspirations?, La recherche que nous menons est un essai de reconstitution des ambiances lumineuses dans les grandes demeures des dignitaires du pouvoir beylical du XVIIIe et du début du XIXe siècle (1704-1815), situées dans la médina de Tunis. Notre objectif est de comprendre les rôles respectifs de l' " architecte " et des usagers dans cette " mise en lumière " de l'espace domestique traditionnel tunisois. Deux points essentiels ont articulé notre réflexion. Le premier point concerne le profil des habitants et du chef de la corporation des maîtres-maçons, chargé de la conception et de l'exécution des travaux, le deuxième point porte sur la caractérisation des ambiances lumineuses des espaces de la demeure. Notre méthode d'approche est de type interactionnelle. Elle nous permet de combiner le volet lié à l'histoire-sociale avec le volet expérimental. Cette méthode s'applique à la modélisation géométrique, à la simulation numérique ainsi qu'aux prises de mesures d'éclairement, effectuées dans une des demeures de notre corpus, à savoir dãr Ben Abdallah (quartier Bãb el-Jazîra). Les types de percement et d'éléments de protection solaire qui leur ont été ajoutés, ainsi que leur orientation et leur emplacement dans la demeure, ont été de même analysés. Par ailleurs, à l'aide du logiciel d'éclairement SOLENE (CERMA, UMR, CNRS 1563), nous avons dressé des cartographies d'éclairement, pour décrire trois scènes de vie que nous avons considéré comme étant représentatives de la vie familiale de l'époque. Il s'agit : 1. D'une restitution d'un moment de détente du propriétaire, le ministre Slimãne Kéhia dans son observatoire privé (kushk), 2. D'une rencontre entre son épouse, la princesse Aziza avec ses invitées, dans la salle en " T " de la maison des hôtes, 3. D'une journée de travail, particulièrement laborieuse, vécue par les jeunes servantes noires, à l'occasion de l'approvisionnement annuel de la famille en couscous. Chacune de ces trois scènes se déroulaient à des moments particuliers de l'année et dans un espace spécifique de la demeure. Les résultats obtenus nous ont permis de saisir la relation existante entre les goûts et les désirs des usagers d'une part, les pratiques constructives et le savoir-faire de l' " architecte " d'autre part, avec la qualité lumineuse des espaces habitables. Pourquoi donc ne pas parler d'une " culture de la lumière ", qui se dessine à travers les faits et gestes des habitants et dans leur façon de gérer, d'ajuster et de contrôler les dispositifs d'éclairement par rapport à leur mode de vie, à leurs goûts et aspirations ?

The conducted research is an attempt to rebuild ambient lighting in the huge dwellings of the Bey ruling time's dignitaries, in the 18th and early 19th century (1704-1815), located in the medina of Tunis. The research aims at understanding the respective roles of the "architect" and the employees in this "highlighting" of traditional domestic space of Tunis. Two main points articulated our thinking: the first concerns the profile of the inhabitants and of the head of the guild of master masons, who is responsible for the work design and execution; the second point concerns the characterization of the dwelling's ambient lighting spaces. The approach method is interactional. It allows to combine the socio-historical part with the experimental one. This method applies to geometric modeling, numerical simulation as well as light measurements taking, performed in one of our corpus dwellings, namely dãr Ben Abdallah (Bãb el-Jazeera). The types of piercing and solar protection items that were added, as well as their orientation and location in the dwelling, were also analyzed. Moreover, using lighting SOLENE software (CERMA, UMR, CNRS 1563), we developed Light Maps to describe three life stages considered representative of family life of the time. These are: 1. A reproduction of the owner's relaxation moment: the Minister Slimãne Kéhia in his private observatory (kushk), 2. A meeting between his wife, Princess Aziza and her guests in the " T " shape Room of the guest house, 3. A working day, particularly a laborious one, experienced by young black servants on the occasion of the family's annual supplying with couscous. Each of these scenes took place at a particular time of the year and within a specific area of the house. The obtained results allowed us to understand the relationship existing between the users tastes and desires on the one hand, the architect's constructive practices, and know-how on the other, and the lighting quality of the inhabited spaces. So why not speak of a " culture of light " that emerges through people's actions and their way of managing, adjusting, and controlling lighting devices with respect to their mode of life, tastes and aspirations?; La recherche que nous menons est un essai de reconstitution des ambiances lumineuses dans les grandes demeures des dignitaires du pouvoir beylical du XVIIIe et du début du XIXe siècle (1704-1815), situées dans la médina de Tunis. Notre objectif est de comprendre les rôles respectifs de l' " architecte " et des usagers dans cette " mise en lumière " de l'espace domestique traditionnel tunisois. Deux points essentiels ont articulé notre réflexion. Le premier point concerne le profil des habitants et du chef de la corporation des maîtres-maçons, chargé de la conception et de l'exécution des travaux, le deuxième point porte sur la caractérisation des ambiances lumineuses des espaces de la demeure. Notre méthode d'approche est de type interactionnelle. Elle nous permet de combiner le volet lié à l'histoire-sociale avec le volet expérimental. Cette méthode s'applique à la modélisation géométrique, à la simulation numérique ainsi qu'aux prises de mesures d'éclairement, effectuées dans une des demeures de notre corpus, à savoir dãr Ben Abdallah (quartier Bãb el-Jazîra). Les types de percement et d'éléments de protection solaire qui leur ont été ajoutés, ainsi que leur orientation et leur emplacement dans la demeure, ont été de même analysés. Par ailleurs, à l'aide du logiciel d'éclairement SOLENE (CERMA, UMR, CNRS 1563), nous avons dressé des cartographies d'éclairement, pour décrire trois scènes de vie que nous avons considéré comme étant représentatives de la vie familiale de l'époque. Il s'agit : 1. D'une restitution d'un moment de détente du propriétaire, le ministre Slimãne Kéhia dans son observatoire privé (kushk), 2. D'une rencontre entre son épouse, la princesse Aziza avec ses invitées, dans la salle en " T " de la maison des hôtes, 3. D'une journée de travail, particulièrement laborieuse, vécue par les jeunes servantes noires, à l'occasion de l'approvisionnement annuel de la famille en couscous. Chacune de ces trois scènes se déroulaient à des moments particuliers de l'année et dans un espace spécifique de la demeure. Les résultats obtenus nous ont permis de saisir la relation existante entre les goûts et les désirs des usagers d'une part, les pratiques constructives et le savoir-faire de l' " architecte " d'autre part, avec la qualité lumineuse des espaces habitables. Pourquoi donc ne pas parler d'une " culture de la lumière ", qui se dessine à travers les faits et gestes des habitants et dans leur façon de gérer, d'ajuster et de contrôler les dispositifs d'éclairement par rapport à leur mode de vie, à leurs goûts et aspirations ?

