A Match in Time Saves Nine: Deterministic Online Matching With Delays

We consider the problem of online Min-cost Perfect Matching with Delays (MPMD) introduced by Emek et al. (STOC 2016). In this problem, an even number of requests appear in a metric space at different times and the goal of an online algorithm is to match them in pairs. In contrast to traditional online matching problems, in MPMD all requests appear online and an algorithm can match any pair of requests, but such decision may be delayed (e.g., to find a better match). The cost is the sum of matching distances and the introduced delays. We present the first deterministic online algorithm for this problem. Its competitive ratio is $O(m^{\log_2 5.5})$ $= O(m^{2.46})$, where $2 m$ is the number of requests. This is polynomial in the number of metric space points if all requests are given at different points. In particular, the bound does not depend on other parameters of the metric, such as its aspect ratio. Unlike previous (randomized) solutions for the MPMD problem, our algorithm does not need to know the metric space in advance

Development of expressed sequence tag and expressed sequence tag-simple sequence repeat marker resources for Musa acuminata.

Banana (Musa acuminata) is a crop contributing to global food security. Many varieties lack resistance to biotic stresses, due to sterility and narrow genetic background. The objective of this study was to develop an expressed sequence tag (EST) database of transcripts expressed during compatible and incompatible banana-Mycosphaerella fijiensis (Mf) interactions. Black leaf streak disease (BLSD), caused by Mf, is a destructive disease of banana. Microsatellite markers were developed as a resource for crop improvement

Teriflunomide treatment for multiple sclerosis modulates T cell mitochondrial respiration with affinity-dependent effects

International audienceInterference with immune cell proliferation represents a successful treatment strategy in T cell-mediated autoimmune diseases such as rheumatoid arthritis and multiple sclerosis (MS). One prominent example is pharmacological inhibition of dihydroorotate dehydrogenase (DHODH), which mediates de novo pyrimidine synthesis in actively proliferating T and B lymphocytes. Within the TERIDYNAMIC clinical study, we observed that the DHODH inhibitor teriflunomide caused selective changes in T cell subset composition and T cell receptor repertoire diversity in patients with relapsing-remitting MS (RRMS). In a preclinical antigen-specific setup, DHODH inhibition preferentially suppressed the proliferation of high-affinity T cells. Mechanistically, DHODH inhibition interferes with oxidative phosphorylation (OXPHOS) and aerobic glycolysis in activated T cells via functional inhibition of complex III of the respiratory chain. The affinity-dependent effects of DHODH inhibition were closely linked to differences in T cell metabolism. High-affinity T cells preferentially use OXPHOS during early activation, which explains their increased susceptibility toward DHODH inhibition. In a mouse model of MS, DHODH inhibitory treatment resulted in preferential inhibition of high-affinity autoreactive T cell clones. Compared to T cells from healthy controls, T cells from patients with RRMS exhibited increased OXPHOS and glycolysis, which were reduced with teriflunomide treatment. Together, these data point to a mechanism of action where DHODH inhibition corrects metabolic disturbances in T cells, which primarily affects profoundly metabolically active high-affinity T cell clones. Hence, DHODH inhibition may promote recovery of an altered T cell receptor repertoire in autoimmunity

Semi-empirical correlation function for one and two-ionic component plasmas

This paper proposes a general semi-empirical expression for the correlation function g(y) in the one-component plasma and the two-ionic component plasma cases. The results, in good agreement with Monte Carlo simulations, are deduced from an analytic expression. This formulation permits extensive calculations for ionic mixtures without prohibitive calculation times.Dans cet article une expression générale semi-empirique de la fonction de corrélation g(y) est proposée dans le cas des plasmas à une composante ainsi que des plasmas à deux composantes ioniques. Les résultats, en bon accord avec les calculs de Monte Carlo, sont déduits d'une expression analytique. Cette formulation permet d'entreprendre des calculs pour des mélanges d'ions avec des temps de calcul non prohibitifs

Low-frequency electric microfield calculations by iterative methods

An iterative method using the second moment rule is proposed for the calculation of the low-frequency component of the microfield at a charged point. The results, in good agreement with other recent works, are deduced from a useful and simple numerical simulation. This method permits extensive calculations for ionic mixtures without prohibitive calculation times.Dans cet article, une méthode itérative utilisant la règle du second moment est proposée pour le calcul de la composante basse fréquence du microchamp en un point chargé. Les résultats, en bon accord avec ceux de travaux récents, sont déduits d'une simulation numérique particulièrement simple. Cette méthode permet d'entreprendre des calculs pour des mélanges d'ions avec des temps de calcul non prohibitifs

Electrical investigation of the transverse discharge of U.V. nitrogen gas laser

Simultaneous time-resolved measurements of electrical parameters and laser power density of a transversely excited nitrogen gas laser are analysed. The experimental results were obtained from a short cavity laser device (380 mm active length) operating at low pressure (40 torr) and producing up to 150 kW peak power at a wavelength of 3 371 A. Correlations between temporal behaviours of discharge current, voltage and laser power density are shown.Des mesures simultanées et résolues temporellement des paramètres électriques et de la densité de puissance d'un laser à azote à excitation transversale sont présentées et analysées. Les mesures expérimentales sont réalisées sur un laser à courte cavité (380 mm de longueur active) fonctionnant à basse pression (40 torr) et délivrant jusqu'à 150 kW de puissance crête à la longueur d'onde 3 371 A. Certaines corrélations entre les évolutions temporelles du courant de décharge, de la tension et de la densité de puissance laser sont montrées