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Positron Emission Tomography (PET) can support a diagnosis of neurodegenerative disorder by identifying disease-specific pathologies. Our aim was to investigate the feasibility of using activity reduction in clinical [A total of 162 patients with clinically uncertain Alzheimer's disease underwent amyloid [Noise reduction of low-activity PET images was successful for both cohorts using 5% of the original activity with improvement in visual quality and all similarity metrics with respect to the ground-truth images. Clinically relevant metrics extracted from the low-activity images deviated 2% compared to ground-truth values, which were not significantly changed when extracting the metrics from the denoised images.The presented models were based on the same network architecture and proved to be a robust tool for denoising brain PET images with two widely different tracer distributions (delocalized, ([

In the field of automatic quality or safety assurance level evaluation, this paper proposes the first approach towards the automation of the modelling processes of both the valid and faulty state machines within a SoC (System-on-a-Chip). The choice of using the modelling framework of APSYS guarantees the possibility to model beyond the classical electromechanical systems, exploring the MBSA applied to SoC. Experimental results have been conducted on an I2C-AHB and SPI-AHB systems, laying the base for a more complete and extended analysis of complex digital systems, defining the basis to ensure the scalability of the model, crucial when approaching heavily interconnected systems as those belonging to the digital world.

Exploration success in fold-and-thrust belts, like the Potwar petroleum province, is impacted by seismic imaging challenges and structural complexity. Success partly relies on the ability to validate subsurface models and model a range of properties, such as reservoir permeability. This is particularly important in the case of tight carbonate reservoirs such as the Eocene Sakesar Formation, where the recovery of economic quantities of hydrocarbons is conditioned by the presence of fracture-enhanced permeability. This requires the application of geological and geophysical modeling techniques to address these challenges, to minimize uncertainty and drive exploration success. The interpretation and structural validation of the Ratana structure presented here allows the proposal of a consistent and robust structural model even in areas of higher uncertainty in the data, such as along faults. The dynamically updatable, watertight, complex 3D structural framework created for the top Sakesar reservoir was used in combination with an assisted fault interpretation algorithm to characterize the fault and fracture pattern. The results showed a higher density of high amplitude fractures on the flanks of the structure rather than along the hinge. These results are supported by the incremental strain modeling based on the kinematic evolution of the structure. Together, this helped to characterize potential fracture corridors in areas of the seismic volume that previously proved challenging for human driven interpretation. Our results allow us to reduce the uncertainty related to the geometrical characteristics of the reservoir and provide insights into potential exploration well targets to maximize chances of success, suggesting that permeability and hydrocarbon flow may be higher at the margins of the Ratana structure, and not at the crest, which was the focus of previous exploration and production efforts.

In the framework solving electromagnetic scattering problems with a Leontovich impedance boundary condition (LIBC), the numerical resolution requires the evaluation of singular integrals appearing in the discretization of the variational formulation. Our main interest is to pricisely evaluate these integrals. Thus, we propose an analytic method to approximate it. The performance of this method will be evaluated by calculating the radar cross section (RCS). Then, we compare RCS to the Mie series solution for the unit sphere in various configurations.

With the rise of the use of CPU-based Systems on a Chip (SoCs) in critical applications, the need to comply with harsh environments such as radiations or environmental fluctuation of parameters where they will evolve is essential. Devices must be qualified using Accelerated Soft-Error Rate (ASER). They are irradiated with neutrons, heavy ions, protons, or alpha particles depending on the mission profile. In addition, high frequency and complex computing tasks make SoCs difficult to observe and origin of errors difficult to identify. Radiation-induced Single-Event Effects (SEEs) are then hard to interpret. In this paper we present the Fail-Reason Capture (FIRECAP) Intellectual Property (IP). This IP is embedded in a SoC and allows probing and recording processor resources. Recording is controlled by hardware watchpoints that are triggering actions when hit. In addition, illegal jump traps have been added in the memory, such as deadcode traps around program loops and Error Capturing Instructions (ECI) spread in unused memory. The FIRECAP IP is interfaced to a RISC-V based SoC. Probes are implemented on the PC, IR, SP and RA registers of the processor. Two SoCs are integrated in a 28-nm FDSOI test chip. The failure mode coverage and observation points have been evaluated through a fault injection campaign done in simulation, then experiments using Electromagnetic Fault Injection (EMFI) on the device are presented.

International audience; In the field of automatic quality or safety assurance level evaluation, this paper proposes the first approach towards the automation of the extraction processes of both the valid and faulty state machines within a System-on-a-Chip. The data automatically extracted by this method is a relevant input for behavioural modelization and FMEA analysis. The method is based on a semi-automated approach for the systematic extraction of failure modes of a digital design in the hypothesis of a single-event upset (SEU) or stuck-at in flip-flops. This procedure aims to enhance human driven failure analysis and provide inputs for RAMS frameworks in the process of quality assurance of complex devices. The main objective is to transport and apply RAMS methods and tools in the area of SoCs design. Experimental results have been conducted on an I2C - AHB system, laying the base for a complete and more complex analysis on an entire SoC.