International audience; This paper addresses the jobshop and the flowshop scheduling problems with minimum and maximum time lags. To solve this kind of problems, we propose adaptations of Climbing Discrepancy Search (CDS). We study various parameter settings. Computational experiments are provided to evaluate the propositions.

Mise à disposition du document numérique avec l'aimable autorisation de l'éditeur; International audience; Ce travail concerne la caractérisation de l'ambiance dans le lycée de Carthage, une réalisation majeure de l'architecte Jacques Marmey en Tunisie. Les investigations révèlent des modalités conceptuelles de l'ambiance plus intuitives que systématiques. On est amené à penser que Jacques Marmey s'appuie essentiellement sur sa propre expérience sensible qu'il cherche à transposer en proposant, par ajustement progressif, un environnement sensible qui prend forme à travers un répertoire de dispositions construites ouvertes. Cette ouverture, dont le potentiel à faciliter l'accessibilité réelle et perceptuelle efface les éventuels effets gênants de turbulence, d'éblouissement ou de surchauffe, s'avère être à l'origine de l'expérience esthétique usagère.

Mise à disposition du document numérique avec l'aimable autorisation de l'éditeur; International audience; L'objet de notre contribution vise à répondre à un des questionnements posés par le programme scientifique du colloque, à savoir : " Comment fait-on une ambiance dans le projet d'architecture et d'urbanisme ? ". L'étude présentée est historico-sociale. Elle consiste à comprendre par quels moyens l' " architecte " tunisien du XVIIIes traduisait ses intentions de " mise en lumière " de l'espace domestique citadin. A cette fin, nous nous intéresserons à tout ce qui relève de la " fabrication " d'ambiances lumineuses dans la grande demeure tunisoise de la période husseinite : types d'ouverture, types de dispositions spatiales, modes d'agencement des espaces. Pouvons nous affirmer que cet " architecte " se préoccupait de la " mise en ambiances lumineuses " de la demeure d'une manière consciente et réfléchie ?

