Quantitative Games under Failures

We study a generalisation of sabotage games, a model of dynamic network games introduced by van Benthem. The original definition of the game is inherently finite and therefore does not allow one to model infinite processes. We propose an extension of the sabotage games in which the first player (Runner) traverses an arena with dynamic weights determined by the second player (Saboteur). In our model of quantitative sabotage games, Saboteur is now given a budget that he can distribute amongst the edges of the graph, whilst Runner attempts to minimise the quantity of budget witnessed while completing his task. We show that, on the one hand, for most of the classical cost functions considered in the literature, the problem of determining if Runner has a strategy to ensure a cost below some threshold is EXPTIME-complete. On the other hand, if the budget of Saboteur is fixed a priori, then the problem is in PTIME for most cost functions. Finally, we show that restricting the dynamics of the game also leads to better complexity

Energy Localization in Periodic Structures: Application to Centrifugal Pendulum Vibration Absorber

International audienceIn this paper we study the non-linear dynamic of centrifugal pendulum vibration absorbers (CPVA), and we pay a special a ention to localized state solutions. e prediction of such states of vibration, and their stability, is of particular importance because they can lead to inefficient behavior for the CPVA and/or unforeseen stress levels. Using an approximated equation for the pendulums dynamics, we derive initial conditions to put the system in localized states. Following an analytic study of the non-linear normal mode of the system, the resolution of the approximated equation is carried out in the frequency domain using the Harmonic Balance Method and the Asymptotic Numeric Method. For sufficiently low inertia ratio, we show that the system can possess stable localized states

C*-pseudo-multiplicative unitaries and Hopf C*-bimodules

We introduce C*-pseudo-multiplicative unitaries and concrete Hopf C*-bimodules for the study of quantum groupoids in the setting of C*-algebras. These unitaries and Hopf C*-bimodules generalize multiplicative unitaries and Hopf C*-algebras and are analogues of the pseudo-multiplicative unitaries and Hopf--von Neumann-bimod-ules studied by Enock, Lesieur and Vallin. To each C*-pseudo-multiplicative unitary, we associate two Fourier algebras with a duality pairing, a C*-tensor category of representations, and in the regular case two reduced and two universal Hopf C*-bimodules. The theory is illustrated by examples related to locally compact Hausdorff groupoids. In particular, we obtain a continuous Fourier algebra for a locally compact Hausdorff groupoid.Comment: 50 pages; this is a substantial revision and expansion of the preprint "C*-pseudo-multiplicative unitaries" (arXiv:0709.2995) with many new result

PROACTIVE MANAGEMENT OF CUSTOMER NETWORKS FOR STABILITY AND RELIABILITY LEVERAGING APPDY INTEGRATION INTO NETWORK SERVICE PRODUCTS

Techniques are described for leveraging the integration of the AppDynamics (AppDy) Software Development Kit (SDK) with network service products that allows for run-time retrieval of key process data on an AppDy platform. The run-time retrieval of key process data will be managed by a network service provider\u27s customer support teams, which can proactively detect customer network degradations before they have an impact on end user experience

Cold Acclimation Favors Metabolic Stability in Drosophila suzukii

The invasive fruit fly pest, Drosophila suzukii, is a chill susceptible species, yet it is capable of overwintering in rather cold climates, such as North America and North Europe, probably thanks to a high cold tolerance plasticity. Little is known about the mechanisms underlying cold tolerance acquisition in D. suzukii. In this study, we compared the effect of different forms of cold acclimation (at juvenile or at adult stage) on subsequent cold tolerance. Combining developmental and adult cold acclimation resulted in a particularly high expression of cold tolerance. As found in other species, we expected that cold-acclimated flies would accumulate cryoprotectants and would be able to maintain metabolic homeostasis following cold stress. We used quantitative target GC-MS profiling to explore metabolic changes in four different phenotypes: control, cold acclimated during development or at adult stage or during both phases. We also performed a time-series GC-MS analysis to monitor metabolic homeostasis status during stress and recovery. The different thermal treatments resulted in highly distinct metabolic phenotypes. Flies submitted to both developmental and adult acclimation were characterized by accumulation of cryoprotectants (carbohydrates and amino acids), although concentrations changes remained of low magnitude. After cold shock, non-acclimated chill-susceptible phenotype displayed a symptomatic loss of metabolic homeostasis, correlated with erratic changes in the amino acids pool. On the other hand, the most cold-tolerant phenotype was able to maintain metabolic homeostasis after cold stress. These results indicate that cold tolerance acquisition of D. suzukii depends on physiological strategies similar to other drosophilids: moderate changes in cryoprotective substances and metabolic robustness. In addition, the results add to the body of evidence supporting that mechanisms underlying the different forms of acclimation are distinct

