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Ricardo Pereira Nogueira,1,2 Jose Deuzimar Uchoa,3,4 Fanny Hilario,2 Gabriela de Fátima Santana-Melo,5 Luana Marotta Reis de Vasconcellos,5 Fernanda Roberta Marciano,6 Virginie Roche,2 Alberto Moreira Jorge Junior,2,7 Anderson Oliveira Lobo4 1Chemical Engineering Department, Khalifa University of Science and Technology, Abu Dhabi 127788, United Arab Emirates; 2Université Grenoble Alpes, Université Savoie Mont Blanc, CNRS, GrenobleINP*LEPMI, Grenoble 38000, France; 3Federal Institute of Education, Science and Technology of Piauí, Teresina 64053-390, Brazil; 4Interdisciplinary Laboratory for Advanced Materials, BioMatLab Group, Materials Science and Engineering Graduate Program, UFPI – Federal University of Piaui, Teresina 64049-550 Brazil; 5Department of Bioscience and Oral Diagnosis, Institute of Science and Technology, Sao Paulo State University, Sao José dos Campos 12245-000, Brazil; 6Department of Physics, Federal University of Piaui, Teresina PI 64049-550 Brazil; 7Department of Materials Engineering, Federal University of São Carlos, São Carlos 13565-905, BrazilCorrespondence: Anderson Oliveira LoboCampus Universitário Ministro Petrônio Portella, Av. Universitária, s/n, Centro de Tecnologia, Laboratório Interdisciplinar de Materiais Avançados, Ininga, Teresina, PI 64049-550, BrazilTel +55 86 32371057Email lobo@ufpi.edu.brBackground: Nanostructured surface modifications of Ti-based biomaterials are moving up from a highly-promising to a successfully-implemented approach to developing safe and reliable implants.Methods: The study’s main objective is to help consolidate the knowledge and identify the more suitable experimental strategies related to TiO2 nanotubes-modified surfaces. In this sense, it proposes the thorough investigation of two optimized nanotubes morphologies in terms of their biological activity (cell cytotoxicity, alkaline phosphatase activity, alizarin red mineralization test, and cellular adhesion) and their electrochemical behavior in simulated body fluid (SBF) electrolyte. Layers of small-short and large-long nanotubes were prepared and investigated in their amorphous and crystallized states and compared to non-anodized samples.Results: Results show that much more than the surface area development associated with the nanotubes’ growth; it is the heat treatment-induced change from amorphous to crystalline anatase-rutile structures that ensure enhanced biological activity coupled to high corrosion resistance.Conclusion: Compared to both non-anodized and amorphous nanotubes layers, the crystallized nano-structures’ outstanding bioactivity was related to the remarkable increase in their hydrophilic behavior, while the enhanced electrochemical stability was ascribed to the thickening of the dense rutile barrier layer at the Ti surface beneath the nanotubes.Keywords: surface modification, TiO2 nanotubes, commercially pure titanium, bioactivity