Bat species richness and activity in Dghoumes National Park (Southwest Tunisia): a preliminarysurvey. Bat fauna in eight of the main habitat types of Dghoumes National Park wasinventoried using mist–netting, acoustic detection and roost search. Bats were active at nightand recorded near water bodies and street lamps. We recorded the echolocation calls ofsix bat species: Eptesicus isabellinus, Pipistrellus kuhlii, Vansonia rueppellii, Asellia tridens,Tadarida teniotis and Rhinopoma cystops. Two bat colonies containing 111 individuals ofR. cystops were found roosting in Jebel Morra cave and 54 individuals of A. tridens werefound roosting in the ceiling of the Ecomuseum. Due to potential disturbance by visitors tothe museum, we suggest strengthening management practices to ensure the usage of thisroosting site in order to promote the conservation of A. tridens.; Bat species richness and activity in Dghoumes National Park (Southwest Tunisia): a preliminary survey. Bat fauna in eight of the main habitat types of Dghoumes National Park was inventoried using mist-netting, acoustic detection and roost search. Bats were active at night and recorded near water bodies and street lamps. We recorded the echolocation calls of six bat species: Eptesicus isabellinus, Pipistrellus kuhlii, Vansonia rueppellii, Asellia tridens, Tadarida teniotis and Rhinopoma cystops. Two bat colonies containing 111 individuals of R. cystops were found roosting in Jebel Morra cave and 54 individuals of A. tridens were found roosting in the ceiling of the Ecomuseum. Due to potential disturbance by visitors to the museum, we suggest strengthening management practices to ensure the usage of this roosting site in order to promote the conservation of A. tridens. Data published through GBIF (Doi: 10.15470/0u03uz) Resumen Riqueza de especies y actividad de murciélagos en el Parque Nacional de Dghoumes (suroeste de Túnez): un estudio preliminar. Se estudió la fauna de murciélagos en ocho de los principales tipos de hábitats del Parque Nacional de Dghoumes utilizando redes de niebla, detección acústica y búsqueda de refugios. Los murciélagos estuvieron activos du-rante la noche y se localizaron en la proximidad de masas de agua y farolas de alumbrado público. Se registraron seis especies de murciélagos: Eptesicus isabellinus, Pipistrellus kuhlii, Vansonia rueppellii, Asellia tridens, Tadarida teniotis y Rhinopoma cystops. Se localizaron dos colonias, una de R. cystops con 111 individuos colgados en la cueva de Jebel Morra y otra con 54 individuos de A. tridens en el techo del Ecomuseo. Ante la posible pertur-bación causada por los visitantes del museo, sugerimos reforzar las medidas de gestión del público para garantizar el uso de este lugar de descanso de los murciélagos, lo que impactaría positivamente en la conservación de A. tridens. Datos publicados en GBIF (Doi: 10.15470/0u03uz)

International audience; Introduction to the thematic issue on government‐provided services

In this work, a new voltammetric biosensor, based on the encapsulation of laccase from Trametes versicolor in an electrodeposited nanocomposite film, was developed for the detection of catechol. The nanocomposite was composed of chitosan (CS) modified with trymiristine (Tr), both of natural origin, to enhance its conductivity. FTIR and SEM studies were performed to characterize the modified chitosan film and the encapsulation of the enzyme. The analytical performance of the elaborated biosensor was determined through voltammetry detection of the produced quinone. Catechol was detected in a linear range between 10–20 and 10–15 M and a sensitivity of 0.4667 mA/p [catechol] was found. The repeatability of this biosensor is good as its RSD is equal to 1.35% and it shows stability for four weeks. To test the functionality of the developed biosensor, the total phenolic content of three samples of natural oils was determined and compared to a colorimetric test.

In addition to a variety of viral-glycoprotein receptors (e.g., heparan sulfate, Niemann-Pick C1, etc.), dendritic cell-specific intercellular adhesion molecule-3-grabbing nonintegrin (DC-SIGN), from the C-type lectin receptor family, plays one of the most important pathogenic functions for a wide range of viruses (e.g., Ebola, human cytomegalovirus (HCMV), HIV-1, severe acute respiratory syndrome coronavirus 2, etc.) that invade host cells before replication; thus, its inhibition represents a relevant extracellular antiviral therapy. We report two novel p-tBu-calixarene glycoclusters 1 and 2, bearing tetrahydroxamic acid groups, which exhibit micromolar inhibition of soluble DC-SIGN binding and provide nanomolar IC50 inhibition of both DC-SIGN-dependent Jurkat cis-cell infection by viral particle pseudotyped with Ebola virus glycoprotein and the HCMV-gB-recombinant glycoprotein interaction with monocyte-derived dendritic cells expressing DC-SIGN. A unique cooperative involvement of sugar, linker, and calixarene core is likely behind the strong avidity of DC-SIGN for these low-valent systems. We claim herein new promising candidates for the rational development of a large spectrum of antiviral therapeutics.

International audience

A sample of MgO was successfully synthesized using thermal decomposition of hydromagnesite and compared to commercial material. The characterization of materials using XRD, SEM, BET and BJH methods showed that the thermal decomposition way led to rectangular mesoporous microsheets with high specific surface area of 100 m2 g−1. This porous magnesium oxide has been shown to be a potential candidate for CO2 capture at low temperatures range (30 and 50 °C), low pressures of CO2 ( $$ P_{{{\text{CO}}_{2} }} = 600\;{\text{mbar}} $$ ) and in the presence of water vapor ( $$ P_{{{\text{H}}_{2} {\text{O}}}} = 15\;{\text{mbar}} $$ ). In these conditions, our results show that 11% of MgO was converted to hydrated magnesium carbonate MgCO3·3H2O after 8 h of carbonation in a thermobalance and reached 54% after 24 h of carbonation using tube furnace. After carbonation, hydration reaction pore size and surface area have noticeably changed.