The Phanerozoic sedimentary record documents a diverse series of cyclic patterns of sedimentation that reflect multiple drivers of change (e.g. climate, eustasy, tectonics, biotic evolution) operating over a range of time scales (days to hundreds of million years). While short-term cycles can be easily identified within the rock record and have frequently been related to the Milankovitch cycles, medium-term (a few tens of million years) and long-term (hundreds of million years) cycles are less-well-resolved. Notably the identification of medium- and long-term cycles are reliant upon global scale studies, which are typically hampered by low stratigraphic resolution or address sedimentary changes indirectly through proxies (e.g. sea-level models, geochemical trends). Moreover, such difficulties have resulted in uncertainties as to the drivers and durations of medium- and long-term cycles.To adequately address this challenge, an integrated approach is required, combining 1) large sedimentary and global events datasets, 2) a high-resolution sequence stratigraphic model, and 3) plate tectonic and digital palaeo-elevation modelling.We present the preliminary results of an industry-led study of medium- to long-term Phanerozoic cycles in global sedimentation and an assessment of the drivers of these cycles. Our study is based upon a spatially- and temporally-enabled global dataset of sedimentary records, obtained from over 8,500 wells. The sedimentary data contained within the wells have been standardised using a hierarchical classification of sediment types and divided into time slices based upon sequence stratigraphic interpretations, and the identification of age calibrated maximum flooding surfaces derived from the Neftex Global Sequence Stratigraphic Model. This approach allows the Phanerozoic sedimentary record to be subdivided into 132 time slices and the proportion of different sedimentary compositions preserved for each time slice can be reported as a percentage. The resultant analysis identifies medium- to long-term cycles in the proportions of siliciclastics, carbonates and evaporites.There are two long-terms trends apparent from our data, and these have been analysed by a palinspastic reconstruction of each time slice using our digital palaeo-elevation and tectonic models. The first trend is a progressive decrease in the proportion of carbonates relative to siliciclastics, such that carbonates represent ~50% of Cambrian sediments and ~30% of Neogene sediments. This appears linked to early Palaeozoic low latitude continental configurations favouring carbonate sedimentation. The second trend is a notable increase in evaporites from the Late Permian to Late Jurassic (5% to 10%, from a Phanerozoic average of Medium-term cycles are identifiable as significant shifts in the global proportions of siliciclastics relative to carbonates. There is a hierarchical arrangement to these cycles, both in terms of duration and severity of change, suggestive of multiple drivers. An initial comparison with known glaciations, major biotic events impacting carbonate producers and orogenies appears to explain many of these cycles.

International audience; The sites of La Monédière at Bessan and La Cougourlude at Lattes both emerge during the 6th century BC and rapidly act as trading-places withina context where Gallic societies of southern France are tended to structure themselves through the influence of increasing Mediterranean trade.From the time of their rise until their abondonement, their destiny appears to be closely linked to that of nearby port establishments, Agde andLattara. Recent excavations carried out on these two settlements revealed imposing, so far unknown, defensive works. The fortifications of these two sites are compared not only in terms of location and shape, but also as to the circumstances of their dismantling. Although the primary goalof these works was control and protection, several characteristics point to deliberately expressed ostentation and a display of symbolic power.; Émergeant tous deux au VIe siècle av. n. è., les sites de La Monédière à Bessan et de La Cougourlude à Lattes font rapidement office de places d’échanges, dans un contexte où, sous l’impulsion du développement du commerce méditerranéen, les sociétés gauloises du Midi tendentà se structurer. Depuis leur essor jusqu’à leur abandon, le destin des deux agglomérations apparaît étroitement lié à celui des établissementsportuaires voisins, Agde et Lattara. Les fouilles récentes menées sur les deux sites de La Monédière et La Cougourlude ont permis d’en aborder l’imposant système défensif, insoupçonné jusqu’alors. Les fortifications des deux sites sont mises en parallèle en examinant le parti-pris de leur implantation, leur morphologie mais également les conditions de leur démantèlement. Si ces ouvrages répondent en premier lieu à un impératifde contrôle et de protection, plusieurs traits témoignent par ailleurs de la volonté d’ostentation qu’ils expriment et de la charge symbolique quileur est conférée.

Numerous techniques for closure of the anterior skull base in cancer patients have a high success rate but management of failure is poorly documented. To standardize the post-operative follow-up after reconstruction surgery of the anterior skull base after removal for sinonasal carcinoma. Retrospective review of failure of anterior skull base reconstruction between 2005 and 2018 in a multicenter setting. Twenty four patients were included. Reconstruction failure was detected by a cerebrospinal (CSF) leak in 79.2%, by an infectious complication without CSF leak (i.e. meningitis) in 12.5%, and in 8.3% by extensive pneumocephalus. Failure was observed during the first week after surgery in 75% of patients, in the second week in 21%, and in 4% after day 15. The delay in discovery of the failure was associated with multilayer reconstruction (p=.03). Failure was treated surgically in 54% of the patients and medically in 46%, with a similar success rate (85 vs. 100%). After carcinologic resection of the anterior skull base, monitoring should be systematic during the first postoperative week. Surgical management of failure is not always necessary.

International audience