The paleogeographic position of the central Dodecanese Islands at the transition between the Aegean and Anatolian plates plays a considerable role in understanding the link between both geologically unique domains. In this study, we investigate the tectonic history of the central Dodecanese Islands and the general correlation with the Aegean and western Anatolian and focus on the poorly studied islands of Kalymnos and Telendos. Three different major tectonic units were mapped on both islands from bottom to top: (1) The Kefala Unit consists of late Paleozoic, fossil-rich limestones, which have been deformed into a SE-vergent fold-and-thrust belt sealed by an up to 200-m-thick wildflysch-type olistostrome with marble and ultramafic blocks on a scale of tens of meters. (2) The Marina Basement Unit consists of a Variscan amphibolite facies basement with garnet mica schists, quartzites, and amphibolites. (3) Verrucano-type formation violet shales and Mesozoic unmetamorphosed limestones form the Marina Cover Unit. Correlation of these units with other units in the Aegean suggests that Kalymnos is paleogeo-graphically located at the southern margin of the Pelagonian domain, and therefore it was in a structurally upper tectonic position during the Paleogene Alpine orogeny. New white mica 40Ar/39Ar ages confirm the Carboniferous deformation of the Marina Basement Unit followed by a weak Triassic thermal event. Single-grain white mica 40Ar/39Ar ages from pressure solution cleavage of the newly defined Telendos Thrust suggest that the Marina Basement Unit was thrusted toward the north on top of the Kefala Unit in the Paleocene. Located at a tectonically upper position, the units exposed in the central Dodecanese escaped subduction and the syn-orogenic, high-pressure metamorphism. However, these units were affected by post-orogenic extension, and the contact between the Marina Basement Unit and the non-metamorphic Marina Cover Unit has been reactivated by the cataclastic top-to-SSW, low-angle Kalymnos Detachment. Zircon (U-Th)/He ages from the Kefala and Marina Basement Units are ca. 30 Ma, which indicates that exhumation and cooling below the Kalymnos Detachment started in the Oligocene. Conjugate brittle high-angle normal fault systems, which resulted in the formation of four major WNW-ESE-trend-ing graben systems on Kalymnos, localized mainly in the Marina Cover Unit and probably rooted in the mechanically linked Kalymnos Detachment. Since Oligo-Miocene deformation in the northern Dodecanese records top-to-NNE extension and the Kalym-nos Detachment accommodated top-to-SSW extension, we suggest that back-arc extension in the whole Aegean realm and transition to the Anatolian plate is bivergent. © 2022 Geological Society of America. All Rights Reserved.

The influence of chromium concentration and partial crystallization on the corrosion resistance of the FeCrNiB amorphous alloys was investigated. The samples were produced by melt-spinning equipment. Vacuum heat treatments were used for partial and total crystallization. The study methods used were: X-ray diffraction, differential scanning calorimetry, transmission electron microscopy, and electrochemical tests in high salt concentration media. The results revealed that the concentration of chromium in FeCrNiB amorphous alloys could be reduced significantly, still providing passive film stability. They also show that partial crystallization of FeCrNiB alloys may not be deleterious to the corrosion properties, opening important possibilities for the development of high-performance coatings.

International audience; We conducted a microstructural analysis of bedding-parallel faults (BPFs) in Mesozoic clay-rich layers of the Southeast Basin of France. Various microstructures are recognized in thin sections under a petrographic microscope and by cathodoluminescence. The microscale observations are combined with outcrop observations from previous studies to provide insight into the origin of the BPFs and their evolution during successive phases of deformation in a basin that had a polyphase tectonic history. The BPFs slipped while normal faults were formed during the Oligocene extension. Then, another phase of slip occurred later during the basin inversion. These two phases of deformation are expressed by recurrent crack-seal veins, pull-apart veins and stylolites. In addition, calcite veins with an elongate blocky morphology suggest an opening normal to bedding before the reactivation. The BPFs initiated in clay layers that were shallow dipping. Such conditions may appear mechanically unfavourable for an opening normal to bedding or a shearing parallel to bedding. We suggest that the role of rock anisotropy is critical. This study furthermore demonstrates that BPFs can be long-lived brittle structures that may record successive tectonic events.

The active, open-cast, lignite mines in the Ptolemais Basin, NW Greece, provide world-class outcrops for characterising and understanding normal fault systems from km- down to mm-scale. We have visited and mapped these mines 26 times at ca. 3 month intervals since October 2009. The data collected during each fieldwork campaign were structural measurements, interpretations, various resolutions of photographs and GPS locations for all exposed faults and related structures observed in each mine. Part of this unique dataset has been imported within a fully georeferenced 3D structural interpretation package and has been used for fault and horizon interpretations. Our motivation for this work is to advance our generic understanding of the structure and development of normal faults, but in this contribution, we focus on some of our findings that might be of more general interest to mine planners and designers