International audience; The Bou Jaber ore deposit is one of the numerous diapir-related Pb–Zn–F–Ba deposits of the Dome Zone in Northern Tunisia. Its location is controlled by the regional NE-SW Tajerouine Fault.Ore minerals are hosted in the Late Aptian limestones (Serdj Formation) as open space filling and stratabound replacement bodies. According to Bouhlel et al. (2016), the poly-phase mineralization resulted from the successive activity of three mineral systems, a Pb–Zn, then a barite, and eventually a fluorite deposition system. The latter, from the Late Miocene, is demonstrated in the present study.The fluorite system is characterized by the involvement of oil in the hydrothermal fluids. This oil was produced in the local environment of the deposit from the thermal maturation of the Albian Fahdene black shale source-rock at temperature range of~140 °C–~100 °C. Two brines were involved in the fluorite hydrothermal system. The first one (L1) is a Ca-rich brine (≥20 wt % bulk salinity), with Na/Ca ≤ 0.18, which is thought to have long resided in the basement, before its transfer into the Jurassic reservoir (Upper Nara Formation) and its eventual mobilization at the time of ore deposition. The second brine (L2), less saline (≤14 wt % bulk salinity) is more sodic, with Na/Ca up to 0.53, and represents unmodified brine originated from the nearby Triassic salt. The L1 brine was F-bearing, whereas the L2 brine was associated with oil. Fluorite deposition occurred at the estimated shallow depth of 1.7 km from cooling of the L1 brine due to the first isobaric cooling from ~160 °C to 135 °C under sub-lithostatic conditions (36 MPa). This stage is followed by mixing with the newly incoming L2 brines (transporting oil) along a sub-isochoric decompression path (down to the hydrostatic pressure at 17 MPa) and continuously cooling from 135 °C to 125 °C. The cooling and mixing caused fluorite deposition after which a transient heat advection episode (up to 145 °C) caused late calcite deposition prior to the end of hydrothermal circulation.

congrès virtuel; International audience

International audience; In this paper, we present the stabilization of an unconventional unmanned airship above a loading and unloading area. The study concerns a quad-rotor flying wing airship. This airship is devoted to freight transport. However, during the loading and unloading phases, the airship is very sensitive to squalls. In this context, we present in this paper the dynamic model of the airship, and we propose a strategy for controlling it under the effects of a gust of wind. A feedforward/feedback control law is proposed to stabilize the airship when hovering. As part of the control allocation, the non-linear equations between the control vectors and the response of the airship actuators are highlighted and solved analytically through energy optimization constraints. A comparison with classical numerical algorithms was performed and demonstrated the power and interest of our analytic algorithm.

International audience; We report hot-wire measurements performed in two very different, co-and counter-rotating flows, in normal and superfluid helium at 1.6 K, 2 K, and 2.3 K. As recently reported, the power spectrum of the hot-wire signal in superfluid flows exhibits a significant bump at high frequency [Diribarne et al., Phys. Rev. B 103, 144509 (2021)]. We confirm that the bump frequency does not depend significantly on the temperature and further extend the previous analysis of the velocity dependence of the bump, over more than one decade of velocity. The main result is that the bump frequency depends on the turbulence intensity of the flow, and that using the turbulent Reynolds number rather than the velocity as a control parameter collapses results from both co-and counter-rotating flows. The vortex shedding model previously proposed, in its current form, does not account for this observation. This suggests that the physical origin of the bump is related to the small scale turbulence properties of the flow. We finally propose some qualitative physical mechanism by which the smallest structures of the flow, at intervortex distance, could affect the heat flux of the hot-wire.

International audience; We consider a general equilibrium model with vertical preferences, where workers and consumers are differentiated respectively by their sensitivity to effort and their intensity of preference for quality. We consider a public monopoly, i.e. which is owned equally by all individuals. The question is under which conditions the firm will be privatized and at which rate/price. The decisions are taken through majority vote in a plurality system. When the firm is controlled by the State, the price is determined through a vote among all the population. Otherwise, the price is the one which maximizes the profit. We prove that, when the maximum disutility of working in the firm is higher than the maximum utility of consuming its output, privatization may emerge as a possible choice of the majority, even if no hypothesis is made on the efficiency of a private management relative to a public one.

