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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.

International audience; We study unlimited infinite churn in peer-to-peer overlay networks. Under this churn, arbitrary many peers may concurrently request to join or leave the overlay network; moreover these requests may never stop coming. We prove that unlimited adversarial churn, where processes may just exit the overlay network, is unsolvable. We focus on cooperative churn where exiting processes participate in the churn handling algorithm. We define the problem of unlimited infinite churn in this setting. We distinguish the fair version of the problem, where each request is eventually satisfied, from the unfair version that just guarantees progress. We focus on local solutions to the problem, and prove that a local solution to the Fair Infinite Unlimited Churn is impossible. We then present our algorithm UIUC that solves the Unfair Infinite Unlimited Churn Problem for a linearized peer-to-peer overlay network. We extend this solution to skip lists and skip graphs.

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; This study presents an algebraic method to detect, count, and identify concomitant motions of parallel robots at the velocity level. The pose and orientation of moving platform of parallel manipulators (PMs) with f-DOF could be commonly described by f possible motion variables on the instantaneous motion space (IMS) and (6 − f) restriction motion variables on the instantaneous restriction space (IRS). However, in some situations, PMs moving platform may accompanied by a concomitant (parasitic) motions along the direction of restriction space. Therefore, the commonly understood one-to-one correspondence between joint space and task space mobility of non-redundant PMs would be compromised. This phenomenon occurred due to the fact that the alignment of screws can change the reciprocal screws while the given screw systems are still maintained. To demonstrate the proposed method, an amplitude-based concomitant motion comparison is performed on two widely utilized lower-mobility parallel mechanisms, 3RPS and 3PRS. The result has shown that for the selected mechanisms, concomitant motion is identical regardless of their difference in joint arrangements in each limbs.

International audience; Orchestras of Digital Musical Instruments (DMIs) enable new musical collaboration possibilities, extending those of acoustic and electric orchestras. However the creation and development of these orchestras remain constrained. In fact, each new musical collaboration system or orchestra piece relies on a fixed number of musicians, a fixed set of instruments (often only one), and a fixed subset of possible modes of collaboration. In this paper, we describe a unified framework that enables the design of Digital Orchestras with potentially different DMIs and an expand-able set of collaboration modes. It relies on research done on analysis and classification of traditional and digital orchestras, on research in Collaborative Virtual Environments, and on interviews of musicians and composers. The BOEUF framework consists of a classification of modes of collaboration and a set of components for modelling digital orchestras. Integrating this framework into DMIs will enable advanced musical collaboration modes to be used in any digital orchestra, including spontaneous jam sessions.

International audience; We describe an approach to extract 13C-labeled sugars (glucose, fructose, maltose, sucrose, myo-inositol as well as glucose from starch) from plant tissues and to analyze their isotopomer distribution by gas chromatography–mass spectrometry (GC-MS). Sugars are derivatized with N,O-bis(trimethylsilyl) trifluoroacetamide (BSTFA) into their Si(CH3)3 derivatives. Electronic and chemical ionizations are used to obtain suitable fragments for metabolic flux analysis (MFA). Unique fragments are identified by computer simulation and experimental verification with labeled standards. Linear equations for separating information from glucosyl and fructosyl moieties of sucrose are presented. Finally, mass distributions are corrected for natural isotope abundance using a home-written program. The method is illustrated by sugar isotopomer analysis of 13C-labeled rapeseed embryos.

We discuss the use of parametric phase-diverse phase retrieval to characterize and optimize the transmitted wavefront of a high-contrast apodized pupil coronagraph with and without an apodizer. We apply our method to correct the transmitted wavefront of the HiCAT (High contrast imager for Complex Aperture Telescopes) coronagraphic testbed. This correction requires a series of calibration steps, which we describe. The correction improves the system wavefront from 16 nm RMS to 3.0 nm RMS for the case where a uniform circular aperture is in place. We further measure the wavefront with the apodizer in place to be 11.7 nm RMS. Improvement to the apodized pupil phase retrieval process is necessary before a correction based on this measurement can be applied.

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; Toxoplasma gondii is a highly successful parasite that is thought to infect nearly one third of the world's population. Molecular epidemiology studies have illuminated the population structure of T. gondii strains world-wide and enabled insights into how the parasite is transmitted and the frequency of genetic exchange. Toxoplasma population genetics studies have shown that in North America and Europe, three genotypes have predominated whereas other diverse genotypes have propagated in other parts of the world, particularly in Central and South America. This chapter summarizes the techniques used to understand the population structure of T. gondii and how these techniques have also been helpful in understanding outbreaks of toxoplasmosis. As technology has advanced, more in-depth studies have facilitated our understanding of how differing genotypes can be linked to biological phenotypes including human disease.

International audience; Semidefinite programming (SDP) solvers are increasingly used as primitives in many program verification tasks to synthesize and verify polynomial invariants for a variety of systems including programs, hybrid systems and stochastic models. On one hand, they provide a tractable alternative to reasoning about semi-algebraic constraints. However, the results are often unreliable due to " numerical issues " that include a large number of reasons such as floating-point errors, ill-conditioned problems, failure of strict feasibility, and more generally, the specifics of the algorithms used to solve SDPs. These issues influence whether the final numerical results are trustworthy or not. In this paper, we briefly survey the emerging use of SDP solvers in the static analysis community. We report on the perils of using SDP solvers for common invariant synthesis tasks, characterizing the common failures that can lead to unreliable answers. Next, we demonstrate existing tools for guaranteed semidefinite programming that often prove inadequate to our needs. Finally, we present a solution for verified semidefinite programming that can be used to check the reliability of the solution output by the solver and a padding procedure that can check the presence of a feasible nearby solution to the one output by the solver. We report on some successful preliminary experiments involving our padding procedure.