Slab tearing below western Turkey had first-order tectonic and magmatic consequences by inducing a lateral gradient of extension in the upper plate and toroidal flow of asthenosphere that affected the typology and distribution of melts at the surface. But the coupling mechanisms between the 3D mantle flow at depth and deformation in the upper plate above a slab tear have received little attention so far. This paper is focused on the description of the distribution and kinematics of deformation in the eastern part of the Aegean Sea, within the transition zone between the Cyclades and the Menderes Massif, which have been little studied. By investigating the Dodecanese and Eastern Aegean islands, we thus complete the description of the extensional strain field in the overriding plate around the slab tear. There, extension related to slab retreat and tearing keeps a constant NNE-SSW direction accommodating the difference in finite rates of extension, without localized crustal-scale strike-slip faults and block rotations above the tear. In addition, despite the complexity involved in the Aegean-Anatolian orogenic wedge, a similar structural position is recognized through the entire region. From top to bottom, we found that (i) the Lycian units which were exhumed earlier, in the Late Cretaceous, (ii) the higher-pressure and higher-temperature units (i.e. the Upper Cycladic Blueschist Nappe), with exception of the Vourliotes nappe in Samos, and finally (iii) the colder units such as Amorgos unit, the Menderes and its cover before the Main Menderes Metamorphism overprint and the Lower Cycladic Blueschist Nappe (e.g. Milos, Folegandros, a part of the Dodecanese and Fourni islands). © 2019 Elsevier B.V.

Résumé du poster présenté.; Chlorinous flavors are one of the leading cause of customers’ complaints and dissatisfaction with drinking water. To investigate potential regional differences in chlorine perception, sensory testing experiments were conducted in France and in Spain to assess consumers’ sensory sensitivity (chlorine flavor detection threshold) as well as their liking and acceptance for chlorinated solutions. The chlorine flavor detection threshold was found to vary depending on countries (0.17 mg/LCl2 in France and 0.56 mg/LCl2 in Spain). According to the relation found between chlorine practices and average flavor detection thresholds, it is likely that habituation may support observed sensory differences between the two countries. In addition, consumers’ liking and acceptance for chlorinated water was found to be in agreement to their sensory sensitivity: the higher the detection threshold, the higher the acceptability for chlorinated waters.

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Portland cement has become an essential building material in the last century. Its production unfortunately leads to noticeable CO2-emissions. The development of Belite-Yeelimite-Ferrite (BYF) cement as alternative binder is a promising solution with a decrease of 20-30% in CO2 emissions. One important issue for this new cement is its ability to passivate mild steel. Only few results about it are currently available due to the relatively new nature of the technology. This paper discusses the electrochemical behavior of steel in a BYF matrix. The impact of chloride (present in raw materials as permissible impurities) was considered too. An ordinary Portland cement was used as reference. Mortar specimens with embedded steel rebar were cast with varying chloride contents (0.0, 0.2, 0.4 and 1.0% of chloride by mass of cement). Electrochemical techniques such as half-cell readings, linear polarization resistance (LPR) and large potentiodynamic polarizations were carried out. Specimens contaminated by chloride up to 0.4% showed low corrosion rate (< 1 μm/year) during the first year of measurements. High corrosion activity (>5 μm/year) was yet observed with a chloride content of 1.0% by mass of cement. Therefore steel embedded in BYF mortar passivates and a chloride content up to 0.4% by mass of cement can be tolerated. The contamination by 1% of chloride by mass of cement (not allowed for reinforced concrete made with Portland cement according to the European standard EN 206) leads to active corrosion.

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International audience; Rare individuals can naturally clear chronic hepatitis B virus (HBV) infection and acquire protection from reinfection as conferred by vaccination. To examine the protective humoral response against HBV, we cloned and characterized human antibodies specific to the viral surface glycoproteins (HBsAg) from memory B cells of HBV vaccinees and controllers. We found that human HBV antibodies are encoded by a diverse set of immunoglobulin genes and recognize various conformational HBsAg epitopes. Strikingly, HBsAg-specific memory B cells from natural controllers mainly produced neutralizing antibodies able to cross-react with several viral genotypes. Furthermore, monotherapy with the potent broadly neutralizing antibody Bc1.187 suppressed viremia in vivo in HBV mouse models and led to post-therapy control of the infection in a fraction of animals. Thus, human neutralizing HBsAg antibodies appear to play a key role in the spontaneous control of HBV and represent promising immunotherapeutic tools for achieving HBV functional cure in chronically infected humans.