International audience; For possible applications as trapped field (TF) magnets, it is essential to fabricate large, polycrystalline bulk samples from the FeSe compound, the simplest high-Tc superconductor (HTSc) possible. FeSe is relatively cheap to prepare, and does not contain any rare-earth material. The grain boundaries in this compound are not acting as weak links as it is the case for the YBCO compound. Although the transition temperature, Tc, is just below 10 K, the upper critical fields are comparable with other HTSc. Preparing the FeSe samples using solid-state sintering yields samples exhibiting strong magnetic hysteresis loops (MHLs), and the superconducting contribution is only visible after subtracting MHLs from above Tc. Due to the complicated phase diagram [1], the samples are a mixture of several phases, α-FeSe, β-FeSe, δ-FeSe (Fe7Se8) and metallic α-Fe [2]. The amount of the latter two phases depends directly on the Se loss during the sintering process. The δ-FeSe is antiferromagnetic, and α-Fe is ferromagnetic [3]. In the present contribution, we show MHLs of a variety of samples measured up to ±7 T and determine the magnetic characteristics, together with the amount of superconductivity determined from M(T) measurements. We performed a thorough analysis of the microstructures using polarization microscopy, Kerr effect, MFM, SEM, EBSD and TEM in order to establish a relation between microstructure and sample properties. To prepare good superconducting samples, the presence of the (anti)ferromagnetic phases must be reduced by carefully adjusting the Se content using Ti foils as getter materials. Measuring magnetoresistance of these samples [4] implies that the samples are always cooled in the own local field, and thus, the analysis of the resistance data calculating the fluctuation-induced conductivity above Tc [5] is strongly affected by this local magnetic field. We demonstrate the importance of preparing phase-pure FeSe samples, which are essential for the various applications envisaged. This work is part of the SUPERFOAM international project funded by ANR and DFG under the references ANR-17-CE05-0030 and DFG-ANR Ko2323-10, respectively. References [1] H. Okamoto, J. Phase Equilibria 12, 383 (1991). [2] P. Diko et al., Physica C 476, 29 (2012). [3] A. J. Williams, T. M. McQueen, R. J. Cava, Solid State Commun.149, 1507 (2009). [4] T- Karwoth et al., J. Phys. Conf. Ser. 1054, 012018 (2018). [5] A. Almessiere et al., Mat. Chem. Phys. 243, 122665 (2020).

International audience; Zeolites were synthesized from natural Tunisian clay by hydrothermal treatment under high pressure (100 MPa H 2 O pressure) at different gradients of temperature in high pressure autoclaves. The natural clay was first heated at 650 � C (HC-heated clay) and then transformed to an amorphous phase at 650 � C by adding different amount of NaOH. By increasing temperature and NaOH content, low-density frameworks zeolites like faujasite are transformed into more stable zeolites having higher density frameworks like cancrinite due to dissolution and recrystallisation steps. Cancrinite (Na 8 (H 2 0) 2 CO 3 [Al 6 Si 6 O 24 ]) (IZA-code: CAN) was successfully synthesized with a good purity. The synthesized CAN was characterized by X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM). The removal performance of heavy metal ions (Cd 2þ , Pb 2þ) from solution by pure CAN and clays has been studied. The kinetics of adsorption of Cd 2þ and Pb 2þ are very fast: equilibrium is reached within 2 min at 298 K. The capacity of adsorption of CAN is higher for Pb 2þ (192 mg g À 1) than for Cd 2þ (68 mg g À 1). Adsorption equilibrium of Cd 2þ and Pb 2þ on CAN were well represented by Langmuir equation although the thermodynamic study reveals a more complex mechanism: thermodynamic parameters, such as equilibrium constant, free energy, entropy and enthalpy for adsorption were obtained from the experimental data, including adsorption microcalorimetry.

We consider a general equilibrium model with vertical preferences, where workers and consumers are differentiated respectively by their sensitivity to effort and their intensity of preference for quality. We consider a public monopoly, i.e. which is owned equally by all individuals. The question is under which conditions the firm will be privatized and at which rate/price. The decisions are taken through majority vote in a plurality system. When the firm is controlled by the State, the price is determined through a vote among all the population. Otherwise, the price is the one which maximizes the profit. We prove that, under some conditions on the dispersion of consumers relative to workers, privatization may emerge as a possible choice of the majority, even if no hypothesis is made on the efficiency of a private management relative to a public one.

International audience; In this contribution, a new concept of voltammetric catechol biosensor, based on the encapsulation of laccase (LAC) in a chitosan+lambda-carrageenan (CHIT+CAR) polyelectrolyte complex (PEC) employing a simple coacervation process is presented. Chitosan (CHIT) was prepared from alpha-chitin extracted from shrimp shells and lambda-carrageenan (CAR) was extracted from red algae, both polysaccharides and PEC being characterized using FTIR spectrometry and electrochemistry. Cyclic voltammetry was utilized to determine the analytical features of the laccase (LAC) biosensor for catechol detection. The linear range was from 10(-20) M to 10(-14) M with a sensitivity of 1.55 mA/p[catechol] and a limit of detection of 3x10(-21) M.The laccase biosensor exhibits good repeatability (RSD 2.38 %) and stability (four weeks). The developed biosensor was tested by applying it to the evaluation of the total polyphenolic content in natural oil samples.

