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Abstract The serotonergic system plays a key modulatory role in the brain. This system is critical in many drug developments for brain disorders via interactions with the 14 subtypes of 5-HT receptors or through reuptake blockade. Positron emission tomography (PET) is an efficient tool for in vivo studies of physiological and pathological processes. Because of its pertinent radiochemical properties, fluorine-18 is one of the most used radioisotopes in PET imaging. This chapter will propose an overview of the 18F-radioligands targeting serotonin receptors, which have been developed over the last few years. Both radiosyntheses and pharmacological properties of these radiotracers will be described, with a specific emphasis on their potential medical applications.

International audience; An important problem in secure multi-party computation is the design of protocols that can tolerate adversaries that are capable of corrupting parties dynamically and learning their internal states. In this paper, we make significant progress in this area in the context of password-authenticated key exchange (PAKE) and oblivious transfer (OT) protocols. More precisely, we first revisit the notion of projective hash proofs and introduce a new feature that allows us to explain any message sent by the simulator in case of corruption, hence the notion of Explainable Projective Hashing. Next, we demonstrate that this new tool generically leads to efficient PAKE and OT protocols that are secure against semi-adaptive adversaries without erasures in the Universal Composability (UC) framework. We then show how to make these protocols secure even against adaptive adversaries, using \emph{non-committing encryption}, in a much more efficient way than generic conversions from semi-adaptive to adaptive security. Finally, we provide concrete instantiations of explainable projective hash functions that lead to the most efficient PAKE and OT protocols known so far, with UC-security against adaptive adversaries, with or without erasures, in the single global CRS setting.As an important side contribution, we also propose a new commitment scheme based on DDH, which leads to the construction of the first one-round PAKE adaptively secure under plain DDH without pairing, assuming reliable erasures, and also improves previous constructions of OT and two- or three-round PAKE schemes.

International audience; In this paper, we provide a necessary clarification of the good security properties that can be obtained from parallel implementations of masking schemes. For this purpose, we first argue that (i) the probing model is not straightforward to interpret, since it more naturally captures the intuitions of serial implementations, and (ii) the noisy leakage model is not always convenient, e.g. when combined with formal methods for the verification of cryptographic implementations. Therefore we introduce a new model, the bounded moment model, that formalizes a weaker notion of security order frequently used in the side-channel literature. Interestingly , we prove that probing security for a serial implementation implies bounded moment security for its parallel counterpart. This result therefore enables an accurate understanding of the links between formal security analyses of masking schemes and experimental security evaluations based on the estimation of statistical moments Besides its consolidating nature, our work also brings useful technical contributions. First, we describe and analyze refreshing and multiplication algorithms that are well suited for parallel implementations and improve security against multivariate side-channel attacks. Second, we show that simple refreshing algorithms (with linear complexity) that are not secure in the continuous probing model are secure in the continuous bounded moment model. Eventually, we discuss the independent leakage assumption required for masking to deliver its security promises, and its specificities related to the serial or parallel nature of an implementation.

We study an annealed model of Uniform Infinite Planar Quadrangulation (UIPQ) with an infinite two-sided self-avoiding walk (SAW), which can also be described as the result of glueing together two independent uniform infinite quadrangulations of the half-plane (UIHPQs). We prove a lower bound on the displacement of the SAW which, combined with the estimates of [15], shows that the self-avoiding walk is diffusive. As a byproduct this implies that the volume growth exponent of the lattice in question is 4 (as is the case for the standard UIPQ); nevertheless, using our previous work [9] we show its law to be singular with respect to that of the standard UIPQ, that is – in the language of statistical physics – the fact that disorder holds.

Increases in arterial stiffness and pulse pressure are typical features of the arterial stiffness during aging and are associated with increased risk of cardiovascular complications. Cellular and molecular determinants of arterial stiffness have not been completely elucidated. Clinically, the carotid-femoral pulse wave velocity (PWV) is the gold standard parameter of arterial stiffness. A recent genome-wide scan of the Framingham Heart Study population has shown that arterial stiffness and mean and pulsatile components of blood pressure are heritable and map to separate the genetic loci in humans, suggesting that distinct genes may modulate these two phenotypes. This chapter details the recent knowledge on the influence of genetic determinants and telomere length on the development of age-related phenotypes. Recent genetic studies have revealed specific genes contributing to arterial stiffening. Available data on genome-wide association (GWA) have been initiated on PWV and have identified common genetic variation in specific loci or single-nucleotide polymorphisms (SNP) significantly associated with PWV. Telomere length at birth is strongly determined genetically and is the main determinant of leukocytes’ telomere length (LTL) later in life. Short LTL is associated with increased risk of stiffness and atherosclerosis of the carotid artery, atherosclerotic heart disease, and diminished survival in the elderly.

International audience; In this paper, we study the effect of smartphone camera exposure on the performance of optical camera communications (OCC) link. The exposure parameters of image sensor sensitivity (ISO), aperture and shutter speed are included. A static OCC link with a 8 × 8 red, green and blue (RGB) LED array employed as the transmitter and a smartphone camera as the receiver is demonstrated to verify the study. Signal-to-noise ratio (SNR) analysis at different ISO values, the effect of aperture and shutter speed on communication link quality is performed. While SNRs of 20.6 dB and 16.9 dB are measured at 1 m and 2 m transmission distance, respectively for a ISO value of 100, they are decreased to 17.4 dB and 13.32 dB for a ISO of 800. The bit error rate (BER) of a 1 m long OCC link with a camera's shutter speed of 1/6000 s is 1.3 × 10 −3 (i.e., below the forward error correction BER limit of 3.8 × 10 −3) and is dropped to 0.0125 at a shutter speed of 1/20 s. This study provides insight of the basic smartphone settings and the exposure adjustment for further complex OCC links.

International audience; Based on a synthesis of findings from psychology, neuroscience, and machine learning, we propose a unified theory of curiosity as a form of motivated cognition. Curiosity, we propose, is comprised of a family of mechanisms that range in complexity from simple heuristics based on novelty, salience, or surprise, to drives based on reward and uncertainty reduction and finally, to self-directed metacognitive processes. These mechanisms, we propose, have evolved to allow agents to discover useful regularities in the world ! steering them toward niches of maximal learning progress and away from both random and highly familiar tasks. We emphasize that curiosity arises organically in conjunction with cogni- tion and motivation, being generated by cognitive processes and in turn, motivating them. We hope that this view will spur the systematic study of curiosity as an integral aspect of cognition and decision making during development and adulthood.

Part 6: Network Modeling; International audience; Mobile Adhoc Networks (MANET) are susceptible to jamming attacks which can inhibit data transmissions. There has been considerable work done in the detection of external jamming attacks. However, detection of insider jamming attack in MANET has not received enough attention. The presence of an insider node that has constantly monitored the network and is privy to the network secrets can acquire sufficient information to cause irreparable damage. In this paper we propose a framework for a novel reputation-based coalition game between multiple players in a MANET to prevent internal attacks caused by an erstwhile legitimate node. A grand coalition is formed which will make a strategic security defense decision by depending on the stored transmission rate and reputation for each individual node in the coalition. Our results show that the simulation of the reputation-based coalition game would help improve the network’s defense strategy while also reducing false positives that results from the incorrect classification of unfortunate legitimate nodes as insider jammers.