Extensive opencast lignite mining in the Ptolemais Basin, NW Greece has exposed a plethora of outcrops within a normal fault system offsetting a sequence of interbedded lignites and marls of Pliocene age. The entire length of a 630 m long fault over a vertical interval of 80 m has been mapped in detail from 48 mine faces. The mapped fault comprises 5 fault segments large enough to be mapped in 3D, smaller fault segments exposed on individual mine faces and associated continuous deformation in the form of bed rotations and normal drag. These fault components combined to provide a regular aggregate throw distribution over the mapped fault. The boundaries between adjacent fault segments have a variety of geometries and they may be fully unconnected or they may link along strike or down dip within the fault zone. The fault geometry and throw distribution is analysed using two approaches, a discrete mapping of the large fault segments and a continuous approach based on measures of fault thickness and throw partitioning at individual outcrops. This combination of approaches demonstrates that fault thickness and the proportion of fault throw on the individual fault segments observed on any cross-section through the fault are related almost entirely to fault segmentation in 3D.

Normal faults often comprise arrays of fault segments. The boundaries between adjacent fault segments, relay zones and relay ramps can be of crucial importance to fluid migration pathways across and along faults and for across-fault reservoir juxtaposition. However, despite the increased number of studies of faults in high quality 3D seismic data, the three dimensional geometric or kinematic properties of relay zones or the controls on their 3D geometry are still unclear. This contribution investigates the characteristics of three dimensional segmentation based on an extensive collection of normal faults and relay zones in different geological settings. Our analysis shows that relay zones most often develop by bifurcation from a single fault surface but can also arise from the formation of segments which are disconnected in 3D from their inception. Relay zones generally occur between fault segments that step in the dip or strike direction, and intermediate oblique relay zones are less frequent. When combined together, these different geometries can form a complex spectrum of fault segmentation, whose characteristics can be related to underlying geological controls, such as the mechanical heterogeneity of the faulted sequence and the influence of the basement structure

Partitioning of fault displacement onto multiple segments within a fault mapped as a single structure on seismic can result in flow paths between seemingly unconnected fault-bound compartments. The problem can be tackled using a quantitative fault zone description underlain by three parameters that have been characterised for a variety of natural fault systems. Methods for deriving these parameters for subsurface datasets are outlined, and a range of analytical and modelling approaches for assessing the likely importance of sub-seismic fault segmentation in an exploration and production context are discussed and illustrated

International audience; Slab rollback results in the development of low-angle normal faults (detachments) and metamorphic core complexes (MCCs) in back-arc domains. Although the mechanical consequences of slab dynamics on lithospheric and crustal behaviors have already been studied, thermal effects have not been investigated yet. This study shows that slab rollback produces lithospheric-scale thermal perturbations intrinsically associated with emplacement of amagmatic high-enthalpy geothermal systems. Using a multi-scale numerical modeling approach, with lithospheric-scale 3-D thermo-mechanical models of subduction, and 2-D models of fluid flow at the scale of detachments, we demonstrate that subduction-induced extensional tectonics controls the genesis and distribution of crustal-scale thermal domes from the base of the crust, and the location of high-energy geothermal systems. We find that when slab tearing occurs, Moho temperatures can temporarily increase by up to 250 °C due to significant shear heating in the flowing upper mantle. Associated thermal anomalies (with characteristic width and spacing of tens and hundreds of km, for crustal and lithospheric scales, respectively) then migrate systematically toward the retreating trench. These thermal domes weaken the crust, localize deformation and enhance the development of crustal-scale detachments. These thermo-mechanical instabilities mimic genesis of high-temperature MCCs with migmatitic cores in the back-arc domain, such as those of the Menderes (western Anatolia, Turkey) and Larderello (southern Tuscany) provinces in the Mediterranean realm, and those in the Basin and Range (western United States), where detachments control the bulk of the heat transport. At the scale of MCCs, the bulk fluid flow pattern is controlled by topography-driven flow while buoyancy-driven flow dominates within the permeable detachments, focusing reservoir location of high-energy geothermal systems at shallow depth beneath the detachments.