In this paper, we analyse the effect of an environmental policy that targets to enhance ecosystems integrity as well as air quality in the wholesale electricity market. We developed a dynamic Cournot game between a hydro and a thermal risk adverse electricity producers under demand uncertainty. We demonstrate that while improving air quality necessarily raises the market price, enhancing ecosystems integrity can, under water abundance hypothesis, reduce it. Moreover, in order to establish a statement about the environmental policy efficiency, we examine interactions between both environmental measures and their potential side effects. We show that prioritizing natural flow regime minimises necessarily the taxation efficiency on lowering air pollution and emphasizes the price rise due to the taxation. Nevertheless, the effect of the taxation policy on the efficiency of the ecosystems integrity policy depends on the hydro producer's ability to substitute thermal units. In order to establish a precise environmental statement, the regulation authority needs to compare, using appropriate criteria , the importance of an avoided unit of surrounding ecosystem alteration to an avoided unit of air polluting production, in the whole ecosystem functioning.

Red luminescent and superparamagnetic &beta, NaY0.8Eu0.2F4@&gamma, Fe2O3 nanoparticles, made of a 70 nm-sized &beta, NaY0.8Eu0.2F4 single crystal core decorated by a 10 nm-thick polycrystalline and discontinuous &gamma, Fe2O3 shell, have been synthesized by the polyol process. Functionalized with citrate ligands they show a good colloidal stability in water making them valuable for dual magnetic resonance and optical imaging or image-guided therapy. They exhibit a relatively high transverse relaxivity r2 = 42.3 mM&minus, 1&middot, s&minus, 1 in water at 37 &deg, C, for an applied static magnetic field of 1.41 T, close to the field of 1.5 T applied in clinics, as they exhibit a red emission by two-photon excited fluorescence microscopy. Finally, when brought into contact with healthy human foreskin fibroblast cells (BJH), for doses as high as 50 &micro, g&middot, mL&minus, 1 and incubation time as long as 72 h, they do not show evidence of any accurate cytotoxicity, highlighting their biomedical applicative potential.

International audience; This note extends the results already obtained by Khaloul et al. (2017) on the majority vote between monopoly and duopoly by a heterogeneous population composed of individuals who are potentially consumers, workers, and shareholders to the general case where firms are owned by a given proportion of the population. Results show that duopoly is preferred when non-shareholders constitute a majority of the population. Otherwise, the majority vote depends on the relative dispersion of the individuals with respect to their intensity of preference for quality and their sensitivity to effort.

Fabrication, characterization and application of ceramic membrane developed from Tunisian natural kaolin clay for textile wastewater treatment are presented in this study. The morphology and properties of the resulting membrane sintered at 1000°C for 3 h were then determined by Scanning Electron Microscopy (SEM), mechanical and chemical resistance and water permeability. Separation performance of the membrane was evaluated during the treatment of textile wastewater. SEM images reveal the homogeneous surface of the membrane. The membrane displayed good chemical and mechanical resistances as well. Its permeability was of 21.2 L.h -1.m-2.bar-1, indicating that separation performance could occur in the domain of Ultrafiltration (UF). Performances of the membrane during the treatment of raw and biologically pretreated textile effluents are promising in terms of the removal of colour (99% for the raw effluent and 100% for the biologically pretreated effluent), chemical oxygen demand (COD) (80% for the raw effluent and 93% for the biologically pretreated effluent) and turbidity (98% for the raw effluent and 100% for the biologically pretreated effluent).

A voltammetric sensor for bisphenol A (BPA) detection was developed. It was based on a gold electrode modified by an electrodeposited molecularly imprinted chitosan (CS) film. Fourier Transformed Infrared spectroscopy, scanning electron microscopy and electrochemistry were used to characterize and compare the surface of the molecularly imprinted polymer (MIP) and non-molecularly imprinted polymer (NIP) films. The analytical performance of this biosensor was then established using square wave voltammetry (SWV) of the ferro/ferricyanide redox probe, in the range of −300 and 600 mV. The oxidation peak current was proportional to the logarithm of BPA concentration in the range between 10−3 M to 10−21 M with a limit of detection of 0.67 × 10−21 M. The elaborated sensor showed good repeatability (RSD 2.08%), reusability and recognition of BPA in the presence of similar structural moieties. The proposed sensors were successfully employed to determine BPA in real plastic bottles for drinking water.