Numerical antiresonance continuation of structural systems

Tuned dynamic absorbers are usually used to counteract vibrations at a given frequency. Presence of non-linearities causes energy-dependent relationship of their resonance and antiresonance frequencies at large amplitude of motion, which consequently leads to adetuning of the absorber from the targeted frequency. This paper presents a procedure to track an extremum point (minimum or maximum) of nonlinear frequency responses, based on a numerical continuation technique coupled to the harmonic balance method to follow periodic solutions in forced steady-state. It thus enable to track a particular antiresonance. The procedure is tested and applied on some application cases to highlight the resonance and antiresonance behavior in presence of geometrically non-linear and/or inertial interactions

Games on graphs with a public signal monitoring

We study pure Nash equilibria in games on graphs with an imperfect monitoring based on a public signal. In such games, deviations and players responsible for those deviations can be hard to detect and track. We propose a generic epistemic game abstraction, which conveniently allows to represent the knowledge of the players about these deviations, and give a characterization of Nash equilibria in terms of winning strategies in the abstraction. We then use the abstraction to develop algorithms for some payoff functions.Comment: 28 page

Physiological responses of cold acclimation in Drosophila suzukii

editorial reviewedThe spotted wing drosophila (SWD) Drosophila suzukii is an invasive pest. To control this pest, information about its cold tolerance is required. Several studies have focused on SWD overwintering strategies and reported increased cold tolerance of winter morph (WM) compared to summer morph (SM). However, underlying mechanisms of this difference are not yet known. Our first goal was to study the impact of WM-inducing conditions on SWD cold tolerance and their metabolites composition. We expected to find an accumulation of cryoprotectant metabolites in cold hardy WM flies. Flies were reared at 25°C to induce SM, or at 10°C to induce WM. Cold tolerance was assayed by measuring survival after a stress at -5°C/1h40, minimal critical temperature and chill coma recovery. All metrics confirmed that WM-inducing conditions deeply promoted cold tolerance. SM and WM metabotypes were compared using target and quantitative GC/MS profiling. WM were characterized by an accumulation of several carbohydrates and amino acids, but quantitative changes were rather small (max 6 fold-change). Because robustness in metabolic networks is supposed to be a key element of cold tolerance, we assessed whether different levels of cold acclimation would favor metabolic stability. We generated four different phenotypes: development at 10°C to generate WM that were next acclimated as adults for 7 days at 10 or 25°C (WM10 or WM25) and development at 25°C to generate SM that were next acclimated as adults for 7 days at 10 or 25°C (SM10 or SM25). Using the same measures of cold tolerance, we found that cold tolerance ranked as follow: WM10>SM10>WM25>SM25. Stability of metabolic homeostasis was assessed in these four phenotypic groups using time-series GC/MS profiling. We monitored profiles before, right after, 4h, 8h or 12h after an acute cold shock. During recovery, both WM25 and SM25 metabotypes strongly deviated from origin, and did not return to initial state. This alteration was correlated with uncontrolled augmentation of the total amount of amino acids, which is symptomatic of cold injuries. WM10 presented the strongest temporal stability of metabolic profiles, suggesting a capacity to maintain homeostasis in this cold hardy phenotype. Finally, SM10 presented an intermediate response (as for cold tolerance). Data suggest that the proximal acclimation treatment (ie. at adult stage) is more critical in promoting cold tolerance that acclimation during development. Data corroborate that cold hardiness is associated to metabolic stability during stress and recovery. These results give new information to understand SWD cold tolerance

Cardiac metabolic deregulation induced by the tyrosine kinase receptor inhibitor sunitinib is rescued by endothelin receptor antagonism

International audienceThe growing field of cardio-oncology addresses the side effects of cancer treatment on the cardiovascular system. Here, we explored the cardiotoxicity of the antiangiogenic therapy, sunitinib, in the mouse heart from a diagnostic and therapeutic perspective. We showed that sunitinib induces an anaerobic switch of cellular metabolism within the myocardium which is associated with the development of myocardial fibrosis and reduced left ventricular ejection fraction as demonstrated by echocardiography. The capacity of positron emission tomography with [ 18 F]fluorodeoxyglucose to detect the changes in cardiac metabolism caused by sunitinib was dependent on fasting status and duration of treatment. Pan proteomic analysis in the myocardium showed that sunitinib induced (i) an early metabolic switch with enhanced glycolysis and reduced oxidative phosphorylation, and (ii) a metabolic failure to use glucose as energy substrate, similar to the insulin resistance found in type 2 diabetes. Co-administration of the endothelin receptor antagonist, macitentan, to sunitinib-treated animals prevented both metabolic defects, restored glucose uptake and cardiac function, and prevented myocardial fibrosis. These results support the endothelin system in mediating the cardiotoxic effects of sunitinib and endothelin receptor antagonism as a potential therapeutic approach to prevent cardiotoxicity. Furthermore, metabolic and functional imaging can monitor the cardiotoxic effects and the benefits of endothelin antagonism in a theranostic approach