We consider a general equilibrium model with vertical preferences for one good and two identical countries each having initially one firm. Citizens in each country are asked to vote either for openness or for autarky. Openness means that a foreign firm can sell and produce its product in the domestic country and that the domestic firm can sell and produce its product in the foreign country. The decision to open frontiers is effective only when it is bilateral. Citizens in each country are potentially consumers, workers and shareholders in the domestic firm. They differ with respect to their intensity of preference for quality and their sensitivity to effort. The regime which will prevail between countries corresponds to the majority vote in the low quality country, as we prove that citizens in the high quality country always vote for openness. The outcome thus depends in a complex way on the degree of concentration of the ownership structure in the low quality country and the relative dispersion of the citizens with respect to their intensity of preference for quality and their sensitivity to effort.

International audience; Katabatic winds are very frequent but poorly understood or simulated over steep slopes. This study focuses on a katabatic jet above a steep alpine slope. We assess the buoyancy terms in both the turbulence kinetic energy (TKE) and the Reynolds shear stressbudgetequations.We specifically focus on the contribution of the slope-normal and along-slope turbulent sensible heat fluxes to these terms. Four levels of measurementsbelowandabovethemaximumwin - speed height enable analysis of the buoyancy effect along the vertical profile as follow: (i) buoyancy tends to destroy TKE, as expected in stable conditions, and the turbulent moment m flux in the inner-layer region of the jet below the maximum wind-speed height z j ; (ii) results also suggest buoyancy contributes to the production of TKE in the outer-layer shear region of the jet (well above z j ) while consumption of the turbulent momentum flux is observed in the same region; (iii) In the region around the maximum wind speed where mechanical shear production is marginal, buoyancy tends to destroy TKE and our results suggest it tends to increase the momentum flux. The present study also provides an analytical condition for the limit between production and consumption of the turbulent momentum flux due to buoyancy as a function of the slope angle, similar to the condition already proposed for TKE. We reintroduce the stress Richardson number, which is the equivalent of the flux Richardson number for the Reynolds shear-stress budget. We point out that the flux Richardson number and the stress Richardson number are complementary stability parameters for characterizing the katabatic flow apart from the region around the maximum wind-speed height.

Dicalcium silicate finds applications in different fields (cement, bio-ceramics, refractories). In the case of Portland cement, its interest is its lower sintering temperature compared to tricalcium silicate and therefore an interesting compound for low CO2 cements. Dicalcium silicate goes through different polymorphic forms, namely α, α'H, α'L, β and γ, as the temperature decreases. In theory, only the γ-phase is stable at room temperature. In a polycrystalline material, the different polymorphs can co-exist depending on several factors (sintering conditions, presence of impurities, grain size) and the interpretations given in the literature are sometimes contradictory. For cement applications, only the α, α' or β polymorphs react with water to give hydrates while γ does not. Therefore, this paper focuses specifically on the effect of grain size on the β to γ transformation. We also propose that the transformation is semi-reconstructive and not martensitic as suggested by some authors.

International audience; Facile and low cost syntheses of 3-mercaptopropionic acid-capped Ag:CdxZn1-xS and of core/shell Ag:CdxZn1-xS/ZnS quantum dots (QDs) are presented. The effects of the Ag+ doping concentration and of the Cd/Zn ratio on the structural and optical properties of the dots were investigated. Core Ag:CdxZn1-xS QDs have an average diameter of ca. 4.5 nm and their photoluminescence (PL) emission can be tuned from 478 to 610 nm by varying the dopant concentration or the composition of the CdxZn1-xS host material. The highest PL quantum yield (25%) is obtained when using 2 or 3.5% doping in Ag+. The PL quantum yield increased substantially (44%) after capping the Ag:CdxZn1-xS core with a ZnS shell. Due to their high photostability and long excited-state lifetimes (1–2 μs), Ag:CdxZn1-xS QDs are of high potential as nanophosphors or as fluorescent probes for bio-imaging.

International audience; extile dyes pose a significant challenge for water pollution due to the poor degradability of their complex aromatic structures (e.g., RR-120 and RBB-150). In order to minimize the harmful effects of RR-120 and RBB-150, the capacity of MgAl-layered double hydroxide for removing of these contaminants was studied herein. Batch adsorption experiments were conducted to investigate the effect of various operating parameters, such as solution pH, contact time, dye concentration, and temperature in order to provide optimal conditions for removal. Structural and morphological analyses were used to highlight the assembly and/or interaction LDH-dye. The state of equilibrium of RR-120 and RBB-150 adsorption was pH- and temperature-dependent and followed the pseudo-second-order rate model. Also, the equilibrium adsorption data of both dyes were found to adopt the Langmuir type isotherm model, which assumes a monolayer arrangement in LDH-dye. Furthermore, the effects of four major coexisting and competing mono- and divalent interlayer anions, such as NO3-, Cl-, CO32-, and SO42-, on the uptakes of RR-120 and RBB-150 were studied and the results showed that NO3- anions had insignificant effect on the uptakes of RR-120 and RBB-150 by MgAl. An equivalent study on the presence of both dyes in competitive trial adsorption/desorption from binary aqueous solution was investigated. And finally, the reuse operation of recovered material after dye adsorption was tested in up to 5 cycles of recyclability.

International audience; 3-Mercaptopropionic acid capped core/shell ZnS:Cu(3%)/ZnS doped quantum dots (QDs) where synthesized at 95 °C in basic aqueous solution using the nucleation doping approach methods. The structural and optical properties of the QDs were characterized by X-ray diffraction (XRD) which confirms the cubic phase blende, whereas transmission electron microscopy (TEM) which shows the nanoparticles are spherical. UV–vis spectroscopy and photoluminescence (PL) spectroscopy. The obtained nearly monodisperse QDs have an average diameter of ca. 3.31 nm and a zinc blende crystal structure. The PL emission wavelength was limited between 500 and 510 nm but PL quantum efficiency of ZnS:Cu/ZnS core/shell nanocrystals increased up to 5%. The experimental results demonstrate that this method is effective for the preparation of ZnS:Cu/ZnS quantum dots.

A series of phosphate-sulfate fluorapatites Ca 10−x Na x (PO 4 ) 6−x (SO 4 ) x F 2 :Eu 3+ (2%) (x = 0, 3, 6) has been synthesized by the solid-state reaction at high temperature. The samples were characterized by X-ray diffraction, Infrared spectroscopy and Raman scattering spectroscopy. Eu 3+ luminescence properties were investigated at 77 K using site selective and time-resolved spectroscopy. Lifetimes and the color points were calculated. The emission spectra and luminescence decays of Eu 3+ ions indicate that there is an energy transfer between different sites occupied by Eu 3+ .

International audience; In this work we focus on the study of the acoustic and mechanical behavior of compressed earth blocks (CEBs). The aim was to study the influence of compaction pressure on the compressive strength and intrinsic acoustic parameters influencing sound absorption of these materials (porosity, tortuosity, airflow resistivity, viscous characteristic length). Specimens made by varying the applied compaction pressure and therefore having various bulk densities were studied. Low bulk density CEBs where stabilized by adding 15% cement. The acoustic absorption coefficients of the different specimens were determined experimentally employing data obtained using the Kundt tube. The intrinsic acoustic parameters were identified by minimizing the discrepancies between the experimentally measured absorption coefficient (α) and the theoretical one modeling the CEBs using the equivalent fluid model. The results showed that the acoustic and mechanical behavior of CEBs were strongly influenced by the applied compaction pressure including, inter alia, the bulk density of the specimen and the added cement used as stabilizer.

This study aimed to investigate the antiulcer and antioxidant activities of myrtle berry seed aqueous extract (MBSAE) in a peptic ulcer model induced by ethanol in male Wistar rats. MBSAE is rich in total polyphenols, total flavonoids, and unsaturated fatty acids, particularly linoleic (18:2) and oleic (18:1) acids. MBSAE also exhibited in vitro antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH) (IC50= 172.1 μg/mL) and superoxide anion (IC50= 200.24 μg/mL) scavenging activities. In vivo, MBSAE provided dose-dependent protection against ethanol-induced gastric and duodenal macroscopic and histological alterations. Also, it inhibited secretory profile disturbances and lipid peroxidation, and preserved normal antioxidant enzyme activities and nonenzymatic antioxidant levels. More importantly, we showed that acute alcohol intoxication increased gastric and duodenal calcium, hydrogen peroxide, and free iron levels, whereas MBSAE treatment protected against intracellular mediator deregulation. In conclusion, we suggest that MBSAE has potent protective effects against alcohol-induced peptic ulcer in rat. This protection might be related in part to its antioxidant properties as well as its opposite effects on some studied intracellular mediators.

International audience; To address security issues in oilwell drillstring system, the drilling operation handling which is in generally not autonomous but ensured by an operator may be drill bit destructive or fatal for the machine. To control of stick-slip phenomenon, the drillstring control at the right speed taking only the drillstring vibration is not sufficient as the mud dynamics and the pressure change around the drill pipes cannot be neglected. A coupled torsional vibration and pressure model is presented, and the well-posedness problem is addressed. As a Partial Differential Equation-Ordinary Differential Equation (PDE-ODE) coupled system, and in order to maintain a non destructive downhole pressure, we investigate the control stability with and without the damping term in the wave PDE. In terms of, the torsional variable, the downhole pressure, and the annulus pressure, the coupled system equilibrium is shown to be exponentially stable.

International audience; This paper presents a nonlinear control scheme to stabilize the problem of torsional vibration suppression with boundary impulsive conditions. A new nonlinear dynamical system is developed. Based on semi-group theory, we prove the well-posednes of the proposed system. In the model development, nonlinearities that arise due to dry friction and loss of contact is considered. Therefore, the impulsive system stability analysis is carried out by using Lyapunov theory and a comparison method. Numerical simulations show the relevance of our result for impulsive system.